Hothouse 2090: Category 6 Hurricane A Grey Swansong For Tampa

Tampa. 2090. Late September.

The stiff wind running off the Gulf of Mexico felt like a blast furnace. Ocean surface temperatures near 100 degrees Fahrenheit; air temperatures of 113 F, high humidity, and a smell like rotten eggs added to the overall insufferability. Unpleasant was a better word from a better time. Mere unpleasantness had long since fallen away before the new deadly edge that Nature had adopted.

Tampa’s streets were packed with vehicles but featured only the rare transient foot and bike traffic. Just 15 minutes’ exposure to the brutal four p.m. heat and humidity could swiftly result in heat stroke as a body’s natural cooling systems were overwhelmed by conditions no human physiology could for long endure. The city had long since grown accustomed to the warnings. Anyone wanting to stay healthy remained indoors, huddling close to the blessed vents blasting machine-cooled, filtered air.

In the heat-scorched streets, elevated many times over to keep above the rising seas, a few diehards still roamed. They sported the latest in cooling accessories — thermal-bleeding fashions were all the rage and had been for at least three decades now. So too were the thin-film sulfur filtration masks, totem-like in their branding and individually styled in patterns of iridescent colors. These were the stylized provisional responses to the gigantic dead zones that regularly painted the Gulf’s waters purple-black with stinking, toxic-gas-spewing bacteria. But today, the waters were sickly green. The stink was merely unbearable and only somewhat unhealthy, thanks to the large and powerful storm now pushing in the bluer off-shore waters and flushing out some of the seaside dead zone.

RCP 8.5

(Under RCP 8.5 warming scenarios, the Earth is transformed into a hotter, more deadly place, capable of supporting storms of never-before-seen intensity. Image source: The European Environmental Agency.)

Great swells churned away – covered in gooey sludge. Some residents thought fondly of the December- to-February tourist season when temperatures fell, the waters cleared and, at times, swimming was safe. But such thoughts were quickly blasted away by the constant warnings now blaring through the local radio. Hot waves capped with frothy green foam were already roaring over the shoals of the old seaside districts and barrier islands before slamming into the defensive ring of sea walls. Ice melt in Greenland and Antarctica had long since forced a retreat from the bay and ocean, pushing an eight-foot rise in sea levels over the 90 years. The near-water residences, once premium real estate, had long since been relegated to tourist homes or the odd air and ocean monitoring station

Tampa Reeling in a Dangerous Climate Zone

Tampa had fared badly, but not so badly as Miami, or the huge chunk of South Florida now covered up by the Gulf and Atlantic Ocean. In the 2030s, large numbers of South Floridians and coastal residents began an exodus northbound and inland. Some stopped in Tampa, staking a claim on the increasingly-expensive higher elevations, but most just kept heading north — past drought-stricken Georgia, through the drying Mid-Atlantic states, and on north, even into Canada. But anywhere they went, there were problems. A big zone from the Mid-Atlantic on south and west was turning into desert. The Mississippi was becoming more and more an intermittent river –practically drying up most summers and then flooding like the dickens during February through April as gigantic storms cycle south out of the Arctic, driving massive swaths of hurricane-force winds before them. The West was even worse, with a large section of four states now experiencing temperatures that make early-century conditions at Death Valley seem tame.

It was tough to find a place of safety and security, much less comfort. Lives were shorter, harder than ever before. People scrambled from place to place. They hoarded food. Most were thin — Renaissance-era voluptuousness was making a comeback. Indoor and underground farming had exploded — saving the lives of millions in the parts of the world that adopted these methods — but the dead oceans, lost farmlands, and increasingly scarce fresh water sources resulted in a cascade of regional and global crises. Needless to say, there were less people. There was basically less of anything living anywhere. All the heating and burning and storming and putrefying had seen to that — the results of two centuries of fossil-fuel emissions that ebbed and flowed but never really stopped growing.

Tampa, like every other city still functioning, had seen her fair share of all this trouble. She was one of the lucky ones — still around, clinging to the higher elevations, still building up her sea walls, making and importing what food she could, finally casting off the corrupt fossil-fuel industries and enabling what economy that remained through all-renewable energy. You couldn’t call it sustainable — that ship had long since sailed. Some day, a big glacial outburst flood somewhere in Antarctica would push seas high enough to devour Tampa whole. Or some day, a giant city-killing storm could scour enough of Tampa from the face of the Earth that the resources and effort necessary to recover would simply become a mountain too high to climb.

Haiyan enhanced

(Under the hothouse-warming scenario that is RCP 8.5, hurricanes will have the potential to substantially exceed the strength of supertyphoons like Haiyan [enhanced satellite image above] which devastated the Philippines. Image source: NOAA.)

Category 6 Hurricane Raptor Sets Sights on Tampa

For Tampa, that day may well be the day after tomorrow, for monster storm Raptor now tore through the blue, green, and purple-black waters of the Gulf of Mexico. Gorging on sea-surface temperatures near 100 F, this enormous stack of lightning-wracked clouds reached 80,000 feet into the atmosphere. It ripped that hot air and moisture up from the surface, casting it in an enormous bellow toward space. In the wall of the resulting funnel, winds howled at 230 miles per hour. Minimum central pressures measured 835 millibars. Wave-height measures from some buoys — those whose sensors hadn’t been slammed into inoperability — were coming in at 100 feet.

A 20-mile-wide swath of these conditions formed an atmospheric axe along the right front quadrant of the storm as it turned toward Tampa. Crossing land, it would produce a 35-foot storm surge topped by 20- to 40-foot breaking waves. In areas not submerged by these churning, toxic waters, the winds would blow as strong as an EF 5 tornado — enough to strip the bark from trees. This combination of conditions would demolish any above-ground structures. The cone of destruction centering at the coast, then ripping 60 to 100 miles inland before the storm finally slaked its rage.

Taller Storms Climate Change

(Increasing global temperatures enlarges the zone in which storms can form, heightening cloud tops. Taller warm-air updrafts more heavily laden with moisture increases storm potential energy. In this way, climate change increases top potential storm intensity. Overshooting cloud top image provided by: Commons/NOAA.)

Similar nasty storms had helped to render the Persian Gulf region uninhabitable. Cairns, Australia had been ripped apart by such a beast five years earlier. The Phillipines, Taiwan, coastal China and Japan were visited ever more frequently by the monster category 4, 5, and 6 systems. And the thing barreling toward Tampa was among the strongest of a deadly new breed that meteorologists were now calling city killers.

