The Response of Damaging Winds of a Simulated Tropical Cyclone to Finite-Amplitude Perturbations of Different Variables
| العنوان: | The Response of Damaging Winds of a Simulated Tropical Cyclone to Finite-Amplitude Perturbations of Different Variables |
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| المؤلفون: | J. Henderson, S. M. Leidner, Christopher Grassotti, Thomas Nehrkorn, Ross N. Hoffman |
| المصدر: | Journal of the Atmospheric Sciences. 63:1924-1937 |
| بيانات النشر: | American Meteorological Society, 2006. |
| سنة النشر: | 2006 |
| مصطلحات موضوعية: | Atmospheric Science, Optimization problem, Data assimilation, Meteorology, Mesoscale meteorology, Environmental science, Perturbation (astronomy), A priori and a posteriori, Perturbation function, Calculus of variations, Tropical cyclone, Physics::Atmospheric and Oceanic Physics |
| الوصف: | Four-dimensional variational data assimilation (4DVAR) is an established data assimilation method that finds the finite-amplitude perturbation that best fits observations consistent with a priori information and model dynamics. The response of a simulated tropical cyclone to specially designed finite perturbations of selected model variables was studied with a modified version of 4DVAR. The usual goal of minimizing data misfits was replaced with a goal of reducing damaging surface winds at the end of six hours of forecast time. For this purpose a property value cost function based on topography was defined. The case studied was a 20-km simulation of a hurricane approaching the Hawaiian Islands. Each prognostic variable in turn—temperature, winds, humidity, vertical velocity, and perturbation pressure—and all prognostic variables at once were used as the control vector for the optimization problem. Of all prognostic variables examined, temperature and the horizontal wind were the most effective at reducing damaging surface winds. The wind-only perturbation was very similar to the wind component of the perturbation calculated when all prognostic variables were used at once. Calculated perturbations had scales of 0.25°C or 1 m s−1, but changes at a few grid points near the center of the storm were an order of magnitude greater. Vertical velocity and humidity perturbations alone were ineffective at reducing damaging winds. The perturbation pressure experiment failed to converge but did substantially reduce the damaging winds. |
| تدمد: | 1520-0469 0022-4928 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::c1eea5e18961679538df8fba1fdfa2c8 https://doi.org/10.1175/jas3720.1 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi...........c1eea5e18961679538df8fba1fdfa2c8 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15200469 00224928 |
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