Journal cover Journal topic
Hydrology and Earth System Sciences An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

IF value: 5.153
IF 5-year value: 5.460
IF 5-year
CiteScore value: 7.8
SNIP value: 1.623
IPP value: 4.91
SJR value: 2.092
Scimago H <br class='widget-line-break'>index value: 123
Scimago H
h5-index value: 65
Volume 17, issue 5
Hydrol. Earth Syst. Sci., 17, 1715–1732, 2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
Hydrol. Earth Syst. Sci., 17, 1715–1732, 2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.

Research article 02 May 2013

Research article | 02 May 2013

Hydrological drought across the world: impact of climate and physical catchment structure

H. A. J. Van Lanen1, N. Wanders1,2, L. M. Tallaksen3, and A. F. Van Loon1 H. A. J. Van Lanen et al.
  • 1Hydrology and Quantitative Water Management Group, Centre for Water and Climate, Wageningen University, Wageningen, the Netherlands
  • 2Department of Physical Geography, Faculty of Geosciences, Utrecht University, Utrecht, the Netherlands
  • 3Department of Geosciences, University of Oslo, Oslo, Norway

Abstract. Large-scale hydrological drought studies have demonstrated spatial and temporal patterns in observed trends, and considerable difference exists among global hydrological models in their ability to reproduce these patterns. In this study a controlled modeling experiment has been set up to systematically explore the role of climate and physical catchment structure (soils and groundwater systems) to better understand underlying drought-generating mechanisms. Daily climate data (1958–2001) of 1495 grid cells across the world were selected that represent Köppen–Geiger major climate types. These data were fed into a conceptual hydrological model. Nine realizations of physical catchment structure were defined for each grid cell, i.e., three soils with different soil moisture supply capacity and three groundwater systems (quickly, intermediately and slowly responding). Hydrological drought characteristics (number, duration and standardized deficit volume) were identified from time series of daily discharge. Summary statistics showed that the equatorial and temperate climate types (A- and C-climates) had about twice as many drought events as the arid and polar types (B- and E-climates), and the durations of more extreme droughts were about half the length. Selected soils under permanent grassland were found to have a minor effect on hydrological drought characteristics, whereas groundwater systems had major impact. Groundwater systems strongly controlled the hydrological drought characteristics of all climate types, but particularly those of the wetter A-, C- and D-climates because of higher recharge. The median number of droughts for quickly responding groundwater systems was about three times higher than for slowly responding systems. Groundwater systems substantially affected the duration, particularly of the more extreme drought events. Bivariate probability distributions of drought duration and standardized deficit for combinations of Köppen–Geiger climate, soil and groundwater system showed that the responsiveness of the groundwater system is as important as climate for hydrological drought development. This urges for an improvement of subsurface modules in global hydrological models to be more useful for water resources assessments. A foreseen higher spatial resolution in large-scale models would enable a better hydrogeological parameterization and thus inclusion of lateral flow.

Publications Copernicus