The threat was not lost on residents. Those unresponsive to storms and extreme weather didn’t have a very high life expectancy. Roadways leading out of Tampa became packed with traffic. Inbound lanes were designated outbound. Trains, planes, hyperloops, and buses were all packed to the gills with those fleeing the path of Raptor. Lower populations after the migrations and mid-to-late Century crashes, in part, made the flight easier. As did the increased responsiveness. But the size of the storm swath, lower road and track resiliency due to the heat ahead of the storm, the more toxic air blowing off the ocean, and the increased population densities due to suburban abandonment created its own evacuation nightmares.

Higher populations of older persons suffering from increased rates of dementia and frailer organ systems due to toxin accumulation and disease proliferation were also less mobile. Moving this vulnerable group required a major effort on the part of Tampa volunteers and emergency responders. But after suffering decades of increased losses, lives and personal relationships were often considered all-the-more precious as people nostalgically clung to what connections remained or fought a crushing sense of fear and isolation by increasingly working to help others. The great ages of excess that preceded this period had left deep and enduring marks on the psyches of the people who’d survived through those times. And a quiet, defiant, never-again mentality had begun to emerge. In the face of such loss of beauty and safety, people were not only determined to live, they were determined to make the most of what meager lives remained to them by caring. By adding art and color to a world increasingly denuded of beauty. And by, most of all, attempting to preserve life.

The flight of Tampa’s populace from before the storm was, therefore, far more responsive, far more vigorous, than the responses of previous generations. And a vast majority heeded the warnings and left. As a result, the city became an empty shell with only about a hundred thousand die-hards and emergency personnel remaining.

With the big evacuation pulse now running inland and northbound, and with sections of Orlando evacuating while other portions hunkered down, the first outliers of Raptor began to encounter the coast. The green-white froth on the swells grew more vivid — almost looking neon in the light of dawn. Off-shore, an angry black stack of clouds thrown off from Raptor’s outer bands rushed toward shore. Gale-force gusts and a large accompanying swell pummeled Tampa’s seawalls and streets. The down-drafts and the first falling rain drove temperatures lower — into 90s (F). But the sensation was still one of oppressive heat due to the near 100 percent humidity.

The Storm Rushes In

Winds continued to rise and, over the next few hours, hot, driving rain steadily wrapped the Tampa region in a kind of stinking, hissing, steam. The continuously lifted sea walls and dikes never quite kept up with sea level rise. So even the early outliers of Raptor were enough to generate floods of putrid, green waters rushing through the lower-lying streets. Bridges and roads were quickly cut off and those remaining in town, and especially those on the newly dubbed Petersburg Island, were quickly cut off. Those poor souls remaining would have to face Raptor on their own and without the aid and comfort of an increasingly necessary emergency response force.

Current Tampa Bay Topographical Map

(Current Tampa Bay topographical map provided by the US Geological Survey. Under the 8 feet of sea level rise by 2090, most of the green sections would be below sea level. 8 feet of sea level rise plus 35 feet of storm surge plus 30-40 foot breaking waves would generate flooding in event some of the higher elevation areas [orange to brown]. Note that elevations in the map above are listed in meters. Image source: USGS.)

Raptor was moving rather swiftly and by early evening the storm’s eye wall was beginning to approach the coast. Off-shore, a great mound of water like a tsunami ran up from the waters of the shallow Gulf. Still taller waves rose atop it. Some of the rogue peaks stretched 150 feet above the base sea level. The net effect was one of an intense green-white mass taller than the tops of most buildings roaring in from the Ocean. The mass drowned St. Petersburg in a foundering break-water. It roared into Tampa Bay, and there it lifted the remaining ships and boats and hurled them bodily into buildings, across the shore line, and into rapidly flooding streets. Waters rushed into Tampa and on inland — in some places continuing for 10-20 miles before the great pulse of water was finally slaked by elevation.

Southwest winds rose up into a sound like a freight train. Debris was hurled into a great cloud over the flooded city. Everything from bits of sand and dirt, to paint chips, to flinders of bark from the few hardy trees remaining, to as large as vehicles and wall sections was lifted and hurled with lethal force. The churning vortex of 150 to 230 mph winds created a wall of moving air full of this shrapnel. Tampa was engulfed in a loud and angry blackness full of giant waves and flying teeth. In the above-water sections, it was impossible to see more than 10 feet outside clearly. And tens of thousands of structures were quickly ground down to their foundations by the combination of violent water and air.

These conditions covered a region stretching for 20 miles along the coast. With Raptor making landfall near Largo, this swath covered the mouth of Tampa Bay, St. Petersburg, Lealman, and Pinellas Park. With the storm running across the northern bay to make a second landfall about ten miles south and east of Safety Harbor, most of Tampa proper was affected by this zone. The raging storm surge, concentrated by the Bay and pulled along the arch of the storm’s vortex peaked to extreme heights where the bay narrowed into Tampa. And large sections of the nearby city simply drowned.

Then the storm passed inland, dumping torrential rain and cutting an 80 mile long, 20 mile wide swath of destruction through Central Florida. The wall of airborne shrapnel picked up more and more debris as it went. A few travelers on the road were forced to hunker down at a nearby recharging station’s convenience store — which subsequently collapsed. Their ordeal, recorded by portable devices which caught the hours-long images of flying cars, bits of transmission towers and other debris so damaged as to be rendered into an unrecognizable black grit across the sky, became a part of one more ‘new most violent’ storm record. A testimony to the worsening hazards and losses of the time.

As the next day dawned and rescue and disaster relief aircraft entered the storm zone, the epic destruction was more fully revealed. Observers from airplanes pointed out the swirling impressions upon the stripped land. One pilot noted that it looked like a thousand tornadoes had all gotten into a line 20 miles long and then run north and east inland. Another simply stated that it looked like the land had been pounded barren by the vast fists an angry god. Over a million structures had suffered at least moderate damage. Over 200,000 had been blown or knocked by waves down to their foundations. Despite the effective evacuation, the death count was tremendous. More than 35,000 in the Tampa region and points inland immediately lost their lives to the storm. Another 60,000 were estimated to have perished in the aftermath as a failure to restore power in time resulted in exposure to killing heat and near-shore airborne toxins. Considering comparable storm, fire or drought losses in three other US cities that year and the inevitable coming multi-meter sea level rise, government officials decided to add Tampa to the growing list of communities that would never be rebuilt.

Conditions in Context – Global Warming Increases the Top Potential Strength of the Most Powerful Storms

In 2016, Earth’s atmosphere isn’t yet capable of producing a storm like Raptor. But in a not-too-distant future, a 5-degree (Celsius) rise in global temperatures pushed on by 900 parts per million of atmospheric CO2 would result in heightened levels of heat and moisture fueling a great deal of instability. The Earth’s atmosphere would still be taking in huge amounts of heat at its top. The glaciers would likely be unzipping and sending out hordes of icebergs riding a pulse of cold surface water. As ever-more-dominant heat goes to war with dying cold, the amazing temperature differentials spawn equally terrible storms.

