Sensitivity of projected climate impacts to climate model weighting: multi-sector analysis in eastern Africa

Kolusu, Seshagiri Rao, Siderius, Christian, Todd, Martin C., Bhave, Ajay, Conway, Declan ORCID: 0000-0002-4590-6733, James, Rachel, Washington, Richard, Geressu, Robel, Harou, Julien J. and Kashaigili, Japhet J. (2021) Sensitivity of projected climate impacts to climate model weighting: multi-sector analysis in eastern Africa. Climatic Change, 164 (3-4). ISSN 0165-0009

Text (Kolusu2021_Article_SensitivityOfProjectedClimateI (1)) - Published Version Available under License Creative Commons Attribution. Download (1MB)

• Author
• Author
• Author

Abstract

Uncertainty in long-term projections of future climate can be substantial and presents a major challenge to climate change adaptation planning. This is especially so for projections of future precipitation in most tropical regions, at the spatial scale of many adaptation decisions in water-related sectors. Attempts have been made to constrain the uncertainty in climate projections, based on the recognised premise that not all of the climate models openly available perform equally well. However, there is no agreed ‘good practice’ on how to weight climate models. Nor is it clear to what extent model weighting can constrain uncertainty in decision-relevant climate quantities. We address this challenge, for climate projection information relevant to ‘high stakes’ investment decisions across the ‘water-energy-food’ sectors, using two case-study river basins in Tanzania and Malawi. We compare future climate risk profiles of simple decision-relevant indicators for water-related sectors, derived using hydrological and water resources models, which are driven by an ensemble of future climate model projections. In generating these ensembles, we implement a range of climate model weighting approaches, based on context-relevant climate model performance metrics and assessment. Our case-specific results show the various model weighting approaches have limited systematic effect on the spread of risk profiles. Sensitivity to climate model weighting is lower than overall uncertainty and is considerably less than the uncertainty resulting from bias correction methodologies. However, some of the more subtle effects on sectoral risk profiles from the more ‘aggressive’ model weighting approaches could be important to investment decisions depending on the decision context. For application, model weighting is justified in principle, but a credible approach should be very carefully designed and rooted in robust understanding of relevant physical processes to formulate appropriate metrics.

Item Type:	Article
Official URL:	https://www.springer.com/journal/10584
Additional Information:	© 2021 The Authors
Divisions:	Grantham Research Institute
Subjects:	G Geography. Anthropology. Recreation > GE Environmental Sciences
Date Deposited:	22 Feb 2021 15:03
Last Modified:	01 Dec 2024 04:16
URI:	http://eprints.lse.ac.uk/id/eprint/108886

Actions (login required)

View Item