Colder Stratosphere Thinning Arctic Ozone?

[meteo]

http://www.msnbc.msn.com/id/6889985/<br /><br /><font color="yellow">The ozone layer over the Arctic has thinned due to colder-than-normal temperatures, and "large scale losses" are likely if the cold conditions continue, a European research group reported.<br /><br />The research prompted the European Commission on Monday to issue a statement warning that “should further cooling of the Arctic stratosphere occur, increasing ozone losses can be expected for the next couple of decades.”<br /><br />It said the thinning could affect the Polar regions, Scandinavia and possibly as far down as central Europe.<br /><br />Neil Harris, a researcher with the European Ozone Research Coordinating Unit, said in a statement that "the meteorological conditions we are now witnessing resemble and even surpass the conditions of the 1999-2000 winter — when the worst ozone loss to date was observed."<br /><br />Overall temperatures in the Arctic ozone layer are the lowest in 50 years, and have been consistently low for the past two months, the group added.</font><br /><br />I found this article very interesting. We of course have to wait for some more research and conformation. Just a clarification this is not a controdiction of global warming. GHG's are expected to lower the temperature of the stratosphere.<br /><br /><font color="yellow">Greenhouse gases (CO2, O3, CFC) generally absorb and emit in the infrared heat radiation at a certain wavelength. If this absorption is very strong as the 15µm (= 667 cm-1) absorption band of carbon dioxide (CO2), the greenhouse gas can block most of the outgoing infrared radiation already close to the Earth surface. Nearly no radiation from the surface can, therefore, reach the carbon dioxide residing in the upper troposphere or lower stratosphere. On the other hand, carbon dioxide emits heat radiation to space. In the stratosphere this emission becomes larger than the energy received fro</font>

 

[earthseed]

Thanks, meteo. This provides a test for the hypothesis that climate warming is caused mainly by changes in solar radiation. Increased solar radiation should warm the stratosphere, while greenhouse warming will cool it. And the data says it is cooling.

 

[yurkin]

Thanks for the links. I head been wondering what was up with that. I also found this link. The graph showing a correlation of ozone whole and stratospheric temperatures is very interesting. Since O3 is a greenhouse gas its loss causes a cooling in the stratosphere. That cooling causes a further loss of ozone. And you get into one of those death spirals.<br /><br />http://www.theozonehole.com/climate.htm<br />

 

[meteo]

The loss of stratospheric ozone is partly responsible for the decrease in stratospheric temperature but the majority of the cooling cooling is thought to come from GHG's. I wouldn't expect the Arctic ozone hole to become worse than the Antarctic hole. Decreacing CFC output does help though.<br /><br />The radiative forcing from solar insolation is estimated to be 0.1-0.5 watts/m^2 since 1750; more from 1700 to present but still less than 1 watt/m^2. There is a lot of uncertainty in proxy estimates of TSI. <br /><br />*note "total solar irradiance" (TSI) is 1/5 terrestrial irradiation increasce.<br /><br />Estimates of well mixed GHG's (Halocarbons, CO2, CH4, NO2) is 2.43 watt/m^2 10% uncertainty. So that is significantly higher than the solar forcing.<br /><br />http://www.grida.no/climate/ipcc_tar/wg1/251.htm#6131

 

[meteo]

Thanks yurkin.

 

[earthseed]

Hi, meteo. I wonder if you know how what increase, in watts per square meter, in solar radiation is required to raise the Earth's average temperature by 1 degree C?<br /><br />I am trying to make a very basic climate model, so I can put the prospect of a doubling of carbon dioxide in the atmosphere into perspective. I find basic information surprisingly hard to come by.

 

[meteo]

http://www.grida.no/climate/ipcc_tar/wg1/216.htm#equ61<br />Try looking into the cited journal articles on the above page.<br /><br />http://www.grida.no/climate/ipcc/aviation/070.htm<br />IPCC (1996) uses a cental estimate of 0.6 K/(Watt/m^2)<br /><br />http://www.grida.no/climate/ipcc_tar/wg1/222.htm#635<br />Here are some equations for estimating radiative forcings.<br /><br />http://www.giss.nasa.gov/tools/modelE/<br />Fortran 90 source and and boundary/initial conditions for GCM.