Half a World Away From Harvey, Global Warming Fueled Deluges Now Impact 42 Million People

Rising sea surface temperatures in South Asia led to more moisture in the atmosphere, providing this year’s monsoon with its ammunition for torrential rainfall. — The Pacific Standard

While flooding is common in the region, climate change has spurred dramatic weather patterns, greatly exacerbating the damage. As sea temperatures warm, moisture increases, a dynamic also at play in the record-setting rainfall in Texas. — Think Progress

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With Harvey delivering its own hammer blow of worst-ever-seen rainfall to Texas, 42 million people are now impacted by record flooding half a world away. The one thing that links these two disparate disasters? Climate Change.

A Worsening Flood Disaster in South Asia

As Harvey was setting its sights on the Texas Coast this time last week, another major rainfall disaster was already ongoing. Thousands of miles away, South Asia was experiencing historic flooding that seven days ago had impacted 24 million people.

At the time, two tropical weather systems were developing over a very warm Pacific. They were angling in toward a considerably pumped up monsoonal moisture flow. And they appeared bound and determined to unleash yet more misery on an already suffering region.

As of Monday, the remnants of tropical cyclone Hato had entered the monsoonal flow and was unleashing its heavy rains upon Nepal. The most recent in a long chain of systems that just keeps looping more storms in over the region to disgorge they water loads on submerged lands.

By Wednesday, the number of people suffering from flooding in India, Bangladesh and Nepal had jumped by 18 million in just one week to more than 42 million. With 32 million impacted in India, 8.6 million in Bangladesh, and 1.7 million in Nepal. More tragically, 1,200 people have perished due to both landslides and floods as thousands of square miles have been submerged and whole regions have been crippled with roads, bridges, and airports washing out. Adding to this harsh toll are an estimated 3.5 million homes that have been damaged or destroyed in Bangladesh alone.

Worst impacts are likely to focus on Bangladesh which is down-stream of flooded regions in Nepal and India. As of last week, 1/3 of this low-lying country had been submerged by rising water. With intense rains persisting during recent days, this coverage is likely to have expanded.

Hundreds of thousands of people have now funneled into the country’s growing disaster shelters. A massive international aid effort is underway as food and water supplies are cut off and fears of disease are growing. The international Red Cross and Red Crescent and other relief agencies have deployed over 2,000 medical teams to the region. Meanwhile, calls for increased assistance are growing.

Warmer Oceans Fuel Tropical Climate Extremes

As with Harvey, this year’s South Asia floods have been fueled by much warmer than normal ocean surface temperatures. These warmer than normal ocean surfaces are evaporating copious amounts of moisture into the tropical atmosphere. This moisture, in turn, is intensifying the monsoonal rains.

(Very warm ocean surface temperatures related to global warming are contributing to catastrophic South Asian flooding in which 42 million people are now impacted. Image source: Earth Nullschool.)

In the Bay of Bengal, ocean surfaces have recently hit about 3 C above the three decade average. But ocean waters have been warming now for more than a Century following the initiation of widespread fossil fuel burning. So even the present baseline is above 20th Century temperature norms. At this point, such high levels of ocean heat are clearly having an impact on tropical weather.

In an interview with CNN, Reaz Ahmed, the director-general of Bangladesh’s Department of Disaster Management noted last week that:

“This is not normal. Floods this year were bigger and more intense than the previous years.”

Further exacerbating the situation is that fact that glaciers are melting and temperatures are rising in the Himalayas. This increases water flow into rivers during monsoon season even as glacial melt flow into rivers is reduced during the dry season. It’s kind of a flood-drought whammy in which the dry season is growing hotter and drier for places like India, but the wet season is conversely getting pushed toward worsening flood extremes.

Links:

The Pacific Standard

Think Progress

Earth Nullschool

Nepal, India, Bangladesh Floods Impact Millions

NASA Worldview

Hat tip to Colorado Bob

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So Let’s Talk About the Science of How Climate Change Kicked Harvey into Higher Gear

Harvey is finally on the move.

After making a second landfall early Wednesday, the storm is passing slowly out of the East Texas region that has suffered so much first from Harvey’s initial lashing as a rapidly intensifying category 4 storm, and second from its long-lasting and unprecedented rainfall.

(Harvey rapidly intensifies into a category 4 monster just prior to landfall. This rapid intensification and other climate change related factors helped to make Harvey a more dangerous storm. Image source: NASA.)

At this point we can take a bit of a step back to look at the larger situation. Sure, impacts will probably continue and even worsen for some areas. And due to a historic pulse of water heading downstream, the hammered city of Houston is far from out of the woods.

But as with Sandy and so many other freakish strong storms in a present climate that has warmed by around 1.2 C above pre-industrial values, we would be remiss if we didn’t discuss the climate change related factors that gave Harvey more fuel, that helped it to rapidly intensify, that worsened its flooding — both from rains and from storm surge, and that may have helped to produce a still pocket in the upper level winds that allowed it to stick around for so long.

Warmer Ocean Surfaces Mean More Rapidly Intensifying Storms, Higher Peak Intensity of Worst Storms

Hurricanes like Harvey cannot readily form in cool waters below a range between 70 and 75 degrees Fahrenheit. Ideally, the storms require ocean surface temperatures warmer than 80 degrees (F). And the more heat that’s available at the ocean surface, the more energy that’s available for a storm when it does form.

This energy comes in the form of atmospheric lift. In other words, air rises off the water more vigorously as water temperature rises. This lifting energy is called convection. And the more that’s available, the more powerful storms can ultimately become.

(Sea surface temperatures were between 1 and 2 degrees Celsius above average as Harvey approached Texas. Human-forced climate change is causing the oceans to warm. This, in turn, provides more fuel for hurricanes like Harvey — helping them to rapidly intensify and pushing their peak strength higher. Image source: NOAA.)

According to Dr Michael Mann, Ocean surfaces in the Gulf of Mexico are fully 1 to 1.5 degrees Celsius warmer, on average, than they were just 30 years ago. This warming provides more energy for storms that do form. And this, in turn, raises the top potential intensity of storms.

Some scientists, like Dr. James Hansen, refer to this prevalence of worsening extremity as loading the climate dice. If, in the past, we were rolling with a die six with a 1 representing the lowest storm intensity and a 6 representing the highest, we’re now rolling with something like a die six +1. The result is that the strongest storms are stronger and the absolutely strongest storms have an ability to achieve previously unattainable strengths due to the fact that there’s a lot more energy there to kick them into a higher state.

Increased potential peak storm intensity as a climate change factor does not necessarily result in more tropical storms forming overall. That part of the science on hurricanes is highly uncertain. But that heat engine in the form of warmer surface waters is available for the storms that do form to tap. And that can make them a lot stronger and more damaging than they otherwise would have been.

(Loading the climate dice — changes in frequency of cold and warm temperatures also has an impact on heatwaves, droughts, wildfires, storm intensity, and heavy precipitation events. Image source: NASA.)

As Harvey approached land, it tapped the energy of this much warmer than normal ocean surface. And that energy caused the storm to rapidly strengthen — first from a minimal tropical storm to a Hurricane, and then from a minimal hurricane to a Category 4 monster. Meteorologists tend to call such periods of rapid intensification — bombification. This term comes from minimum pressures that rapidly drop in swiftly strengthening storms — seeming to bomb out. And due to warming, the science indicates that rapid strengthening is also more likely. With some models pointing toward a 10-20 fold increase in the frequency of rapidly intensifying storms by the end of this Century if human forced warming of ocean surfaces continues.

Warmer Atmosphere Means Heavier Rainfall

Related to a warming of the ocean surface (and land surfaces as well) is the basic scientific fact that such warming causes the amount of water vapor in the atmosphere to increase. In total, with each 1 degree Celsius of warming near the Earth’s surface, the atmosphere ends up holding about 6-7 percent more moisture. The properties of this warming-driven increase in atmospheric moisture are described by the scientifically proven Clausius–Clapeyron relation which defines, in meteorology, how atmospheric water vapor content is driven by various factors, including temperature.

If we dig just a little bit further into our understanding of how this scientific driver impacts the atmosphere in a warmer world, we find that not only does the moisture content of a warmer atmosphere increase, but both the rates of evaporation and precipitation increase.

 

(Global warming has brought with it a sharp increase in the number of record-breaking daily rainfall events. This is due to the fact that a warmer world holds more storm-fueling moisture in its atmosphere. This warmer, wetter atmosphere increased the peak potential rainfall from Harvey enabling it to smash records for rainfall rates and precipitation totals. Image source: Increased Record-Breaking Precipitation Events Under Global Warming.)

It is here that we return to the loaded climate dice mentioned above. If, as we find today, the Earth is about 1.2 degrees Celsius warmer than in the past, then the atmosphere holds more moisture. About 7-8 percent more. And since there’s more heat, evaporation is more intense where it does happen. This loads the climate dice for more intense droughts. But since what goes up in the form of evaporation results in a heavier load of moisture in the higher clouds and in the storms that do form, the rains that follow will also tend to be more intense. This loads the dice for more severe rainfall events. And we have a very clear scientific observation that the most extreme rainstorms are becoming much more intense overall (see above graphic).

For Harvey, this meant that more moisture was available to provide the record-setting rainfall amounts coming from that system. Peak rainfall totals from the storm are now at nearly 52 inches. This is the most rainfall ever to occur in Texas from a tropical system in our records. A measure that may also break the all-time U.S. record for rainfall from a tropical storm. And Harvey was enabled to produce such high rainfall amounts by a warmer atmosphere.

Harvey a Brown Ocean Cyclone?

Increasing rates of evaporation and precipitation had one obvious effect in Harvey — they increased the potential severity of rains coming from this kind of storm. But they also increase the ability of storms like Harvey to maintain strength or even intensify over land. If, for example, a storm like Harvey dumps a very heavy load of rainfall over land and if the evaporation from these recent rains has increased in a warming world, then storms like Harvey can tend to draw strength back from what amounts to a small ocean on land.

