Physicist F. James Cripwell, a former scientist with the UK’s Cavendish Laboratory in Cambridge and now a member of the notorious list of 400 skeptical scientists, is of the opinion that we need an independent study to compare and contrast the four ways of measuring world temperature anomalies. Following is a copy of recent communications between the physicist and Marc Morano in which he explains why:
I write with respect to your latest communication about Alexander Cockburn. He seems to have made an important and fundamental error. He writes “While the world’s climate is on a warming trend…”. I do not believe the world’s climate is on a warming trend, though I cannot as yet prove this.
It is quite true that since somewhere around 1970, the world has warmed up. What is not clear is that, as of now, the world is still warming up. And, of course, “now” is moving. As time goes on, I believe the indications that the world has ceaased warming, and has started to cool, will become more and more obvious.
As I have noted before, there are four major agencies which measure average global temperature anomalies, and report them of a monthly basis. These are NASA/GISS, NCDC/NOAA, HAD/CRU and RSS/MSU.
The first, NASA/GISS data, shows that at present, average global temperatures are increasing. The other three show the opposite, that they are decreasing. I am suspicious that Jim Hansen and Gavin Schmidt are closely connected with the NASA/GISS data, but they are very competent scientists with impressive credentials.
If you ask for a linear least squares regression analysis, you find a linear trend of increasing temperatures. However, if you ask for a non-linear analysis, NASA/GISS shows an increasing trend, but the other three show that temperatures has passed through a maximum, and are now decreasing. What is missing is an independent study to compare and contrast the four ways of measuring world temperature anomalies, coming up with an opinion as to which is “best”, whatever this means.
Until we have such a stduy, we are unlikely to make any progress in this area. Or we must wait until the data showing that world temperatures are decreasing becomes too overwhelming to be ignored.