R. Mastanaiah ¹, P. S. Brahmanandam ², G. Uma ², A. Narendra Babu ³, K. Krishna Reddy ¹

Affiliations
1 Department of Physics, Yogi Vemana University, Kadapa - 516003, Andhra Pradesh, IN
2 Shri Vishnu Engineering College for Women, Bhimavaram - 534202, Andhra Pradesh, IN
3 Department of Electronics and Communication Engineering, LBR College of Engineering, Mylavaram - 521230, Andhra Pradesh, IN

Abstract

Objectives: To study the seasonal variations of two important atmosphere stability indices, i.e. Convective Available Potential Energy (CAPE) and Convective Inhibition (CIN) for the selected years, i.e. from 2007 to 2012 using the COSMIC (Constellation Observing System for Meteorology, Ionosphere, and Climate) Radio occultation (RO) technique. Methods/Analysis: We used the COSMIC RO technique as we consider that it provides more accurate, all-weather, round the-clock and global coverage of the lower atmosphere and ionosphere constituents with unprecedented resolutions. Further, we used the lower atmosphere database provided by the COSMIC RO technique in order to study the above two parameters (CAPE & CIN). Findings: It was found that, for the very first time, the consistency of wavy nature in CAPE seasonal trends which are confined to northern and southern hemispheres alternatively. The wavelike nature in CAPE trends seems to be following Inter- Tropical Convergence Zone (ITCZ) movement and, in such case, the CAPE trends may be useful to ascertain the ITCZ movements during different seasons of a year and the CAPE magnitude shows higher values over land than oceanic regions, which confirms the consistency of their calculations. In this regard, the trends of both CAPE and CIN have shown a close bimodal distribution. Applications/Improvement: As a result, we find better correlations of both CAPE and CIN computed through the atmospheric data measured with the COSMIC RO and collocated Radiosonde technique when the profile data are reaching to the near-surface of the Earth.

Keywords

Convective Available Potential Energy (CAPE), Convective Inhibition (CIN), GPS RO Technique, ITCZ.

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V. Naveen Kumar ¹, P. S. Brahmanandam ², M. Purnachandra Rao ³, G. Anil Kumar ⁴, K. Samatha ³, L. Rupa Dhanasri ⁵

Affiliations
1 Department of Basic Science, Gudlavalleru Engineering College, Gudlavalleru - 521356, Andhra Pradesh, IN
2 Departmentof Basic Science, Shri Vishnu Engineering College for Women, Bhimavaram - 534202, Andhra Pradesh, IN
3 Departmentof Physics, Andhra University, Visakhapatnam - 530003, Andhra Pradesh, IN
4 School of Renewable Energy and Environment, JNTUK, Kakinada - 533003, Andhra Pradesh, IN
5 Department of ECE, Shri Vishnu Engineering College for Women, Bhimavaram - 534202, Andhra Pradesh, IN

Abstract

Objectives: Although several methods are available to identify ABLHeight (ABLH), a comprehensive study on the usage of different analytical methods has not been reported widely, particularly on global databases. Methods/Analysis: In this research, we use various analytical methods including, gradient, double gradient and logarithmic gradient to estimate ABLH during two months (March and April 2013) period and applied those methods on COSMIC Radio Occultation retrieved temperature profiles to estimate ABLH. Findings: The estimated ABLHs are arranged in order to present them globally and diurnally that clearly show a few distinct features. Mainly, land and desert areas are associated with higher ABLH during daytime hours. Cold land areas (Arctic and Greenland) show relatively lower magnitudes and reverse are the cases with ABLH over cold oceans (Antarctic oceans). Most importantly, a distinctive diurnal feature is observed with a peak at sharp noon time and relatively lower values in the night time, which indicate both convective and stable layers, have evolved based on the ambient conditions that would exist during the day and nighttime ambient conditions. However, morning and evening transitions are not found in diurnal variations. Applications/Improvements: It is found that both gradient and logarithmic methods are able to find accurate ABLH, though still a great room exists to verify various other methods in finding ABLH.

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