Simple equations to estimate ratios of new or export production to total production from satellite‐derived estimates of sea surface temperature and primary production

Abstract

Two simple equations with sea surface temperature and total primary production as independent variables were used to estimate ratios of new or export production to total primary production (ef‐ratios) in the ocean. Both equations assume that ef‐ratios are negatively correlated with temperature in a linear manner and positively correlated with total primary production in a curvilinear manner characteristic of a Holling type II function. The two equations were parameterized based on different sets of field data: in one case entirely from estimates of new production based on nitrate uptake, and in the other case based on a comprehensive summary of new and export production estimates derived from a combination of techniques. Estimates of global export production based on satellite observations and use of the two equations were 9–13 Gt C per year. The form of both equations likely captures the principal effects of temperature and total production on ef‐ratios, and their mathematical simplicity should facilitate their prognostic application in climate change research and studies of the ocean's carbon cycle.