Seventy-four years from now, under business as usual warming scenarios, the tropics and subtropics are likely to be hundreds of miles to the north of their current geography. Rising troposphere heights will bring ever-taller thunderstorms. When these storms manage to organize into hurricanes, the results have the potential to be dramatically more powerful than today’s comparatively tame storms. Category 3, 4, and 5 storms would be more frequent. And a new category — 6 – may be needed for storms whose maximum sustained winds exceed a range near 200 miles per hour and whose minimum central pressure hits lower than around 880 mb (a range that starts out a bit more powerful, on balance, than the strongest storms that are capable of forming today).

Links/Statements/Attribution

The above scenario is a climate fiction portrayal of a potential category 6 hurricane impacting Tampa in the 2090s. The scenario incorporates recent scientific studies pointing toward projected increases in hurricane intensity due to human-forced warming of the Earth’s oceans and atmosphere. In particular, the work of Dr. Jeff Masters on emerging Grey Swan hurricanes driven by climate change proved very helpful in providing a groundline basis for potential category 6 hurricane strength and impacts. And it is worth noting that Dr. Masters is highlighting scientific work showing that under business as usual human warming it is possible that storms of never-before-seen intensity will hit the Tampa region.

The storm in this scenario, Raptor, is nearly as strong as the storm produced by one of the climate models Dr. Masters references. This extremely powerful storm hit Tampa in a physical computer model assessing hurricane strength under business as usual warming. The modeled storm achieved 235 mph maximum sustained winds and an 830 mb minimum pressure. It’s worth noting that we have no record of a storm of this strength ever forming on Earth. But, under greenhouse gas loads and temperatures that continued fossil fuel burning will establish by the end of this century, the Earth atmosphere becomes capable of supporting such extreme events.

To this point, it is absolutely also worth referencing Dr. James Hansen’s seminal Storms of My Grandchildren while making the very clear statement that the atmospheric brew we are pumping out will make never before seen monster storms a terrible and dangerous aspect of the world our children and grandchildren will inherit and try to survive in.

Tampa Bay Florida LANCE MODIS

(Tampa, Florida, seen in the center of this July 2016 satellite image, is currently one of many cities facing serious threats posed by human-caused climate change. Whether Tampa or any of these other cities survive depends on how well human beings respond and on how much we lessen the coming damage by reducing fossil fuel emissions now. RCP 8.5 is a bad climate scenario. The only problem is that all we have to do to get there is simply continue to burn oil, gas, and coal. Image source: LANCE MODIS.)

The scenario also takes into account various broader Earth System changes such as potential sea level rise due to melting glaciers, increased disruption of food and water supplies, loss of ocean health and increased anoxia and related water and local air toxicity (due to warming and increased nutrient run-off into the world ocean), model simulations and understandings of the increasing prevalence of extreme land and ocean surface heat and 2 meter humidity (wet bulb temperatures increasing into the lethal range of 35 C+), and expanding drought, disease and extreme weather zones.

This particular event and context follows closely to conditions projected under the IPCC’s business as usual fossil fuel emissions or RCP 8.5 warming scenario. For the purpose of this exercise, I have added climate conditions to the business as usual case that I see as plausible given that level of warming. Some of these additions are based on my own interpretation of scientific efforts that are currently not fully settled. However, I feel the overall portrayal is likely at least relatively accurate given various model projections and how the Earth System appears to have changed in response to past warming events.

It’s worth noting that RCP 8.5 does not assume zero renewable energy adoption. It simply assumes that fossil fuels will remain the dominant source of energy with consumption growing through the end of the 21st Century. As such it results in a catastrophic warming scenario over a less than one century time-frame. But such a warming would be achieved over longer time-frames so long as human carbon emissions are not rather swiftly brought to zero, Earth System feedbacks are strong enough, or elevated atmospheric greenhouse gas levels are not drawn down. Conditions similar to RCP 8.5 at 2100 could be achieved by approximately 500 ppm CO2 by around 2500. A reality that increases the necessary urgency of our current mitigation responses. Lower level warming and emissions scenarios are still dangerous, but do not result in the higher levels of harm evident in RCP 8.5.

Human impacts in the scenario such as loss of lives and lifespan reduction are based on my own understanding of how human beings are likely to adapt to such situations and how multiplied environmental stresses are likely to start to overwhelm human population growth in net by middle-to-end Century under the RCP 8.5 scenario. The writing above assumes that the civil system surrounding Tampa and this section of the United States remains at least partially intact due to cooperative effort on the part of individuals living in society at the time. Such a response is hopeful, but it is not guaranteed.

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Rapid Polar Warming Kicks ENSO Out of Climate Driver’s Seat, Sets off Big 2014-2016 Global Temperature Spike

“What is happening right now is we are catapulting ourselves out of the Holocene, which is the geological epoch that human civilisation has been able to develop in, because of the relatively stable climate. It allowed us to invent agriculture, rather than living as nomads. It allowed a big population growth, it allowed the foundation of cities, all of which required a stable climate.” — Stefan Rahmstorf

A strong El Nino in 2015 helped to contribute to record hot global temperatures over the past three years. But with so much heat unexpectedly showing up in the global climate system, there’s clearly something else going on. And indicators are that the natural climate variability that human beings have grown accustomed to over the last 10,000 years may now be a thing of the past — as it is steadily overwhelmed by a stronger overall greenhouse gas based warming signature. One that is concentrating more and more warming near the poles.

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2014 was the hottest year on record. But that lasted only until the end of 2015 — which shattered the 2014 global heat record by a big margin. Then 2016 rolled around and produced what could best be described as an insane heat spike during the January through May period. Now, it’s about 95 percent certain that the 2015 record will also fall, leaving 2016 as the new hottest year on record in yet one more climate vertigo inducing temperature jump.

noaa-jan-may-temps

(The rate of warming for 2014 through 2015 is just off the charts. This scares scientists, and it should. This makes many climate experts wonder about causes, and it should. Prime suspect for the increased rate of change — amplifying feedbacks in the Arctic. Image source: NOAA Global Analysis and Weather Underground.)

In the end, temperatures are expected to level off near 1 C above 20th Century averages and around 1.2 C above 1880s averages by the end of this year. That’s a 0.3 C leap up since the mid 2000s. A screaming rate of decadal warming that is about twice as fast as that experienced since 1979. That’s an insanely fast pace of heat build-up. And it’s got many scientists seriously concerned. The records, as the Guardian aptly notes, were not just broken, they were obliterated. Adam Scaife, a scientist at the Met Office in the UK, agrees:

“The numbers are completely unprecedented. They really stick out like a sore thumb… Including this year so far, 16 of the 17 warmest years on record have been since 2000 – it’s a shocking statistic.”

