Comparing projections of future changes in runoff from hydrological and biome models in ISI-MIP

  • Future changes in runoff can have important implications for water resources and flooding. In this study, runoff projections from ISI-MIP (Inter-sectoral Impact Model Intercomparison Project) simulations forced with HadGEM2-ES bias-corrected climate data under the Representative Concentration Pathway 8.5 have been analysed for differences between impact models. Projections of change from a baseline period (1981–2010) to the future (2070–2099) from 12 impacts models which contributed to the hydrological and biomes sectors of ISI-MIP were studied. The biome models differed from the hydrological models by the inclusion of CO2 impacts and most also included a dynamic vegetation distribution. The biome and hydrological models agreed on the sign of runoff change for most regions of the world. However, in West Africa, the hydrological models projected drying, and the biome models a moistening. The biome models tended to produce larger increases and smaller decreases in regionally averaged runoff than the hydrological models, although there is large inter-model spread. The timing of runoff change was similar, but there were differences in magnitude, particularly at peak runoff. The impact of vegetation distribution change was much smaller than the projected change over time, while elevated CO2 had an effect as large as the magnitude of change over time projected by some models in some regions. The effect of CO2 on runoff was not consistent across the models, with two models showing increases and two decreases. There was also more spread in projections from the runs with elevated CO2 than with constant CO2. The biome models which gave increased runoff from elevated CO2 were also those which differed most from the hydrological models. Spatially, regions with most difference between model types tended to be projected to have most effect from elevated CO2, and seasonal differences were also similar, so elevated CO2 can partly explain the differences between hydrological and biome model runoff change projections. Therefore, this shows that a range of impact models should be considered to give the full range of uncertainty in impacts studies.

Download full text files

Export metadata

Additional Services

Share in Twitter Search Google Scholar
Author:Jemma C. S. Davie, Peter D. Falloon, Ron Kahana, Rutger Dankers, Richard Betts, Felix Theodor Portmann, Dominik Wisser, Douglas B. Clark, Akihiko Itoh, Yoshimitsu Masaki, Kazuya Nishina, Balazs M. Fekete, Zachary Tessler, Yoshihide WadaORCiDGND, Xingcai Liu, Qiuhong TangORCiD, Stefan Hagemann, Tobias StackeORCiD, Ryan Pavlick, Sibyll Schaphoff, Simon N. GoslingORCiDGND, Wietse Franssen, Nigel Arnell
Parent Title (English):Earth System Dynamics
Publisher:Copernicus Publications
Place of publication:Göttingen
Document Type:Article
Date of Publication (online):2016/12/22
Date of first Publication:2013/10/10
Publishing Institution:Universitätsbibliothek Johann Christian Senckenberg
Release Date:2016/12/22
Page Number:16
First Page:359
Last Page:374
Institutes:Geowissenschaften / Geographie / Geowissenschaften
Dewey Decimal Classification:5 Naturwissenschaften und Mathematik / 55 Geowissenschaften, Geologie / 550 Geowissenschaften
Licence (German):License LogoCreative Commons - Namensnennung 3.0