Here you go, Steve, Below is the post Lee wrote in this chain on Friday. Very informative, as usual.
One of the core tenants of your belief that anthropogenic climate change is a farce seems to be that our records cover but 100 years. I'm curious if that skepticism extends to the many other trends we see today. How about the extinction event we are currently witnessing? We know far more about the biodiversity of the planet now than we did 100 years ago. Is the current wave of extinctions an artifact or our increased knowledge? (this and the following questions are rhetorical) What about the decline in the productivity of the World's fisheries? We didn't have a census of fisheries 100 years ago and we still don't sample the entire ocean. There are countless examples of types of information for which there are data sets of 100 years or less. If none of the trends we see in those data sets is reliable - oh brother.... If some are and some aren't, I'm curious to know what sort of mathematical rubric could be applied to know the reliable ones from the unreliable ones. Again, Lee's post is below, if you care to read it. Josh Josh: We have good direct records of atmospheric CO2 that go back 800,000 years. During that time, the CO2 content of the atmosphere has had a major cycle with peaks around 2x the lowest levels 8 times, and in each case the temperature change has been about 3 degrees C (5.4 degrees F). At this time we are well beyond the highest CO2 concentrations in the 800,000 year record. When we balance the various forcings on the climate we have: CO2, methane and other greenhouse gases, positive forcing (as established by Arrhenius in 1896, and confirmed repeatedly since then each time better equipment that can make more accurate measurements has been developed), black soot (positive forcing), human aerosols (negative forcing), albedo changes (net positive forcing in a warming climate due to shrinking ice sheets and snow cover), and change in energy output from the sun which goes up and down a tiny amount, but had a tiny net positive effect in the last 100 years, the overall net effect is positive, i.e. towards higher temperatures, and CO2 has a growing proportion of that positive forcing, easily dwarfing changes in the sun. We know that the current rise in CO2 is not one of the natural cycles observed in the 800,000 year record because CO2 derived from fossil fuel burning has a unique isotopic signature compared to carbon derived from other sources, which is showing up in the atmosphere. The volume of CO2 derived from fossil fuel burning (minus that that goes into the ocean and the vegetation) is equivalent to the annual increase in CO2 content of the atmosphere, and the annual upward step in CO2 content corresponds to known measures of economic activity (i.e. the increase in the Keeling curve is smaller in years with recessions, and smaller in earlier years of the record when the economy was smaller--the annual increase throughout the record is proportional to the amount of fossil fuels burned in a given year). Also, the long-term natural temperature trend over the last few thousand years has been downwards, and would be expected to continue downwards in the absence of human influence. As was pointed out in 1977, cycles in the earth's orbital parameters are changing the distribution of solar energy across the earth's surface in such as way as to start a long term downward trend in temperature towards the next glacial period. However, the human/CO2 influence at this point is pushing in the opposite direction with much greater magnitude. With regard to climate models--they are really doing quite well. In 1988, James Hansen published predictions for CO2 content of the atmosphere and the resulting temperature increase through the year 2020, based on the GISS (Goddard Institute for Space Studies) global circulation model. A comparison was made of the predictions and actual observed temperatures for the year 2005, and the predictions first published in 1988 matched 2005 almost perfectly (the observed temperature increase was slightly larger than predicted). Todays models are much better than the ones available in 1988. The models run without the CO2 and other human effects (with only natural forcings included) cannot duplicate the observed temperature changes during the last century, while they can come close with CO2 included. These results have been duplicated with 16 different global circulation models from various research labs around the world. In addition, as Hansen has recently pointed out, the same predictions for worldwide mean temperature can and have been made via direct physics with a simple formula on a hand calculator, or as Arrhenius did with amazingly accurate results in 1905, with paper and pencil. The problems arise in trying to predict what might happen in a given location and time (i.e. weather rather than climate--weather is less predictable). Regarding university research funding, there is an emphasis on climate change, but the majority of funding is still given out for other topics. Its hard to see how anyone would have to do climate change research just to get funding. I managed to be ranked among the top 1% of all scientists in the world as of 2006 without publishing a single paper on global warming. I am doing some global warming research now, but so far have not been able to get any funding for it. Lee --~--~---------~--~----~------------~-------~--~----~ Eastern Native Tree Society http://www.nativetreesociety.org Send email to [email protected] Visit this group at http://groups.google.com/group/entstrees?hl=en To unsubscribe send email to [email protected] -~----------~----~----~----~------~----~------~--~---
