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Australia’s Hot Ocean Blob Fuels Record Heat, Extreme Weather, Risk to Coral Reefs

Between Australia and New Zealand there’s a kind of climate change fed thing on the prowl in the off-shore waters. It takes the form of an angry layer of far warmer than normal surface water. And it’s been lurking around since late November.

(A hot, angry blob of much warmer than normal ocean temperatures has erupted between Australia and New Zealand.)

We can see this disruptive beast pretty clearly in the sea surface temperature anomaly maps provided by Earth Nullschool. Today’s readings show temperatures in this new blob hitting between 3.5 and 4.2 degrees Celsius above average across a broad expanse of ocean.

That’s much, much warmer than normal for this region of water. A place where 2 degree above average sea surface readings would tend to be unusual. But with global temperatures now hitting between 1.1 and 1.2 C above 1880s averages, we’re starting to see the climate dice more loaded for these kinds of extreme events. To be clear, this is not the kind of extremity we’d experience in a world at 2 C warming, or 4 C warming, or 7 C warming. But we’ve moved up the scale and weather, temperature, and ocean environmental conditions are being harmfully impacted.

(The above graph shows how temperatures have shifted outside of 20th Century ranges. During 2014-2017, the world dramatically warmed — generating further rightward movement in the bell curve. Temperature has an impact on everything from drought, to the severity of thunderstorms, to the length and intensity of fire season, to the fuel available for the most powerful hurricanes, to algae blooms, to coral bleaching events. Image source: NASA GISS.)

Back on November 30th, the blob contributed to an extreme rainfall event impacting Southeast Australia. One that dumped upwards of 10 inches or more in a rather short period. Since that time, South Australia has been seeing continued instances of extreme weather. Over recent days, towering supercell storms rocked Victoria with lightning, flash floods, damaging winds, and golf-ball sized hail. In Melbourne, a flood washed away a 40 foot section of a foot path. Meanwhile western parts of Sydney Australia were sweltering under record-shattering heat — with temperatures hitting a never before seen high of 111 F (44 C) on Tuesday, December 19th. Other regions experienced over 113 F (45 C) temperatures.

(Hot ocean blob feeds record breaking heat across Australia on Tuesday. Image source: WindyTV.)

The off shore hot blob is laying its hot, moist tendrils of influence on these weather extremes in a number of ways. First the blob is belching an enormous amount of moisture into the atmosphere above the local ocean. This moisture is being cycled over SE Australia by the prevailing winds and is adding convective energy to thunderstorms. In addition, the blob is also contributing to a sprawling ridge of high pressure that sits squarely over top it. The ridge, in turn, is baking parts of Australia with record hot temperatures.

Hot ocean blobs like the thing off Australia are a feature of human-caused climate change in that ocean and atmospheric warming generates an environment in which these pools of excessive warmth are more likely to form. These are anomalous events that stretch or break the boundaries of past weather and climate patterns by adding unusual amounts of heat and moisture to local and region climate systems in the environments in which they form. A hot blob forming off the U.S. West Coast during 2014-2015 contributed to a number of climate change associated events like the severe California Drought, a ridiculously resilient ridge of high pressure, western wildfires, intense rains into Alaska and Canada and a number of mortality events among sea life that were triggered by heat, low oxygen content, or blooms of harmful microbes that thrive in warmer ocean environments.

Though short-lived in comparison to the Hot Blob that lurked off the U.S. West Coast for the better part of two years, the Australia-New Zealand blob is already having a variety of atmospheric and oceanic impacts. Notably, in addition to the wrenching influences on local and regional weather described above, the blob is also contributing to risks to Australia’s corals.

(NOAA’s Coral Reef Watch shows strong risk of coral stress continuing through March of 2018. The hot blob of ocean water off Australia is contributing to a situation where reefs like the GBR are again at risk. Image source: NOAA.)

Over the past two years, the Great Barrier Reef (GBR) experienced back to back bleaching events. These were the worst ever seen by the reef. And they were triggered by human-caused climate change. This year, in part due to the blob, risks to corals between Australia and New Zealand are again high. If the blob shifts north and west, then the GBR again falls under the gun. This time for a third year in a row. Notably coral reef stress warnings and alerts abound throughout the zone between Australia and New Zealand in NOAA’s Coral Reef Watch report at present.

Due to the potential to continue to contribute to various weather and ocean impacts, the present climate change influenced hot blob between Australia and New Zealand bears continued monitoring. It has, however, already generated a number of impacts. And it is likely that more will follow.

CREDITS:

Hat tip to Carolyn Copeland

Hat tip to Guy Walton

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Monsoon Disrupted By El Nino + Climate Change as India Suffers Deaths, Crop Losses from Extreme Heat.

May is the month when the massive rainstorm that is the Asian Monsoon begins to gather and advance. This year, as in many other years, the monsoon gradually formed along the coast of Myanmar early in the month. It sprang forward with gusto reaching the Bay of Bengal by last week.

And there it has stalled ever since.

On May 25-27, an outburst of moisture from this stalled monsoonal flow splashed over the coasts of India. But by the 29th and 30th, these coastal storms and even the ones gathering over the Bengali waters had all been snuffed out. The most prominent feature in the MODIS shot of India today isn’t the rainfall that should be now arriving along the southeast coast, but the thick and steely-gray pallor of coal-ash smog trapped under a persistent and oppressive dome of intense heat.

Monsoon Disrupted

(MODIS shot of India on May 30th. See the open stretch of blue water in the lower right frame? That’s the Bay of Bengal which borders coastal India. During a normal year at this time, that entire ocean zone should be filled with the storm clouds of a building monsoon that is already encroaching on coastal India. Today, there is nothing but a smattering of small and dispersed cloud through a mostly clear sky. Image source: LANCE-MODIS.)

Monsoon Described as Feeble

Official forecasts had already announced as of May 27th that the annual monsoon was likely to be delayed by at least a week for southeast regions of India. Meanwhile, expected monsoonal rainfall for western and northern sections of India for 2014 fell increasingly into doubt.

From The Times of India:

The monsoon is likely to be delayed by 10 days, according to scientists at the Indian Institute of Tropical Meteorology (IITM) here. The IITM’s third experimental real-time forecast says that a feeble monsoon will reach central India after June 20 as against the usual June 15. Last year, the monsoon had covered the entire country by June 15.

The annual monsoon is key to India’s agriculture. The substantial rains nurture crops even as they tamp down a powerful heating that typically builds throughout the sub-continent into early summer. Without these rains, both heat and drought tend to run rampant, bringing down crop yields and resulting in severe human losses due to excessive heat.

But, this year, heat and drought are already at extreme levels.

Major Heatwave Already Results in Loss of Life for 2014

As early as late March, the heatwave began to build over the Indian subcontinent. The heat surged throughout the state, setting off fires, resulting in a growing list of heat casualties, shutting down the power grid and spurring unrest. Meanwhile, impacts to India’s agriculture were already growing as the Lychee fruit crop was reported to have suffered a 40% loss.

By late May, temperatures across a broad region had surged above 105 degrees shattering records as the oppressive and deadly heat continued to tighten its grip.

In a country surrounded on three sides by oceans, it is a combination of heat, humidity and persistently high night-time temperatures that can be a killer. Wet bulb temperatures surge into a high-risk range for human mortality during the day even as night-time provides little respite for already stressed human bodies. Such extreme and long-duration heat doesn’t come without a sad toll. As of today, early reports indicated a loss of more than 56 lives due to heat stroke (In 2012 and 2013, total Indian heat deaths were near 1,000 each year). That said, final figures on heat losses are still pending awaiting complete reports from all of India’s provinces.

“Climatologically, we know that heatwaves are increasing in frequency and the number of days exceeding 45ºC temperatures is increasing. The frequency will increase further with global warming, hence this is a good example of a situation where science and disaster management can come together and avert damage,” a spokesman for India’s National Disaster Management Authority noted on Friday.

Hot Dust

(Hot Dust. A dust storm rolls through New Delhi on Friday amidst furnace-like 113 degree heat snarling traffic and resulting in the tragic loss of 9 more lives. Image source: Gaurav Karoliwal/YouTube Screenshot.)

Today the heatwave continued to gain ground, with Kota and Rajasthan reaching an all-time record of 116 degree F (46.5 C) as New Delhi’s mercury hit 113 degrees F in the midst of a drought-induced dust storm. Dust shrouding the city spurred traffic chaos and in the heat, darkness, and confusion nine more souls were lost.

After two months of growing disruption due to heat and drought, the lands and peoples of India cry out for a Monsoon that is running later and later with each new weather report.

Climate Change + El Nino: Adding Heat and Beating Back the Monsoon

As systems approach tipping points, they are more likely to tilt toward the extremes.

For India this year, its seasonally warmest period from April to May found severe heat amplification from a number of global factors. First, climate change seeded the ground for the current Indian heatwave by adding general heat and evaporation to already hot conditions. With global average heating of +0.8 C above 1880s levels amplifying in the hot zones, early moisture loss due to higher-than-normal temperatures produces a kind of snowball effect for still more warming. Essentially, the cooling effect of water evaporation is baked out early allowing for heat to hit harder just as typical seasonal maximums are reached.

Equatorial Pacific Ocean Temperatures May 30

(Equatorial Pacific Ocean temperatures warmed to +0.63 C positive anomaly on May 30th, extending further into El Nino Range. Image source: University of Maine.)

