Seeing the environmental forest

David Rose, who is no stranger to cherry-picking climate data and then weaving artful tales based on those cherry-picks, is back with yet another example of his perversity .  This time, he's trumpeting a 2-year increase in Arctic sea ice as measured on a single day: August 25, 2012 vs. August 25, 2014, claiming a 43% increase based on those two very specific days.  This is misleading for multiple reasons, one of which he himself admits in small type under that large flashy graphic at the top of his article: " These reveal that – while the long-term trend still shows a decline – last Monday, August 25, the area of the Arctic Ocean with at least 15 per cent ice cover was 5.62 million square kilometres." (emphasis added). So, just what does that long-term trend show? This:

I've previously written about the recent changes in polar sea ice .  This post compares the current trends in Arctic ice with the previous century.  I've recently read several claims that the recent melting is matched by melting episodes in the 1920s and 1940s.  However, those claims are pure bunk.  Walsh and Chapman ( 2001 ) compiled records on Arctic sea ice extent since 1870 (updated data available here ).  I've graphed their July-September average, together with the July-September average measured by satellites since 1979: