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Showing posts from August, 2015

Arctic Sea Ice Collapse Threatens - Update 6

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The image below shows Arctic sea ice extent, with the blue dot indicating that extent for August 22, 2015, was 5.382 million square kilometers. The record shows that, at this time of the year, extent was only lower in 2007, 2011 and 2012. There are a number of reasons why sea ice could fall dramatically over the next few weeks. First of all, the situation today is in an even worse condition than one might conclude when looking at sea ice extent alone. The way NSIDC calculates extent is by first dividing the satellite image into a grid and then including each cell in extent that has 15% or more ice. So, if a few small and very thin pieces of ice floating in a cell happen to cover 15% of a cell, it is counted in as "sea ice". There is quite a difference between the sea ice that was 5 meters thick north of Greenland in 2012 and the ice that is present there now. The image on the right shows the north-east corner of Greenland on the bottom left. There is almost no ice north of th

Ocean Heat Invades Arctic Ocean

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[ click on image to enlarge ] NOAA analysis shows that, on land, it now is about 1°C (1.8°F) warmer than the 20th century average. July 2015 was the warmest month ever recorded for the globe. The combined average temperature over global land and ocean surfaces for July was the all-time highest monthly temperature in the 1880-2015 record – it was 16.61°C (61.86°F), i.e. 0.81°C (1.46°F) above the 20th century average.  Sea surfaces were very warm as well, in particular the North Pacific, which on August 22, 2015, was exactly 1°C (1.8°F) warmer than it was compared to the period from 1971 to 2000 (see Climate Reanalyzer image right). The July globally-averaged sea surface temperature was the highest temperature for any month in the 1880-2015 record. In July 2015, the sea surface on the Northern Hemisphere was 0.87°C (1.57°F) warmer than it was in the 20th century, as illustrated by the NOAA graph below.  As the image below shows, the July data for sea surface temperature anomalies on t

Disappearance Of Thick Arctic Sea Ice

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[ view full image at facebook  ] Arctic sea ice is in a horrible state. On August 16, 2015, Arctic sea ice extent was 5.786 million square km, the smallest extent on record for this time of year except for the years 2007, 2011 and 2012, as illustrated by the image on the right. The situation today is even worse than one might conclude when looking at sea ice extent alone. Thick sea ice is virtually absent compared to the situation in the year 2012 around this time of year, as illustrated by the image below comparing sea ice thickness on August 16, 2012 (left) with August 16, 2015 (right). The ice used to be over 4 m thick, or over 13 ft thick, north of Greenland and the Canadian Archipelago. This thick multi-year ice has been a feature of the Arctic sea ice for over 100,000 years. It used to be there all year long, unlike the thinner ice that could melt away entirely during the melting season. The disappearance of this thick multi-year ice is a major development. Why? Until now, the th

Arctic Sea Ice Collapse Threatens - Update 5

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The image below shows sea surface temperatures in the Arctic as at August 15, 2015. Below a time lapse video, covering the period from May 30 to August 15, 2015, created by Cameron Forge with daily images from NPEO Webcam 1 from the North Pole Environmental Observatory, National Science Foundation . For a drift map of the buoys, also see this page . Below is an August 14, 2015, satellite image from Arctic.io showing that there is very little sea ice to the north east of Greenland and what is there looks to be very thin as well. The image below shows Arctic sea ice extent, with the blue dot indicating the extent for August 14, 2015. More will follow soon. Sea surface temperatures in the Arctic as at August 15, 2015.http://arctic-news.blogspot.com/2015/08/arctic-sea-ice-collapse-threatens-update-5.html Posted by Sam Carana on  Sunday, August 16, 2015

Arctic Sea Ice Collapse Threatens - Update 4

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On August 12, 2015, Arctic sea ice extent was 6.043 million square km. For this date, the only years on record that sea ice extent was smaller were 2007, 2011 and 2012, as illustrated by above image. Similarly, on August 11, 2015, Arctic sea ice area on August 11, 2015, was 3.67025 million square km (bottom end yellow line). For this date, the only years on record that sea ice area was smaller were 2007, 2011 and 2012. So, will Arctic sea ice reach a record low this year? The situation is actually a lot worse than it appears when just looking at sea ice extent and area up until now.  In fact, sea ice is in a horrible state. One indication of this is the almost complete absence of thick sea ice on August 12, 2015, which becomes even more clear when compared with the situation in 2012 for the same date, as illustrated by the image below.  The absence of thick sea ice means that, in terms of volume, there is very little sea ice left to melt until the minimum volume will be reached around

The Methane Monster

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At no time in the past did humans exist under conditions that we are facing now, no matter how far back you go in history. Global mean methane levels as high as 1840 parts per billion were recorded on August 4, 2015. This is the highest mean level since records began and this new record is likely to be superseded by even higher levels soon. The carbon dioxide that is released now will only reach its peak impact a decade from now. Methane's high immediate impact makes it more important than carbon dioxide emissions in driving the rate of global warming over the coming decade. The Pacific Ocean is very warm at the moment. Warm water flows from the Pacific Ocean through the Bering Strait into the Arctic Ocean. Sea surface temperatures in the Bering Strait were as high as 20.5°C (or 69.1°F) on August 4, 2015. That is 8.7°C (or 15.6°F) warmer than the water used to be. Sea surface temperatures as high as 11.8°C (53.2°F) were recorded in between Greenland and Svalbard on August 7, 2015,

Record High Methane Levels

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[ click on images to enlarge ] As the top image shows, sea surface temperature anomalies in the Bering Strait on August 4, 2015, were as high as 8.7°C (15.6°F). Such high anomalies are caused by a combination of ocean heat, of heatwaves over Alaska and Siberia extending over the Bering Strait, and of warm river water run-off. As the image on the right shows, sea surface temperatures in the Bering Strait were as high as 20.5°C (69.1°F) on August 4, 2015. As warm water flows through the Bering Strait into the Arctic Ocean, it dives under the sea ice and becomes harder to detect by satellites that typically measure water temperatures at the surface, rather than below the surface. The image below shows sea surface temperature anomalies from 1971 to 2000, for August 6, 2015, as visualized by Climate Reanalyzer. Climate Reanalyzer applies a mask over sea-ice-covered gridcells, reducing anomalies in such cells to zero. Below is a NOAA image, for August 5, 2015, also with anomalies from 1971