Seeing the environmental forest

I published a prediction of Arctic sea ice extent on July 1 that was based on September sea ice extent from 1979 to 2013.  That model yielded a prediction that the average extent for September 2014 would be 4.135 million square kilometers.  However, that model does not take into consideration any other information we have on Arctic sea ice, such as the ice extent in previous months of the year.  It just gives the general trend of sea ice in September from year to year.  You cannot use it to predict ice extent based on current ice extent or conditions.

NewsMax.com printed a poorly writen story about Antarctic sea ice intended to sow confusion amongst its readers which was unfortunately shared on my Facebook timeline by an acquaintance.  However, the article is even worse than being merely poorly written.  The "author," Sandy Fitzgerald, extensively plagiarizes a blog post by Harold Ambler while leaving out nearly everything Ambler wrote about why Antarctic sea ice is increasing.  Fitzgerald manages to make it sound like a new record extent in Antarctic sea ice somehow contradicts global warming.  Ambler's original is a far more nuanced argument.

One seemingly persistent myth about the Arctic is that there is no correlation between Arctic air temperature and sea ice extent.  At first glance, that myth appears to be true, as Arctic temperatures have noticeably risen whereas sea ice extent shows little overall change. The correlation appears even worse when plotting sea ice extent versus temperature directly. Taking a closer look, however, reveals the reason for the apparently poor correlation: The large seasonal cycle in sea ice extent data.  The cycle obscures the overall trend in sea ice data—and the correlation of that trend with the trend in Arctic tropospheric temperature.  Once that cycle is removed via a 12-month moving average, the trend in sea ice extent and the negative correlation between extent and temperature is clearly revealed. The direct comparison shows that the decline in Arctic sea ice extent has accelerated as Arctic tropospheric temperature increased. Extent = 11.6846713 + -0.9...

One of the current rumors circulating in climate change denier circles is that the Arctic sea ice is recovering, with a record ice gain, and that Arctic ice in August 2013 60% higher than in August 2012 and is the highest in "years."  Let's examine those claims. First, here's a graph showing the 12-month moving average of Arctic sea ice from January 1979 to August 2013: Not much to say there.  So far, the 12-month moving average shows no sign of any recovery.  Arctic sea ice extent remains far below the 1979 start point or even where it was before 2005.  However, the claim is that the ice gain since September 2012 set a record.  Normally, Arctic ice extent reaches the yearly minimum in September at the end of summer, with a maximum the following March at the end of winter.  The ice gain is the difference between those months. March extent has been declining linearly by an average of -36,581 km 2 per year whereas the decline in September has be...

I've run across several skeptic claims recently that Arctic sea ice extent is within the normal range for this time of year, as well as claims that Antarctic sea ice is growing  While both are true, the implication that we shouldn't be concerned with the Arctic sea ice melting because of those facts is pure nonsense.