Developing a Surface-Based Ground Truth Dataset for Tropical Cyclones Outside of the Atlantic

Despite the lack of aircraft-based reconnaissance observations of tropical cyclones (TCs) over all global basins except the Atlantic, it may be possible to construct a validation database using available near-storm surface observations. TCs often pass over or very close to weather sensors from land stations, fixed marine sites, ships and drifting buoys. In the last 20 years or so there have been perhaps 100's of observations where a TC passed within a sufficiently close distance so that a reasonable estimate of the TC minimum sea level pressure (MSLP) could be derived. From this MSLP, a well-researched pressure-wind relationship such as the one proposed by Courtney and Knaff (2009) can then be applied to get an estimate of the associated maximum sustained surface winds (Vmax). Such a database of available observations along with appropriate metadata could be used to better validate satellite-based estimates of TC intensity, model forecasts, best tracks, etc. Since satellite-based algorithms are used to estimate the intensity of TCs in about 90% of cases globally, it is imperative that these methods are not only well-calibrated in general, but also validated in respective TC regions/basins.

This presentation is an attempt to scope the feasibility and effort needed to construct such a database. Some of these surface observations were publicly disseminated in real time, while others were not, and may exist only in various databases and/or reports (external and internal) written by respective TC warning agencies. To our knowledge there is no single source ‘library' that contains all of these observations to be browsed/utilized by the TC community. The hope is that the TC community will provide feedback on the feasibility and potential usefulness of this database as well as assist in sharing the availability of known observations.