Radiometric observations before and during a rain event at a tropical location
01 Dec 2011-pp 1-4
About: This article is published in IEEE Applied Electromagnetics Conference.The article was published on 2011-12-01. It has received 1 citations till now. The article focuses on the topics: Event (relativity) & Liquid water path.
TL;DR: In this article , the authors explored the characteristics of pre-monsoon rainfall over a tropical urban location, Kolkata have been explored utilizing ground-based observations, which is characterized by convective rain events and thunderstorms, mostly occurring from afternoon to night (15:30 IST − 21: 30 IST) span.
Abstract: • Pre-monsoon rainfall over Kolkata is categorized on the basis of time of occurrence. • Rain events are categorized as expected (14:30 IST-18:30 IST) and delayed (after 18:30 IST). • Small value of the IWV to LWP ratio results in significant precipitation for the delayed events. • Ground level temperature of the delayed events exhibits 1K higher values than the expected ones. • Variation of CAPE shows discernible increasing trend prior to two types of rain events. The annual rainfall amount over Gangetic West Bengal is predominantly determined by monsoon (June to September) and pre-monsoon (March to May) rain events. Consequently, such seasonal precipitation is directly linked to the socio-economic advancement of the area. In this paper, some characteristics of pre-monsoon rainfall over a tropical urban location, Kolkata have been explored utilizing ground-based observations. Pre-monsoon rainfall over Kolkata is characterized by convective rain events and thunderstorms, mostly occurring from afternoon to night (15:30 IST − 21:30 IST) span. Emphasis has been given to the set-in time of pre-monsoon rain events, based upon which they are classified as expected (14:30 IST − 18:30 IST) and delayed (after 18:30 IST). Efforts have been made to assess the sustaining atmospheric conditions (in terms of temperature, water vapour, liquid water content and instability parameter) associated with such rain events prevailing over two non-overlapping time spans of pre-monsoon season. The mean diurnal variations of integrated water vapour (IWV), liquid water path (LWP), and instability parameter, namely, convective available potential energy (CAPE) during the expected and delayed rain event dates show distinct intensity in the increasing trends prior to the respective rainfall peaks. It has been observed that for the delayed events, the temperature difference between ground and 2000 m altitude begins to fall at a later part of the evening in comparison with the expected ones. Overall the investigated parameters exhibited distinguishable nature of variations for the two classes of rain events over the study location.
TL;DR: In this paper, the authors review some of the developments in this area, describe basic principles and results of field experiments, including the recent ONSAM-experiment, and summarize two years' performance of the NOAA Profiler.
Abstract: Remote sounding of atmospheric variables by groundbased microwave radiometers has proved to be useful for several applications. These radiometers are used to measure profiles or integrated values of temperature, water vapor, and cloud liquid. The information provided is useful in meteorology, astronomy, geodesy, communication, for correction of space observations, for atmospheric research, etc. It may be possible to combine ground-based radiometers, satellite-borne radiometers, and VHF radars to form a meteorological network which provides profiles of temperature, humidity, and wind continuously in time. This paper will review some of the developments in this area, describe basic principles and results of field experiments, including the recent ONSAM-experiment, and summarize two years' performance of the NOAA Profiler.