So what the heck is going on? We know that a strong El Nino just passed. But, though a real beast of a thing, the 2015-2016 event wasn’t quite as powerful as the 1997-1998 El Nino. And global temperatures will end up being about 50 percent hotter than 1998 averages by the end of this year. Essentially leaving this great El Nino’s heat spike in the dust. Meanwhile, scientists attribute about 1/5th of the 2014 to 2016 heat spike to El Nino. The rest came from someplace else. But where?

The first obvious suspect is greenhouse gasses. In 1998, atmospheric CO2 levels peaked at around 365 parts per million at the Mauna Loa Observatory. This year, that heat trapping gas hit near 408 parts per million in the same measure. That’s a 43 parts per million jump peak to peak in just 18 years. A 12 percent increase in a gas that is capable of causing severe geo-physical changes in what, geologically speaking, is not even a blink of an eye. And you have to go back millions of years into Earth’s history to find times when CO2 readings were so high.

So the big build-up of heat trapping gasses is the obvious driver of the overall insane rate of warming that we are now seeing. But that doesn’t account for what is an unexpected acceleration over the past three years. And to puzzle out that speed-up we need to dig a little deeper. To consider factors that are known as amplifying feedbacks.

And, thankfully, in this investigation, we are not flying completely blind. NASA and the other global climate monitors give us a rough global overview of where the Earth is warming up the fastest. And an investigation of comparable temperature anomalies at the Earth’s surface can give us some indication where the extra heat is coming from and why.

1997 — Some Polar Amplification (aka Death of Winter), But Mostly Equatorial Warming

The obvious choice is to pick two relevant years for comparison. And for our purposes we’ll pick 2015 and 1997. The reason for this pick is that both 1997 and 2015 were years in which strong El Ninos were building up and having their impact on the global climate system. And based on what we know about El Nino, we can expect a lot of heat coming out of the Equatorial Pacific as sea surface temperatures there ramp up. In a climate system that is only driven by a natural variability related El Nino, what you’d expect is that the primary heat spike would be in the Eastern Equatorial Pacific region. Any other heat spike would be a possible indicator of another climate driver for global temperatures.

1997 Temperature Anomaly

(1997 may have been the last year in which a big El Nino still maintained a tenuous grip as the primary driver for the global climate system. Image source: NASA.)

So for the year of 1997 (Jan-Dec) we find that a strong heat pulse does originate from the Eastern Equatorial Pacific region. In fact, it’s the largest zone containing temperature anomalies in the range of 2 to 4 C above average. But during this year we also find some pretty big anomalies in Central and North Asia. These flow across the Bering Sea into Alaska, Northwest Canada, and the Beaufort. High Arctic temperatures are somewhat cooler, though still anomalously warm. And West Antartica also shows its own, not insignificant temperature spike.

Given the fact that El Nino will tend to strengthen the Jet Stream and generate a warming bias in the tropical zones, we can already see that there’s probably some polar amplification going on in 1997. And overall, the northern polar zone from 66 North to 90 North shows a positive anomaly signature that is just 0.1 C shy of the equatorial anomaly produced by El Nino. But the heat signal between El Nino and Northern Hemisphere polar amplification appears to be more balanced, with El Nino still providing a slightly stronger share of the overall heat contribution.

Understanding Polar Amplification’s Impact Due to Global Warming

For reference — polar amplification is an expected more rapid increase in polar temperatures as global greenhouse gas concentrations increase. Under pressure from greenhouse gasses, the poles warm faster for a number of reasons. The first is due to albedo or reflectivity loss as ice melts. White ice changing to brown earth or blue ocean due to melt absorbs more sunlight and creates a preferential warming at the poles. In addition, greenhouse gasses (especially CO2) capture and re-radiate sunlight’s heat energy like a blanket. As a result, temperatures tend to homogenize more over the globe resulting in a greater rate of temperature increase where it’s coolest and darkest. And the poles are the coolest and darkest places on Earth.

A third cause of polar amplification involves added heat resulting in natural carbon store release. And some of the greatest concentrations of the world’s sequestered carbon stores are locked in frozen ground and water at or near the poles. If ice at the poles thaws, you tend to end up with a higher overburden of greenhouse gasses in these regions. This is particularly true in the Northern Hemisphere where large regions of permafrost and ocean carbon stores are more vulnerable to release from early warming than the deeply sequestered stores in Antarctica.

(Dr. Jennifer Francis’s observations on Jet Stream weakening and polar amplification have big implications both down [Pole] and up [Equator] stream.)

Finally, as the polar zones warm up, they tend to generate weaknesses in the circumpolar Jet Stream. This is due to the fact that temperature differences between pole and tropics drive both Jet Stream speed and strength. As the relative difference drops off, the Jet Stream slows. And when the Jet Stream slows it meanders — creating big troughs and ridges centering on the middle Latitudes but sometimes extending all the way up to the poles. In the ridge zones, warm air is able to drive further north or south. And this feeds polar amplification by linking hot Equatorial air masses with the Pole itself. Over recent years, high amplitude Jet Stream waves have become a regular feature of the global climate system and have been associated with numerous extreme weather events — some of the most notable being the Russian Heatwave and Pakistan floods of 2011 and the anomalous late December 2015 warming of the North Pole above freezing.

2015 — Polar Amplification in the Driver’s Seat

By 2015, the polar amplification signature, especially in the Northern Hemisphere, started to look ridiculously strong.

2015 El Nino Polar Amplification

(2015’s picture of Polar Amplification during an El Nino year should disturb anyone who knows anything about how global climate systems should work. Image source: NASA.)

And during this year we find that the zone of greatest temperature anomalies lies not over the Equatorial Pacific — but over the high Latitude regions of the Northern Hemisphere. 2-4 C above average temperatures dominate a huge zone stretching from North Central Asia and Europe and on up to the North Pole. A similar zone dominates Northwestern Canada, Alaska and the Beaufort Sea. And pretty much the entire Northern Hemisphere Polar and near Polar zone falls under 1-4 C above average temperatures for the year.

By comparison, the Eastern Equatorial Pacific appears to play second fiddle to the Polar and near Polar heat build up. A broad region across the Central and Eastern Equatorial Pacific does see 1-2 C above average temperatures, with a small pool of 2-4 C deltas off South America. But it’s not that much greater a signal than a significant heat pool over the Indian Ocean. And the Northern Hemisphere near Polar zone is altogether the area that’s clearly the global heat center of gravity. An observation bearing out in NASA’s zonal anomaly measure which finds that Latitudes  66 to 90 North were about 1.6 C above average and the highest relative temperature anomaly zone on the planet. Meanwhile, the Equator lags at +1.2 C above normal. That’s a relative Equator to Pole anomaly change of +0.5 C from El Nino years 1997 to 2015. An indicator that El Nino may no longer be the primary driver of the global temperature and climate engine. And that its overall role is greatly diminished over the 1997 to 2015 timeframe. And, finally, that a greenhouse gas based warming polar amplification signature is now in the driver’s seat.

So, basically what we have during an El Nino year is the pole warming relative to the Equator and under any condition other than human forced climate change — this is something that definitely should not happen. In other words, you’re not in Kansas anymore and Kansas isn’t on Earth anymore. At least the Earth that human civilization is used to. For what we’re experiencing is the climate of a planet that is definitely not operating under Holocene norms — but under the transitionally destabilizing forces of greenhouse gas based warming.

Warm Air Slots and The Death of Winter

So in comparison to 1997, it appears that during 2015 the Northern Pole gained heat very rapidly (increasing by +1 C over these 18 years) while Equatorial heat continued to build (adding +0.4 C over the same period). In other words, Polar warming was about 2.5 times faster than Equatorial warming during the 18 year interval. The result is that by the El Nino year of 2015, the Pole showed dramatically higher relative global temperature anomaly spikes. This, in a few simple words, is the evidence of a greenhouse gas warming based polar amplification writ large. But digging down into the details a bit more we find a number of further disturbing clues as to what’s really going on in the grinding gears of our global climate machinery.

September of 2015's Crushed Polar Vortex During a Spiking El Nino is a Bad Sign

(September of 2015’s crushed polar vortex and high amplitude Jet Stream wave patterns during a peak period of Equatorial heat known as El Nino is a bad, bad sign. A clear indication that polar amplification is starting the drive and destabilize the global climate regime. September 10 of 2015’s Northern Hemisphere Polar reference Jet Stream capture is by Earth Nullschool.)

The first is the appearance of a big warm air slot running directly from the Equatorial Pacific over the Eastern Pacific and North America and on up into the Northern Polar zone. Here we find the signature of 2015’s ridiculously resilient ridge (RRR) pattern in the NASA global anomaly map for the year. Warm air consistently funneled directly from the Equator, was drawn through the high amplitude ridge (see Dr Francis’s video above) and pulled into the polar zone.

But the RRR zone wasn’t the only big warm air slot pulling air north during 2015 — just, perhaps, the most obvious. A second big warm air slot appeared over the Eastern North Atlantic, Western Europe and extended to cover most of Asia. And this enormous Equatorial air sucking beast really ramped into high gear during late December of 2015 when it drove North Pole temperatures above freezing.

QBO Gravity Wave

(Upper level Equatorial zonal winds all peaked at the same time during September of 2015. A sign that Equatorial heat went north in a manner that produces some potentially bad implications for Northern Hemisphere Winter under a regime of human-forced climate change. Image source: Anthony Masiello.)

Taken in total, these warm air slots were enormous — exerting an amazing influence over the totality of global weather. The overall story is one in which the polar vortex was basically getting smashed during an El Nino year. Another big indication that things are teetering pretty far off kilter. One indicator of this was an anomalous spiking of all the upper level Equatorial wind speeds at the same time (in the Quasi Biennial Oscillation measure) during September of 2015. An event that current climate theory says shouldn’t happen, but it did. And yet one more hint that the Hadley Cell produced a huge northward bulge at the time. It’s also an indicator that Northern Hemisphere Winter is getting steadily beaten back to the ropes by the bully of northward running heat.

So what we’ve seen from 1997 to 2015 is a dramatic transition in which El Nino appears to have lost climate influence powers and become a slave to what is now a heat-sucking engine at the pole. It’s an emerging first phase of a death of winter type scenario. And the upshot is that the extra heat in the system that scientists are getting pretty concerned about appears now to be coming in large part from a ramping Northern Hemisphere polar amplification.

Links:

NOAA Global Analysis

NASA GISS

NOAA and NASA — Earth’s Warmest May on Record

Dr Jennifer Francis on Polar Amplification and the Jet Stream

Anthony Masiello

Quasi Biennial Oscillation

Earth Nullschool

Shattered Global Temperature Records Reveals Climate Change Emergency

Scientific hat tip to Dr. Jeff Masters and his best-in-class Weather Underground

Scientific hat tip to the prescient Dr. Jennifer Francis

Scientific hat tip to Dr. Stefan Rahmstorf

Scientific hat tip to Adam Scaife

Hat tip to Greg

Hat tip to Colorado Bob

Hat tip to Cate

Hat tip to DT Lange

 

 

A Blizzard Roars Out of Climate Change’s Heart — Polar Warming and A Record Hot Atlantic Ocean Brew Up Nightmare Storm for US East Coast

There’s a historic blizzard in the form of Winter Storm Jonas setting its sights on the US East Coast. The storm is slowly coming together Thursday evening and now appears to be set to paralyze a 1,000 mile swath under 1 to 2.5 feet of snow even as it hurls a substantial storm surge and 40-60 mph winds at waterfront cities from Norfolk to Boston. A monster storm whose predicted formation has made headlines since Tuesday. But what you won’t hear most major news sources mention is the likelihood that this gathering storm has been dramatically impacted by a number of new climate features related to a human-forced warming of the globe.

Jonas Begins its Ocean-heat Fueled Rampage in Southeastern US

(Jonas begins its ocean-heat-fueled rampage on the evening of Thursday, January 21. Image source: NOAA.)

A Warming Arctic Shoves the Cold Air Out

To understand how climate change helped make Jonas so extreme, it’s best if we start our tale in the Arctic. For if we could mark an area on the Earth’s surface that is at the very heart of impacts for human-caused climate change it would be in that zone of the far north above the 66th parallel. It is there that we see the most dramatic, most rapid changes — to ice, to weather, to the thawing lands, to life itself. But unlike what might be said of an American city made famous by its penchant for sin — what happens in the Arctic doesn’t stay in the Arctic.

This is especially true when it comes to weather. If the Arctic cools, it influences the Jet Stream, strengthens the storm track and shuts more cold air away in the Arctic. But if the Arctic warms, as it has more and more frequently during recent years, then the flood-gates open and cold, Arctic air pours outward — filling the deep, inevitable dips in the Jet Stream that then develop.

And it is a massive accumulation of Arctic heat over the past few weeks that has forced Arctic temperatures, in places, to rocket to above 36 degrees Fahrenheit (20 degrees C) warmer than average. A heating up of the entire region to 2-3 degrees Celsius warmer than the already warmer than average 1979- 2000 baseline. An Arctic warm-up that muscled out a howling torrent of cold air that then raged on into a deep trough in the Jet Stream now forming over the eastern half of the United States.

