[A-CG33] 中緯度大気海洋相互作用

[ACG33-01] Patterns of warm layer corrections to bulk sea surface temperature, with a focus on the western North Pacific

★Invited Papers

*Meghan F Cronin¹ (1.NOAA Pacific Marine Environmental Laboratory)

キーワード：diurnal cycle, SST, fronts, KEO, J-OFURO3, ERA5

There is growing recognition that to properly represent air-sea exchanges of heat, momentum and gasses (e.g., water vapor, CO₂ and O₂), it is necessary to resolve the temperature of the ocean skin, which is generally cooler (but can occasionally be warmer) than the bulk Sea Surface Temperature (SST) measured by in situ sensors. Within the Fairall et al. (2003) bulk flux algorithm, a cool-skin effect can be estimated for each time step, while the diurnal warm layer correction is estimated by running a simple 1-d model that is initiated at 6-AM and run while the surface fluxes are adding buoyancy to the surface layer. In this presentation, using data from the Kuroshio Extension Observatory (KEO), it is shown that this warm layer model can be modified to estimate the warm layer effect, including corrections to the skin temperature and corrections to the foundation SST below the warm layer, -- based upon daily-averaged air-sea fluxes and daily-averaged SST. This then allows use of the satellite-based J-OFURO3 fluxes to explore patterns of the warm layer effect. It is shown that the diurnal warming can have large-scale patterns, with frequent relatively large values north of the Kuroshio-Oyashio Extension SST front during summer, and in the transition zone between easterly trade winds and westerly winds. These patterns are compared to the skin minus foundation SST differences provided by the fifth generation European Centre for Medium-Range Weather Forecasts (ERA5) atmospheric reanalysis product.