Sensitivity analysis applied to two extreme rainfall events over Kerala using TIGGE ensembles

被引:3
作者
George, Babitha [1 ]
Kutty, Govindan [1 ]
机构
[1] Indian Inst Space Sci & Technol, Dept Earth & Space Sci, Valiamala 695547, India
关键词
CYCLONE INTENSITY; FLOODS; FORECASTS;
D O I
10.1007/s00703-022-00863-z
中图分类号
P4 [大气科学(气象学)];
学科分类号
0706 ; 070601 ;
摘要
The uncertainties associated with synoptic-scale atmospheric conditions of two catastrophic heavy rainfall events over Kerala, the southwestern coastal state of the Indian subcontinent, are quantified using Ensemble-based Sensitivity Analysis (ESA). Kerala witnessed two extreme rainfall events and floods during August 2018 (KF18) and August 2019 (KF19) causing large-scale destruction to life and properties. The synoptic features that are in common for the two events include the formation of a depression over the Bay of Bengal, a stronger low-level jet stream over the Arabian Sea, an off-shore trough, and circulations over the Western North Pacific (WNP). The present study attempts to identify the atmospheric flow features that are important to the predictability of these two heavy rainfall events using ESA. Further, the possible similarities and differences in the dynamics of the two events have been explored using an ensemble framework. Sensitivity analysis indicates that greater height fall needs to occur over the WNP to increase the KF18 precipitation, and any shift in the location of these features may affect the precipitation patterns over Kerala. Additionally, the results indicate that the circulations positioned farther east of its mean position are related to stronger precipitation over the response function region. However, the absence of sensitivity dipole suggests that the circulations over WNP have not impacted the KF19 event. The magnitude of positive sensitivity for low-level moisture-laden flow is stronger in KF19 than in KF18. The enhanced low-level flow in KF19 could be one potential reason for the development of deep convective clouds.
引用
收藏
页数:14
相关论文
共 33 条
  • [1] Comparing adjoint- and ensemble-sensitivity analysis with applications to observation targeting
    Ancell, Brian
    Hakim, Gregory J.
    [J]. MONTHLY WEATHER REVIEW, 2007, 135 (12) : 4117 - 4134
  • [2] Prediction of the August 2018 heavy rainfall events over Kerala with high-resolution NWP models
    Ashrit, Raghavendra
    Sharma, Kuldeep
    Kumar, Sushant
    Dube, Anumeha
    Karunasagar, S.
    Arulalan, T.
    Mamgain, Ashu
    Chakraborty, Paromita
    Kumar, Sumit
    Lodh, Abhishek
    Dutta, Devajyoti
    Momin, Imranali
    Bushair, M. T.
    Prakash, Buddhi J.
    Jayakumar, A.
    Rajagopal, E. N.
    [J]. METEOROLOGICAL APPLICATIONS, 2020, 27 (02)
  • [3] Orographic effect and multiscale interactions during an extreme rainfall event
    Baisya, Himadri
    Pattnaik, Sandeep
    [J]. ENVIRONMENTAL RESEARCH COMMUNICATIONS, 2019, 1 (05):
  • [4] Ensemble Sensitivity Analysis Applied to a Southern Plains Convective Event
    Bednarczyk, Christopher N.
    Ancell, Brian C.
    [J]. MONTHLY WEATHER REVIEW, 2015, 143 (01) : 230 - 249
  • [5] On scale interactions between the MJO and synoptic scale
    Dubey, Sarvesh
    Krishnamurti, Tiruvalam Natarajan
    Kumar, Vinay
    [J]. QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, 2018, 144 (717) : 2727 - 2747
  • [6] An optimized ensemble sensitivity climatology of Mediterranean intense cyclones
    Garcies, L.
    Homar, V.
    [J]. NATURAL HAZARDS AND EARTH SYSTEM SCIENCES, 2010, 10 (12) : 2441 - 2450
  • [7] Ensemble sensitivities of the real atmosphere: application to Mediterranean intense cyclones
    Garcies, L.
    Homar, V.
    [J]. TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY, 2009, 61 (03) : 394 - 406
  • [8] Ensemble sensitivity analysis of an extreme rainfall event over the Himalayas in June 2013
    George, Babitha
    Kutty, Govindan
    [J]. DYNAMICS OF ATMOSPHERES AND OCEANS, 2021, 93
  • [9] The 2018 Kerala floods: a climate change perspective
    Hunt, Kieran M. R.
    Menon, Arathy
    [J]. CLIMATE DYNAMICS, 2020, 54 (3-4) : 2433 - 2446
  • [10] Typhoon-Position-Oriented Sensitivity Analysis. Part I: Theory and Verification
    Ito, Kosuke
    Wu, Chun-Chieh
    [J]. JOURNAL OF THE ATMOSPHERIC SCIENCES, 2013, 70 (08) : 2525 - 2546