Novel method for calculating typhoon genesis potential index index

Abstract

The invention relates to a novel method for calculating a typhoon genesis potential index index, which comprises the following steps of: quantitatively separating a typhoon wind field from atmosphericreanalysis data, and calculating the absolute vorticity of the troposphere low layer (850hPa) and the vertical wind shear of the troposphere high layer and the troposphere low layer (200hPa-850hPa);calculating the relative humidity at 600hPa and the potential typhoon intensity; and inputting a calculation result into an original GPI index so as to finally obtain an improved GPI index. Accordingto the novel method provided by the invention, a traditional GPI algorithm is optimized from the aspects of physical significance and a calculation scheme, the GPI index is calculated by utilizing element variables which do not contain typhoon weather system data such as a typhoon wind field, and then a purer index of potential contribution of an atmospheric marine environment background field totyphoon generation is obtained.

Description

technical field [0001] The invention relates to the technical field of typhoon climatology, in particular to a new method for calculating a typhoon potential generation index. Background technique [0002] Typhoon (typhoon), also known as tropical cyclone (TC), its potential generation index (GPI, Genesis PotentialIndex) is often used to estimate the weather-scale atmospheric system generated by various environmental field elements in the atmosphere and ocean, especially the image The combined impact of typhoon-like strong convective and hazardous weather system generation contributions. [0003] Typhoons mainly form and develop on the tropical ocean in summer and autumn. For typhoons affecting my country, most typhoons move west, northwest or north after forming in the tropical northwestern Pacific Ocean and South China Sea, and a few typhoons move east or southeast. Typhoons need to be in certain atmospheric and ocean environment conditions to generate, appear and develop...

AI Technical Summary

Problems solved by technology

Since the calculation of the contribution of various meteorological and oceanic elements in the diagnosis of typhoon generation environment is usually aimed at the period when typhoon generation is more frequent and activities are relatively active in summer and early autumn, at this time, the absolute vorticity item at 850hPa in the lower troposphere and the vertical wind at 200hPa minus 850hPa During the shear, the wind field of the upper and lower troposphere analysis data already contains a large amount of wind field information of the typhoon system, especially in the regions and periods of strong typhoon and super typhoon activity, the impact of typhoon wind field on the calculation results will be more obvious , therefore, the GPI index calculated under this situation is actually using the "variation characteristics of the typhoon system" to diagnose the "possibility of typhoon system formation", and the diagnosis results will have large deviations, even contrary to the "potential generation The wrong logic of the original design intention of "index"

Using this index to analyze and study typhoon activities in the field of atmospheric science will lead to an exaggeration of the contribution of the environmental field to the generation of typhoon in the analysis results, and at the same time, the judgment of the potential possibility of typhoon generation will be biased, resulting in a wrong diagnosis of the contribution of the environmental field to the generation of typhoon Accuracy will be greatly reduced

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