Are there arguments for using ACRIM over PMOD, or vice-versa?
which points out:
"One of the greatest sources of difficulty in matching up the various satellite data sets is the “ACRIM gap.” The lauch of ACRIM II was delayed, due to the shuttle Challenger explosion, so there is a roughly 2-year gap between the end of the ACRIM I data set and the beginning of ACRIM II, from early/mid-1989 to late 1991. However, two different data sets are available which overlap both missions: HF (Nimbus 7) and ERBS. Unfortunately, these two show different trends during the ACRIM gap. Depending on which one accepts as more reliable, one gets decidedly different results when joining ACRIM I to ACRIM II."
Willson & Mordvinov (2003, Geophysical Research Letters, vol. 30, pg. 1199) conclude that ACRIM is the more accurate composite, but the author here argues that PMOD is better.
Anyone know of another argument for either?
According to RealClimate, they made some unrealistic assumptions. More realistic assumptions would result in a 0 and 10% solar irradiance contribution to the forcing since 1980 using PMOD and ACRIM, respectively.
Even if they are correct in their assumptions, it's quite interesting that the most they can attribute to solar irradiance is one-third of the forcing.