Systematically Merged Pacific Ocean Regional Temperature and Salinity (SPORTS) Climatology For Typhoon Intensity Forecasts

The Systematically merged Pacific Ocean Regional Temperature and Salinity (SPORTS) climatology was developed to estimate Ocean Heat Content (OHC) for the Northern Pacific Basin. A technique similar to the creation of the Systematically Merged Atlantic Regional Temperature and Salinity (SMARTS) climatology was used to blend temperature and salinity fields from the Generalized Digital Environment Model (GDEM) and World Ocean Atlas 2001 (WOA) at a 1/4º resolution. A 15-day running average was applied to the monthly GDEM and WOA climatologies to eliminate discontinuities when transitioning between months. The appropriate weighting for the blending of these two climatologies was estimated by minimizing the residual covariances across the basin and accounting for drift velocities associated with eddy variability using a series of 3-year sea surface height anomalies (SSHA) to insure continuity between the periods of differing altimeters. In addition to producing daily estimates of the 20º and 26 °C isotherm depths (and their mean ratios), mixed layer depth, reduced gravities, and OHC, the SSHA surface height anomalies product includes mapping errors given the differing repeat tracks from the altimeters and sensor uncertainties. This is especially important across the eddy-rich regime in the western Pacific Ocean.

Using SPORTS in concert with satellite-derived SST and SSHA fields from radar altimetry, daily OHC has been estimated from 2000 to 2011 using a two-layer model approach. Argo-floats, expendable probes from ships and aircraft, long-term moorings from the TAO array, and drifters provide approximately 267,540 quality controlled in-situ thermal profiles to assess uncertainty in estimates from SPORTS. This carefully constructed climatology creates an accurate estimation of OHC from satellite based measurements, which can then be used in tropical cyclone intensity forecasts in the North Pacific Ocean basin and building realistic ocean products for subsequent analyses.