A recent NASA scientific paper on this issue describes a Brown Ocean effect. The 2013 NASA paper noted:

Before making landfall, tropical storms gather power from the warm waters of the ocean. Storms in the newly defined category derive their energy instead from the evaporation of abundant soil moisture – a phenomenon that Andersen and Shepherd call the “brown ocean.”

…The research also points to possible implications for storms’ response to climate change. “As dry areas get drier and wet areas get wetter, are you priming the soil to get more frequent inland tropical cyclone intensification?” asked Shepherd.

In essence, cyclones are better able to maintain strength or even re-intensify over wet areas of land in a warmer world due to increasing levels of evaporation and it was Harvey’s ability to maintain tropical storm strength over land for up to three days that helped to enable it to keep dropping such heavy volumes of rain.

Higher Seas Mean Worse Storm Surge Flooding

A warmer climate also brings with it the melt of continental glaciers and the thermal expansion of ocean waters. As glaciers flood into the world’s oceans, they rise. And since fossil fuel burning began at the start of the industrial age this related warming of the Earth and melting of glaciers has caused the oceans around the world to rise by more than 20 centimeters globally.

(Global warming increases the base ocean level which, in turn, worsens storm surge flooding. Harvey’s storm surge came in on this higher ramp. Image source: Sea Level Rise Science.)

Such higher seas alone are causing some coastal settlements to flood even on sunny days. But when storms like Harvey come roaring ashore, they do so on a higher overall launching pad. And this produces a multiplier effect for storm surge damages. A multiplier that would not have been there if the world hadn’t warmed.

Polar Warming Contributes to Blocking Patterns That Make Weather Stick Around in One Place Longer

Another climate change related factor that contributed to Harvey’s danger was its persist hovering over the same region. Harvey would not have been as damaging for Texas and the Gulf if it hadn’t hung over East Texas for more than five days. But here, again, we find that climate change related factors appear to be contributing to the increased lingering of various extreme weather producing systems.

To understand how, we need to look at the upper level atmospheric circulation pattern that moves weather systems from place-to-place. In other words — the Jet Stream. Climate change influences the Jet Stream by generating more warming at the poles than near the Equator. This in turn, according to the research of scientists like Dr Jennifer Francis, changes atmospheric slope. Warmer poles, in other words, create a taller atmosphere at the poles relative to the Equator.

(A high amplitude ridge-trough pattern helped to create a stagnant upper air slot in which Harvey stalled. This voiding of upper level steering currents enabled Harvey’s persistence. Some scientists are pointing toward increasing prevalence of these kinds of high amplitude ridges and troughs related to polar warming warming which is an upshot of global warming. Image source: Earth Nullschool.)

Since atmospheric slope and temperature differences between the poles and Equator drive the speed of the Jet Stream, warmer poles cause the Jet Stream to slow down and meander. This generates big ridges and deep troughs. It also appears to assist the generation of large blocking high pressure systems. And all of these features can tend to cause weather patterns to get stuck.

This year, a persistent trough in the Eastern U.S. has generated a consistent stormy pattern and aided in the firing of powerful thunderstorms that produced record rains over places like Kansas City, Missouri. In the West, a persistent ridge has produced record heat and very extreme wildfires while aiding the formation of a very intense flash drought in Montana and the Dakotas. Harvey got stuck in a stagnant pocket between these two relatively fixed weather patterns. A climate change related feature that may have increased the duration of Harvey and facilitated its record rains falling over such a long period.

Other Factors — Interaction With The Eastern Trough

Finally, we can state that Harvey’s interaction with the very deep eastern trough also helped to fuel it. The trough provided a moisture and instability kick to Harvey as it moved over Texas — helping to wring out tropical moisture over the Lone Star State. And if we accept the fact that polar warming contributed to the depth of this eastern trough by slowing down the Jet Stream, then its interaction with Harvey was also a climate change related factor.

Qualifying This Discussion

What can be said with certainty is that climate change did not cause the hurricane. That hurricanes do happen in a normal climate. But this is the same same thing as saying that home runs happen in both middle school and major league baseball. It’s all baseball, but the factors from one to the other have qualitatively changed in an obvious fashion. The same thing happens to weather in a warming world. And it is due to the changes in these underlying factors that we can say without a doubt that climate change made Harvey worse.

What we can also say is that our certainty of all these various climate change related factors involved varies. For example, we can say with very high certainty that global warming is worsening rainfall extremes and that sea level rise is worsening storm surges. We can say with a good level of confidence that the peak intensity of the worst storms is also increasing and that bombification is more likely. And we can say with moderate confidence that climate change is altering atmospheric circulation patterns (an issue that is still under considerable debate).

But the varying degrees of certainty with regards to these aspects do not change basic facts. Your climate is your weather averaged over 30 years. And if the world warms, both your climate and your weather change.

Harvey Intensifies Slightly Just Prior to Second Landfall

Tropical Storm Harvey, which has dumped more than 51 inches of rain over parts of Texas and flooded hundreds of thousands of homes, intensified this afternoon over the Gulf of Mexico as it continued to move to the North-Northeast.

(Visible satellite imagery of Tropical Storm Harvey late afternoon on August 29th shows the storm slightly re-intensifying before a second landfall with strong rain bands again threatening Houston. Image source: The National Hurricane Center.)

As of the 4 PM CDT advisory from the National Hurricane Center, Harvey’s minimum central pressure had dropped to 994 mb even as its maximum sustained winds increased to 50 mph. This made Harvey a still rather weak tropical storm is it continued to lash sections of Eastern Texas and Louisiana with winds and rains.

Now a 5-day long event since threatening the Texas Coast as a category 4 storm on Thursday, Harvey has produced the worst flooding in Texas state history. In Houston, dams designed to contain a 1,000 year flood are overflowing — increasing already catastrophic flooding throughout the beleaguered city.

(After a brief respite, Houston’s eastern suburbs are again seeing heavy rain from Harvey. Image source: National Weather Service.)

Very heavy rains have fallen over Houston since Saturday. But during the early afternoon hours rains had lightened over the city as the heaviest squalls shifted further east over Beaumont. Recent weather radar imagery from the National Weather Service, however, has shown more intense rain bands again back-filling over Eastern Houston in coordination with Harvey’s recent re-intensification.

Tonight, Harvey is expected to track inland before being pulled northward by a trough and finally leaving Southeastern Texas behind. But not before giving the region one last lashing over the next 12-24 hours or so while dumping another 6-12 inches of rain.

RELATED STATEMENTS AND INFORMATION:

Links:

The National Hurricane Center

National Weather Service

Worst Tropical Rainfall Event in Texas History

Worst Tropical Rainfall Event in Texas History Made More Deadly by Climate Change: Harvey Totals Now Top 49 Inches

We can’t say that Hurricane Harvey was caused by climate change. But it was certainly worsened by it. — Dr. Michael Mann

Harvey is already the worst rainstorm in U.S. history and it’s still raining.Meteorologist Eric Holthaus

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It’s the fifth day of an unprecedented rain event that one of the world’s top scientists is saying was made worse by climate change. Flood totals as of earlier this morning topped a record-smashing 49 inches. Emergency management officials are saying that this is a 1,000 year flood event (and it could get worse). And the rains are still falling as levees in and around the city of Houston over-top or fail.

If peak rainfall was the whole of this story, then things wouldn’t be quite so bad for Houston and other Texas cities. But with this particularly severe storm it’s a combination of size, severity and duration that has produced such terrible floods. Harvey’s persistent stall has brought very severe rains to a large swath running all the way from southeast Texas in an arc through Mississippi. And a huge flood basin from Victoria to Austin to Lufkin to Lake Charles has now received between 8 and nearly 50 inches of rain as of early Tuesday.

Such a large swath has resulted in a more significant pulse of waters flooding into streams, lakes, and reservoirs. This depth of zonal flooding generates more water pile ups as flows move downstream. Resulting in higher peaks at rivers in places like Houston and putting more stress on water management infrastructure. An infrastructure that was designed to handle the 100 to 1,000 year floods of a gentler climate but not the so-called 1,000 year or worse floods of an atmosphere loaded up with a much greater portion of storm-fueling heat and moisture.

That this will be the worst flood in Texas history by a number of measures goes without question. That the flood was made worse by climate change is a scientific fact. That Texas is still getting pummeled by a tragic blow that is costing both lives and tens of billions of dollars in damages is a foregone conclusion.

At this point, the question we need to be asking ourselves is how can we prepare for more of these kinds of extreme rainfall events — which are surely coming. And how can we honestly work together to reduce both their future intensity and damage? How can we ultimately protect lives and property in a world we have made more dangerous by burning fossil fuels and dumping carbon into the atmosphere? And how quickly can we resolve ourselves to stop making the problem worse?

UPDATED (1)

RELATED STATEMENTS AND INFORMATION:

Links:

Hurricane Harvey Made More Deadly by Climate Change

National Weather Service Houston

The Capital Weather Gang

Harvey is Already the Worst Rainstorm in U.S. History and it’s Still Raining

Houston Levee Failures

 

Houston Levee Failures: Reports Indicate that Reservoirs are Being Strained Past the Spillover Point

DEVELOPING STORY:

News reports Monday night from Houston KTRK indicated that water levels at Addicks and Barker Reservoirs were continuing to rise sharply despite controlled releases starting at 1 AM on Monday. According to these reports, the reservoirs had received upwards of 25 inches of rainfall. The National Weather Service indicated that another 25 inches may be on the way in total. And despite the controlled release, reservoir levels were continuing to rise at a rate of 4 inches per hour.

(Addicks and Barker Reservoirs spill into Buffalo Bayou, which then flows into downtown Houston. Earlier today controlled releases were begun in an attempt to slow water rise in the reservoirs. This release is failing to prevent rapid water rise within and around these reservoirs. Movement of flood waters into the reservoirs is pushing waters into subdivisions near the reservoirs even as risk of levee failure is rising. Image source: Harris County Flood Control District and Weather Underground.)

Such unprecedented rainfall totals caused city officials to warn that: “This event has the potential to exceed a 1,000 year flood plain threshold.” It’s worth noting that the Levees in Fort Bend County were designed only to manage a 100 year flood event and that the expected 59 foot crest of the Brazos River represented an 800 year flood event.

But by evening, very heavy thunderstorms were running in to Houston across Galveston Bay. These storms again pummeled the city with extraordinary rainfall amounts — pushing flood thresholds still higher.

As a result, concern about the communities surrounding these reservoirs is hitting a fever pitch. Flooding is now expected in all of the 41 city subdivisions surrounding Barker and also in all of the 52 subdivisions surrounding Addicks. In addition, three other neighborhoods could see flooding if water flanks the Addicks spillway.

More concerning, however, is this statement from KTRK:

In addition to these neighborhoods, officials have called for a mandatory evacuation of Inverness Forest on Cypress Creek and Northwood Pines on Spring Creek as a result of potential levee failures.

Throughout the day, there have been numerous indications that these reservoirs were under serious stress as more and more water rushed downstream. As of late afternoon, water levels had risen to 105 feet in the Addicks reservoir. And observers of various levees at the time had already noted that water was near overtopping in some places. This tweet from Jeff Linder shows water very close to the top of the Inverness Levee.

By evening, Addicks had topped 106 feet and Barker was at 101 feet with the water still rapidly rising. Meanwhile, a dam upstream in Brazos County burst at 9 PM — further adding to the torrent heading toward Houston. With imminent danger of worse floods approaching, the National Weather Service subsequently issued a very clear warning that residents in the impacted neighborhoods should evacuate before 11 PM (CDT) or risk being stranded. Such a clear warning was an indication that disaster officials expected a high risk that at least some of the impacted levees would be breached or spill over.

Uncontrolled Releases and Failures Begin Tuesday Morning

By Tuesday morning, reports were coming in that the Addicks reservoir had topped 108 feet and that parts of the dam section of that reservoir near Buffalo Bayou was flowing out through the emergency spillway. This spillover is adding more water to Buffalo Bayou — a main river running through Houston and a significant source of flooding thus far. The Addicks Dam, as of 11 AM CDT remained structurally sound and the main issue with the levee at that time was due to uncontrolled spill out through the emergency spillway. As of early Tuesday, officials expected levels at Addicks Dam to peak at more than 110 feet this week. Risk of dam breakage at this time, according to officials, is said to remain low.

Officials, as of late Tuesday morning, were increasingly concerned about a Barker Dam overflow due to rising waters in the Barker reservoir as well. Water gauges at Barker had been put out of commission by the rising waters as of last night. So it is difficult to clarify the situation at the Barker Dam at this time. However, Barker is expected to exceed the 101 foot level in which uncontrolled overflow occurs, ultimately peaking at 104 feet. As with Addick, Barker Dam presently remains structurally sound with no major risk of imminent breakage, according to officials.

Meanwhile, a levee failure has been reported Tuesday morning in Brazoria County, south of Houston, at Columbia Lakes. Emergency officials in the area were very concerned about residents sheltering in their homes in this region — urging all Columbia Lakes residents to “get out!”

(UPDATED — UPDATES TO FOLLOW)

RELATED REPORTS AND INFORMATION:

Links:

Addicks Dam Begins Overflowing

KTRK

KBXT

Harris County Flood Control District

Weather Underground

Hat tip to wili

Hat tip to eleggua

Hat tip to Andy in San Diego

With up to 42 Inches of Rain Already Dumped on Texas, Harvey’s Track Over Gulf Means 10-21 More to Come

By mid-afternoon Monday, a still very wet Harvey had back-tracked over the Gulf of Mexico. The storm has now dumped unprecedented, record-setting rains totaling more than 30 inches over a Houston that is being forced to release dam water into already flooded regions in order to prevent over-topping or worse. Meanwhile, nearby Dayton, as of this morning, had received nearly 40 inches since the storm began on Friday. And as of noon, Baytown, TX has seen 41.77 inches over the sixty hour storm period.

Harvey’s circulation is now located along the coast south and west of Galveston and it is edging slowly back over the Gulf of Mexico. The storm is still drawing copious volumes of moisture up from the Gulf. This moisture flood is still fueling a massive shield of rain and thunderstorms stretching over much of Eastern Texas, a good portion of Louisiana and parts of Mississippi. And with its center now moving back over water, this moisture flow and its related thunderstorms are again starting to intensify.

 

(Harvey’s rains shield reinvigorates as the storm once again crosses into the Gulf. Image source: The National Weather Service.)

Presently, the most intense rains from the system are clustered over Houston (still), adjacent portions of the Texas Coast, and Eastern Louisiana.

As of 4 PM CDT, Harvey had re-intensified somewhat to 997 mb with maximum sustained winds near 45 miles per hour. Over the next 24 hours, Harvey is expected to back slowly southward over the Gulf of Mexico, then turn back northward. By late Tuesday, the tropical storm is again expected to be closing in on the Texas Coast for a likely second landfall late Tuesday or early Wednesday.

Present satellite imagery shows Harvey reintensifying somewhat in the infrared — with stronger storms firing near Harvey’s Center and just to the north in the Houston region. A dry slot of air in the storm, however, is likely to limit re-strengthening as the storm passes over water during the next 12-24 hours.

(Harvey appears to restrengthen somewhat in the infrared satellite as it taps Gulf heat and moisture. Image source: The National Hurricane Center.)

As such, Harvey at present is still a rather dangerous rain event. An event that is now re-gathering some of its strength and intensity as it digs more deeply into Gulf moisture.

Earlier today, meteorologists noted an optimistic wedge of dry air moving into the system from Central Texas. Such a wedge would tend to tamp down rainfall rates over Houston and East Texas. And the region did get a bit of a respite from heavy rains earlier in the day. However, with the moisture tap to that abnormally warm Gulf now re-established, heavier rains are again filling in near the storm center and just to the north.

(NOAA is still showing a potential for in excess of 20 inches of rain in the Houston region even following the massive, historic deluge that has already been unleashed by a hurricane fueled by a record warm world. Image source: NOAA.)

As a result, Houston is likely to get socked with a third bout of very heavy rain tonight through tomorrow with a fourth bout likely on tap for late Tuesday night. And, presently, NOAA now predicts that up to another 21 inches of rain is on the way for the Houston region on top of the already historic totals of 20-40 inches that have inundated the city.

(UPDATED 7)

UPDATE (8): The latest advisory from the National Hurricane Center notes that:

Harvey is expected to produce additional rainfall accumulations of 10 to 20 inches through Thursday over parts of the upper Texas coast into southwestern Louisiana. Isolated storm totals may reach 50 inches over the upper Texas coast, including the Houston/Galveston metropolitan area. These rains are currently producing catastrophic and life-threatening flooding over large portions of southeastern Texas. DO NOT ATTEMPT TO TRAVEL IN THE AFFECTED AREA IF YOU ARE IN A SAFE PLACE. DO NOT DRIVE INTO FLOODED ROADWAYS. Please see warnings and products issued by your local National Weather Service office for additional information on this life-threatening situation.

This storm isn’t over folks. Not by a long shot.

RELATED INFORMATION AND STATEMENTS:

Links:

The National Weather Service

The National Hurricane Center

NOAA

Harvey Moves Back Over Water. Historic Rainfall Will Continue.

Hat tip to wili

Hat tip to eleggua

Nearing a Trillion Watts: By End 2017, Global Wind + Solar Capacity Will be 2.4 Times That of Nuclear

In 2017, the world will add about 80 gigawatts of new solar capacity. It will also add another 60 gigawatts of new wind capacity. This combined 140 gigawatts will push wind and solar to 940 gigawatts of global capacity — or nearly one trillion watts. A pace that’s ahead of even recent optimistic projections by about 25 gigawatts:

(Historic and projected global wind and solar capacity. Image source: Forecast International.)

Such a total renewable energy generation capability compares to a global 391.5 gigawatts of nuclear energy now in use around the world. In other words, solar energy by end 2017 will come close to surpassing total global nuclear energy capacity. And wind and solar combined will account for 2.4 times the amount of installed nuclear around the world.

The reason wind and solar are now rapidly eclipsing global nuclear capacity is due to simple economic competitiveness alone. By 2022, wind + solar is now expected to exceed 1,600 gigawatts. Or more than 4 times present nuclear capacity. Such a strong build rate comes on the back of rapidly falling costs for renewable energy systems. With wind and solar’s levelized costs of production now below that of all other new power sources in many places and with prices bound to continue falling through 2030, base economic incentives for adding renewable energy are now quite high. Add in the fact that these systems produce no harmful particulate or greenhouse gas pollution in use, and the appeal of such clean energy systems is difficult to contest.

(In the U.S. unsubsidized levelized costs of energy vastly favor wind and utility scale solar. And indication that other utility sources such as coal and gas are over subsidized by society. Image source: Clean Technica.)

Increasingly, coal and even gas fired power generation relies on subsidies and an uneven playing field to compete with renewable energy systems. With research from John Abraham indicating that from 2013 to 2015, global fossil fuel subsidies rose from a staggering 4.9 trillion dollars to an astounding 5.3 trillion dollars. And backwards-looking political bodies like the Trump Administration are increasing this highly distorting and harmful subsidy allotment still further.

There’s really no excuse for such an unequal and continuously tilting playing field considering the fact that fossil fuels are the main driver of a climate change that is contributing to catastrophic storms like Harvey and a rising ocean that is now threatening hundreds of cities around the globe. Considering the fact that about 7 million people die each year from air pollution primarily related to fossil fuel burning each year alone. With inexpensive and much cleaner alternatives now available, and with these alternatives proving increasingly competitive with the rickety and harmful old energy sources that the world’s tax payers unjustly prop up, there’s really no excuse in creating further delays for the far less dangerous and harmful clean energy systems we all deserve.

