Improving one uncertainty in climate models.

Started by aristaeus63, 10/29/2008 06:51PM
Posted 10/29/2008 06:51PM | Edited 10/29/2008 11:18PM Opening Post
I read an article in the October 21 issue of EOS titled "New Satellites help Quantify Carbon Sources and Sinks". The new satellites are the NASA DESDynl and the ESA BIOMASS missions. From the article "Deforestation and forest degradation account for between 7% and 30% of total anthropogenic carbon emissions." The uncertainty stems from rates of deforestation, carbon stock biomass, soil calculations and changes in the biomass and soil within a forest. This uncertainty also affects climate models as they can only use the best data on hand.

Not all forests are equal. Tropical forests are bigger carbon sinks than mid latitude forests. Calculations for deforestation and biomass are currently done with a few older satellites and with on ground observations. The definitions of forests vary. Also when deforestation occurs it does not always get counted, and if it does, an average biomass is often used to calculate the carbon emissions.

An example of how this uncertainty happens is: "If forests are defined as having 20% tree cover, for example, the carbon released in reducing cover from 100% (tree cover) to 20% will not be counted as deforestation. And with a definition of 80% tree cover, the carbon emitted in reducing tree cover from 79% to zero will also not be counted."

The new missions will be capable of directly measuring above ground carbon stocks and biomass. The reduction in uncertainty will come from being able to compare an area over time and see whether the carbon stocks are decreasing (deforestation) or increasing (reforestation). "Assigning an accurate estimate of biomass to the forests that are actually deforested will reduce the uncertainty of carbon emissions by as much as a factor of 2."

Andreas

NASA Mission
http://desdyni.jpl.nasa.gov/

ESA Mission
http://www.esa.int/esaCP/SEMHQH9ATME_Protecting_0.html



DSOs observed:
NGCs 2005, ICs 103, Other 70, Palomar GCs 6, Abell PNs 12, Herschel 400: 316.
Equipment
Celestron CPC 1100, Lunt 60mm Ha Solar Scope
Posted 10/29/2008 08:46PM #1
Andreas not only deforestation a source of CO2 emissions, but you are also removing a sink for CO2, so deforestation is doubly dangerous