Hot Arctic, Cold, Stormy Eastern USMangled Jet Stream, Raging Storm Track

(An Arctic that is, on average 2.02 C hotter than normal on Friday joins with a high amplitude wave in the Jet Stream and together drives a massive flood of cold air into eastern parts of the US on Friday. Cold air slamming head on into unprecedented heat and moisture bleeding of the Atlantic Ocean to form the historic weather event that is now in the pipe. Image source: Climate Reanalyzer.)

CAPE — Storms Fueled by Cold Colliding With Hot

In weather parlance, a trough, or a big dip in the Jet Stream is a storm generation zone. The reason has to do with the nature of how extreme differences in temperature and moisture can provide fuel for strong storms. It’s this very temperature differential that sits as the cornerstone of our current understanding of how extreme storms are fueled in terms of Convective Available Potential Energy (CAPE).

In the one case, cold air can’t hold as much water in suspension as warm air. So a big flood of cold air can often fuel major precipitation events when coming into collision with hot, moisture-laden air. As hot and cold air are sandwiched closer together, winds — at both the upper and lower levels — tend to increase in velocity. The higher the difference in temperature, the stronger the winds. When these winds run along a big dip in the Jet Stream — like the one now racing over the US East Coast — they can spin off twists and vortexes that can rapidly develop into powerful low pressure systems.

The lows then feed on the difference in temperatures between the two sides of the dividing air-mass — cold on the one side, and hot, wet on the other. The bigger the differential, the more heat and moisture on one side, and the more cold on the other side, the more potential that such low pressure centers will develop into monster storms. The more potential that the storms will develop these crazy atmospheric sandwiches of hot and cold air that really crank out the extreme weather.

Dulles International Airport 5 inch per hour thundersnow potential identified

(“Tremendous Vertical Motion.” Anthony Sagliani tweets about extreme CAPE for a blizzard zeroing in on the US East Coast. What’s important to mention is that human-forced climate change has CAPE written all over it. Image source: Anthony Sagliani.)

In terms of the current storm, some of the CAPE potentials coming in are just off the charts. The above graphic, posted in this recent tweet by Anthony Sagliani, identifies the potential for 5 inch per hour thundersnow at Dulles International Airport (AID) between 2 AM and 2 PM Saturday. To be very clear, a 1 inch per hour snowfall was once considered an extreme event. Now we are looking at possibly 5!

A Record Hot Atlantic Feeds it All

In the context of human-driven climate change, this is one of the reasons why our warming up of the world can generate extreme weather. It warms the Earth unevenly. It puts cold next to hot by driving cold out of the polar zones and by warming up huge areas of land and ocean. And it dumps more moisture into the atmosphere through an amplified evaporation from these greatly warmed Earth surfaces. Mix it all together and you get Anthony Sagliani’s ‘tremendous vertical motion.’

How does this work? In two words — latent heat. More specifically the convective heat energy available in water vapor. And where does most of that latent heat energy come from? It comes, for the most part, in the form of warm waters evaporating into the air above the world’s oceans. More specifically to our current storm it comes in the form of record warm to near record warm temperatures in the waters of the Gulf Stream off the US East Coast (See Dr Jeff Master’s ‘The Future of Intense Winter Storms”).

image

(Sea surface temperatures off the US East Coast are more comparable to those seen during Summer than what would be typical for January. A 76 degree sea surface off Norfolk will provide a massive amount of heat and moisture to fuel the new kind of storm that is Jonas. Image source: Earth Nullschool.)

As Dr. Michael Mann noted in a tweet earlier this week, sea surface temperatures off the US East Coast are extraordinarily warm for this time of year. And Bill McKibben was absolutely astute in saying that these near record temperatures “should turbo-charge this weekend’s blizzard.”

And they’re absolutely ridiculously warm — in the range of 76 degrees Fahrenheit in a region about 150 miles due east of Norfolk, Virginia. A region of ocean over which the developing storm center will directly cross. An area of water that is now in the range of 7 degrees Celsius above average (13 degrees Fahrenheit). For the ocean surface, this is screaming hot — more typical to summer than anything one would expect to see in January, even in the Gulf Stream.

You just don’t see these kinds of temperature departures for the ocean — or at least you didn’t before human-caused climate change started to ramp up. But now we have them — an ocean surface hot enough to support a hurricane but one that will this weekend provide fuel for a blizzard. So the kind of blizzard we will have will not at all be like even the usual blizzards of the 20th Century. This is the new, worse variety that will sadly become more frequent. Destructive, heavy snowfall in the 4-5 inches per hour range, thundersnow and storm surges combined, swaths of hundreds of miles impacted and crippled. The kind for the new age of a human-heated atmosphere — destabilized to produce freak storms of a ferocity and frequency the likes of which we have never seen.

UPDATE — Snowfall Begins With Some Models Showing 4 Feet or More Possible (Average Guidance For Gaithersburg is 24-30 Inches)

Moderate snowfall began at 1:35 PM on Friday in my hometown of Gaithersburg, MD. Model guidance for our area is in the range of 24-30 inches, with as much as 4 feet coming up in some of the GFS ensembles.

Will be posting videos and related updates every 2-3 hours as conditions change.

UPDATE: 1-2 Inches on the Ground at Gaithersburg, MD as of 3:42 PM

(See Video of 3:42 PM snowfall here)

Wind and rates of snowfall have picked up somewhat over the past two hours. As of 3:42 PM, about 1-2 inches had fallen and the wind was visibly swaying some of the tree branches outside. Reports are coming in from regions to the south of a very heavy band of snow that should arrive in our area by later this evening.

Radar captures by the National Weather Service indicate this band setting up over much of Central and Eastern North Carolina — stretching northward through just west of Richmond. GFS model tracking and satellite confirmation indicate a coastal low developing in the region of Northern South Carolina. This low is beginning to transfer Atlantic moisture into the storm — pulling strong winds off that abnormally warm region of ocean just east of Norfolk and into the developing powerful snowfall band.

Jonas 420 PM NWS Radar

(Image source: National Weather Service.)

Sustained winds along the coast are now approaching gale force.  We should expect these winds to rapidly increase over the afternoon and evening hours even as the moisture feed and rate of snowfall intensifies.

UPDATE: Rate of Snowfall Still Picking up at 6:05 PM; Heavy Bands Expected by 10 PM

(See Video of 6:05 PM Snowfall Here)

Rates of snowfall continue to steadily increase for the Gaithersburg Area. As of 6:05 PM EST on Friday, 3-4 inches lay on the ground in Montgomery County Maryland. A heavy band of snow continued to gather to the south as the storm center went ongoing intensification near the border of South Carolina and North Carolina and just off-shore. Guidance provided by that National Weather Service indicates that heaviest rates of snowfall are still about 4 hours away. Radar indicates this band is forming just north of Richmond at this time.

