Tropical Cyclone Ensemble Data Assimilation
Abstract
The ultimate goal of this project is to demonstrate that in the presence of tropical cyclones (TCs) a multi-scale approach for data assimilation can significantly enhance the analyses and the ensuing forecasts. Our multiscale approach is based on coupling a lower resolution global data assimilation system and a higher resolution limited area data assimilation system in the TC region. The coupled approach has the potential to lead to a better utilization of the computer resources in atmospheric modeling. Ours is the first attempt to use an ensemble-based, coupled global-limited-area data assimilation system to improve the analysis and the forecast of TCs and their effects on the larger scale atmospheric processes. In fact, to the best of our knowledge, we have been the only research group working on a data assimilation system that generates both global and limited area analyses. Our key scientific objective is to explore the potentials and the limitations of the coupled global-limited-area data assimilation approach. This research objective is particularly relevant for the numerical weather forecasting applications of the Navy, as the Fleet Numerical Meteorology and Oceanography Center (FNMOC) prepares both a global forecast and a larger number of limited are forecasts (more than 60) than any other forecast center in the world. In the first year of the project, we completed implementing our system on the North-Pacific region. In the current reporting period (the second year of the project) we carried out a large number of analysis/forecast experiments using different resolutions of the limited area component of the system. The resolutions we tested were 200 km, 100 km, 48 km, 36 km and 24 km. To asses the quality of the analyses and the forecasts, we verified them against the best track position and intensity estimates of the Joint Typhoon Warning Center (JTWC). The results of these experiments have been summarized in a Master of Science Thesis and a paper.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 2011
- Accession Number
- ADA557185
Entities
People
- István Szunyogh
Organizations
- Texas A&M University