TY - JOUR

T1 - What can we learn from comparing glacio-hydrological models?

AU - Stoll, Elena

AU - Hanzer, Florian

AU - Oesterle, Felix

AU - Nemec, Johanna

AU - Schöber, Johannes

AU - Huttenlau, Matthias

AU - Förster, Kristian

N1 - Funding Information: This work was carried out as part of the project W01 MUSICALS II-Multiscale Snow/Ice Melt Discharge Simulation for Alpine Reservoirs project at alpS-Centre for Climate Change Adaptation in Innsbruck, Austria. The K1-Centre alpS was funded through the Federal Ministry of Transport, Innovation and Technology (BMVIT), the Federal Ministry of Science, Research and Economy (BMWFW), and the Austrian federal states of Tyrol and Vorarlberg within the scope of COMET-Competence Centers for Excellent Technologies. The COMET programme is managed by the Austrian Research Promotion Agency (FFG). We want to thank TirolerWasserkraft AG (TIWAG) for the collaboration and for co-funding the project. For the data support we thank the TIWAG, and the HD-Hydrographic Service of Tyrol, the ACINN-Department of Atmospheric and Cryospheric Sciences of the University Innsbruck. We gratefully acknowledge Ben Marzeion for providing the GEM model. Moritz Zimmermann, Stefan Berlin, and Benjamin Winter helped with GIS. Finally, we thank all reviewers for their helpful comments.

PY - 2020/9/14

Y1 - 2020/9/14

N2 - Glacio-hydrological models combine both glacier and catchment hydrology modeling and are used to assess the hydrological response of high-mountain glacierized catchments to climate change. To capture the uncertainties from these model combinations, it is essential to compare the outcomes of several model entities forced with the same climate projections. For the first time, we compare the results of two completely independent glacio-hydrological models: (i) HQsim-GEM and (ii) AMUNDSEN. In contrast to prevailing studies, we use distinct glacier models and glacier initialization times. At first glance, the results achieved for future glacier states and hydrological characteristics in the Rofenache catchment in ötztal Alps (Austria) appear to be similar and consistent, but a closer look reveals clear differences. What can be learned from this study is that low-complexity models can achieve higher accuracy in the calibration period. This is advantageous especially when data availability is weak, and priority is given to efficient computation time. Furthermore, the time and method of glacier initialization play an important role due to different data requirements. In essence, it is not possible to make conclusions about the model performance outside of the calibration period or more specifically in the future. Hence, similar to climate modeling, we suggest considering different modeling approaches when assessing future catchment discharge or glacier evolution. Especially when transferring the results to stakeholders, it is vital to transparently communicate the bandwidth of future states that come with all model results.

AB - Glacio-hydrological models combine both glacier and catchment hydrology modeling and are used to assess the hydrological response of high-mountain glacierized catchments to climate change. To capture the uncertainties from these model combinations, it is essential to compare the outcomes of several model entities forced with the same climate projections. For the first time, we compare the results of two completely independent glacio-hydrological models: (i) HQsim-GEM and (ii) AMUNDSEN. In contrast to prevailing studies, we use distinct glacier models and glacier initialization times. At first glance, the results achieved for future glacier states and hydrological characteristics in the Rofenache catchment in ötztal Alps (Austria) appear to be similar and consistent, but a closer look reveals clear differences. What can be learned from this study is that low-complexity models can achieve higher accuracy in the calibration period. This is advantageous especially when data availability is weak, and priority is given to efficient computation time. Furthermore, the time and method of glacier initialization play an important role due to different data requirements. In essence, it is not possible to make conclusions about the model performance outside of the calibration period or more specifically in the future. Hence, similar to climate modeling, we suggest considering different modeling approaches when assessing future catchment discharge or glacier evolution. Especially when transferring the results to stakeholders, it is vital to transparently communicate the bandwidth of future states that come with all model results.

KW - Catchment hydrology

KW - Climate change

KW - Glacier retreat

KW - Glacierized catchments

KW - Glacio-hydrological models

KW - Model comparison

KW - Modeling future runoff

KW - Snow and ice melt

UR - http://www.scopus.com/inward/record.url?scp=85094138521&partnerID=8YFLogxK

U2 - 10.3390/atmos11090981

DO - 10.3390/atmos11090981

M3 - Article

AN - SCOPUS:85094138521

VL - 11

JO - Atmosphere

JF - Atmosphere

SN - 2073-4433

IS - 9

M1 - 981

ER -