Understanding the Drivers of Extreme Precipitation Events in Pakistan

Abstract

Pakistan has been highly affected by the impacts of climate change, which have resulted in abnormal weather events. Over the past 14 years, Pakistan has witnessed two large-scale floodings (in 2010 and 2022) caused by abnormal precipitation events, which led to the loss of precious lives. The stark reality is that considering the geographical location of Pakistan, large-scale floodings caused by high precipitation events are likely to pose a threat in the future as well. This study investigated the drivers for extreme precipitation events in Pakistan that led to these large-scale floodings. Data for 54 years of atmospheric variables from 1970-2023 were evaluated. The study selected a predictand region (28-34 N, 67-73 E) that had a wide representation of abnormal weather events in Pakistan, particularly the floods in 2010 and 2022. Subsequently, analysis of the atmospheric variables was done at long term means (LTM), including their composite anomalies, to select predictors linked to high precipitation. Later, correlation analysis between predictand and potential predictors led to our finalized set of predictors, including 850 hPa GPH over the Nepal and Red Sea at zero lead, SST over the South Central Indian Ocean and Southwest Indian Ocean (one month lead). Finally, statistical analysis using a logistic regression model was undertaken along with accuracy analysis using precipitation thresholds.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 2023
Accession Number
AD1225366

Entities

People

  • Hassan Ilyas

Organizations

  • Naval Postgraduate School

Tags

Fields of Study

  • Environmental science

Readers

  • Atmospheric Science/Meteorology
  • Seismology