What can we learn from comparing glacio-hydrological models?

authored by

Elena Stoll, Florian Hanzer, Felix Oesterle, Johanna Nemec, Johannes Schöber, Matthias Huttenlau, Kristian Förster

Abstract

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.

Organisation(s)

Institute of Hydrology and Water Resources Management

External Organisation(s)

University of Innsbruck
University of Graz
University of Natural Resources and Applied Life Sciences (BOKU)
Environmental Earth Observation IT GmbH (ENVEO IT)
Tiroler Wasserkraft AG (TIWAG)
ILF Consulting Engineers

Type

Article

Journal

Atmosphere

Volume

11

ISSN

2073-4433

Publication date

14.09.2020

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Environmental Science (miscellaneous)

Sustainable Development Goals

SDG 13 - Climate Action

Electronic version(s)

https://doi.org/10.3390/atmos11090981 (Access: Open)