AQUEDUCT GLOBAL MAPS 2.1: CONSTRUCTING DECISION-RELEVANT GLOBAL WATER RISK INDICATORS

The document details the construction of the Aqueduct Water Risk Atlas, which uses a composite index approach to map global water risks. It describes the development of six modeled indicators (baseline water stress, inter-annual variability, seasonal variability, upstream storage, return flow ratio, and upstream protected land) and the adaptation of six externally sourced indicators (flood occurrence, drought severity, groundwater stress, media coverage, access to water, and threatened amphibians). The methodology involves using an ensemble of regression models to project water withdrawals to 2010, spatial disaggregation to the catchment scale, and a catchment-to-catchment flow accumulation approach for water supply. The final water risk scores are generated through a linear weighted aggregation process, allowing users to customize weights based on their specific sector or risk sensitivity.

• The Aqueduct framework utilizes 12 global indicators to identify spatial variation in water risks, designed for comparative analysis across large geographies rather than site-specific analyses.
• Six indicators were developed by WRI and ISciences LLC using a combination of publicly available datasets and modeling techniques, while the other six were adapted from existing published sources.
• To estimate water withdrawals for 2010, the authors used a combination of mixed-effects (ME) and fixed-effects (FE) regression models, achieving a total R2 between 0.94 and 0.99 across sectors.
• Water supply is modeled using a catchment-to-catchment flow accumulation approach based on the GLDAS-2.0 land surface model, which was selected for its accuracy in simulating annual discharge and variability.
• Baseline water stress (BWS) is calculated as the ratio of total annual water withdrawal to average annual available blue water, specifically measuring chronic stress rather than drought stress.
• The tool employs a linear weighted aggregation approach to calculate overall water risk, allowing users to dynamically adjust weights to reflect different sensitivities or industry-specific risks.
• The authors identify significant data gaps as primary constraints to model accuracy, specifically regarding major infrastructure like interbasin transfers, in-situ water quality, and river gauge measurements.
• Validation of the overall composite index is currently impossible because there are no publicly available datasets of water-related economic or environmental losses.

APA

Gassert, F., Luck, M., Landis, M., Reig, P., & Shiao, T. (2015). AQUEDUCT GLOBAL MAPS 2.1: CONSTRUCTING DECISION-RELEVANT GLOBAL WATER RISK INDICATORS. World Resources Institute. https://wriorg.s3.amazonaws.com/s3fs-public/Aqueduct_Global_Maps_2.1-Constructing_Decicion-Relevant_Global_Water_Risk_Indicators_final_0.pdf

Chicago

Gassert, Francis, Matt Luck, Matt Landis, Paul Reig, and Tien Shiao. AQUEDUCT GLOBAL MAPS 2.1: CONSTRUCTING DECISION-RELEVANT GLOBAL WATER RISK INDICATORS. World Resources Institute, 2015. https://wriorg.s3.amazonaws.com/s3fs-public/Aqueduct_Global_Maps_2.1-Constructing_Decicion-Relevant_Global_Water_Risk_Indicators_final_0.pdf.

Wikipedia

{{cite report |last1=Gassert |first1=Francis |last2=Luck |first2=Matt |last3=Landis |first3=Matt |last4=Reig |first4=Paul |last5=Shiao |first5=Tien |title=AQUEDUCT GLOBAL MAPS 2.1: CONSTRUCTING DECISION-RELEVANT GLOBAL WATER RISK INDICATORS |publisher=World Resources Institute |date=April 2015 |url=https://wriorg.s3.amazonaws.com/s3fs-public/Aqueduct_Global_Maps_2.1-Constructing_Decicion-Relevant_Global_Water_Risk_Indicators_final_0.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{gassert2015aqueduct, author = {Gassert, Francis and Luck, Matt and Landis, Matt and Reig, Paul and Shiao, Tien}, title = {{AQUEDUCT GLOBAL MAPS 2.1: CONSTRUCTING DECISION-RELEVANT GLOBAL WATER RISK INDICATORS}}, institution = {World Resources Institute}, year = {2015}, month = apr, url = {https://wriorg.s3.amazonaws.com/s3fs-public/Aqueduct_Global_Maps_2.1-Constructing_Decicion-Relevant_Global_Water_Risk_Indicators_final_0.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }