Assessing Gauge Undercatch Correction in Arctic Basins in Light of GRACE Observations. Issue 20 (21st October 2019)

• Record Type: Journal Article
• Authors: Behrangi, Ali; Singh, Alka; Song, Yang; Panahi, Milad
• Is Part Of: Geophysical research letters. Volume 46:Issue 20(2019)
• Page Start: 11358
• Page End: 11366
• Publication Date: 2019-10-21
• Subjects: precipitation -- high latitude -- gauge undercatch -- GRACE; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1029/2019GL084221
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Precipitation measurements at gauges are often considered as reference truth for evaluation of satellite precipitation products. However, gauges may contain large errors. A major source of gauge‐measurement error is snowfall undercatch in high latitudes. We show that the two popular correction factors (CFs) used in the Global Precipitation Climatology Centre monitoring and the Global Precipitation Climatology Project products are different by more than 50%. The CFs can be as large as 3; thus, the choice of CF introduces large uncertainties. Here, in light of observation of storage change from the Gravity Recovery and Climate Experiment (GRACE) and by using the mass conservation principle, we assess the two popular CFs over six Arctic basins. By investigating monthly time series and multiyear precipitation rates over the studied basins using GRACE‐based analysis, the CF based on Fuchs dynamic correction model used in Global Precipitation Climatology Centre monitoring is preferred. Key Points: Gauge undercatch correction is necessary to reduce errors in gauge‐based precipitation products in cold months More than 50% difference can exist among gauge undercatch correction methods used in the popular GPCC and GPCP products GRACE mass change observations provide a unique way to assess gauge undercatch correction methods