In the above graph, the global average surface temperature anomalies from 1979 to 2008 (September update of five different metrics) are displayed. Climatepatrol regularly updates the past 30-year trendline of “global warming” and provides you with the average slope of three surface station metrics (Nasa,  Noaa, Hadley Centre) and two satellite metrics.

Results and comments

Climatepatrol updated the five datasets as follows: HadCrut3, Giss, NCDC (land ocean idices) and RSS and UAH (micro sound units). First of all, it is interesting to see that the contineous thinning out of surface stations as well as corrections in sea surface station measurement history resulted again in a slight increase in the warming bias of land and ocean surface measurements compared to the satellite and balloon data. When drawing a trend line from 1979-2008, which represents the average of the surface stations and grid projections, the slope of the same trendline was artifically increased by + 0,016°C per century due to corrections within the datasets since May 2008. This does not seem much. It is however not the first time that the warming bias increases because of decreasing the number of surface stations on land. Climatepatrol also has the old dataset of GISS “meteorological stations only”. Using the corrected version, the respective trendline of this dataset, which focuses on surface station measurements, increases by + 0,006°C per century only. The higher bias in the GISS land-ocean index of + 0,012°C per century suggests that corrections have been effected mainly in ocean surface measurements, at least in the case of GISS.

Detailed trend figures of the past 30 years (slope in °C per century)

   Dataset           1979-2008 May   1979-2008 Sept   1979-2008 Sept adjusted             

HadCrut3                  + 1,6256             + 1,5889               + 1,6059
Noaa-ncdc                + 1,6453             + 1,6046               + 1,6228
Giss-Nasa                  + 1,6408             + 1,6009               + 1,6125
RSS msu                    + 1,7227             …………               + 1,6823
UAH msu                   + 1,3325              …………               + 1,2792

Surface datasets        + 1,6372              + 1,5982             + 1,6137
Satellite units            + 1,5297               …………             + 1,4807
Overall average          + 1,5942              + 1,5512              + 1,5605

Tags: Giss-Nasa, global temperature, HadCRUT3, NCDC, noaa, RSS, UAH

This entry was posted on Saturday, October 18th, 2008 at 4:46 pm and is filed under English Categories, Global Temperature History. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.