UPDATE: At 10:30 PM, Heavy Snow Settles in with Six Inches Already on the Ground

(See 10:30 PM Video Here)

As of 1030 PM, heavy bands of snow had started to stream into the Gaithersburg area. Winds were picking up — in the range of 15-25 mph with some higher gusts. A healthy covering of about six inches of snowfall already lay on the ground. National weather service radar at this time indicated a series of stronger bands of precipitation just south of DC and moving northward. Meanwhile, atmospheric analysis indicates the center of Jonas now over Eastern North Carolina and strengthening. Over the next 6-12 hours Jonas is expected to intensify as it traverses toward the Chesapeake Bay. This should bring increasingly intense bands of snowfall over the area.

UPDATE: 1:35 AM Intense, Heavy Snow, 10-12 Inches on the Ground, Howling Gusts

By 1:35 AM, conditions again deteriorated for the region of Montgomery County. Snow accumulations had hit between 10 and 12 inches and the winds were really starting to howl and moan.

National Weather Service Radar indicated that the low pressure center had moved out over the Chesapeake Bay even as the wide-ranging storm really started to pull in substantial amounts of heat and moisture off the Atlantic. This kicked the storm into a higher intensity that will likely last, for the DC region, until around 1 PM tomorrow. We are entering the period of most intense storminess and snowfall now. Over the coming hours conditions could get quite extreme with 2-5 inch per hour snowfall rates and thundersnow in some areas. In other words — we’re starting to hit the height of this long-duration event.

Storm Really Starting to Crank Up Severe Snowfall over DC Area

National Weather Service Radar above shows very heavy snowfall bands moving directly over the DC Metro area at this time even as the Atlantic moisture feed grows more intense. Regional snowfall forecasts have remained quite extraordinary with most locations in the area now expecting between 18 and 40 inches. Still one heck of a night ahead!

Links:

NOAA (Please support public, non-special-interest based science, like the fantastic work done by the experts at NOAA)

Dr Jennifer Francis

Dr Michael E Mann

Bill McKibben

Anthony Sagliani

Dr. Jeff Masters: The Future of Intense Winter Storms

Jonas to Wallop 1,000 Mile Swath of US East Coast

Climate Reanalyzer

Convective Available Potential Energy (CAPE)

Earth Nullschool

Hat Tip to DT Lange

Hat tip to Colorado Bob

 

One Week After Frank, Arctic Sea Ice Hits New Record Lows

Extreme weather and climate change. The plight of human civilization facing loss of coastlines, stable climates, and predictable growing seasons. The plight of the polar bear. How are they all linked? Well, for one, it now appears that one of the most powerful storms to strike Iceland — an extraordinarily intense 928 mb low pressure system dubbed Frank by the UK Met Office — has played its hand in helping to drive Arctic sea ice to new daily record lows.

The storm, associated with a powerful high amplitude wave in the Jet Stream, aided in shoving some of the warmest temperatures ever recorded over the North Pole. Setting off a rare period of above freezing temperatures during polar night, this extreme weather event dumped an unprecedented amount of heat into the Arctic during what is typically its coldest season.

image

(Dr. Jeff Masters, chief meteorologist at Weather Underground, explains how extreme weather and weaknesses in the Jet Stream recently contributed to record warming and above freezing temperatures at the North Pole last week. Image source: Voice of America News Screenshot.)

It’s the kind of atmospheric heat engine whose climate and weather altering impacts I discussed with Dr. Jeff Masters, Dr Steven Amstrup, and the hosts of Voice of America’s news show #Hashtag — Michael Lipin and Andrew Palczewski — today. The kind of extreme events that become more and more common as the world warms up, dumping an inordinate amount of latent heat into storms as they form and intensify.

But this particular event’s far-ranging impact could also be seen in a warm temperature shift for the High Arctic during Winter. A shift that brought with it a flatlining of Arctic sea ice accumulation.

Typically, during December and on through mid-April, Arctic sea ice area and extent values continue to rise. The cold of polar night settles in over a broad area of water. Bereft of the heating rays of the sun and typically plunged into temperatures well below freezing, the ocean surface becomes covered in an expanding cap of ice. There it provides a stable environment for so many Arctic creatures that have made that place their home. But it has also helped to provide the stable climate of the Holocene — in which for more than 10,000 years human beings and our civilizations have been able to thrive.

chart

(Red flat line in the upper left shows that 2016 is starting off in the range of new record daily lows for Arctic sea ice. It’s one of the best barometers for climate change impact in the Northern Hemisphere and one that is still showing new declines, even in Winter. Image source: NSIDC.)

This year’s massive Arctic warm-up, in association with Frank, appears to have stranded that essential ice accumulation in dead stop. And as of January 4th, according to the National Snow and Ice Data Center, Arctic sea ice extent totals remained at 12.8 million square kilometers. That’s about 90,000 square kilometers below the previous record daily low set on the same day just five years ago during the Winter of 2011. It’s also an extent value fully 1 million square kilometers, an area the size of Texas and Montana combined, below the already depleted 1981 to 2010 average.

Cryosphere Today showed Arctic sea ice area also following that ominous flatline pattern — hitting 12.23 million square kilometers in coverage or the second lowest area on record for the day.

Extreme Arctic Warmth on January 5 2016

(Extreme Arctic warmth on January 5 of 2016 coincides with some extraordinary global heat in the above temperature anomaly map. It’s just one more day in a recent severe spate of Arctic warming that has helped to shove Arctic sea ice into new record low territory over recent days. Image source: Climate Reanalyzer.)

Continued warmer than normal temperatures in the Arctic in the range of 3 to 3.5 C above average for the region may well continue to drive this sea ice flat line over at least the next couple of days, pushing area measures into new record low readings even as extent continues to break records.

Failure to freeze during Winter is one of the driving factors of major Arctic sea ice declines during Summer (often called Winter power over at the Arctic Sea Ice Blog). So with sea ice hitting new lows for a, much warmer than normal cold season, we may need to watch out for potential new major losses come summer time. And that’s bad news for everyone — seals, walruses, polar bears, human beings and for many of the creatures below the Arctic Circle that rely on that frozen region for the maintenance of the climate they evolved and adapted to live in. Dr. Steven Amstrup, who has been a fearless advocate for the innocent creatures most likely to be impacted early by human-forced warming of the Arctic, I’m pretty sure, would agree.

