Both Lucia and Steve McIntyre beat me on this story, so I’ll defer to them. That’s what I get for going to dinner with relatives last night and sleeping in.
Below is a plot from McIntyre showing the RSS data compared to UAH MSU. Both are down significantly in June 2009 with UAH MSU at .001°C
RSS is down from 0.090C in May 2009 to 0.075C in June 2009
Steve McIntyre writes a little parody of the issue: RSS June – “Worse Than We Thought”
Lucia actually expected RSS to climb and has an analysis here
Even NCDC’s director Tom Karl has something to say about satellite data, read on.
Both of the datasets are available in raw form if you want t plot for yourself.
RSS (Remote Sensing Systems, Santa Rosa)
RSS data here (RSS Data Version 3.2)
UAH (University of Alabama, Huntsville)
Reference: UAH lower troposphere data
There had been some comments in the UAH thread earlier that May and June seem to have cycled lower in the UAH data set in recent years. It seems that RSS is following also.
I expect we’ll hear an announcement from NOAA/NCDC soon about it being the nth warmest June on record. They will of course cite surface data from stations like this one at the Atmospheric Sciences Department, University of Arizona at Tucson:
Here is a testimony in March 2009 before congress from NCDC’s director Tom Karl, where he complains about satellite data and the “adjustments” required:
It is important to note raw satellite data and rapidly produced weather products derived from satellite sensors are rarely useful for climate change studies. Rather, an ordered series of sophisticated technical processes, developed through decades of scientific achievement, are required to convert raw satellite sensor data into Climate Data Records (CDRs).
You mean “sophisticated technical processes” like these performed on raw surface temperature data at NCDC?