Observational constraints on the vertical distribution of instantaneous ozone radiative forcing in chemistry climate models

Tropospheric ozone is at the nexus of chemistry and climate through its role as a greenhouse gas, air pollutant, and regulation of the oxidative capacity of the atmosphere. The IPCC AR4 reports that radiative forcing of tropospheric ozone as the third most uncertain, the magnitude of which is dominated by preindustrial emissions and spatio-temporal distribution. We show the potential of observations from the NASA Tropospheric Emission Spectrometer (TES) of tropospheric ozone profiles and instantaneous vertical radiative forcing sensitivity (W/m^2/ppb) to constrain chemistry-climate models under all-sky conditions. Comparisons with TES generally show a high bias in ECHAM5-MOZ, a low bias in GISS, and a vertically dependent bias for AM2 globally. These biases can result in regionally specific differences between .5 to -.5 W/m2 for August 2006. We explore the implications of these differences for chemistry-climate projections.