Comparison of the claims by the Intergovernmental Panel on Climate Change (IPCC) of 1) “Most of the observed increase in global average temperatures since the mid-20th century is very likely” man made, and 2) “For the next two decades a warming rate of 0.2 deg C per decade is projected” are shown in this article not to be supported by the observed data, thus disproving IPCC’s theory of man made global warming.
FIRST IPCC CLAIM
In its Fourth Assessment Report of 2007, IPCC’s claim regarding global warming was the following :
Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.
Let us verify this claim using the observed data from the Climate Research Unit (CRU) of the University of East Anglia . In this claim, “mid-20th century” means year 1950. As a result, according to the IPCC, global warming since 1950 is mostly man made.
To verify the claim that global warming since 1950 is mostly man made, we may compare the global warming rate in degree centigrade (deg C) per decade in one period before 1950 to that of a second period after 1950 to determine the effect of the increased human emission of CO2. To be able to do this, we need to identify these two periods, which may be established from the Global Mean Temperature Anomaly (GMTA) data of the CRU.
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