Tuesday, August 23, 2016

Stay Frosty Antarctica

Stay Frosty Antarctica | The Resilient Earth:
"Every few years there appears a spate of articles and even TV reports that the ice of Antarctica is about to disintegrate and drown us all.
This is reported in serious tones by well coiffed media airheads who have not a clue what they are talking about. 
But this is OK, many scientists don't either.
You see, there is nothing settled about climate science, especially about what is going on at the bottom of the world.
A News & Views article in Nature by Eric J. Steig, from the Department of Earth and Space Sciences, University of Washington, sets the stage for one new report:
The Antarctic Peninsula is a triangular, mountainous land with a coastline of dramatic, calving glaciers and rich wildlife, and it exemplifies the popular image of Antarctica. Over the past half century, it has been one of the most rapidly warming places on Earth. This warming is associated with major physical and biological changes, including a decline in the Adélie penguin population1 and the disintegration in 2002 of a large portion of the Larsen B ice shelf, a major geographical feature that had existed for millennia. It is natural to view the changes at this northernmost point in Antarctica as part of the inexorable southward march of anthropogenic climate change. It may thus seem remarkable that Turner and colleagues now report that the Antarctic Peninsula has actually cooled in the past two decades.
What?
The melting Antarctic, the coldest place on Earth, is actually getting colder? 
That is precisely what John Turner and colleagues have reported in “Absence of 21st century warming on Antarctic Peninsula consistent with natural variability.”
Here is part of the paper's abstract, explaining just what was studied.
Here we use a stacked temperature record to show an absence of regional warming since the late 1990s. The annual mean temperature has decreased at a statistically significant rate, with the most rapid cooling during the Austral summer. Temperatures have decreased as a consequence of a greater frequency of cold, east-to-southeasterly winds, resulting from more cyclonic conditions in the northern Weddell Sea associated with a strengthening mid-latitude jet. These circulation changes have also increased the advection of sea ice towards the east coast of the peninsula, amplifying their effects. Our findings cover only 1% of the Antarctic continent and emphasize that decadal temperature changes in this region are not primarily associated with the drivers of global temperature change but, rather, reflect the extreme natural internal variability of the regional atmospheric circulation..."

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