25th Conference on Hurricanes and Tropical Meteorology

Monday, 29 April 2002: 3:00 PM
Hurricane heat potential estimates from monthly versus seasonal temperature and salinity data
Sean R. White, NOAA/AOML/HRD, Miami, FL; and M. M. Mainelli, S. D. Jacob, and L. K. Shay
Poster PDF (166.2 kB)
Ocean heat potential calculations are available to enhance hurricane intensity predictions. Mainelli-Huber (MS thesis, 2000) calculates heat potential values on a 0.5o grid based on a two-layer model incorporating blended TOPEX/Poseidon and ERS-2 surface height anomalies, Reynolds Sea Surface Temperatures and climatological temperature and salinity profiles. The climatological profiles are based on combined NAVOCEANO Generalized Digital Environmental Model (GDEM), Levitus and Boyer (1994) and Boyer and Levitus (1997) climatological temperature and salinity datasets.

Using a two-layer model, heat potential calculations require a climatological background state of temperature and salinity to estimate the average density of each layer and hence reduced gravity. Because of the apparent discontinuities from month to month within the climatological data base, Mainelli-Huber used a hurricane season climatological data base defined by averaging temperature and salinity data from 1 June through 30 November. As climatological temperature and salinity profiles change on time scales less than the previously chosen hurricane season time scale, monthly climatological averages would provide a more representative background state of mesoscale ocean features, i.e. Western Boundary Currents, Loop Current, and Warm Core Rings. Using monthly climatological averages as the background state for heat potential calculations improve the representation of ocean features, factors important for hurricane intensity change.

The revised monthly climatologies on a 20 km grid are based on a combination of Miami Isopycnic Coordinate Ocean Model (MICOM) simulations, GDEM and Levitus climatological data. These new climatologies are combined with objectively analyzed surface height anomaly fields from the blended radar altimeter data sets. Central to these estimations is continuity in the heat potential calculations when storms occur between two months.

Supplementary URL: