Abstract. Data scarcity is the biggest problem for scientific research
related to hydrology and climate studies in the Great Himalayas region.
High-quality precipitation data are difficult to obtain due to a sparse
network, cold climate and high heterogeneity in topography. In this paper, we
examine four datasets in northern India of the Western Himalayas:
interpolated gridded data based on gauge observations (IMD,
1∘×1∘, and APHRODITE,
0.25∘×0.25∘), reanalysis data (ERA-Interim,
0.75∘×0.75∘) and high-resolution simulation by a
regional climate model (WRF, 0.15∘×0.15∘). The four
datasets show a similar spatial pattern and temporal variation during the
period 1981–2007, though the absolute values vary significantly
(497–819 mm year−1). The differences are
particularly large in July and August at the windward slopes and
high-elevation areas. Overall, the datasets show that the summer is getting
wetter and the winter is getting drier, though most of the trends in monthly
precipitation are not significant. Trend analysis of summer and winter
precipitation at every grids confirms the changes. Wetter summers will result
in more and bigger floods in the downstream areas. Warmer and drier winters
will result in less glacier accumulation. All the datasets show
consistency in the period 1981–2007 and can give a spatial overview of the
precipitation in the region. Comparing with the Bhuntar gauge data, the WRF
dataset gives the best estimates of extreme precipitation. To conclude, we
recommend the APHRODITE dataset and the WRF dataset for hydrological studies
for their improved spatial variation which match the scale of hydrological
processes as well as accuracy in extreme precipitation for flood simulation.
Precipitation pattern in the Western Himalayas revealed by four datasets
