More and more extreme weather

More and more extreme weather

The weather is getting more and more extreme. On April 23, 2016, temperatures in India were as high as 47.7°C or 117.9°F. At the same time, temperatures in California were as low as -12.6°C or 9.2°F, while temperatures in Greenland were as high as 3.6°C or 38.6°F. Meanwhile, Antarctica was as cold as -60°C or -76°F.


The situation in India is most worrying. Temperatures are very high in many locations. India has been experiencing heatwave conditions for some time now, as reported in this and in this earlier posts.


[ click on images to enlarge ]
More extreme weather goes hand in hand with changes that are taking place to the jet stream, as also discussed in earlier posts (see further below).

As the Arctic warms up more rapidly than the rest of the world, the temperature difference between the Equator and the North Pole decreases, which in turn weakens the speed at which the north polar jet stream circumnavigates the globe. This is illustrated by the wavy patterns of the north polar jet stream in the image on the right.

The outlook for the next week shows the north polar jet stream move higher over the arctic, and to eventually disintegrate altogether, while merging with the subtropical jet stream over the Pacific Ocean.

The video below shows how a very wavy jet stream is projected to disintegrate over the Arctic Ocean over the coming week.


This makes it easier for warm air to move into the Arctic and for cold air to move out of the Arctic, in turn further decreasing the temperature difference between the Equator and the North Pole, in a self-reinforcing feedback loop: "It's like leaving the freezer door open."

Temperature forecasts for the Arctic Ocean are high, with anomalies projected to be above 4°C for the Arctic over the coming week.

The image on the right shows one such forecast, projecting a temperature anomaly of 5.31°C or 9.56°F for the Arctic on April 27, 2016, 1500 UTC, while an earlier forecast projected a 5.34°C or 9.61°F anomaly (hat tip to Mark Williams).

The danger is that the combined impact of high air temperatures and ocean heat will cause rapid demise of Arctic sea ice over the next few months.


On April 22, 2016, the sea surface was as much as 11.3°C or 20.3°F warmer than 1981-2011 (at the location off the coast of North America marked by the green circle).

High ocean heat is further accelerating Arctic sea ice demise, as the Gulf Stream keeps carrying ever warmer water into the Arctic Ocean. The image below, created with an image from the JAXA site, shows that Arctic sea ice extent was well under 13 million km2 on April 19, 2016, and about 1 million km2  less than the extent in the year 2012 around this time of year.


Demise of the sea ice will cause even more rapid warming of the Arctic Ocean, with the danger that more heat will penetrate sediments that contain huge amounts of methane in the form of hydrates and free gas, threatening to trigger huge methane releases and cause runaway warming.

Methane levels are increasing strongly. This may not be as noticeable when taking samples from ground stations, but the rise is dramatic at higher altitudes, as also discussed earlier in this post and in this post.

Methane levels in ppb (parts per billion, at bottom of image)
The conversion table below shows the altitude equivalents in feet, m and mb.

57016 feet44690 feet36850 feet30570 feet25544 feet19820 feet14385 feet 8368 feet1916 feet
17378 m13621 m11232 m 9318 m 7786 m 6041 m 4384 m 2551 m 584 m
 74 mb 147 mb 218 mb 293 mb 367 mb 469 mb 586 mb 742 mb 945 mb

The situation is dire and calls for comprehensive and effective action, as described at the Climate Plan.


Related

- What's wrong with the weather?
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