Jag vill gärna dela med mig av professor Ole Humlums otroligt gedigna genomgång av temperatur- och isdata. Ole Humlum visar sammanställningar av data från alla mätinstituten. Det är ett mycket intressant material. Så här skriver professor Humlum som inledning till materialet.
Please find attached a newsletter with meteorological information updated to April 2009. All temperatures are shown in degrees Celsius.
In the maps showing the geographical pattern of temperatures, the period 1998-2006 is used as reference period. The reason for comparing with this recent period instead of the official WMO ‘normal’ period 1961-1990, is that the latter period is affected by the relatively cold period 1945-1980. Almost any comparison with such a low average value will therefore appear as high or warm, and it will be difficult to decide if modern surface air temperatures are increasing or decreasing. Comparing with a more recent period overcomes this problem.
In the other diagrams the thin line represents the monthly global average value, and the thick line indicate a simple running average, in most cases a 37-month average.
The year 1979 has been chosen as starting point in several of the diagrams, as this roughly corresponds to both the beginning of satellite observations and the onset of the late 20th century warming period.
This month it is perhaps especially interesting -at least for people living in Europe – to compare the extent of above normal April temperatures in Europe with the extent of European news media coverage of this phenomenon.
All diagrams and figures are also available on http://www.climate4you.com/
Ladda ner materialet här. climate4you-april-2009