Sea Ice Copenhagen Update
Posted by Jeff Id on December 9, 2009
A special post for those who would save us from the global warming. The regulars already know we do these sea ice plots from the NSIDC gridded satellite data.
Sea ice – extent full satellite record, barely significant trend WRT high frequency weather noise.
Global sea ice area is even closer.
This one is interesting because it shows that without 1978 the past 30 years have not shown a statistically significant decline in sea ice. What makes it even better is that in 1978 there are only 2 months of data starting from October 26. So the above graph which shows a less than 95% confidence that the decline is not ‘weather’ noise is only missing the first 2 months.
So of course we should plot the stats for all the years, just to make sure I’m not cherry picking.
Global Sea ice trend by year only (barely) crosses 95% significance when the first two months of satellite data is included for the entire record.
Just for fun, from the uber-Scientific and obviously a-political Copenhagen Diagnosis report we learn that ‘scientists’ can only see Arctic Sea ice.
Rapid Arctic sea-ice decline: Summer-time melting of Arctic sea-ice has accelerated far beyond the expectations of climate
models. The area of summertime sea-ice melt during 2007-2009 was about 40% less than the average prediction from IPCC
AR4 climate models.
Below is the Arctic Sea ice anomaly.
So the question is, is sea ice declining – the easy answer is clearly yes. However, the more nuanced answer is yes but it appears globally to be an insignificant amount of melt which could be due to short term variations caused by high frequency weather patterns. What’s more is that we only have 30 years of data here to work from and there is substantial evidence that this ice has melted in the past and the whole trend could quite easily be part of a much longer trend as shown in an awesome post on arctic history by Tony Brown.
I do a special plot of Global ice anomaly at tAV where I add back in the average ice area on the earth. It’s important for people to visualize because it gives a slightly different impression than the ‘scientists’ desperately want you to see. As I say often here, don’t take my word for it, make your own mind up. — I say it for lurkers though, most blog commenter’s have little trouble with expressing opinion right?
Just to make the effects of variation of weather on Sea Ice and Polar bears (which there are more of today) below is a new and much improved video on global Sea Ice. The resolution is better, both poles are shown at the same time and I’ve brought it up to date for this year.
As my 3 YO said , smaller, smaller ,smaller, bigger, bigger, bigger, smaller ,smaller smaller, bigger big…..
The R code for this is a bit sloppy, but you’re welcome to it – email me on the right.