The energy that drives tropical cyclones comes from the heat storage in the ocean. Traditionally, the sea surface temperature (SST) has been used as a measure of the available energy in operational tropical cyclone intensity forecast models. However, the actual amount of heat storage in the ocean can be highly variable, even with the same SST. Thus, in order to more accurately forecast tropical cyclone intensity change, the sub-oceanic thermal structure must also be taken into account.

We present here the basis of a methodology to compute the tropical cyclone heat potential (TCHP) fields, a measure of the integrated vertical temperature in the upper ocean, using sea surface height data from satellite altimetry in combination with historical and hydographic observations. These fields, images and data, are computed globally since 1992 and are also presented via a web page.

Preliminary results indicate that the TCHP input to the operational Statistical Hurricane Intensity Prediction Scheme (SHIPS) can improve the accuracy of the intensity forecasts. However, a limitation of these predictions is that the SHIPS model was developed from a fairly small sample of cases with OHC observations available extending back to 1995 and only covering a fraction of the Atlantic tropical cyclone basin. In order to develop more reliable statistical relationships, we use this longer time series of TCHP fields that covered the entire Atlantic and east Pacific tropical cyclone basins. These analyses would enable the SHIPS model to include OHC effects in the entire area of responsibility of the National Hurricane Center. In additon, a version of the SHIPS model is also run operationally by the Joint Typhoon Warning Center (JTWC) in Honolulu. We hope that these fields will help to generalize their model to include OHC effects.