Links:

Forecast International

Clean Technica

Global Solar Capacity Set to Surpass Nuclear

Wind Energy Cost Reductions of 50 Percent Possible by 2030

Global Wind Energy Insight

Global Cumulative Installed Wind Capacity

7 Million Premature Deaths Annually Linked to Air Pollution

Trump Moves to Increase Subsidy for Coal on Federal Lands

 

Harvey’s Flooding Already Catastrophic and Another 2-3 Feet of Rainfall is on the Way

For Houston, a city that hosts a massive oil industry, it’s the climate change related flood version of the Fort McMurray fire. And we may well be witnessing, at this time, a tragedy that we could have at least in part prevented, but didn’t.

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Last week at this time, meteorologists were tracking a tropical cyclone moving across the Caribbean. 5-7 day models indicated that the system would enter the Gulf of Mexico by late week. This Gulf was hotter than normal. And for the past three months it had been dumping an over-abundance of moisture into an unusually deep summer trough over the Eastern U.S. This interaction between two features related to human-forced climate change was already producing very severe thunderstorms that generated record rainfall over places like Kansas City, Missouri.

Harvey was very moisture rich. It issued from a tropical convergence zone and monsoon cycle that had hit unusually high intensity — due, at least in part, to abnormally warm ocean surface waters injecting much higher than normal moisture loads into the tropical atmosphere. And early last week there was some serious concern that intense tropical moisture in the form of Harvey could combine with a Gulf and Eastern U.S. weather and climate pattern that had already produced unprecedented rains to generate ultimately catastrophic results.

These fears have now been realized.

As of this afternoon,  parts of Houston and Southeast Texas had received more than 30 inches of rainfall — with up to 26 inches falling in just one 24-hour-period. Hourly rainfall rates at times have hit an equally unprecedented rate of up to six inches per hour. For context, one inch per hour rainfall rates in the past have been considered extreme. Six inches per hour is just off the charts. In many places, the most rain ever to fall over a one day time-frame was breached.

As we have seen so often around the world from globally increasing instances of record rainfall, roads flooded, cars were abandoned, and people were forced to climb onto their rooftops to flee the rising waters. In a Houston that is increasingly looking like post-Katrina New Orleans, more than 1,000 emergency calls for water rescues had been received by this morning. And with rivers hitting never-before-seen heights in a flood-prone city that is also facing the effect of rising sea levels, the rains were showing little sign of abating.

(Pivotal weather shows up to 32 inches of additional rainfall for the Houston region through Tuesday. The storm, however, may last through Thursday or later. Image source: Pivotal Weather.)

As much as 1-3 feet of additional rain is still expected from the storm. In the worst case, this would bring ultimate rainfall totals to 50-60+ inches. In a litany that we are hearing practically everywhere now — this would be the worst rainfall event Texas has ever seen in our records. It might, ultimately, be the worst flood from rainfall the U.S. has ever seen.

Moreover, weather models now indicate that Harvey may slowly track back toward the Gulf of Mexico. If this happens, a storm that is already pulling severe volumes of moisture in from the Gulf could be somewhat re-invigorated. Such a result would bring a second pulse of intense rains to parts of Southeast Texas and possibly Louisiana.

(September 1 GFS model shows remnants of Harvey interacting with a tropical cyclone south of Baja to continue to pull rains over Texas and Louisiana. Image source: Earth Nullschool.)

An additional concern is the fact that later this week Harvey shows a possible interaction with another stationary tropical cyclone forming near the southern tip of Baja in the Pacific. The two storms appear to interact to draw still more moisture from the abnormally warm Gulf over Southeast Texas later this week. Of course, this GFS-based forecast is still longer range — and therefore less certain. But the models do seem to continue to indicate a persistent heavy rainfall potential for an already catastrophically flooded region over an unprecedented long time frame.

This is exactly the kind of extreme rainfall event that some of us have feared coming from a warmer, more moisture-rich atmosphere in which weather systems have tended, more and more often, to persist and produce long-lasting effects. For the sake of all involved, we are now reduced to prayers and hopes that the worst case does not continue to be realized.

(UPDATED 9)

RELATED REPORTS AND STATEMENTS:

Links:

The National Weather Service

The National Hurricane Center

Harvey has Unloaded 9 Trillion Gallons of Water

Catastrophic Flooding Beyond Anything Experienced in Houston

Global Number of Record-Breaking Daily Rainfall Events

Harvey’s Approach Brings Potential Severe 5-Day Rainfall Event for Texas and Louisiana

Pivotal Weather

Earth Nullschool

Hat tip to Greg

Hat tip to eleggua

Not time to Let Our Guard Down With Harvey; Rainstorm Expected to Last 5-9 More Days

As of early afternoon on Saturday Harvey was about to be downgraded to a strong tropical storm after slamming into the Texas coast as a Category 4 monster hurricane packing 130 mph sustained winds. Residents along the coast are just now starting to assess the initial damage from this first major blow. However, the big rain event that is Harvey is just now getting started.

(Harvey’s rains expand over Eastern Texas at 245 PM EST. Image source: National Weather Service.)

According to the National Hurricane Center, the storm’s forward speed has now slowed down to about 2 miles per hour in a north-bound direction. Meanwhile, its shield of encircling rains is expanding to cover most of eastern Texas. These rains are very intense — producing accumulations of more than 1 inch per hour in many locations. And with Harvey stalling out, such heavy rains are expected to persist over basically the same region and at a similar high intensity for at least the next four days. After that time, Harvey is expected to persist and rains of lighter, but still flood-producing force, may continue to fall over parts of Texas for up to five more days.

(Harvey has already dumped nearly 15 inches of rain on some locations. Despite this fact, NOAA is still predicting more than 20 inches of additional rain. Some models are indicating that final totals could range from 40-60 inches in some locations after a 6-10 day rain event. Image source: NOAA.)

It’s worth noting that though up to 15 inches of rain have already fallen from Harvey, the longer range models still show in excess of another 20 inches coming from the storm over the next week. Many models indicate that more than 40 inches of rain could fall in total. And some of our best models yesterday indicated a potential for up to 60 inches in some locations by the time all is said and done.

In other words, this storm is far from over. The main event, in which Harvey may ultimately produce historic rainfall totals, is just getting ramped up. So now is not the time to relax our guard.

(UPDATED 1)

Links:

See Notes on Climate Change’s Influence on Harvey Here

The National Hurricane Center

National Weather Service

NOAA

Rainfall Rising Nearing 15 Inches in Some Locations

Global Forecast System Model Reanalysis

Harvey’s Mammoth Deluge Potential: Some Models Are Showing Storm Could Produce Five Feet of Rain

Media, Texas, and Gulf Coast residents take note: the thing to be most concerned about with regards to Harvey is not its admittedly life-threatening storm surge and strong winds, but what is shaping up to be a potentially historic rainfall event.

*****

The latest update from the National Hurricane Center shows that Harvey continues to strengthen and is now a category 4 storm. Packing 130 mph winds and a 941 mb minimum central pressure, the storm is certainly now very powerful. This new intensity is above the NHC’s previously expected peak strength for the storm just prior to landfall late tonight. The situation is thus becoming ever more dangerous.

But with Harvey, the serious concern we are facing is not just the usual and notably very dangerous high winds and storm surge flooding that go along with a category 4 storm. We are also looking at very severe and long lasting flooding rains that will have the potential to cause damage and disruption for not just months but for years to come.

A Devastating Rainfall Potential

(Southeast Texas has never seen 60 inches of rainfall from a tropical system. But that potential exists with Harvey.)

Consensus models now predict that peak rainfall totals will be around 35 inches in association with Harvey. This is due to the dual facts that Harvey is currently a very moisture-rich storm and that the storm is expected to stall for between 5 and 10 days following landfall. The storm is predicted to hover along the coastline, drawing in an unusually intense flow of moisture from a much warmer than normal Gulf, and to generate severe thunderstorms hour after hour, day after day. And this kind of rain event, if it emerges, could produce a disaster of historic proportions for Texas.

It’s worth noting that rainfall totals could also exceed the consensus forecast. Some models are now predicting upwards of 50 or 60 inches of rainfall by the time Harvey leaves the Texas area later next week (see top image above). The highest rainfall amounts ever produced by a tropical cyclone, in our records, for Texas is 48 inches. But there’s at least some possibility, with the perfect rainstorm that appears to be shaping up in Harvey, that these ultimate rainfall totals will be exceeded and a disaster of unprecedented proportions could emerge. But even if this worst-case doesn’t emerge, a 35 inch rainfall event would wreck untold destruction upon Texas’s southeastern cities.

Harvey strengthening as it moves toward shore

( Harvey rapidly strengthening to CAT 4 as it nears landfall. Image source: National Hurricane Center.)

Normally soft-spoken forecasters like Bob Henson and Eric Holthaus are not mincing words over the potential severity of the present situation. Last night, Bob Henson on twitter asked people: “Please don’t fixate on whether Harvey arrives as a Cat 2, 3, or 4. It’s the mammoth rainfall amounts (up to 35″) that will affect millions.” Meanwhile, Eric Holthaus warned: “This is scary. I have never seen a rainfall forecast like this in my entire career. Texas will be recovering from for years.”

Of course, we could dodge a bullet and rainfall totals could be lower for Harvey. It’s just that this event is currently trending toward a near worst case or worst case deluge-type storm that produces very heavy rains over the same region over nearly a week-long period.

Conditions in Context — This is Not Your Father’s Atmosphere

(The number of record rainfall events has increased dramatically during recent years. An observation attributed to human-forced climate change. Image source: Increased Record-Breaking Precipitation Events Under Global Warming.)

