Sunday, January 4, 2009
Historic Solar Irradiance
The intensity of the sun varies over time. Two differant researches have developed a record from the year 843 to 1961; Yang and Bard. As can be seen, they agree fairly well, but diverge slightly during the oldest time period.
Since 1978, there are precision instruments on satellites that can measure the changes that occur over time. The 11 year sunspot cycle is evident by these measurements. A long term project of mine is to build a simplified climate model that includes solar variation, CO2, CH4, areosals levels and El Nino/Southern Oscillation to crudely model averge global tempertures.