Performance Evolution of a Satellite Rainfall Product as a Possible Input Data Choice for Hazard Assessment Models: a case study of Pakistan
Yawar Hussain1; Frédéric Satgé1; Hernan Martaniz-Carvajal1; Marie-Paule Bonnet2; Aderson Farias do-Nacimento3; Martin Cárdenas-Soto4; Henrique Llacer Roig5; Gulraiz Akhter6
1 University of Brasilia; 2 Institut de Recherche pour le Développement; 3 University of Rio Grande do Norte do Natal; 4 National Autonomous University of Mexico; 5 University of Brasilia, Brazil; 6 Quaid-i-Azam University, Islamabad, Pakistan,
Resumo
Rainfall is considered to be a prime driver in triggering of climate extremes (flooding and droughts) throughout the globe. For the management of economic, social and environmental impacts of these extremes, various Hazard Assessment Models (HAMs) available and proposed. Major barrier in the use of such HAMs lies in the preparation of their input data sets at fine spatial and temporal resolutions, which is usually not possible and practiced in the case of developing countries like Pakistan. This study is an attempt to provide an alternative choice for the preparation of rainfall estimates for the HAMs. In this study PERSIANN-RT satellite rainfall product is tested over Pakistan for year 2008-2010 and results of monthly time scale rainfall are compared with in situ data. Data comparison is done by continuous verification methods like statistical Bias varies from < -40 to > 30 and Correlation Coefficient (CC). The Cumulative Frequency Distribution (CFD) function gives us under and over estimation of SRE at different rainfall intensities. From this study it is concluded that PERSIANN-RT Satellite product accuracy in rainfall estimation is influenced by snow cover and topographic effects which should be taken under consideration beforeits application in different Hazard Assessment Models (HAM). KEYWORDS: Droughts, Flooding, Hazard Assessment, PERSIANN-RT, Pakistan 1 INTRODUCTION Rainfall is considered as an impetuous in triggering of Landsliding flooding and droughts, which in turn cast damages tohuman population, infrastructures and economic losses.Rainfall over high mountains is linked to flooding and agriculture in low land areas of Pakistan. Accurate, spatial and temporal estimations of rainfall especially, over mountainous regions are hampered by the tough terrains and extreme climatic constrains. Pakistan has agricultural economy which is dependent on water. Major portion of Gross Domestic Product (GDP) and employment is provided by the agriculture sector. The major source of water is provided by rain
Palavras-chave: Hazard Assessment; PERSIANN-RT; Droughts; Pakistan