Analysis: ‘The Truth Behind Record Sea Temperature Claims’
The Truth Behind Record Sea Temperature Claims
By Paul Homewood h/t John Kelly http://www.theage.com.au/environment/climate-change/record-seasurface-temperatures-in-pacific-point-to-record-warmth-in-2015-and-2016-20150414-1mjooh.html The Age are banging their global warming drum again, this time over what they describe as record sea temperatures around Australia. And, of, course, its YOUR FAULT! As usual, however, when you delve into the facts, things aren’t quite as straightforward as they pretend. The Australian Bureau of Meteorology, BOM, offer a full set of data/graphs for sea temperatures in that part of the world, right back to 1900. Now let me first of all say that I have grave doubts about the accuracy and comparability of sea temperatures from so far back, and even into more recent decades. Methods of measurement have changed over the years, and huge question marks should be put against the coverage. Nevertheless, this is the only data we have got, and it is from this that “record” claims are being made. So, given that proviso, what does the data tell us? http://www.bom.gov.au/cgi-bin/climate/change/timeseries.cgi?graph=sst&area=aus&season=0112&ave_yr=10 1) The first thing to notice is that the long term trend has been rising at a pretty steady rate since 1900. Clearly the rise in temperatures up to the mid 20thC can have had little to do with CO2. In other words, we are back to the recovery from the Little Ice Age scenario. Is there any reason that warming in recent decades has not been caused by the same natural factors, which caused the earlier warming? 2) The rate of increase looks to have much slowed down, if not totally slowed, since the turn of the century. The record years were set in 1998 and 2010, (and yes, you’d be right to think of El Ninos). 3) There is clearly a big step up in 1998, raising the question of how much of the residual heat from that year’s El Nino has remained in the system. 4) There is a noticeable downturn in the 1950’s and 60’s, which follows the cold phase of the PDO. http://www.esrl.noaa.gov/psd/cgi-bin/gcos_wgsp/tsanalysis.pl?tstype1=20&tstype2=0&year1=&year2=2015&itypea=0&axistype=0&anom=0&plotstyle=0&climo1=&climo2=&y1=&y2=&y21=&y22=&length=&lag=&iall=0&iseas=1&mon1=0&mon2=11&Submit=Calculate+Results The PDO has been back up in positive territory in the last year, but would be expected to drop back down in due course. When it does, SST’s are likely to fall with it. The bottom line is that CO2 and other GHG simply cannot make any measurable difference to sea temperatures, given the massive heat capacity of the oceans. And there is certainly no known mechanics, whereby CO2 can just warm some parts of the ocean and not others. If sea temperatures really have risen in the last century as claimed, there is only one force powerful enough, and that is the sun.
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