A semi-analytical model for water vapor, temperature, and surface-albedo feedbacks in comprehensive climate models
- Nicole Feldl
- Timothy Merlis
Radiative feedbacks govern the Earth’s climate sensitivity and elucidate the geographic patterns of climate change in response to a carbon-dioxide forcing. We develop an analytical model for patterned radiative feedbacks that depends only on changes in local surface temperature. The analytical model combines well-known moist adiabatic theory with the radiative-advective equilibrium that describes the energy balance in high latitudes. Together with a classic analytical function for surface albedo, all of the non-cloud feedbacks are represented. The kernel-based analytical feedbacks reproduce the feedbacks diagnosed from global climate models at the global, zonal-mean, and seasonal scales, including in the polar regions, though with less intermodel spread. The analytical model thus provides a framework for a quantitative understanding of radiative feedbacks from simple physics, independent of the detailed atmospheric and cryospheric responses simulated by comprehensive climate models.