The Atlantic Hurricane Database Re-Analysis Project: Results for 1851–1885

This presentation reports on the second year's work of a three year project to re-analyze the North Atlantic hurricane database (or HURDAT). The original database of six-hourly positions and intensities were put together in the 1960s in support of the Apollo space program to help provide statistical track forecast guidance. In the intervening years, this database - which is now freely and easily accessible on the Internet from the National Hurricane Center's (NHC's) Webpage - has been utilized for a wide variety of uses: climatic change studies, seasonal forecasting, risk assessment for county emergency managers, analysis of potential losses for insurance and business interests, intensity forecasting techniques and verification of official and various model predictions of track and intensity. Unfortunately, HURDAT was not designed with all of these uses in mind when it was first put together and not all of them may be appropriate given its original motivation. One problem with HURDAT is that there are numerous systematic as sell as some random errors in the database which need correction. Additionally, analysis techniques have changed over the years at NHC as our understanding of tropical cyclones has developed, leading to biases in the historical database that have not been addressed. Another difficulty in applying the hurricane database to studies concerned with landfalling events is the lack exact location, time and intensity at hurricane landfall. Finally, recent efforts into uncovering undocumented historical hurricanes in the late 1800s and early 1900s led by Jose Fernandez-Partagas have greatly increased our knowledge of these past events, which are not yet incorporated into the HURDAT database.

Because of all of these issues, a re-analysis of the Atlantic hurricane database is being attempted that will be completed in three years. As part of the re-analyses, three files will be made available:

* The revised Atlantic HURDAT (with six hourly intensities & positions)

** HURDAT meta-file: A text file with detailed information about each suggested change proposed in the revised HURDAT. *** A "center fix" file: This file is composed of actual observations of tropical cyclone positions and intensity estimates from the following platforms: aircraft, satellite, radar, and synoptic.

All changes made to HURDAT will be approved by a NHC Committee as this database is one that is officially maintained by them.

At the conference, results will be shown including a revised climatology of U.S. hurricane strikes back to 1851.