User:Kenneth Cooke/Work in Progress

Jennifer Marohasy

Criticism

Mahorasy either does not understand the basic features of world weather or is being very selective in her use of knowledge in this subject. on the ABC Radio National program, Counterpoint [she said that]

...there has been cooling if you take 1998 as your point of reference. If you take 2002 as your point of reference then temperatures have plateaued. This is certainly not what you'd expect if carbon is driving temperature because carbon dioxide levels have been increasing but temperatures have actually been coming down over the last ten years. ...very unexpected not something that is being discussed. It should though be being discussed because it is very significant.

In actual fact this has been very much discussed and the post 1998 temperature trend are very well understood. For example from the [Goddard Institute of Space Studies] The Southern Oscillation and the solar cycle have significant effects on year-to-year global temperature change. Because both of these natural effects were in their cool phases in 2007, the unusual warmth of 2007 is all the more notable. It is apparent that there is no letup in the steep global warming trend of the past 30 years (see 5-year mean curve in Figure 1a). 'Global warming stopped in 1998' , has become a recent mantra of those who wish to deny the reality of human-caused global warming. The continued rapid increase of the five-year running mean temperature exposes this assertion as nonsense. In reality, global temperature jumped two standard deviations above the trend line in 1998 because the 'El Niño of the century' coincided with the calendar year, but there has been no lessening of the underlying warming trend.