Links:

Above Freezing Temperatures at North Pole During Winter

Voice of America News #El Nino, #North Pole, #Storm Frank

The National Snow and Ice Data Center

Cryosphere Today

The Arctic Sea Ice Blog

Polar Bears International

Weather Underground

Climate Reanalyzer

Scientific Hat Tip to Dr Steven Amstrup and Dr Jeff Masters

Hat Tip to Michael Lipin and Andrew Palczewski

Hat Tip to Kevin Jones for helping me keep my eye on the ball

 

Hawaii in a Sea of Storms: Abnormally Warm Pacific To Serve Up Unprecedented Double Cyclone Strike?

Hawaii in a Sea of Storms

(Iselle [center frame] and Julio [right frame] take aim on Hawaii [upper left] in most recent LANCE MODIS satellite shot.)

The Northern Pacific has been a very hot place this year. Above the Equator and stretching from Asia to the West Coast of North America, very few regions have witnessed below normal temperatures. And numerous very large hot zones continue to dominate off of Central and North America, between Alaska and Russia, and near Japan.

Overall, Pacific Ocean temperatures today are an excessive +0.93 degrees C above the, already hotter than normal, 1979 to 2000 average. And this extra heat, fueled by global warming, provides energy for the propagation of tropical cyclones well outside of their traditional ranges.

For Hawaii, this means falling under threat of two cyclone strikes within the period of as many days.

Hot Pacific Waters Projected to Spawn More Hawaiian Storms

Cyclone strikes in Hawaii are rare. The last time the island state was pummeled by a tropical storm was during the 1992 El Nino. But now it is threatened by not one, but two hurricanes. It is an event that is unprecedented in the entire satellite record. In other words, we’ve never seen this before.

Pacific SST Anomaly August 6

(Global sea surface temperature anomaly on August 6, 2014, shows an extreme +1.11 C positive temperature departure for the globe and a very strong +0.93 positive temperature departure for the North Pacific. Current science shows that warming ocean waters are extending the northward ranges of tropical cyclones, bringing regions like Hawaii under increasing threat. Image source: University of Maine.)

A shift in hurricanes toward Hawaii wasn’t entirely unexpected, however.

In 2013, Hiroyuki Murakami, from the International Pacific Research Center at the University of Hawaii at Mano together with a team of ocean and atmospheric researchers produced a report for Nature entitled Projected Increases in Cyclones Near Hawaii. The study modeled expected increases in Pacific Ocean surface temperature driven by human-caused climate change in the region near Hawaii. What it discovered was a marked increase in storm formation near Hawaii due to warming waters and related atmospheric changes.

The paper notes:

A key factor in projecting climate change is to derive robust signals of future changes in tropical cyclone activity across different model physical schemes and different future patterns in sea surface temperature. A suite of future warming experiments (2075–2099), using a state-of-the-art high-resolution global climate model1, 2, 3, robustly predicts an increase in tropical cyclone frequency of occurrence around the Hawaiian Islands.

Change in tropical cyclones

(Change in tropical cyclone frequency between now and 2075-2090 according to model projections produced in the Murakami Paper. Image source: Nature. See Also: Climate Change May Increase Number of Hawaiian Hurricanes)

What these researchers might not have expected was that a very warm Pacific during 2014 might well provide a prelude to what their models were predicting.

Iselle and Julio Barreling On In

For forecasts now show that Hawaii may well be in for a dose of double trouble — an extended period of stormy conditions starting early Friday and possibly not letting up until Monday as the unheard of storm pair barrels on in.

As of the most recent advisory, 85 mph hurricane Iselle was located about 650 miles to the east and southeast of Hilo. Iselle’s present and projected motion toward the west and northwest at around 15 miles per hour is expected to bring the storm, at a strong tropical storm intensity, over Hawaii’s Big Island by Friday. The storm is then projected to pass near the eastern islands before tracking back out into the open Pacific.

Coming directly behind Iselle, Julio is located about 1600 miles east-southeast of Hilo and packs maximum sustained winds of 75 miles per hour. The storm is also expected to weaken to strong to moderate tropical storm status before passing over or near the Hawaiian Island Chain along a track just to the north of Iselle’s path. This would bring the storm near the islands on Sunday, just two days after Iselle.

Threat Cones

(Threat cones for Iselle, Julio and Genevieve, all developing in an unusual region near the Central Pacific. Image source: NOAA.)

It’s worth mentioning that a third storm, Genevieve, has also developed in the mid-Pacific within about 1,000 miles of the Hawaiian chain — also in a rather rare region for tropical cyclone formation. Genevieve, however, is not expected to threaten the islands as it tracks westward, taking a long journey toward Asia.

Conditions in Context

These three cyclones generated over warm waters near the central equatorial Pacific. The storms emerged from a convective pattern in a region that typically only shows robust storm development during El Nino.

Though El Nino is not officially ongoing, atmospheric conditions over the past few weeks have become more favorable even as a new warm Kelvin Wave appears to be forming in the waters of the Western Pacific. NOAA still forecasts a weak to moderate El Nino for 2014, but conditions, though somewhat more favorable, remain murky.

Sea surface temperatures in the region of Hawaii

(Current sea surface temperatures in the region of Hawaii are a in rather warm and mostly above average range from 26 to 28 C [80 to 83 F], more than enough to sustain powerful tropical cyclones. Generally, water temperatures above 75 F are needed for tropical cyclone formation and strengthening. The primary limiters to both Eselle’s and Julio’s strength remains wind shear, which is expected to reduce both storms to tropical storm status over the coming days. Even so, Hawaii is in for an ongoing period of unprecedented weather. Image source: National Hurricane Center.)

It’s worth noting that a rash of storms in this region is unprecedented in the satellite era and is especially odd considering that ENSO remains neutral. It is very likely that the outbreak is in some way related to the larger Pacific Ocean warming trend associated with human-caused climate change acting together with an El Nino-like development trend.

UPDATE: Due to warm surface waters in the region of Hawaii and somewhat more favorable than expected atmospheric conditions, Iselle is expected to make landfall on the big island of Hawai’i near Hawaii City later today. Expected maximum sustained winds at the time of landfall are near 75 miles per hour.

Hurricane tracking from NOAA brings the storm directly over the Big Island at around midnight after which the storm is predicted to skirt Maui and Oahu:

NOAA Hurricane Track Iselle

(NOAA’s most recent projected storm track for Iselle. Image source: National Hurricane Center.)

Links:

Double Trouble: Hawaii Braces For Hurricanes Iselle and Julio

Climate Change May Increase Number of Hawaii Hurricanes

Projected Increases in Cyclones Near Hawai

NOAA

University of Maine

LANCE MODIS

National Hurricane Center

Hat tip to Eleggua

 

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