Recent advances in observational support from space-based systems for tropical cyclones

Abstract

fiNys pkj n’kdksa ls m".kdfVca/kh; pØokrksa ¼Vh-lh-½ ds egRoiw.kZ izs{k.k miyC/k djkus esa ekSle foKkfud mixzgksa dh {kerkvksa ls lHkh ifjfpr gSA Hkw&LFkSfrd ekSle foKkfud mixzgksa ls izkIr n`’;] vojDr vkSj ty ok"i pSuyksa ls i`Foh ds es?kkPNknu ds yxkrkj  izkIr gksus okys fp= vkSj bu vk¡dM+ksa ls ek=kRed mRiknksa dks rS;kj djus dh {kerk lcls egRoiw.kZ gSA ekSle foKkfud mixzg v/;;u lgdkjh laLFkku           ¼lh-vkbZ-,e-,l-,l-½ foLdkasflu ;wfuoflZVh] ;w-,l-,- esa fiNys dqN o"kksZa esa fd, x, vuqla/kku ,oa fodkl iz;klksa ls m".kdfVca/kh; pØokrksa ds Lopkfyr fo’ys"k.k ds fy, ,d mUur M~oksjd rduhd ¼,-Mh-Vh-½ dk fodkl fd;k x;k gSA mRrjh vVykafVd vkSj dSfjfc;u lkxj esa vkus okys pØokrksa ds fo’ys"k.k ds fy, bl rduhd dk izpkyukRed mi;ksx fd;k tk jgk gSA tcfd Hkkjrh; leqnzksa esa ijEijkxr M~oksjd rduhd          ¼Mh-Vh-½ csgrj dk;Z djrh gS rFkkfi gekjs {ks= esa bl le; izpkyukRed vk/kkj  ij ,-Mh-,- dk mi;ksx bruk dkjxj ugha gSA

lh-vkbZ-,e-,l-,l- esa fiNys dqN o"kksaZ esa vuqla/kku ,oa fodkl iz;klksa ls mixzg ds vk¡dM+ksa ls izkIr fd, x, ek=kRed mRiknksa esa Hkh dkQh lq/kkj gqvk gSA bu mRiknksa esa fuf’pr :i esa m".kdfVca/kh; pØokrksa ds fo’ys"k.k esa lq/kkj vk;k gS vkSj ;s m".kdfVca/kh; pØokrksa dh Hkkoh xfr fn’kk dk iwokZuqeku djus ds fy, egRoiw.kZ lwpuk miyC/k djkrs gaSA Hkkjrh; mixzgksa ds vk¡dM+ksa ls orZeku esa izpkyukRed mRiknksa dh xq.koRrk midj.kksa ds vifj"—r foHksnu ij vk/kkfjr gSA vxys o"kZ ¼2013½ ls bulSV Ja[kyk ds u, mixzg ls vf/kd csgrj xq.koRrk ds vk¡dM+sa miyC/k gksus ls mRiknksa dh xq.koRrk esa vkSj vf/kd lq/kkj vkus dh vPNh laHkkouk gSA lw{e rajx vk/kkfjr midj.kksa ls izkIr vk¡dMsa+  Hkh m".kdfVca/kh; pØokr ds fo’ys"k.k ds fy, vfrfjDr mi;ksxh lwpuk miyC/k djkrs gSaA Åijh {kksHkeaMy esa m".k dksj folaxfr m".kdfVca/kh; pØokr dh rhozrk dk mi;ksxh lwpd gSA

Capabilities of meteorological satellites to provide vital observations on Tropical Cyclones (TC) are well known since more than last four decades. Most important are the frequent pictures of earth’s cloud cover in the visible, IR and water vapour channels obtained from Geostationary meteorological satellites together with the capability of generating a number of quantitative products from these data. R&D efforts of last several years at the Cooperative Institute of Meteorological Satellite Studies (CIMSS), Wisconsin University, USA have culminated into development of an Advanced Dvorak’s Technique (ADT) for automatic analysis of Tropical Cyclones. It is in operational use for analysis of North Atlantic and Caribbean Sea cyclones. It has been used on experimental basis at Satellite Meteorology Center, IMD while the conventional Dvorak Technique (DT) works well over the Indian seas, experience of using ADT does not permit at present its use on operational basis over our region.

R&D efforts of last several years at CIMSS have also resulted in lot of improvements in the Quantitative products derived from the satellite data. These products have certainly improved the analysis of TC and have provided useful information for predicting the future intensity/movement of TCs. Quality of currently operational products from Indian satellite data is limited by the coarser resolution of the instruments. With the availability of much better quality of data from the new satellite of INSAT series from year (2013) onward there is a good possibility of making further improvements in the quality of products. Data obtained from microwave based instruments also provides useful additional information for TC analysis. The warm core anomaly in the upper troposphere is a useful indicator of the TC intensity.