International Workshop on Hyper-resolution Global Hydrological Modelling

Toward global-scale models that are relevant at local scales!

On February 13/14 an international workshop was organized at Utrecht University, bringing together hydrologists from around the world that are involved in large-scale high- to hyper-resoluytion modelling of terrestrial hydrology. A succesfull workshop lead to the foundation of the HYperHydro network with three working groups:

  • WG1: Setting up a testbed for comparing different large-scale models at different resolutions.
  • WG2: Around computational challenges, including parallel computing and model component coupling.
  • WG3: With the goal to think about delivering the information needed to achieve hyper-resolution (< 1 km) globally: parameter sets, model concepts and forcing.

A splinter meeting will be organized at EGU 2014 in Vienna to further the network activities. You are welcome to join any of the groups by sending email to Marc Bierkens.

The workshop program and pdfs of the presentations can be found here!

Yoshihide Wada obtains his PhD degree with distinction!

On Friday November 8 Yoshihide Wada defended his PhD thesis entitled “Human and climate impacts on global water resources“.

He obtained his degree Cum Laude (top 3-5%) due to the exceptional quality of his work. The PhD evaluation committee consisted of Prof. Taikan Oki (Tokyo University), Dr. Dieter Gerten (PIK Potsdam), Prof. Arjen Hoekstra (University of Twente), Prof. Stefan Uhlenbrook (UNESCO-IHE and Delf University of Technology and Prof. Lex Bouwman (PBL and Utrecht University). Independent assessment reports were provided by dr. Peter Gleick (Pacific Institute) and Prof. Pavel Kabat (IIASA and Wageningen University).

His PhD, consisting of 14 chapters (12 of which are published or submitted papers), can be downloaded from:

Over past decades, terrestrial water fluxes have been affected by humans at an unprecedented scale and the fingerprints that humans have left on Earth’s water resources are turning up in a diverse range of records. In this thesis, a state-of-the-art global hydrological model (GHM) and global water demand model were developed and eventually coupled to quantify and distinguish human and climate impacts on surface freshwater and groundwater resources. The thesis is composed of three major parts: Part 1. Human and climate impacts on surface freshwater resources; Part 2. Global assessment of groundwater resources; Part 3. Integrated modeling and indicators of global water resources.The thesis first explores the human and climate impacts on seasonal surface freshwater resources by forcing the global hydrological model PCR‐GLOBWB with daily meteorological fields and by calculating global monthly water demands with the effects of socio-economic and land use change. Increased water demand was found to be a decisive factor for heightened water stress in various regions, while climate variability is often a main determinant of extreme events. Over Europe, North America and Asia, severe hydrological drought conditions are driven by increasing consumptive water use rather than to be merely induced by climate variability; the magnitude of droughts intensified by 10-500%.Next, the thesis assesses global groundwater resources by estimating groundwater recharge and abstraction. Global groundwater depletion was found to triple in size over the last 50 years, and contributes ~20% to irrigation water supply. Groundwater stress was then assessed using newly developed indicators considering groundwater contribution to environment. The global groundwater footprint was found to be 3.5 times the actual area of aquifers driven by a few heavily overexploited aquifers. The aquifer stress indicator revealed that ~8% of transboundary aquifers are currently stressed due to human overexploitation. Importantly, groundwater depletion was found to be an important contributor to sea-level rise and is likely to dominate over those of other terrestrial water sources. The contribution of groundwater depletion to sea-level increased by more than ten-fold over 1900-2000, and is projected to increase further by 2050.In the final part of this thesis, an improved modeling framework that dynamically simulates daily water use per source per sector was developed. Human impacts on terrestrial water storage signals were evident in the validation with GRACE satellite observation, altering the seasonal and inter-annual variability over heavily regulated and intense irrigated basins. The newly developed model together with other six state-of-the-art GHMs was applied to simulate future irrigation water demand using the latest CMIP5 climate projections. The increase in irrigation demand varies substantially depending on the degree of global warming and associated regional precipitation changes. GHM dominates the uncertainty throughout the century, but GCM uncertainty substantially increases from the mid-century. To comprehensively assess global water resources, an improved approach was introduced. The Green Water Stress Index is capable of reproducing varying degrees of green water stress conditions, reflecting a multi-decadal climate variability. The Blue Water Sustainability Index revealed an increasing trend of water consumed from nonsustainable surface water and groundwater resources (~30%) worldwide.


New publication on Himalayan glaciers in Nature Geoscience

In a new publication in Nature Geoscience Walter Immerzeel and Marc Bierkens project an increase in runoff from Himalayan catchmants during the 21st century, despite a decline in glacier size.  See why and how on:

or read the Utrecht University press release:

reference: W.W. Immerzeel, F. Pellicciotti en M.F.P. Bierkens, ‘Rising river flows throughout the twenty-first century in two Himalayan glacierized watersheds’, Nature Geoscience, doi:10.1038/ngeo1896, 2013.

Fieldwork at Lirung Glacier Nepal

Walter Immerzeel, Steven de Jong and Marc Bierkens have conducted field work at Lirung Glacier in Langtang National Park, Nepal (4000-5000 m amsl).


