PNNL

Abstract

Abstract Carbonyl sulfide (OCS) and CO2 both diffuse through leaf stomata and are proportionally consumed by photosynthetic enzymes, enabling independent estimates of regional stomatal conductance disentangled from CO2 respiration fluxes. The largest sink of atmospheric OCS is destruction in plant leaves. While soils are typically a minor OCS sink, under some localized conditions soil OCS production has been observed. Here we present an empirical model to assess the impact of soil OCS production “hot spots” on the atmospheric OCS budget. We created biome-specific response curves characterizing soil OCS exchange using soil moisture and surface temperature alone. We further investigate the influence of regions with unknown soil OCS responses, e.g. tundra and the Tropics. This simple model demonstrates that soil OCS emissions do not hinder the use of OCS as a carbon cycle tracer of gross primary production (GPP) but account for a portion of the gap in the atmospheric OCS budget.