# Presentation: 547542

## The Impact of Satellite Data on Real Time Statistical Tropical Cyclone Intensity Forecasts Joint Hurricane Testbed Project

**Mark DeMaria, NOAA/NESDIS/ORA, Fort Collins, CO**** ****Michelle M. Mainelli, NOAA/NCEP/TPC, Miami, FL  **
**Lynn K. Shay, University of Miami, MPO/RSMAS, Miami, FL **
**John A. Knaff, CSU/CIRA, Fort Collins, CO **** ****James P. Kossin, UW/SSEC/CIMSS, Madison, WI**
- Presented At The Inter-Departmental Hurricane Conference
- March, 2003 Miami, FL

## Project Overview

- _Goal_: To determine if satellite data (GOES and satellite altimetry) can improve the intensity forecasts from the statistical-dynamical SHIPS model
- _Method:_ Parallel version of SHIPS with satellite input was run in real-time for 2002 Atlantic season
- Parallel version also developed for East Pacific, and run after the season with operational input
- _Evaluation_: Compare operational and parallel SHIPS forecasts for Atlantic and east Pacific

## The SHIPS Model

- Statistical-dynamical model predicts tropical cyclone max winds 0-120 hr
- Climatology, persistence, SST and atmospheric (vertical shear, momentum fluxes, etc) predictors
- Reynold’s SST, NCEP global forecasting system
- Empirical decay for portion of track over land
- Run 4 times per day, initiated by the ATCF
- Track from adjusted 6-hour old NHC official forecast
- LBAR track when no official forecast available
- Developed from 1989-2001 sample

## Parallel Version of SHIPS

- Predictors from GOES Imagery
- % IR brightness temperature < -20 C, R=50-200 km
- Std. Dev. of IR temp, R=100-300 km
- Predictors from satellite altimetry data
- Ocean Heat Content (OHC) exceeding 50 KJ/cm2 averaged along the forecast track
- Method developed by Shay/Mainelli
- Atlantic only
- Developed using 1995-2001 sample
- Predicts correction to operational SHIPS forecast
- Dependent data suggest ~5% max improvement at 48 hr

## Sample GOES Imagery and OHC Analysis

- Hurricane Floyd 14 Sept 1999                 OHC 26 Sept 2002

## 2002 Evaluation 

- “New” NHC verification rules
- Depressions, subtropical included
- Extra-tropical, wave, remnant-lows excluded
- Only Decay-SHIPS forecasts considered since many storms were affected by land
- Verification samples
- Atlantic real-time forecasts (Dolly-TD14)
- Atlantic re-runs (all storms)
- No GOES or OHC, GOES only, OHC only, GOES+OHC
- East Pacific re-runs (all storms)
- No GOES, GOES
- Re-runs used all operational input
- Very similar, but not identical to real-time forecasts

## Verification of Real-Time 2002 Atlantic Forecasts

## Improvement of Parallel vs. Operational SHIPS(Real-time 2002 Atlantic Forecasts)

- N:    238   219    199    185              158             133            118

## Contributions from GOES/OHC(Atlantic Forecast Re-runs)

- N:   268    244    219    197   178    163   149     139    132  123

## Verification of Re-Run 2002 East Pacific Forecasts

## Improvement of Parallel vs. Operational SHIPS(Re-Run 2002 East Pacific Forecasts)

## Conclusions

- Atlantic
- Real-time 12-72 h SHIPS improved by up to 5%
- Statistically significant at 90% level 12-36 hr
- GOES and OHC both contribute to improvement
- Some degradation at day 4 and 5
- East Pacific
- Real-time 12-72 h SHIPS improved by up to 8%
- Statistically significant at 90% level 12-72 hr
- Some degradation at day 4 and 5
- Suggestions to JHT:
*Study individual forecasts in more detail*
*Add 2002 cases to developmental sample*
*Run in parallel again in 2003*

## Future Plans

- On average, SHIPS model has skill out to 72 hours (10-15% over SHIFOR, 1997-2002)
- Wide variation in performance from storm to storm
- Primary limitations
- Upper-end of rapid intensification
- 100-140 kt range
*Add recon data to SHIPS (new JHT proposal)*
- “False Alarm” storms
- Lack of thermodynamic information?
*Analyze new hyperspectral (AIRS) tropical soundings*

## Operational SHIPS forecasts forAlberto 2000 and Lili 2002