Temporal characteristics of cloud tops during storm evolution

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00020699%3A_____%2F19%3AN0000067" target="_blank" >RIV/00020699:_____/19:N0000067 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Temporal characteristics of cloud tops during storm evolution

Popis výsledku v původním jazyce

Water vapor plays a very important role in radiative and thermodynamic processes in the atmosphere, and thereforea good knowledge of its distribution is crucial. In this study is described a method used for a detection of lowerstratospheric water vapor above cloud tops, so called brightness temperature difference (BTD) technique. Thistechnique is based on brightness temperature difference between water vapor absorption and infrared windowbands, assuming a thermal inversion above cloud top level. BTD techniques were investigated in many previousstudies and the most frequently offered explanation of positive BTD values above convective storms is a presenceof warmer water vapor in the lower stratosphere. We used BTD technique to propose an algorithm for the objectivedetection of anomalies in BTD field. These regions of higher BTD values not corresponding to lower brightnesstemperatures in windows band could be manifestation of locally increased amount of moisture. Such locallyincreased stratospheric water vapor have probably an origin in the troposphere and is a manifestation of thestratospheric-tropospheric exchange of water vapor.Other part of this study is focused on the application of the BTD technique and the proposed BTD anomalydetection algorithm. Temporal characteristics of parameters describing BTD (brightness temperature difference),BTD anomaly and infrared window brightness temperature were investigated during storms evolution on thedataset of over 300 storms from the area of Europe and north Africa. This dataset was used for studying abovementioned parameters for different groups of storms during their evolution.

Název v anglickém jazyce

Temporal characteristics of cloud tops during storm evolution

Popis výsledku anglicky

Water vapor plays a very important role in radiative and thermodynamic processes in the atmosphere, and thereforea good knowledge of its distribution is crucial. In this study is described a method used for a detection of lowerstratospheric water vapor above cloud tops, so called brightness temperature difference (BTD) technique. Thistechnique is based on brightness temperature difference between water vapor absorption and infrared windowbands, assuming a thermal inversion above cloud top level. BTD techniques were investigated in many previousstudies and the most frequently offered explanation of positive BTD values above convective storms is a presenceof warmer water vapor in the lower stratosphere. We used BTD technique to propose an algorithm for the objectivedetection of anomalies in BTD field. These regions of higher BTD values not corresponding to lower brightnesstemperatures in windows band could be manifestation of locally increased amount of moisture. Such locallyincreased stratospheric water vapor have probably an origin in the troposphere and is a manifestation of thestratospheric-tropospheric exchange of water vapor.Other part of this study is focused on the application of the BTD technique and the proposed BTD anomalydetection algorithm. Temporal characteristics of parameters describing BTD (brightness temperature difference),BTD anomaly and infrared window brightness temperature were investigated during storms evolution on thedataset of over 300 storms from the area of Europe and north Africa. This dataset was used for studying abovementioned parameters for different groups of storms during their evolution.

Druh

O - Ostatní výsledky

CEP obor

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OECD FORD obor

10509 - Meteorology and atmospheric sciences

Projekt

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Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů