Journal cover Journal topic
Hydrology and Earth System Sciences An interactive open-access journal of the European Geosciences Union
https://doi.org/10.5194/hess-2018-248
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
Research article
14 May 2018
Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Hydrology and Earth System Sciences (HESS).
An assessment of trends and potential future changes in groundwater-baseflow drought based on catchment response times
Jost Hellwig and Kerstin Stahl Faculty of Environment and Natural Resources, University of Freiburg, 79098 Freiburg, Germany
Abstract. Drought is an important natural hazard with large impacts on society. Changes in drought characteristics have been studied for different parts of the hydrological cycle, but insights in changes of groundwater resources are obscured due to the lack of long-term observations and large heterogeneity of hydrogeological conditions. Moreover, predicted future changes in precipitation are uncertain and have a lagged effect on streamflow and groundwater. We investigated past changes and potential future changes in catchment baseflow as a reflexion of groundwater drought for 338 headwater catchments across Germany based on catchments' characteristic response times. First, baseflow dynamics as a proxy of groundwater storage and outflow on catchment scale were derived from streamflow records and related to precipitation input. Second, past trends in baseflow minima were calculated and attributed to climate and catchment controls. Last, response times and the timing of yearly baseflow minima were combined into scenario-neutral estimates of the sensitivity to future precipitation changes. Baseflow response times of the studied headwaters are heterogenous across Germany, ranging from few months to several years, and depend significantly on hydrogeological conditions. Few significant trends were found in past baseflow minima and trends are highly dependent on the period of analysis. Based on the assumption of a typical regional scenario of increasing winter precipitation and decreasing summer precipitation, increases in hydrological drought hazard or no changes are projected for most parts of Germany. Catchments with longer response times can buffer interannual precipitation shifts whereas catchments with fractured rocks are sensitive to summer precipitation decreases. These results urge for a surface- and groundwater management based on local groundwater response to precipitation and help to assess impacts of climate change on overall water supply.
Citation: Hellwig, J. and Stahl, K.: An assessment of trends and potential future changes in groundwater-baseflow drought based on catchment response times, Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2018-248, in review, 2018.
Jost Hellwig and Kerstin Stahl
Jost Hellwig and Kerstin Stahl
Jost Hellwig and Kerstin Stahl

Viewed

Total article views: 139 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
94 32 13 139 1 3

Views and downloads (calculated since 14 May 2018)

Cumulative views and downloads (calculated since 14 May 2018)

Viewed (geographical distribution)

Total article views: 139 (including HTML, PDF, and XML)

Thereof 138 with geography defined and 1 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 20 May 2018
Publications Copernicus
Download
Short summary
Due to the lack of long-term observations insights in changes of groundwater resources are obscured. In this paper we assess past and potential future changes on groundwater drought in headwater catchments using a baseflow approach. There are few past trends which are highly dependent on the period of analysis. Catchments with short response times are found to have a higher sensitivity to projected seasonal precipitation shifts urging for a local management based on response times.
Due to the lack of long-term observations insights in changes of groundwater resources are...
Share