If you recall my recent post "Science? I think not!" I presented links to data showing how climate was affected by solar radiation way more than any human controlled factors. Well, more evidence is on the way. According to NASA scientists in the article "Getting to the SORCE of Climate Change":
...the phenomenal interconnectedness of each aspect of our world leads to misconceptions and incomplete notions regarding climate change. On Jan. 25, 2003 NASA will be launching the SOlar Radiation & Climate Experiment, or SORCE spacecraft...
More info about the SORCE (SOlar Radiation & Climate Experiment) satellite can be found at NASA's web site. A good summary is found at Ar Technica's post about a recent paper in Nature [link to the paper is with the article but you have to pay to read it - boo]:
In a recent issue of Nature, Joanna Haigh and colleagues report that the largest deviation from predicted activities of the solar cycle occurred between 2004 and 2007, when the Sun’s activity was in a decline. Data from the Spectral Irradiance Monitor (SIM) instrument showed a four- to six-fold larger decrease in ultraviolet irradiation, and an increase in visible irradiation, compared to predictions from a leading solar model. A second instrument on the SORCE satellite, the Solar Stellar Irradiance Comparison Experiment (SOLSTICE), also observed the drastic variations in the ultraviolet region.
The wavelength of solar irradiation determines what part of the atmosphere is affected the most. Ultraviolet irradiation leads to chemical reactions that produce more ozone in the stratosphere and warm up the stratosphere and mesosphere. Irradiation in the visible wavelengths penetrates further, leading to heating of the Earth’s surface, troposphere, and lower stratosphere.
Of course, this is still data gathering, but it will be nice to have some actual facts inserted into the climate debate, rather than computer simulations.