During recent years, a warmer than normal atmosphere has been producing more and more intense rain storms. The number of record daily rainfall instances around the world has been rising precipitously (see image above). This increasing severity is, in large part, due to the fact that human-forced warming amps up the hydrological cycle — producing more intense rain storms and more intense droughts. In other words, the climate dice are loaded for extreme rainfall and droughts in the present atmosphere. And it is in this atmosphere that Harvey has emerged. So we shouldn’t at all discount the fact that Harvey’s potential worst impacts from rainfall are now higher than they would have been even just a few decades ago. And this is one of the major reasons why we are seeing such a historic potential out of Harvey.

UPDATED (4)

UPDATE (5): As of 800 PM CDT the eye of Harvey crossed the coastline somewhere between Corpus Christi and Port O’Connor. Unfortunately, this storm is just getting started as a very severe one week long rain event is about to follow.

UPDATE (6): As of 1000 PM CDT and just following landfall, Harvey’s minimum central pressure had fallen to 938 mb. An indication that the storm was still strengthening as it began to cross the coastline. According to these reports (here and here), this is the 4th lowest barometric pressure recorded for a hurricane at landfall on the Texas coast since 1900. Maximum sustained winds remained at 130 mph with gusts to 160 mph.

Links:

National Hurricane Center

National Weather Service

Increased Record-Breaking Precipitation Events Under Global Warming

Greg Carbin

Eric Holthaus

Bob Henson

Hat tip to Greg

Hat tip to Titania

Hat tip to Wili

Hat tip to Andy in San Diego

Hat tip to Wharf Rat

Hurricane as Rain Bomb — Rapidly Intensifying Harvey Threatens to Dump 20-35+ Inches on Texas

A hurricane moving over the much warmer than normal waters of the Northern Gulf of Mexico is expected to rapidly strengthen to major status with 125 mph sustained winds over the next 12 hours before making landfall. Such rapid intensification brings with it the risk of severe storm surge flooding and damaging winds along the U.S. Gulf Coast. However, one of the most worrying features of this system is that it is incredibly moisture rich and new models now show a potential that the storm will dump as much as 20-35+ inches of rain across parts of Texas as the storm stalls over the region for 5-6 days.

(Present model guidance for Hurricane Harvey’s rainfall totals show a significant flooding potential for Texas. Note that maximum rainfall potential in this model is 40.6 inches.)

By late afternoon on Thursday, Harvey was a minor hurricane packing 85 mile per hour winds with a minimum central pressure of 976 mb and moving through the Central Gulf of Mexico on a path toward Texas. The storm was about 305 miles to the southeast of Corpus Christi, Texas and was moving toward the northwest at about 10 miles per hour. A curve toward the north is expected in the next 12-24 hours. Such a track would bring the storm adjacent to the Texas coast by some time late Friday or early Saturday.

As the storm moves north and west, it is expected to tap the warmer than normal waters of the Gulf of Mexico in the range of 87 to 88 degrees Fahrenheit and rapidly intensify into a major hurricane packing 125 mile per hour or higher winds.

(Rapidly intensifying Harvey approaches the Texas coast on Thursday. Image source: The National Hurricane Center.)

This is presently a very dangerous situation with the National Hurricane Center warning, as of the 4 PM CDT advisory that the storm is still expected to ‘rapidly intensify.’ And that peak intensity estimates could be conservative at this time. The storm will then bring 6-12 foot or higher surges to parts of the Texas Coast before moving slowly inland.

We should point out that some of the model guidance from earlier in the day predicted a very intense storm. This morning’s GFS run showed a 938 mb minimum central pressure just before the eye wall landfall late Friday. Such pressures are more consistent with a category four storm with maximum sustained winds in the range of 130 to 156 mph. This afternoon’s intensity guidance from GFS has backed off a little bit to 948 mb — which is more in the range of a strong Category 3 storm which jibes with the most recent NHS predicted intensity of 125 mph.

(Harvey may be stronger than even current NHC guidance indicates. GFS models from earlier this morning showed a 938 mb storm by late Friday. Intensity in the models has subsequently backed off to 948 mb — which is equivalent to the strong category 3 strong that the National Hurricane Center now predicts. Image source: Tropical Tidbits.)

As the eyewall reforms and the storm’s intensification rate varies, we’ll tend to end up with different peak intensity forecasts. In any case, we are looking at a major hurricane producing serious impacts for Texas and the U.S. Gulf Coast over multiple days.

Present model guidance further predicts that Harvey will slow down and then stall over southeastern Texas after making landfall — remaining basically stationary near the coast until Wednesday. As it hovers over this region, the storm will pull warm, moist air in over Eastern Texas while maintaining tropical storm intensity, generating a 5 to 6 day long severe flood event. In some scenarios, the storm may partially re-emerge over the Gulf and restrengthen. By Thursday, Harvey is expected to be picked up by a frontal system dipping in over the Central U.S. Exiting the state as it moves north and east.

(Harvey’s associated thunderstorms boil with hot intensity in this GOES satellite picture. Watch an animation of the massive storms swirling around Harvey here.)

Such a long-term stall is expected to bring significant torrential flooding rains over parts of Southeastern Texas. With averages of 17-32 inches over a wide swath and as much as 35+ inches in isolated locales. It’s worth noting that with Harvey’s top intensity continuing to trend toward major hurricane status, with a human-warmed atmosphere now capable of producing much more intense rainfall events, and with the storm expected to rain out over such a long period, some of the ultimate rainfall totals could be historic.

From the National Hurricane Center:

“The system is likely to slow down once it reaches the coast, increasing the threat of a prolonged period of heavy rain and flooding across portions of Texas, southwest Louisiana, and northeastern Mexico into early next week.”

(UPDATES TO FOLLOW)

Links:

The National Hurricane Center

Tropical Tidbits

Pivotal Weather

The Capital Weather Gang

Hat tip to Bostonblurp

China Builds 24 Billion Watts of Solar in Just Two Months as Trump Attacks Renewables and Defends Coal

Between the present U.S. Executive Branch and China, we can really tell which government is serious about being a moral leader on the critical issue of climate change and which government continues to wallow in the land of backwards thinking and heartless denial. For as the Trump Administration is doing everything it can to defend the coal-fired ‘Satanic mills’ that are so radically transforming the world for the worst while attacking renewable energy, China is continuing to build the solar farms that are capable of replacing them like gangbusters.

More than 10 Billion Watts Per Month

In June, China added a staggering 13.5 billion watts (gigawatts) of solar panels to its present large and growing solar fleet. In July, the country added another 10.5 gigawatts of solar. The two month total of 24 gigawatts is more than half the size of the total U.S. solar fleet of 44.4 gigawatts. In other words, China just added more solar capacity in two months than the U.S. added in all of the past two years.

(New solar market guidance for China shows an expected 180 to 230 GW of solar capacity by 2020. The present build rate indicates that even this range may be conservative. Image source: Renew Economy.)

As a result of this amazing build pace, China has already smashed through its 2020 solar goal of 105 gigawatts. The country now boasts a solar fleet of 112.3 billion watts. Long range forecasters now expect China to approach or exceed 200 gigawatts of solar by 2020 — or more than 20 percent the size of China’s present (and shrinking) coal fleet. And if China somehow maintained its amazing rate of solar installation during June and July, the country would exceed 200 gigawatts of national solar capacity by May of 2018.

No one presently expects that to happen. But China has surprised the world before. This is exactly the kind of surprise that a world wallowing in the ever-worsening impacts of climate change so desperately needs.  And the irony is that this new hope for rapid carbon emissions reductions is coming from China. Not the supposedly enlightened and progressive United States which is presently afflicted by the absolute worst form of backward-looking executive leadership imaginable.

Moral Leadership on Climate Change or Loss Thereof

I’m betting the people of the U.S. don’t want to be led down the path toward a new dark age of every worsening climate change and a fossil fuel resource curse write large by Trump. That we would much rather do our part to save the world from ramping climate destruction while taking leadership roles in the very new industries that U.S. innovation helped to create.

(Whether you’re optimistic or pessimistic about Earth’s climate sensitivity, the pathway toward worst case climate change [otherwise known as business as usual] lies in a world that continues to burn coal. So Trump’s defense of coal and attacks on renewables are, in essence, a defense of the worst case when it comes to climate change related disasters. Image source: The Brookings Institute.)

So what do we do?

We let the world know that Trump’s brand of leadership is not acceptable to Americans. That the true government leaders in the U.S. are those like California and Vermont and New York. That we support the future industries like those being pioneered by Musk and so many others. That we do not fear the future so much as recognize and embrace its mighty and admittedly difficult challenges. That we rise to the occasion by fighting for carbon emissions reductions and we do not falter.

Links:

China Added 10.5 Gigawatts of Solar in July

Trump’s Attack on Renewable Energy

Scott Pruitt’s Big Coal Lie

Renew Economy

The Brookings Institute

The Heavens Continue to Unleash Their Fury on South Asia — 24 Million Now Impacted by Flooding as Hato Approaches

The far heavier rains of a warming world have fallen hard over South Asia for nearly two months. In India and Nepal more than 18 million have been affected. But the floodwaters in these higher lands have combined into great torrents flooding downstream into Bangladesh. A country that is now witnessing its worst flood in 100 years as one-third of its low-lying land mass is covered by water.

(According to news reports, one-third of Bangladesh’s land mass is now covered by flood waters. August 19 satellite shot of Central Bangladesh shows raging rivers and flooded lowlands. Image source: NASA Worldview.)

The damage for such a poor country sitting at the forefront of a growing climate-change-based destruction from the recent extreme rain event has been tremendous. At least 115 people have died. Nearly six million have been impacted. The government has run out of medicine, water purification tablets, and temporary shelters for the hundreds of thousands of people displaced. More than 400,000 hectares of crops have been destroyed. Fully half a million homes have been damaged or lost. And there is not enough food or water to go around.

Fears of water-borne illness such as cholera are running high and calls for international aid in the flood-stricken state have grown more and more urgent. But the worst is not yet over as floodwaters from Nepal and India continue to swell Bangladesh’s multiple waterways over banks and into communities through central and southern parts of the country. And more rain may be on the way as another powerful storm system gathers.

