Assessment of IMERG-V06, TRMM-3B42V7, SM2RAIN-ASCAT, and PERSIANN-CDR Precipitation Products over the Hindu Kush Mountains of Pakistan, South Asia

Ali Hamza,Aminjon Gulakhmadov,Muhammad Kamran Shafi,Muhammad Naveed Anjum,Arslan Afzal,Xi Chen,Muhammad Jehanzeb Masud Cheema,Muhammad Azam

doi:10.3390/rs12233871

Abstract

In this study, the performances of four satellite-based precipitation products (IMERG-V06 Final-Run, TRMM-3B42V7, SM2Rain-ASCAT, and PERSIANN-CDR) were assessed with reference to the measurements of in-situ gauges at daily, monthly, seasonal, and annual scales from 2010 to 2017, over the Hindu Kush Mountains of Pakistan. The products were evaluated over the entire domain and at point-to-pixel scales. Different evaluation indices (Correlation Coefficient (CC), Root Mean Square Error (RMSE), Bias, and relative Bias (rBias)) and categorical indices (False Alarm Ration (FAR), Critical Success Index (CSI), Success Ratio (SR), and Probability of Detection (POD)) were used to assess the performances of the products considered in this study. Our results indicated the following. (1) IMERG-V06 and PERSIANN capably tracked the spatio-temporal variation of precipitation over the studied region. (2) All satellite-based products were in better agreement with the reference data on the monthly scales than on daily time scales. (3) On seasonal scale, the precipitation detection skills of IMERG-V06 and PERSIANN-CDR were better than those of SM2Rain-ASCAT and TRMM-3B42V7. In all seasons, overall performance of IMERG-V06 and PERSIANN-CDR was better than TRMM-3B42V7 and SM2Rain-ASCAT. (4) However, all products were uncertain in detecting light and moderate precipitation events. Consequently, we recommend the use of IMERG-V06 and PERSIANN-CDR products for subsequent hydro-meteorological studies in the Hindu Kush range.

Highlights

Reliable precipitation information is crucial for hydro-climatological studies, hydrological infrastructure planning, crop irrigation scheduling, and prediction of floods and droughts
Overall performance of Integrated Multi-Satellite Retrievals for Global Precipitation Measurement (IMERG)-V06 and PERSIANN-CDR was better than Tropical Rainfall Measuring Mission (TRMM)-3B42V7 and SM2Rain-Advanced SCATterometer (ASCAT). (4) all products were uncertain in detecting light and moderate precipitation events
All data sources indicated higher precipitation amounts over the low elevation areas

Summary

Introduction

Reliable precipitation information is crucial for hydro-climatological studies, hydrological infrastructure planning, crop irrigation scheduling, and prediction of floods and droughts. Ground-based weather radars and gauging-stations are considered as reliable sources of precipitation information [1]. Scarcity and uneven distribution of these ground-based stations in mountainous and remote areas, hamper the access to frequent measurements for many applications [2]. Uncertainties in ground-based measurements due to wind-induced errors, missing values, and heterogeneity, restrict their use [3,4,5]. Similar limitations of ground-based measurements exist in the Hindu Kush Mountains. The exploration of other reliable sources of uninterrupted precipitation data for such areas is indispensable

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Results

Discussion

Conclusion