English
 
Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
Add to Basket
  Local TagsRelease HistoryDetailsSummary

Released
Journal Article

Globally widespread and increasing violations of environmental flow envelopes

Authors

Virkki,  Vili
External Organizations;

Alanärä,  Elina
External Organizations;

Porkka,  Miina
External Organizations;

Ahopelto,  Lauri
External Organizations;

Gleeson,  Tom
External Organizations;

Mohan,  Chinchu
External Organizations;

Wang-Erlandsson,  Lan
External Organizations;

Flörke,  Martina
External Organizations;

/persons/resource/Dieter.Gerten

Gerten,  Dieter
Potsdam Institute for Climate Impact Research;

Gosling,  Simon N.
External Organizations;

Hanasaki,  Naota
External Organizations;

Müller Schmied,  Hannes
External Organizations;

Wanders,  Niko
External Organizations;

Kummu,  Matti
External Organizations;

External Ressource
No external resources are shared
Fulltext (public)

27181oa.pdf
(Publisher version), 10MB

Supplementary Material (public)
There is no public supplementary material available
Citation

Virkki, V., Alanärä, E., Porkka, M., Ahopelto, L., Gleeson, T., Mohan, C., Wang-Erlandsson, L., Flörke, M., Gerten, D., Gosling, S. N., Hanasaki, N., Müller Schmied, H., Wanders, N., Kummu, M. (2022): Globally widespread and increasing violations of environmental flow envelopes. - Hydrology and Earth System Sciences, 26, 12, 3315-3336.
https://doi.org/10.5194/hess-26-3315-2022


Cite as: https://publications.pik-potsdam.de/pubman/item/item_27181
Abstract
Human actions and climate change have drastically altered river flows across the world, resulting in adverse effects on riverine ecosystems. Environmental flows (EFs) have emerged as a prominent tool for safeguarding the riverine ecosystems, but at the global scale, the assessment of EFs is associated with high uncertainty related to the hydrological data and EF methods employed. Here, we present a novel, in-depth global EF assessment using environmental flow envelopes (EFEs). Sub-basin-specific EFEs are determined for approximately 4400 sub-basins at a monthly time resolution, and their derivation considers the methodological uncertainties related to global-scale EF studies. In addition to a lower bound of discharge based on existing EF methods, we introduce an upper bound of discharge in the EFE. This upper bound enables areas to be identified where streamflow has substantially increased above natural levels. Further, instead of only showing whether EFs are violated over a time period, we quantify, for the first time, the frequency, severity, and trends of EFE violations during the recent historical period. Discharge was derived from global hydrological model outputs from the ISIMIP 2b ensemble. We use pre-industrial (1801–1860) quasi-natural discharge together with a suite of hydrological EF methods to estimate the EFEs. We then compare the EFEs with recent historical (1976–2005) discharge to assess the violations of the EFE. These violations most commonly manifest as insufficient streamflow during the low-flow season, with fewer violations during the intermediate-flow season, and only a few violations during the high-flow season. The EFE violations are widespread and occur in half of the sub-basins of the world during more than 5 % of the months between 1976 and 2005, which is double compared with the pre-industrial period. The trends in EFE violations have mainly been increasing, which will likely continue in the future with the projected hydroclimatic changes and increases in anthropogenic water use. Indications of increased upper extreme streamflow through EFE upper bound violations are relatively scarce and dispersed. Although local fine-tuning is necessary for practical applications, and further research on the coupling between quantitative discharge and riverine ecosystem responses at the global scale is required, the EFEs provide a quick and globally robust way of determining environmental flow allocations at the sub-basin scale to inform global research and policies on water resources management.