(This is what happens if you keep burning fossil fuels. According to recent scientific reports, the global number of record-breaking rainfall events has increased dramatically during recent years. This increase has coincided with global temperatures exceeding the 1 C warmer than 1880s temperature threshold. Higher global temperatures amp up the hydrological cycle by squeezing more moisture out of land and ocean surfaces. A warmer atmosphere that’s more heavily loaded with moisture adds move convective energy to thunderstorms which tends to spike rainfall potentials for the strongest storms to higher levels. Image source: Increased Record-Breaking Precipitation Events Under Global Warming.)

In the Indian States of Bahir and Assam more than 430 people have lost their lives as schools have been buried under 8 feet of water, crops have been destroyed, roads have been washed out and power has been disrupted. As with Bangladesh, concern over contaminated water supplies has brought with it fears of water-borne illness as a gargantuan disaster relief effort gets underway.

Nepal has likewise seen its share of the pain and heartbreak. There, more than 140 people have perished in the floods as 40,000 families have been severely impacted.

(Hato, lower left, sets its sights on an already foundering South Asia on August 22nd. Image source: NASA Worldview.)

In total, more than 800 lives have been lost so far throughout these three countries. But the worst may be yet to come as, later this week, the remnants of Typhoon Hato will begin to affect the already-devastated region. Hato’s new injection of moisture and thunderstorms will bring back the potential for severe flooding over Nepal, India, and Bangladesh. Refilling rivers before they have a chance to subside and potentially generating yet one more major flood pulse for the lowlands.

(UPDATED)

Links:

Floods Claim More than 800 Lives Across India and Nepal

24 Million People Impacted by Flooding in India, Bangladesh and Nepal

NASA Worldview

Increased Record-Breaking Precipitation Events Under Global Warming

South Miami’s Solar Mandate Sets Example for Other Coastal Cities Facing Existential Threat From Sea Level Rise

Back in July, South Miami decided to require that all new homes built within city limits place solar panels on their roofs. The decision was made in an attempt to help slake the warming related impacts of sea level rise on the city by working to reduce carbon emissions.

South Miami Mayor Philip Stoddard recently noted:

“We’re down in South Florida where climate change and sea level rise are existential threats, so we’re looking for every opportunity to promote renewable energy. It’s carbon reduction, plain and simple. We have a pledge for carbon neutrality. We support the Paris Climate Agreement.”

South Miami joins six California cities now also providing rooftop solar mandates. These include San Francisco, Culver City, Santa Monica, San Mateo, Lancaster, and Sebastapol.

(How quickly greenhouse gas emissions are reduced has a considerable impact on the level of harm caused by future sea level rise. South Miami gets it. But what about the rest of the U.S. East and Gulf Coasts?)

With threats from rising oceans to coastal cities worsening, Miami’s decision is one that resonates with the interests of thousands of communities around the world. Nuisance flooding and increased instances of tidal flooding are on the rise pretty much everywhere. Meanwhile, some cities and island nations are in the process of being wiped off the map entirely as the pace of sea level rise quickens globally.

Coastal cities now have a vested interest in reducing carbon emissions as swiftly as possible. And Miami, like a number of cities in California, recognize that smart policy moves by municipalities can help to speed an energy transition away from the fossil fuels that now account for the vast majority of global carbon emissions.

Links:

South Miami Just Made a Huge Solar Rooftop Decision

South Miami is Going Solar

The Present Threat to Coastal Cities From Antarctic and Greenland Melt

Alaska Towns at Risk From Rising Seas Sound Alarm as Trump Pulls Federal Help

Harvey’s Approach Brings Potential Severe 5-Day Rain Event For Texas and Louisiana

For the third time in less than one month, powerful thunderstorms have dropped torrential rains in excess of 6 inches over Kansas City, Missouri. In the most recent event, a frontal system dropping down over the U.S. midsection encountered a very heavy load of atmospheric moisture streaming in off a much warmer than normal Gulf of Mexico. The result for Kansas City was the production of a towering boomer that dropped 10 inches in just one night.

Such an intense downpour turned roads into rivers and forced numerous residents to take refuge on rooftops as the waters rose once again. By morning, more than 130 water rescues had been called in across the city.

(NOAA predicts heavy rainfall for Texas and Louisiana over the coming week. Image source: NOAA.)

But this particular extreme event may be a simple prelude for what’s to come as the remnants of Harvey sets its sights on the Texas and Louisiana Gulf Coasts. Harvey is expected to strengthen into a tropical storm or weak hurricane over a very warm and moist Gulf of Mexico within the next 48 hours. Models then predict that it will combine its substantial moisture load with that of the frontal system responsible for such severe flooding in Missouri last night.

Already NOAA is predicting some very significant rainfall amounts over the coming days for the Texas and Louisiana coastal regions (see image above). And Harvey represents a considerable rainfall potential given the fact that it is expected to stall over Texas and Louisiana for the better part of 5 days. With regards to NOAA rainfall predictions, it is worth noting that extreme local precipitation values have significantly exceeded NOAA predictions recently in the case of the most severe thunderstorms.

(2 PM EST assessment of Harvey’s path and potential for restrengthening. Image source: The National Hurricane Center.)

One possible spoiler for Harvey reforming is an upper level low swirling just southeast of Texas. This low could rip Harvey apart. But if this happens, that system would tend to also direct Harvey’s moisture toward Texas, Louisiana and Alabama. In which case, strong rainfall potentials are also likely. However, the National Hurricane Center expects this upper level low and associated squalls to move toward the north and west — generating rainy conditions for Texas and Louisiana ahead of Harvey and creating space for a more powerful and heavily moisture laden storm to form.

Lower than normal precipitation totals in the region of Coastal Texas during the past couple of months may help to alleviate flood potential if the rains from Harvey remain on the somewhat lighter side (2-4 inches) and if the system continues to be disorganized. A more organized system would tend to bring heavier precipitation totals. However, it is worth noting that during recent years, much warmer than normal sea surface temperatures have combined with a warmer atmosphere to spike heavy rainfall totals. A result of human-forced climate change due to ongoing rampant fossil fuel burning.

Links:

NOAA

The National Hurricane Center

Historic Flooding Leaves One Dead

Over 130 Calls Made to Kansas City Fire Department Amid Life Threatening Flooding Overnight

Hat tip to Wharf Rat

The Economist Sounds Death Knell for the Internal Combustion Engine as Pathway Toward Carbon Emission Reductions Opens Wide

Earlier this month, The Economist prophetically declared that the “death of the internal combustion engine” is at hand. That the end for this inefficient fossil fuel burning monstrosity was “in sight.” And that, ultimately, “days were numbered” for a design that has so efficiently and so harmfully injected billions of tons of pollution into the Earth’s atmosphere.

(Gigafactories like this one being built in Nevada and numerous others being built in Southeast Asia are helping to enable a combined electrical vehicle and grid based renewable power revolution. Note that the Tesla gigafactory is still far from complete even though it is currently producing 5 GWh of lithium batteries per year. Production by end 2018 is expected to hit 35 GWh per year and ultimate production could hit as high as 150 GWh per year.)

The Economist notes that performance gains for electrical vehicles are quickly outpacing those of internal combustion engine based vehicles. That “today’s electric cars, powered by lithium-ion batteries, can do much better.” It finds that electrical vehicles are simpler to manufacture, easier to maintain, and easier to improve than traditional vehicles. It points to the fact that transportation based emissions alone result in 53,000 premature deaths each year in the U.S. vs the 34,000 who die due to car related collisions. And it cites research showing that transferring existing vehicles to electrical vehicles would reduce vehicle based carbon emissions by 54 percent using present grid sourced electricity generation. But it also rightly notes that as the grid becomes more and more dominated by renewable based energy systems, vehicle-based emissions will fall further — eventually reaching zero on a grid fully supplied by sources like wind and solar. Finally, The Economist notes that when mated with automation and ride share, EVs have the potential to reduce the number of vehicles on the road upwards of 90 percent (in the most optimistic assessments).

EVs are disruptive in that they’re becoming increasingly easy for start-up companies to produce — even if they are more difficult for traditional auto manufacturers who have heavily invested in fossil fuel based vehicle production infrastructure and parts chains. The result is that numerous independent EV shops are cropping up and that countries and industries who were not traditionally auto manufacturers are capable of making serious new entries. Tesla was an industry leader in this regard. But many such businesses are emerging all over the world from the U.S. to China to Europe to India and beyond.

(Increasing predictions for rate of EV build through 2040. Image source: The Economist.)

Moreover, the predicted rate of EV adoption just keeps rising. The Economist points out that UBS expects that 14 percent of all new vehicles in 2025 will be electric. And while UBS is among the more optimistic prognosticators, even traditional oil companies like Exxon are being forced to acknowledge that EVs will take larger and larger portions of the auto market. In just one year, from 2016 to 2017, Bloomberg adjusted its expected rate of new EV sales in 2040 upward from 400 million to 520 million, OPEC from 50 million to 250 million, and Exxon from 80 million to 100 million (see graphic above).

Such large and expanding build rates will certainly enable more and more rapid rates of global carbon emissions reductions. Not just through direct carbon emissions removal by replacing ICE based vehicles with EVs. But also by enabling the mating of batteries with renewable energy systems around the world. Tesla, which is today producing 5 gigawatt hours of battery storage in 2017 from its Gigafactory in Nevada is now starting to do just that. In South Australia, Tesla is involved in mating wind energy with battery storage even as it pursues a similar project in New Zealand and following its completion of a solar and battery based storage system for Kauai Hawaii.

(The amount of batteries available for both EVs and grid based storage is set to rapidly expand. Note that Tesla recently announced that its Nevada Gigafactory could eventually produce 150 GWh per year of battery storage. Image source: The Economist.)

