Terrestrial water storage in African Hydrological regimes derived from GRACE mission data: Intercomparison of spherical harmonics, mass concentration, and Scalar Slepian methods

Ashraf Rateb, Chung Yen Kuo, Moslem Imani, Kuo Hsin Tseng, Wen Hau Lan, Kuo En Ching, Tzu Pang Tseng

Research output: Contribution to journalArticlepeer-review

10 Citations (Scopus)

Abstract

Spherical harmonics (SH) and mascon solutions are the two most common types of solutions for Gravity Recovery and Climate Experiment (GRACE) mass flux observations. However, SH signals are degraded by measurement and leakage errors. Mascon solutions (the Jet Propulsion Laboratory (JPL) release, herein) exhibit weakened signals at submascon resolutions. Both solutions require a scale factor examined by the CLM4.0 model to obtain the actual water storage signal. The Slepian localization method can avoid the SH leakage errors when applied to the basin scale. In this study, we estimate SH errors and scale factors for African hydrological regimes. Then, terrestrial water storage (TWS) in Africa is determined based on Slepian localization and compared with JPL-mascon and SH solutions. The three TWS estimates show good agreement for the TWS of large-sized and humid regimes but present discrepancies for the TWS of medium and small-sized regimes. Slepian localization is an effective method for deriving the TWS of arid zones. The TWS behavior in African regimes and its spatiotemporal variations are then examined. The negative TWS trends in the lower Nile and Sahara at −1.08 and −6.92 Gt/year, respectively, are higher than those previously reported.

Original languageEnglish
Article number566
JournalSensors (Switzerland)
Volume17
Issue number3
DOIs
Publication statusPublished - 2017 Mar 10

All Science Journal Classification (ASJC) codes

  • Analytical Chemistry
  • Biochemistry
  • Atomic and Molecular Physics, and Optics
  • Instrumentation
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'Terrestrial water storage in African Hydrological regimes derived from GRACE mission data: Intercomparison of spherical harmonics, mass concentration, and Scalar Slepian methods'. Together they form a unique fingerprint.

Cite this