Notes on Climate Change
1. Response to Readers: Notes on Climate Change
UPDATE: April 24, 2007
Dear Readers,
I would like to respond to a number of comments I have received on my Notes on Climate Change. Since it is not possible to respond to them all individually, I have prepared here a general response.
The purpose of my Notes on Climate Change is to point out some serious deficiencies in the recent IPCC Report. I would like to emphasize: (i) natural components are important and significant, so that they should not be ignored, (ii) it is insufficient to study climate change on the basis of data only from the last 100 years, (iii) it is difficult to make conclusions about causes of the temperature rise since 1975 until we can understand the rise from 1910 to 1940, (iv) the present GCM modelings are an attempt to simulate the IPCC hypothesis that the present warming (0.7°C/100years) is caused by the greenhouse effect, and thus, (v) because of these deficiencies, their future prediction is unreliable and uncertain.
If most of the present rise is caused by the recovery from the Little Ice Age (a natural component) and if the recovery rate does not change during the next 100 years, the rise expected from the year 2000 to 2100 would be roughly 0.5°C. Multi-decadal changes would be either positive or negative in 2100. This rough estimate is based on the recovery rate of 0.5°C/100 years during the last few hundred years. Note that this value is comparable with what IPCC hypothesize as the greenhouse effect. The greenhouse effect shown by GCMs should be carefully re-evaluated, if the present rise (0.7°C/100 years) contains significant natural components, such as those I suggest.
I have been emphasizing the importance of “natural components” during the last few years, but it seems that it is too vague to be getting the attention of many climatologists, GCM scientists, and IPCC scientists. I thought that a more concrete term is needed for this purpose. This is why I used the term “Little Ice Age”. I did not talk about causes of the Little Ice Age, because it is out of my own field. As far as the solar effects are concerned, I find many conflicting results in the literature.
I was director of the UAF Geophysical Institute for 13 years and then director of the International Arctic Research Center for 7 years. Although I am not a climatologist, it has been interesting to observe climatology from the point of view of an arctic scientist. In order for the field of climatology and IPCC to be healthy, I want to provide a few criticisms, which I hope are constructive.
Since I am not a climatologist, all the data presented in my Notes on Climate Change can be found in papers and books published in the past; that is why I do not want to publish Notes on Climate Change as a paper in a professional journal. It is very important for climatology to include some aspects of archaeology and anthropology in studying earth’s climate change, not just computer science. The IPCC climatology is a sort of ‘instant’ climatology. Old data, however inaccurate they maybe, could be more valuable in predicting future changes than the most accurate (instant) data from satellites. Finally, when I sent an early version of my Notes on Climate Change to several distinguished climatologists for their comments, one of them responded that his graduate student is now estimating the “rebounding rate” from the Little Ice Age, thus I suggested that his student should publish it at the earliest opportunity.
Regards,
Syun Akasofu