By 2018, rate of battery production at the Tesla plant will accelerate to 35 GWh per year with the plant ultimately able to achieve near 150 GWh per year (according to Musk). Similar very large battery production plants are being built in Europe and China, with a number likely also slated for India in the near future. And the batteries produced in these plants can be used either in EVs or as a massive and growing energy storage pool that’s already capable of directly replacing coal and gas plants now operating on electrical grids.

Such was the economic reality for the Liddel Coal Plant in New South Wales Australia when AGL Energy decided it was more economic to replace the plant with wind, solar and batteries than to continue to burn coal and gas as a baseload energy supply. And this decision was made under present economic realities. Now imagine what those economic realities will look like when the world is producing more than an order of magnitude more battery storage each year at much lower cost and as wind and solar costs continue to fall. In other words, the electrical vehicle revolution is enabling the renewable power revolution and vice versa. And both are bringing forward the time when global carbon emissions start to consistently drop off. To support the advancement of one is to support the advancement of both — to the larger overall benefit of more rapid global carbon emissions reductions and a quickening ability to address the very serious issue that is human-forced climate change.

Links:

The Death of the Internal Combustion Engine

After Electric Cars, What Will it Take For Batteries to Change the Face of Energy?

Tesla Could Triple Planned Battery Output of Gigafactory 1 to 150 GWh

China is About to Bury Elon Musk in Batteries

Tesla to Build World’s Largest Lithium Ion Battery Plant in South Australia

The Economist Announces Death of the ICE

Liddel Coal Plant in New South Wales Will be Replaced By Wind, Solar and Batteries

Tesla Powerpack Will Join Wind Turbine at New Zealand Salt Factory

The Present Threat to Coastal Cities From Antarctic and Greenland Melt

Seas around the world are rising now at a rate of about 3.3 millimeters per year. This rate of rise is faster than at any time in the last 2,800 years. It’s accelerating. And already the impacts are being felt in the world’s most vulnerable coastal regions.

(Rates of global sea level rise continue to quicken. This has resulted in worsening tidal flooding for coastal cities like Miami, Charleston, New Orleans and Virginia Beach. Image source: Ice Melt, Sea Level Rise, and Superstorms.)

Sea Level Rise and Worsening Extreme Rainfall are Already Causing Serious Problems

Last week, New Orleans saw pumps fail as a heavy thunderstorm inundated the city. This caused both serious concern and consternation among residents. Begging the question — if New Orleans pumps can’t handle the nascient variety of more powerful thunderstorms in the age of human-caused climate change, then what happens when a hurricane barrels in? The pumps, designed to handle 1.5 inch per hour rainfall amounts in the first hour and 1 inch per hour rainfall amounts thereafter were greatly over-matched when sections of the city received more than 2 inches of rainfall per hour over multiple hours.

Higher rates of precipitation from thunderstorms are becoming a more common event the world over as the hydrological cycle is amped up by the more than 1 degree Celsius of temperature increase that has already occurred since 1880. And when these heavy rainfall amounts hit coastal cities that are already facing rising seas, then pumps and drainage systems can be stressed well beyond their original design limits. The result, inevitably, is more flooding.

(Dr Eric Rignot, one of the world’s foremost glacial scientists, discusses the potential for multimeter sea level rise due to presently projected levels of warming in the range of 1.5 to 2 C by mid to late Century.)

New Orleans itself is already below sea level. And the land there is steadily subsiding into the Gulf of Mexico. Add sea level rise and worsening storms on top of that trend and the crisis New Orleans faces is greatly amplified.

All up and down the U.S. East and Gulf Coasts, climate change driven sea level rise and a weakening Gulf Stream are combining with other natural factors that can seriously amplify an ever-worsening trend toward more tidal flooding. It’s a situation that will continue to worsen as global rates of sea level rise keep ramping higher. And how fast seas rise will depend both on the amount of carbon that human beings ultimately dump into the Earth’s atmosphere and on how rapidly various glacial systems around the world respond to that insult (see discussion by Dr. Eric Rignot above).

Presently High and Rising Atmospheric Carbon Levels Imply Ultimately Catastrophic Sea Level Rise — How Soon? How Fast? Can We Mitigate Swiftly Enough to Prevent the Worst?

Presently, atmospheric carbon forcing is in the range of 490 parts per million CO2 equivalent. This heat forcing, using paleoclimate proxies from 5 to 30 million years ago, implies approximately 2 degrees Celsius of warming this Century and about 4 degrees Celsisus of warming long term. It also implies an ultimate sea level rise of between 60 and 180 feet over the long term. In other words, if atmospheric carbon levels are similar to those seen during the Miocene, then temperatures are also ultimately headed for those ranges. Soon to be followed by a similar range of sea level rise. In the nearer term, 1.5 to 2 C warming from the 2030s to late Century is enough to result in 20 to 30 feet of sea level rise.

Of course, various climate change mitigation actions could ultimately reduce that larger heat forcing and final related loss of glacial ice. But with carbon still accumulating in the atmosphere and with Trump and other politicians around the world seeking to slow or sabotage a transition away from fossil fuels, then it goes to follow that enacting such an aggressive mitigation will be very difficult to manage without an overwhelming resistance to such harmful policy stances.

(Antarctic ice loss through 2016. Video source: NASA.)

That said, warming and related sea level rise will tend to take some time to elapse. And the real question on many scientists’ minds is — how fast? Presently, we do see serious signs of glacial destabilization in both Greenland and West Antartica. These two very large piles of ice alone could contribute 34 feet of sea level rise if both were to melt entirely.

Meanwhile, East Antarctica has also recently shown some signs of movement toward glacial destabilization. Especially in the region of the Totten Glacier and the Cook Ice Shelf. But rates of progress toward glacial destabilization in these zones has, thus far, been slower than that seen in Greenland and West Antarctica. Present mass loss hot spots are in the area of the Thwaites Glacier of West Antarctica and around the western and southern margins of Greenland.

(Greenland ice loss through 2016. Video source: NASA.)

With global temperatures now exceeding 1 C and with these temperatures likely to exceed 1.5 C within the next two decades, it is certain that broader heat-based stresses to these various glacial systems will increase. And we are likely to see coincident melt rate acceleration as more glaciers become less stable. The result is that coastal flooding conditions will tend to follow a worsening trend — with the most vulnerable regions like the U.S. Gulf and East Coasts feeling the impact first. Unfortunately, there is risk that this trend will include the sudden acceleration of various glaciers into the ocean, which will coincide with rapid increases in global rates of sea level rise. In other words, the trend for sea level rise is less likely to be smooth and more likely to include a number of melt pulse spikes.

Such an overall trend including outlier risks paints a relatively rough picture for coastal city planners in the 1-3 decade timeframe. But on the multi-decade horizon there is a rising risk that sudden glacial destabilization — first in Greenland and West Antarctica and later in East Antarctica will put an increasing number of coastal cities permanently under water.

Rapid Mitigation Required to Reduce Risks

The only way to lower this risk is to rapidly reduce to zero the amount of carbon hitting the atmosphere from human sources while ultimately learning how to pull carbon out of the atmosphere. The present most rapid pathway for carbon emissions reductions involves an urgent build-out of renewable and non-carbon based energy systems to replace all fossil fuels with a focus on wind, solar, and electrical vehicle economies of scale and production chains. Added to various drives for sustainable cities and increasing efficiency, such a push could achieve an 80 percent or greater reduction in carbon emissions on the 2-3 decade timescale with net negative carbon emissions by mid Century. For cities on the coast, choosing whether or not to support such a set of actions is ultimately an existential one.

Links:

Fragmenting Prospects For Avoiding 2 C Warming

NASA Antarctic Ice Loss

Scientists Just Uncovered Another Troubling Fact About Antarctica’s Melting Ice

It Wasn’t Even a Hurricane, But Heavy Rains Flooded New Orleans as Pumps Faltered

Why Seas are Rising Faster in Miami

Miocene Relative Sea Level

Temperature on Planet Earth

Ice Melt, Sea Level Rise, and Superstorms

Renewables Boom as China Halts or Eliminates Another 170 Gigawatts of Coal Power Plants

On Monday, China announced that it was halting or delaying another 150 gigawatts worth of new coal power plant construction through 2020. In addition, the world’s largest coal user also announced that it would eliminate 20 gigawatts of present coal burning capacity. These moves come on the back of China’s previous cancellation and closure of 103 coal-fired plants coordinate with three consecutive years of falling coal consumption from 2014 through 2016.

(China’s annual CO2 emissions primarily come from coal use. Rapidly reducing that coal use is essential to addressing global climate change. Image source: NRDC.)

According to the China News press release, the move was aimed at both avoiding overcapacity and ensuring a cleaner energy mix. China’s National Development Reform Commission went on to state that: “New capacity will be strictly controlled. All illegal coal-burning power projects will be halted.”

China alone burns about half of all the coal converted into carbon dioxide each year globally. So if the world is to effectively address climate change, then China’s massive coal consumption needs to start tapering downward. And the faster it does, the better things will be for us all. Outwardly, the country appears dedicated both to the notion of becoming a global climate leader while also working to address its serious air and water pollution issues. And to the latter point, China plans to revamp its existing coal plants in order to lower harmful particulate emissions. Digging a bit deeper we find that a worrisome high level of coal burning is slated to remain in place at least over the next decade. Even if the trend is moving in a generally helpful direction and even as renewable energy platforms popping up across China may enable the country to further cut its harmful greenhouse gas emissions.

(China’s coal targets through 2020 show continued steady reductions. Image source: NRDC.)

China’s move to halt or eliminate 170 gigawatts of coal burning follows a larger plan to keep total coal capacity below 1,100 gigawatts by 2020. How much below is still somewhat up in the air. But it’s worth noting that present coal burning capacity in China is 900 gigawatts and the best news for all involved would be if this capacity did not increase and that China’s rate of overall coal use continued to fall. This action is in keeping with a stated goal to reduce coal’s portion of the Chinese electrical power supply to 58 percent by the same year (down from 70 percent in 2010).

