A simple energy budget of the Earth for informing climate discussions

Friday, 19 December 2014
James C Wilson, Univ Denver, Denver, CO, United States and Daniel M Murphy, NOAA ESRL, Boulder, CO, United States
Discussions of recent climate change usually center around average surface temperature. Although temperature is important and easily interpreted, there is no conservation law for surface temperature as there is for energy. Energy conservation can therefore add to the discussion. For example, we are certain that increasing carbon dioxide is causing the Earth to retain energy. Any explanation of climate change must account for that energy. For the period when ocean data are available (1957-2013), the ocean heat content, IPCC AR5 estimates of forcing, and increased thermal emission from a warming Earth together produce a self-consistent energy budget. Emission from a warming Earth has balanced more greenhouse gas energy than has ocean heat uptake. Positive/negative cloud feedbacks on climate are consistent with an aerosol forcing larger/smaller than the central value.

With experience in using the energy budget in teaching an undergraduate course on climate science, we are trying to show the simplest possible energy budget that accurately conveys the science.