In addition, this year saw rapid progress toward an El Nino event in the Pacific Ocean with sea surface temperatures warming into the El Nino range by mid-May and continuing to ramp higher. By today, Equatorial Pacific anomalies had hit +0.63 C according to GFS analysis, extending a run into El Nino conditions.

El Nino events typically allow for the formation of hot, drier air over India. These air masses tend to engender extreme heatwaves like the one we are seeing now even as they delay the onset of cooling monsoonal rains. In essence, the monsoon is confronted with a heavy and entrenched wall of hot air that doggedly resists being shoved aside. And this is the very situation we observe now over India — a sputtering monsoon to the east getting bullied by a brutally hot and thick air mass that just won’t give ground. Climate change only exaggerates the problem by increasing the intensity and inertia of the hot air mass.

Major monsoonal disruptions typically occur during years following an El Nino’s peak heating impact. For example, in 1998, during a period following an extreme El Nino, India suffered one of its most severe droughts and monsoonal delays on record. But during recent years preceding El Nino, such as 2009, India also saw severe heat, drying, and crop damage due to a weakening of the annual summer rains. So an early monsoonal enfeeblement and coincident strong heatwaves and droughts over India with El Nino still forming is cause for some concern and bears further monitoring.

Currently, temperatures over India are surging to between 5 and 12 degrees Celsius above already hot averages. With heat and drought firmly in place, forecasts are calling for a 1 to 2 week delay in the cooling and moisture-bringing monsoon as India continues to swelter.

Links:

Heatwave Persists Across India

LANCE-MODIS

Northern India to Endure Scorching Heat and Drought due to Weak Monsoon

Heatwave Continues in Raj, Kota

Lychee Crop Suffers 40% Loss Due to Heatwave

Dust Storm Blamed for 9 Deaths, Transportation Nightmare

Indian Monsoon Delayed as Heatwave Continues

Ten Day Delay in Monsoon

El Nino Delays Rain, May Spell Trouble for Government

El Nino May Disrupt Monsoon

(Hat Tip to Colorado Bob RE Tipping Points)

(Hat Tip to Mark from New England for Excellent Clarifying Questions)

 

 

3.8 Million Square Kilometers Sea Ice Extent and Falling: Highlights of Strange and Disturbing Arctic Melt Season

Earlier this year, a group of forecasters attempted to model sea ice melt for the upcoming summer. The result was a range of forecasts predicting anywhere from 4.1 to 4.9 million square kilometers of sea ice left by the end of this melt season. These predictions were based on observed weather patterns that, in the past, had not been conducive for rapid melt.

Instead, this summer has seen the lowest levels ever for sea ice in the satellite record and likely, according to recent scientific observations, the lowest levels in 3,000 years. Today’s sea ice extent total, according to JAXA, has touched the 3.8 million square kilometer mark, 300,000 square kilometers below the lowest level predicted and more than 430,000 square kilometers below the previous record low set in 2007. It is just the latest goal post reached in a year of extreme and record melt.

So why has this happened? Observations of weather events have shown that conditions were not those typically favorable for a large melt. What changed to make such a rapid and historic melt come to pass? Is it possible the Arctic sea ice has passed a tipping point?

One hint for a potential answer to this question is an analysis of sea ice volume. Since the last record low for sea ice extent set in 2007, sea ice volume measurements have come in consistently lower each year. This year after year decline in total sea ice mass results in much thinner ice. So though the coverage may not have contracted as much, the ice underneath was growing thinner and thinner.

Hold that notion of thin ice in your mind. Now, let’s move on to the issue of weather. Usually, large areas of sea ice aren’t vulnerable to storms. In the past, storms during summer time haven’t contained enough energy to break the thicker ice. But since the ice began melting early in the 20th century, something strange has cropped up. Beginning in the later 20th century, more powerful storms began to form in the Arctic during summertime. These Arctic cyclones packed much more energy than their milder forebears and, over time, the strength of these storms continued to increase.

Now let’s fast forward to this summer. An area of thin, mostly broken sea ice was slowly melting in the Arctic. Then, a powerful storm formed off East Siberia and quickly tore through this ice — scattering it, casting it hither and yon, submerging it in a warming Arctic Ocean. By the time the storm was finished, a huge area of ice had melted.

After the storm, rapid declines continued almost unabated.

So one wonders, has the Arctic sea ice reached a tipping point? Are the number of environmental stresses that can cause rapid melt multiplying? Is the thinning ice just no longer able to absorb any insult of weather, wind, or heat? Or has the warming Arctic Ocean just gotten too hot for summer sea ice overall?

Given the serious anomaly of the 2012 melt season, it would seem a very strong possibility that we have entered a new, dynamic phase of melt. A phase in which past assumptions are rendered moot and the accumulating melt feedbacks are increasingly overwhelming the Arctic climate.

Links:

http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

http://www.arcus.org/search/seaiceoutlook/2012/june

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