First Assessment of Continental Energy Storage in CMIP5 Simulations

Abstract

Abstract Although much of the energy gained by the climate system over the last century has been stored in the oceans, continental energy storage remains important to estimate the Earth’s energy imbalance and also because crucial positive climate feedback processes such as soil carbon and permafrost stability depend on continental energy storage. Here for the first time, 32 general circulation model simulations from the fifth phase of the Coupled Model Intercomparison Project (CMIP5) are examined to assess their ability to characterize the continental energy storage. Results display a consistently lower magnitude of continental energy storage in CMIP5 simulations than the estimates from geothermal data. A large range in heat storage is present across the model ensemble, which is largely explained by the substantial differences in the bottom boundary depths used in each land surface component. , Key Points The continental energy storage from 1950–2000 is assessed in simulations from 32 CMIP5 models All CMIP5 simulations underestimate the continental heat storage relative to estimates from observed geothermal data The shallow subsurface depth of CMIP5 land surface models falsely limits subsurface heat storage and thermal memory