Articles | Volume 14, issue 2
Ideas and perspectives
26 Jan 2017
Ideas and perspectives |  | 26 Jan 2017

Ideas and perspectives: climate-relevant marine biologically driven mechanisms in Earth system models

Inga Hense, Irene Stemmler, and Sebastian Sonntag

Abstract. The current generation of marine biogeochemical modules in Earth system models (ESMs) considers mainly the effect of marine biota on the carbon cycle. We propose to also implement other biologically driven mechanisms in ESMs so that more climate-relevant feedbacks are captured. We classify these mechanisms in three categories according to their functional role in the Earth system: (1) biogeochemical pumps, which affect the carbon cycling; (2) biological gas and particle shuttles, which affect the atmospheric composition; and (3) biogeophysical mechanisms, which affect the thermal, optical, and mechanical properties of the ocean. To resolve mechanisms from all three classes, we find it sufficient to include five functional groups: bulk phyto- and zooplankton, calcifiers, and coastal gas and surface mat producers. We strongly suggest to account for a larger mechanism diversity in ESMs in the future to improve the quality of climate projections.

Short summary
Marine biota drives a number of climate-relevant mechanisms, not all of which are included in current Earth system models (ESMs) used for climate projections. We identify three classes of mechanisms and argue that, to adequately resolve these mechanisms and to ensure links to and feedbacks with other Earth system components, ESMs need to account for five marine organism groups.
Final-revised paper