Latest version: V2.1 (released November 20, 2017)
Multi-Source Weighted-Ensemble Precipitation (MSWEP) is a new fully global historic precipitation dataset (1979–2016) with a 3-hourly temporal and 0.1° spatial resolution.
Why use MSWEP?
- MSWEP takes advantage of the complementary strengths of gauge-, satellite-, and reanalysis-based data to provide reliable precipitation estimates over the entire globe (Beck et al., 2017a).
- In a comprehensive global-scale evaluation of 22 precipitation datasets, MSWEP performed best overall (Beck et al., 2017b).
- Truly global coverage (including ocean areas) at 3-hourly 0.1° resolution (other satellite-based datasets, such as TMPA 3B42, are limited to latitudes <50/60°).
- Consistent precipitation record from 1979 until the near present, enabling trend and drought assessments.
- Daily (rather than monthly) gauge corrections.
- When applying the daily gauge corrections, MSWEP accounts for differences in gauge reporting times.
Validation
MSWEP has been validated at global scale using observations from ~70,000 gauges and hydrological modeling for ~9000 catchments (Beck et al., 2017b). The dataset was found to perform better overall in terms of temporal variability, trend, number of dry days, peak magnitude, etc., compared to other widely used precipitation datasets (e.g., CPC Unified, CHIRPS, CMORPH-CRT, GPCP-1DD, GSMaP, PERSIANN-CCS, PERSIANN-CDR, WFDEI-CRU, and TMPA 3B42). See the following open-access paper for more information:
- Beck, H. E., N. Vergopolan, M. Pan, V. Levizzani, A.I.J.M. van Dijk, G.P. Weedon, L. Brocca, F. Pappenberger, G.J. Huffman, and E.F. Wood: Global-scale evaluation of 22 precipitation datasets using gauge observations and hydrological modeling, Hydrology and Earth System Sciences, 21(12), 6201–6217, 2017b.

For each catchment, the precipitation dataset that provided the best streamflow simulations. Adapted from Beck et al. (2017b).
Methodology
MSWEP optimally merges a wide range of gauge, satellite, and reanalysis data to provide reliable precipitation estimates over the entire globe. See the following open-access paper for a detailed description of the MSWEP V1.1 methodology:
- Beck, H.E., A.I.J.M. van Dijk, V. Levizzani, J. Schellekens, D.G. Miralles, B. Martens, A. de Roo: MSWEP: 3-hourly 0.25° global gridded precipitation (1979–2015) by merging gauge, satellite, and reanalysis data, Hydrology and Earth System Sciences, 21(1), 589–615, 2017a.
The methodology used to produce the latest version (V2) is described in the most recent MSWEP technical documentation. The paper about V2 is still in preparation. The most important changes in V2 compared to V1 include: (i) the use of cumulative distribution function matching to correct the spurious drizzle and attenuated peaks evident in V1; (ii) increasing the spatial resolution from 0.25° to 0.1°; (iii) the inclusion of ocean areas; (iv) the addition of infrared-based precipitation estimates for the pre-TRMM era to supplement the reanalysis and gauge data; (v) the addition of 0.1° daily interpolated gauge data to replace the coarse (0.5°) CPC Unified dataset; (vi) the use of a daily gauge correction scheme that accounts for differences in daily gauge reporting times, to minimize timing mismatches when applying the daily gauge corrections; and (vii) extension of the data record to 2016.
Data access
Please fill in the web form to obtain access to MSWEP. We will get back to you in about one or two days with details on how to access the data. For questions, please contact Hylke Beck. The latest technical documentation, including the version history and examples on how to read the data with MATLAB and Python, is available here.
Acknowledgements
MSWEP is being developed by Hylke Beck (Princeton University, Princeton, NJ, USA). The precipitation dataset developers are gratefully acknowledged for producing and making available their datasets. The work was supported through IPA support from the U.S. Army Corps of Engineers’ International Center for Integrated Water Resources Management (ICIWaRM), under the auspices of UNESCO. By using MSWEP in any publication you agree to cite Beck et al. (2017a).