We cannot predict the future. But that doesn’t mean we can’t plan for it. Futureproofing climate action demands an understanding of how water and climate are inextricably linked and how to leverage those links to build resilience.

As Brazil’s COP30 approaches, to have any chance of meeting climate goals and minimising impacts of climate change there must be a shift in focus from solely greenhouse gas emission reduction to a more comprehensive approach that prioritizes adaptation and resilience. Understanding the role of water in climate unlocks new tools for adaptation, mitigating climate change and building resilience.

While the GHG focus remains paramount it is increasingly clear that our climate is changing and that society writ large is unprepared for these changes.

At the same time, adaptation and resilience – A&R – have emerged as a second area of focus aimed at building resilience in light of the observed speed and magnitude of climate impacts. This volatility is most acutely expressed through the global water cycle: through floods, extreme rainfall, droughts, and shrinking glaciers, which have cascading impacts across society.

This complementary focus on adaptation and resilience necessitates an understanding of how water and climate are linked and strategies to address the linkages and feedback loops.

Climate change is intensifying the water cycle

The climate cycle and water cycle are inextricable. At a global level, we can confidently say that climate change is intensifying the water cycle, as a warmer atmosphere holds more water vapor. Water vapor in the atmosphere becomes precipitation (rain, snow, ice), falling on land surfaces and the oceans, and turning back into water vapor more quickly than in the recent past. We can expect that as air temperatures rise, the process of intensifying the water cycle will also accelerate. Here are five ways water and cliamte are inextricably connected, highlighting where opportunities for building better climate action lie.

1. The impact on the water cycle is complex

Climate change impacts on the water cycle are complex and often counterintuitive. For instance, regions that are experiencing more drought are also experiencing more flooding and extreme precipitation. Floods may occur during droughts, or the two may closely follow each other. There is no single or simple story anywhere.

2. Climate change is increasing competition for water

Competition for water resources is increasing, and climate change is helping drive increased competition. While domestic water use often increases with higher air temperatures, freshwater resources are also essential for many other important economic activities, including energy production, manufacturing, and agriculture.

For most economic sectors, water consumption is also growing, which can place households and these sectors in competition with each other. Water storage, treatment, transport, and governance are critical elements in managing competition. Some ecosystems are also seeing intensifying water use, such as many tropical and temperate zone forests.

3. Resilience ensures reliability

Reliable water access is important for households, communities, and countries. Resilience is becoming a more important mechanism for ensuring reliability. Building resilience demands changing how water resources are used, shared, treated, transported, and stored so that access can continue without interruption or can be restored following a disruption.

4. Efficiency is not resilience

Water use efficiency can be a part of ensuring reliability, but sometimes efficiency is in tension with resilience. A more efficient system is not necessarily more resilient. For example, Just in Time manufacturing strategies, with dispersed manufacturing sites and global supply chains that generally reduce or eliminate slack and surplus inventory, may offer greater levels of efficiency but also greater exposure to shocks, creating an efficient but brittle system.

5. Resilience means we don’t need to predict the future

Predicting future water conditions is challenging – where climate models excel at air temperature, they struggle with the water cycle. As models adapt to rapid climate shifts, a focus on resilience helps build robust systems - we don’t need to wait until we can predict the unpredictable before taking action that saves lives and livelihoods.

Water has always been a driver in where we choose to settle, and if those conditions changed be it climate impacts or something else: we relocated. Today, displacement and migration pose significant political and economic issues, trapping communities in fragile systems. Resilience will help ensure that no one is left behind.

Five ways water is climate