Marc, Walter and Steven at 5007 m altitude

Using an unmanned aerial vehicle (UAV) they made overlapping photo’s of the glacier with the goal to construct a digital elevation model (4-10 cm resolution). In October, after the ablation season, Steven de Jong and a student will return for another flight. From the differences between the constructed elevation models they hope to estimate the mass-wasting of the glacier as well as the ice velocity based on advanced feature tracking.

In the same area, the scientists also conduct observations of precipation at various altitude to determine precipitation lapse rates.

The glacier velocities, mass-loss rates and precipiation lapse rates will be used to improve glacio-hydrological models of the region.

See a pdf with a short presentation of the fieldwork and some preliminary results

Nature publication: global groundwater footprint

Our group co-authored a publication in nature about global sustainable and non-sustainable groundwater use:

The nature news feature:

The paper:

Also check out the podcast with lead author Tom Gleeson of McGill University


See us at EGU 2012!

The following papers will be presented at the next EGU meeting in Vienna, from Monday 23th of April to Friday 27th of April

Oral Programme Mon, 23 Apr, 15:30–17:00 / Room 38 15:30–15:45
EGU2012-2055 Non-sustainable groundwater sustaining irrigation – a global assessment Y. Wada, L.P.H. van Beek, and M.F.P. Bierkens

Oral Programme Mon, 23 Apr, 13:30–17:00 Room 33 16:00–16:15
EGU2012-13081 Patterns and Pathways of Evolving Catchment Response in a Medium-Sized Mediterranean Catchment on a Millennium Scale
L.P.H. van Beek and M.F.P. Bierkens

Oral Programme Wed, 25 Apr, 13:30–17:00 Room 36 15:45–16:00
EGU2012-5338 Using high-resolution soil moisture modelling to assess the uncertainty of microwave remotely sensed soil moisture products at the correct spatial and temporal support
N. Wanders, D. Karssenberg, M.F.P. Bierkens, J.C. Van Dam, and S.M. De Jong

Oral Programme Thu, 26 Apr, 08:30–10:00 Room 36 09:45–10:00
EGU2012-6629 Can we monitor groundwater head variation from space? Coupling ERS spaceborne microwave observations to groundwater dynamics
E.H. Sutanudjaja, S.M. de Jong, F.C. van Geer, and M.F.P. Bierkens

Oral Programme Thu, 26 Apr, 15:30–17:00 Room 2 16:30–16:45
EGU2012-2765 Automated geomorphological mapping using Multiple Point Geostatistics E. Vannametee, L.V. Babel, D. Karssenberg, J. Schuur, M.R. Hendriks, and M.F.P. Bierkens

Oral Programme Fri, 27 Apr, 08:30–12:00 Room 3 09:30–09:45
EGU2012-13141 (invited) Modelling Landscape Dynamics in a Highland Mediterranean Catchment: Establishing the impact of Climate Variation and Human Activity
L.P.H. van Beek, H. Feiken, T.W.J. van Asch, and M.F.P. Bierkens

Poster Programme Attendance Mon, 23 Apr, 17:30–19:00 Hall A A165
EGU2012-2008 Value assessment of a global hydrological forecasting system
N. Candogan Yossef, H. Winsemius, L.P.H. van Beek, E. van Beek, and M.F.P. Bierkens

Poster Programme Attendance Tue, 24 Apr, 17:30–19:00 Hall Z Z96
EGU2012-4320 Early-warning signals (potentially) reduce uncertainty in forecasted timing of critical shifts
D. Karssenberg and M.F.P. Bierkens

Poster Programme Attendance Tue, 24 Apr, 17:30–19:00 Hall A A199
EGU2012-1988 The effects of groundwater abstraction on low flows
I.E.M. de Graaf, L.P.H. van Beek, Y. Wada, and M.F.P. Bierkens

Poster Programme Attendance Wed, 25 Apr, 17:30–19:00 Hall A A169
EGU2012-6138 Human water consumption intensifies hydrological drought worldwide
M. F. P. Bierkens, Y. Wada, D. Wisser, N. Wanders, and L. P. H. Van Beek



Dear Visitor,

Welcome to the pages of the Earth Surface Hydrology group at Utrecht University. Our group was established in 2002. We are part of the Department of Physical Geography , one of the four departments of the Faculty of Geosciences.

Earth Surface Hydrology is concerned with the study of hydrological processes near and on the earth surface. It focuses on the flow of water, nutrients and energy between the earth surface and the subsoil and between the earth surface and the atmosphere. It aims to quantify how rainfall is portioned into infiltration, evaporation and runoff, and how nutrients in the soil and the earth surface are distributed through the landscape through surface runoff and groundwater flow.

Our research focuses on three major themes: 1) Large-scale hydrology, including the global hydrological model PCR-GLOBWB (link to global hydrology site); 2) Ecohydrology and eco-geomorphology; 3) Geocomputation.  Check out our Research pages for more information.

We are responsible for two MSc programs: Earth Surface and Water, in particular the track Hydrology and a new program called Water Science and Management. Look under Education to find out more about courses taught by our group.

Thank you for your interest,


Marc Bierkens
Chair in Earth Surface Hydrology