The image above comes from a post detailing the recently concluded conference on Quaternary Climate, entitled Epica 2008 in Venice, Italy. The image shows temperature variations, iron fluxes and carbon dioxide concentrations for the past 800,000 years from the deepest ice core ever extracted from Antarctica. Analysis of the core indicates that:
- the Earth's climate has been wildly oscillating between cold and warmth for at least 800,000 years, long before any sizable man-made intervention
- during that period, the record minimum has been reached around 20,000 years ago (10C less than today's); that's before agriculture
- the record maximum still belongs to around 120,000 years ago (15C more than today's); and that's before agriculture, too
- the concentrations of CO2 have depended on the amounts of iron in dust, with higher availability of iron resulting in lower amounts of atmospheric CO2
- and whilst temperatures have been at times warmer than today's, and at other times much colder, corals, mammals, birds, trees and the rest of the biosphere have chugged along nicely (in a relative way)
These results have potentially far reaching implications as they imply that the present high levels of increasing carbon dioxide may be less a function of excessive emissions and more the result of insufficient carbon sinks, deficient in iron dust.
The original source documentation summarizing the Epica 2008 conference is in Italian: not one of my languages. Since I have not (and can not) read the original for myself, I will restrict this post to what is above and hope that in the coming months the implications stemming from these ice core results inform the wider science of climate change and their implications discussed in more detail.
