Friday, March 09, 2012
Expanding the Frame
Here is the official anomaly chart for Northern Ocean sea ice over the last 32 years. Starting in 1979 when ice extent noticing satellites were launched, it shows a downward trend which fits the Global Warming alarmists' prediction that the effects of man-made CO2 in the atmosphere will be amplified at the poles (The sea ice in the Southern Ocean has gone up but at a much slower rate).
Not only is it going noticeably down, but it seems to be doing so at a quickening rate although since 2007 it's somewhat rallied.
Here, however, is an older chart that includes the National Oceanic and Atmospheric Administration's best efforts both before and after the satellites were launched. The pre-satellite data was from Navy overflights of the Arctic. Or so says the 1990 IPCC Report on Climate (pp. 224-5), which report is where this older graph comes from. Totally different picture here. The IPCC warned us that current and wind make it difficult to attribute melting of sea ice to warmer temperatures alone. Good call.
So it hasn't only gone down at an alarming rate. With the wider frame of reference, the pattern revealed is the often-seen-in-nature sine curve of a decades long cycle of differential melting and freezing. Well perhaps not a perfect sine curve, as the alarming freezing was over a 4 year period and the 'alarming' melting was over 3 decades. Still, it's almost always better to have more information rather than less.
(h/t Steven Goddard)
Labels: Global Warming Alarmism; Bigger Picture of Northern Sea Ice