Protecting the planet’s bloodstream: feasible and just opportunities to safeguard freshwater’s Earth system functions

Freshwater has a fundamental role in regulating the state of the Earth system.

Various human actions modify the water cycle, disturbing the Earth system functions it provides, such as mediating the planets energy balance and sustaining ecosystems.

Humanitys impact on these functions has not been quantified comprehensively, nor do we know what human actions drive water cycle modifications (WCMs) in different parts of the world.

This knowledge gap has made it impossible to acknowledge freshwater's crucial Earth system functions in decision-making.

As human pressures on the water cycle continue to increase, there is an urgent need for bridging the gap between Earth system science and water management and governance, to safeguard freshwaters life-supporting Earth system functions.

AQUAGUARD rises to this challenge by 1) providing quantifications of the full extent of humanity's disturbance of the Earth system functions of freshwater, globally and in a spatially explicit manner, using novel indicators and spatial delineations; 2) using novel computational methods that will provide new insights into the complex driver interactions behind WCMs; 3) quantifying crucial Earth system impacts of WCMs, using modelling and meta-analysis, and 4) identifying feasible and just opportunities to safeguard freshwaters Earth system functions, using AQUAGUARDs quantifications combined with novel indicators of feasibility and equity aspects of freshwater change at scales that are appropriate for water management and governance.AQUAGUARD addresses fundamental knowledge gaps at the intersection of hydrology, ecology and biogeochemistry, and provides various new methods and ground-breaking scientific results that will illustrate water as an integral part of the Earth system.

By doing so, the project opens up new research avenues within and across these fields and expands perspectives in water management and governance from predominantly local to local-to-global.