A reconciliation of empirical and mechanistic models of the air-sea gas transfer velocity

TitleA reconciliation of empirical and mechanistic models of the air-sea gas transfer velocity
Publication TypeJournal Article
Year of Publication2016
AuthorsGoddijn-Murphy L., Woolf D.K, Callaghan AH, Nightingale P.D, Shutler J.D
JournalJournal of Geophysical Research-Oceans
Volume121
Pagination818-835
Date Published2016/01
Type of ArticleArticle
ISBN Number2169-9275
Accession NumberWOS:000371432200047
Keywordsair-sea gas transfer; bubble plumes; bubbles; co2 exchange; dimethylsulfide; entrainment; flux; laboratory breaking-wave; ocean; parameterizations; whitecap coverage; wind-speed
Abstract

Models of the air-sea transfer velocity of gases may be either empirical or mechanistic. Extrapolations of empirical models to an unmeasured gas or to another water temperature can be erroneous if the basis of that extrapolation is flawed. This issue is readily demonstrated for the most well-known empirical gas transfer velocity models where the influence of bubble-mediated transfer, which can vary between gases, is not explicitly accounted for. Mechanistic models are hindered by an incomplete knowledge of the mechanisms of air-sea gas transfer. We describe a hybrid model that incorporates a simple mechanistic view strictly enforcing a distinction between direct and bubble-mediated transfer but also uses parameterizations based on data from eddy flux measurements of dimethyl sulphide (DMS) to calibrate the model together with dual tracer results to evaluate the model. This model underpins simple algorithms that can be easily applied within schemes to calculate local, regional, or global air-sea fluxes of gases.

DOI10.1002/2015jc011096
Short TitleJ Geophys Res-Oceans
Student Publication: 
No