Abstract. Uncertainties in quantitative estimates of the thermohaline circulation in any particular basin are large, partly due to large uncertainties in quantifying excess evaporation over precipitation and surface velocities. A single nondimensional parameter, γ ≡ q⁄hx⁄u is proposed to characterize the strength of the thermohaline circulation by combining the physical parameters of surface velocity (u), evaporation rate (q), mixed layer depth (h) and trajectory length (x). Values of γ can be estimated directly from cross-sections of salinity or seawater isotopic composition (δ18O and δD). Estimates of γ in the Red Sea and the South-West Indian Ocean are 0.1 and 0.02, respectively, which implies that the thermohaline contribution to the circulation in the former is higher than in the latter. Once the value of γ has been determined in a particular basin, either q or u can be estimated from known values of the remaining parameters. In the studied basins such estimates are consistent with previous studies.
How to cite. Berman, H., Paldor, N., and Lazar, B.: Quantifying thermohaline circulations: seawater isotopic compositions and salinity as proxies of the ratio between advection time and evaporation time, Ocean Sci. Discuss. [preprint], https://doi.org/10.5194/os-2017-58, in review, 2017.
The paper develops a new non-dimensional parameter that quantifies the degree to which the surface flow in a given area is thermohaline. The proposed parameter can be easily estimated from cross sections of either salinity or isotopes of oxygen or hydrogen. The parameter was estimated from publicly available data in two areas and in both it has yielded estimates of the rates of evaporation that are consistent with previous detailed observational studies.
The paper develops a new non-dimensional parameter that quantifies the degree to which the...