Chaulk up another one under 'We dont even know what we dont know'

[IanC]

abstract-

The thermal structure and composition of the atmosphere is determined fundamentally by the incoming solar irradiance. Radiation at ultraviolet wavelengths dissociates atmospheric molecules, initiating chains of chemical reactions—specifically those producing stratospheric ozone—and providing the major source of heating for the middle atmosphere, while radiation at visible and near-infrared wavelengths mainly reaches and warms the lower atmosphere and the Earth’s surface1. Thus the spectral composition of solar radiation is crucial in determining atmospheric structure, as well as surface temperature, and it follows that the response of the atmosphere to variations in solar irradiance depends on the spectrum2. Daily measurements of the solar spectrum between 0.2 µm and 2.4 µm, made by the Spectral Irradiance Monitor (SIM) instrument on the Solar Radiation and Climate Experiment (SORCE) satellite3 since April 2004, have revealed4 that over this declining phase of the solar cycle there was a four to six times larger decline in ultraviolet than would have been predicted on the basis of our previous understanding. This reduction was partially compensated in the total solar output by an increase in radiation at visible wavelengths. Here we show that these spectral changes appear to have led to a significant decline from 2004 to 2007 in stratospheric ozone below an altitude of 45 km, with an increase above this altitude. Our results, simulated with a radiative-photochemical model, are consistent with contemporaneous measurements of ozone from the Aura-MLS satellite, although the short time period makes precise attribution to solar effects difficult. We also show, using the SIM data, that solar radiative forcing of surface climate is out of phase with solar activity. Currently there is insufficient observational evidence to validate the spectral variations observed by SIM, or to fully characterize other solar cycles, but our findings raise the possibility that the effects of solar variability on temperature throughout the atmosphere may be contrary to current expectations.[/QUOTE]Access : An influence of solar spectral variations on radiative forcing of climate : Nature

As often happens in science, when you measure a specific thing rather than the thing in general, it turns out to be a lot more different than you expected. More visible light (the kind that warms the surface) in this solar minimum. hmmm....who da thunk?

 

[IanC]

P.S- this means we have been getting more surface warming solar radiation even though the total solar radiation (TSI) is down. Perhaps there are many types of solar cycles, measured by more than sunspots and length.

 

[konradv]

P.S- this means we have been getting more surface warming solar radiation even though the total solar radiation (TSI) is down. Perhaps there are many types of solar cycles, measured by more than sunspots and length.

None of that changes the fact that GHGs absorb infra-red radiation. The more GHGs, the more trapped radiation. Since statistically only half would be re-emitted into space, where would the rest be going, but to heat the earth?

 

[IanC]

P.S- this means we have been getting more surface warming solar radiation even though the total solar radiation (TSI) is down. Perhaps there are many types of solar cycles, measured by more than sunspots and length.

None of that changes the fact that GHGs absorb infra-red radiation. The more GHGs, the more trapped radiation. Since statistically only half would be re-emitted into space, where would the rest be going, but to heat the earth?

Really? Care to quote a per centage figure on how much IR radiation doesn't make it out because of GHGs? Do you have any idea how much energy is carried by convection rather than radiation? Like the title says- we don't even know how much we don't know.