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| Titel |
Hourly Comparison of GPM-IMERG-Final-Run and IMERG-Real-Time (V-03) over a Dense Surface Network in Northeastern Austria |
| VerfasserIn |
Ehsan Sharifi, Reinhold Steinacker, Bahram Saghafian |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250138822
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| Publikation (Nr.) |
 EGU/EGU2017-1949.pdf |
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| Zusammenfassung |
| Accurate quantitative daily precipitation estimation is key to meteorological and hydrological
applications in hazards forecast and management. In-situ observations over mountainous
areas are mostly limited, however, currently available satellite precipitation products can
potentially provide the precipitation estimation needed for meteorological and hydrological
applications. Over the years, blended methods that use multi-satellites and multi-sensors have
been developed for estimating of global precipitation. One of the latest satellite
precipitation products is GPM-IMERG (Global Precipitation Measurement with
30-minute temporal and 0.1-degree spatial resolutions) which consists of three products:
Final-Run (aimed for research), Real-Time early run, and Real-Time late run. The
Integrated Multisatellite Retrievals for GPM (IMERG) products built upon the success
of TRMM’s Multisatellite Precipitation Analysis (TMPA) products continue to
make improvements in spatial and temporal resolutions and snowfall estimates.
Recently, researchers who evaluated IMERG-Final-Run V-03 and other precipitation
products indicated better performance for IMERG-Final-Run against other similar
products. In this study two GPM-IMERG products, namely final run and real time-late
run, were evaluated against a dense synoptic stations network (62 stations) over
Northeastern Austria for mid-March 2015 to end of January 2016 period at hourly
time-scale. Both products were examined against the reference data (stations) in
capturing the occurrence of precipitation and statistical characteristics of precipitation
intensity. Both satellite precipitation products underestimated precipitation events of 0.1
mm/hr to 0.4 mm/hr in intensity. For precipitations 0.4 mm/hr and greater, the trend
was reversed and both satellite products overestimated than station recorded data.
IMERG-RT outperformed IMERG-FR for precipitation intensity in the range of
0.1 mm/hr to 0.4 mm/hr while in the range of 1.1 to 1.8 mm/hr, IMERG-FR was
closer to the ground data. The results also showed that the cumulative distribution
function (CDF) of both IMERG products’ were well above that of the stations’
precipitation. However, at 94% frequency level, ground data was less than 2.5 mm/hr which
corresponded to 88% frequency level in IMERG-Cal and IMERG-RT. Below 2.5
mm/hr, IMERG-RT was slightly lower than the IMERG-FR whereas IMERG-RT
was above IMERG-FR at higher precipitation levels. The result showed an overall
overestimation of the precipitation frequency by both IMERG-FR and IMERG-RT. |
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