It’s a trend that follows major renewable energy build outs. A build that, taking into account China’s past economic over-achievements could accelerate to replace coal capacity at a faster than expected pace. Solar alone is well ahead of plan and is now expected to reach 230 gigawatts worth of capacity by 2020. Meanwhile, China is on track to have about 250 gigawatts of wind capacity installed by the same year. But there, too, an acceleration in off-shore wind capacity that could spike this number may also be in the offing. And as of August, China was selling about 45,000 zero-emitting electrical vehicles each month with a goal to have around 3 million EVs per year by 2020.

All serious trends that will, hopefully, further accelerate China’s rate of greenhouse gas emissions reductions. Given Trump’s various attempts to sabotage Obama’s positive legacy of climate response and renewable energy production here in the U.S., somebody in the world needs to take the role of global climate leader. Trump’s vacuous vision and overtly divisive nature has given China the opportunity to step it up.

Links:

China Halts Building Coal Power Plants

NRDC

Global and China Wind Turbine Industry Report 2016-2020

China’s Strict Electric Car Quotas

Intensifying Equatorial Rains: 3.3 Million Afflicted by Flooding in India and Bangladesh as Hundreds Lose Lives to Landslides from Sierra Leone to Nepal

There’s something wrong with the rain these days. For many regions of the globe, when the rain does fall, it more and more often comes with an abnormally fierce intensity.

This increasing severity of heavy rainfall events is just one aspect of human-forced climate change through fossil fuel burning. For as the Earth warms, both the rate of evaporation and precipitation increases. And as atmospheric moisture loading and convection increase coordinate with rising temperatures, so do the potential peak intensities of the most powerful storms.

(Climate and extreme weather news August 13 through 15)

Sierra Leone — More than 300 Dead, 600 Missing After Deadly Mudslide

This past week, in Sierra Leone — already one of the wettest regions of the globe at this time of year — a very heavy rainfall event generated a severe mudslide that ripped a huge swath of devastation through Freetown. 3,000 people were immediately rendered homeless by the great rush of mud, rock, and soil. But more tragically in excess of 300 people are feared dead with 600 still missing.

This single event represents the deadliest natural disaster on record for Sierra Leone — which also suffered a flood that killed 103 people in 2009. According to news reports, the region in which this disaster occurred has experienced 20 inches more rain than usual over the 30 day period from July 15 through August 15. A total amount of rainfall in a single month period that’s now in the range of 50 inches. Clearly, the surrounding lands could not maintain integrity under the force of such a prolonged deluge. And unfortunately one of the succumbing hillsides let loose into a valley settlement.

(Heavy thunderstorms of Freetown on August 14th. Image source: NASA and Weather Underground.)

A statement by Weather Underground’s Bob Henson provides further climate context for this disaster:

The heaviest downpours in many parts of the globe have become heavier in recent decades, a trend attributed to human-produced climate change and expected to continue. A study led by Christopher Taylor (UK Centre for Ecology and Hydrology), published this spring in the journal Nature, finds that the Sahel’s most intense mesoscale convective systems (organized clusters of thunderstorms) have tripled in frequency since 1982. The recovery of Sahel rainfall since the 1980s only explains a small part of this trend, according to the study authors. They argue that Saharan warming is helping to intensify convection within the MCSs through increased wind shear and changes to the Saharan air layer. “The meridional gradient is projected to strengthen throughout the twenty-first century, suggesting that the Sahel will experience particularly marked increases in extreme rain,” the study concludes.

Pradesh and Nepal Landslides and Floods Kill Over 100 More

Severe rains also on August 14th unleashed a mudslide in Pradesh India that knocked two buses off a cliff — resulting in the tragic loss of 46 lives. The resulting landslide also injured 5 other passengers even as it buried numerous homes along its path.

Across the Bay of Bengal in Nepal flooding and landslides resulted in the loss of 62 lives as 30 districts reported severe conditions. There, rains displaced 1,500 families, destroyed 305 homes, and damaged more than 15,000 other dwellings. Dozens of Nepali roads have been blocked, a school has collapsed, and an airport has been forced to close as severe storms inundated the region.

In India and Bangladesh, 3.3 Million People are Affected by Flooding

In the Indian state of Assam, 84 people have lost their lives due to a massive flood that has now affected 2 million people across 29 districts. 2,734 villages have flooded and 183,584 people have been forced to relocate to one of 700 refugee camps. Meanwhile, across the state, some 3,830 water rescues have occurred. Dozens of roads and bridges have been washed out as rivers rise from moderate to unprecedented flood stages.

(Assam floods on August 14. Image source: Government of India and Floodlist.)

Finally, in Bangladesh, record rainfall has pushed rivers to some of the highest levels ever recorded. The result has been the forced displacement of 368,000 people to 970 temporary shelters as 1.3 million are afflicted by flooding. Tragically, 27 Bangladeshis have also lost their lives due to the extreme flooding. Rainfall rates of up to ten inches per day are contributing to the severe flooding even as water from floods further upstream in India and Nepal are flowing into Bangladesh river systems.

Conditions in Context — Very Severe Equatorial Rains

Overall, these various events may appear to occur separately. However, they are all associated with a very severe Equatorial rain pattern developing from Africa through Southeast Asia and stretching into the Atlantic inter-tropical-convergence zone during 2017. The apparently increased thunderstorm activity is now impacting everything from the intensity of monsoonal rains over Southeast Asia, the severity of storms in the Sahel of Africa, and the early formation of tropical cyclones off Cape Verde during August.

These heavy rainfall features are arguably linked to the climate-change based intensification of the hydrological cycle and, particularly, to the increasing intensity of Equatorial thunderstorms. The overall climate and weather trend for the larger region should thus be noted and these various related events should not be viewed in isolation.

Links:

Weather Underground

Floodlist

NASA

Climate and Extreme Weather News

Hat tip to Shawn Redmond

Hat tip to Suzanne

No El Nino, But July of 2017 was the Hottest on Record. So What the Hell is Going on?

According to NASA’s GISS global temperature monitoring service, July of 2017 was 0.83 C hotter than the NASA 20th Century baseline (1.05 C hotter than 1880s). That’s the hottest July ever recorded in the 137 year global climate record.

In the Pacific, ENSO conditions remain neutral. And since 2014-2016 featured one of the strongest El Ninos on record, you’d expect global temperatures to back off a bit from what should have been a big spike in the larger warming trend. So what happened?

(Top image shows July of 2017 global temperature anomalies compared to July of 2016 global temperature anomalies [bottom image]. July of 2016 was cooling into a weak La Nina relative to one of the strongest El Ninos on record. This year, ENSO neutral conditions prevail coordinate with rather strong polar amplification in the Southern Hemisphere as temperatures in the Southern Ocean off West Antarctica hit an 8 C warm temperature anomaly [!!]. Images provided by NASA GISS.)

During July of 2016, the world was backing away from a very strong El Nino and heading into the mild global temperature trough of a weak La Nina. Cooler conditions in the Equatorial Pacific were starting to put a bit of a damper on the extreme global temperature departures that, earlier in the year, hit as high as 1.55 C above 1880s averages during February.

The La Nina lag during July of 2016 was enough to pull global surface temperatures down to 1.04 C above 1880s averages. However, the added heat pumped out into the system by both fossil fuel produced greenhouse gasses and the shift to strong El Nino appears to have generated a step change in the global temperature regime. So despite a weak La Nina dominating during fall of 2016, global temperatures remained in a range of 1.06 to 1.21 C above 1880s averages during August through December.

2017 Still Trending Toward Second Hottest on Record

Moving into 2017, overall global temperatures have backed off from the extreme heat seen during 2016. But only a little.

Adding in the record hot July at 1.05 C above 1880s averages, we find that 2017, so far is 1.16 C hotter than 1880s overall for the first seven months. That’s just 0.05 C shy of the record global heat that appeared in 2016. Not really much of a back-off at all.

July’s own record wasn’t a very impressive warm departure from 2016 — beating it by just 0.01 C. But what it does reveal is that there is an extraordinary amount of heat roaming the surface airs and waters of our world. And since all that extra heat will tend to resist cooling into Northern Hemisphere winter as it transfers poleward, we can probably expect that relative temperature anomalies will again rise as we move away from Northern Hemisphere summer. With departures likely continuing to exceed 1.05 or even 1.1 C above 1880s for most months going forward.

Already, early GFS model runs indicate that August of 2017 will likely be warmer than July. And this month might even come close to challenging the 1.21 C above 1880s averages achieved during 2016. However, using GFS global averages as an indicator is not a perfect oracle. So we wait on the August numbers from GISS and NOAA a month from now for final confirmation.

Furthermore, we do have a relatively weak cool Kelvin wave rippling along beneath the Equatorial Pacific at this time. This wave should shift the ENSO pattern to the cool side of neutral by Northern Hemisphere fall. A pattern that should also tend to nudge overall global temperatures downward. Recent falls in the north, though, have tended to exhibit very extreme polar warming. And a similar trend this year would tend to offset any Pacific Equatorial cooling. Lastly, the cooler ENSO neutral pattern is likely to still be a warmer general forcing than the weak La Nina that appeared during late 2016. So there is at least some potential that some months during fall of 2017 will be warmer than those during fall of 2016.

Considering these trends, the best available predictive analysis from NASA shows that 2017 is likely to be about 1.1 C warmer than 1880s or the second hottest year on record globally overall. NASA’s Gavin Schmidt gives this range a 77 percent likelihood of bearing out. But note the error bar in Gavin Schmidt’s above tweet. In other words, the presently far more unstable climate appears to be quite capable of serving up some relatively nasty surprises.

Links:

NASA GISS

NOAA ENSO Forecast and Analysis

Global and Regional Climate Anomalies

Hat tip to Redsky

Hat tip to Joe Romm

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