The representation of extreme precipitation at small spatio-temporal scales is of major importance in urban hydrology. The present study compares point and radar observations to reanalyse climate model output data for a period of 14 years where there is full spatial and temporal overlap between datasets. The datasets are compared with respect to seasonality of occurrence, intensity levels and spatial structure of the extreme events. All datasets have similar seasonal distributions and comparable intensity levels. There are, however, clear differences in the spatial correlation structure of the extremes. Seemingly, the radar data is the best representation of a “real” spatial structure for extreme precipitation, even though challenges appear in data when moving far from the physical radar. The spatial correlation in point observations is a valid representation of the spatial structure of extreme precipitation. The convective-permitting climate model seems to represent the spatial structure of extreme precipitation much more realistically, compared to the coarser convective parameterized model. However, there is still room for improvement of the convective-permitting climate model for the shortest rainfall durations and smallest spatial scales in comparison with point and radar data.
|Tidsskrift||Journal of Hydrology|
|Status||Udgivet - jul. 2022|
Bibliografisk noteFunding Information:
Emma D. Thomassen received funding from the Danish State through the Danish Climate Atlas. All other researchers were supported by the Foundation for Development of Technology in the Danish Water Sector, Project: VÆRDI, Grant/Award Number: 57.2019. The POINT observational dataset is a product of The Water Pollution Committee of The Society of Danish Engineers made freely available for research purposes. Access to data is governed by the Danish Meteorological Institute, and they should be contacted for enquiries regarding data access. The RADAR dataset is an adjusted versions of the Danish national radar network, operated by the Danish Meteorological Institute. Aalborg University, and specifically S.L. Thorndahl, should be contacted regarding data inquires. The HCLIM simulations were performed by the NorCP (Nordic Convection Permitting Climate Projections) project group, a collaboration between the Danish Meteorological Institute (DMI), the Finnish Meteorological Institute (FMI), the Norwegian Meteorological Institute (MET Norway), and the Swedish Meteorological and Hydrological Institute (SMHI).
© 2022 The Author(s)
- Convective permitting model
- e-folding distance
- Intensity-duration frequency curves
- Regional climate model
- Spatial correlation
- Weather radar