Climate-dependent propagation of precipitation uncertainty into the water cycle
<p>Precipitation is a crucial variable for hydro-meteorological applications. Unfortunately, rain gauge measurements are sparse and unevenly distributed, which substantially hampers the use of in situ precipitation data in many regions of the world. The increasing availability of high-resoluti...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2020-07-01
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| Series: | Hydrology and Earth System Sciences |
| Online Access: | https://hess.copernicus.org/articles/24/3725/2020/hess-24-3725-2020.pdf |
| Summary: | <p>Precipitation is a crucial variable for hydro-meteorological
applications. Unfortunately, rain gauge measurements are sparse and unevenly
distributed, which substantially hampers the use of in situ precipitation
data in many regions of the world. The increasing availability of
high-resolution gridded precipitation products presents a valuable
alternative, especially over poorly gauged regions. This study examines the
usefulness of current state-of-the-art precipitation data sets in
hydrological modeling. For this purpose, we force a conceptual hydrological
model with multiple precipitation data sets in <span class="inline-formula"><i>></i>200</span> European
catchments to obtain runoff and evapotranspiration. We consider a wide range
of precipitation products, which are generated via (1) the interpolation of
gauge measurements (E-OBS and Global Precipitation Climatology Centre (GPCC) V.2018), (2) data assimilation into
reanalysis models (ERA-Interim, ERA5, and Climate Forecast System Reanalysis – CFSR), and (3) a combination of
multiple sources (Multi-Source Weighted-Ensemble Precipitation; MSWEP V2). Evaluation is done at the daily and monthly
timescales during the period of 1984–2007. We find that simulated runoff
values are highly dependent on the accuracy of precipitation inputs; in
contrast, simulated evapotranspiration is generally much less influenced in
our comparatively wet study region. We also find that the impact of
precipitation uncertainty on simulated runoff increases towards wetter
regions, while the opposite is observed in the case of evapotranspiration.
Finally, we perform an indirect performance evaluation of the precipitation
data sets by comparing the runoff simulations with streamflow observations.
Thereby, E-OBS yields the particularly strong agreement, while ERA5, GPCC V.2018, and MSWEP V2 show good performances. We further reveal
climate-dependent performance variations of the considered data sets, which
can be used to guide their future development. The overall best agreement is
achieved when using an ensemble mean generated from all the individual
products. In summary, our findings highlight a climate-dependent propagation
of precipitation uncertainty through the water cycle; while runoff is
strongly impacted in comparatively wet regions, such as central Europe, there
are increasing implications for evapotranspiration in drier regions.</p> |
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| ISSN: | 1027-5606 1607-7938 |