This article originally appeared on the CGIAR website.
“Yesterday, I saw in the press that 2024 is on track to be the hottest year ever”, said Matthew McCartney, Research Group Leader at the International Water Management Institute (IWMI), kicking off the NEXUS Gains webinar ‘Water in a heated world.’ With an eye on the rising global thermometer, the 29th and final webinar in the NEXUS Gains Talks series examined the critical connections between global heating and water, all within the changing water-energy-food-ecosystems (WEFE) nexus.
While the current phase of NEXUS Gains finished at the end of 2024, it is clearer than ever that global heating is accelerating the hydrological cycle, leading to more water scarcity and more frequent extreme events. This dynamic drew considerable attention at the recent climate change Conference of Parties (COP29), which this webinar was also perfectly timed to review. “In a world where we can no longer rely on traditional weather patterns, we must rethink how we manage water, which is perhaps our most valuable natural resource”, said McCartney. And in that rethinking WEFE nexus approaches hold great promise.
Stressed rivers
While the final data points come in to declare 2024 the warmest year on record, we don’t have to look far back to find the past record holder: it was 2023.
The World Meteorological Organization recently released the State of Global Water Resources 2023, and Stefan Uhlenbrook, Director of Hydrology, Water, and Cryosphere — and a former NEXUS Gains Lead — explored its findings in the first presentation. The report paints a stark picture of severe stress on global water supplies. “It’s not only the air temperature which is so important, which I always stress, it’s the overall energy in the system”, Uhlenbrook said. His presentation focused specifically on the river discharge data, which reveals a troubling outlook for many basin communities, agriculture, and ecosystems.
In fact, 2023 was the driest year on record for global rivers. “It’s a very aggregated data set, but it is so remarkable that almost half of the planet — the rivers in half of the planet — were drier than normal, and we never had that for the 33 years where we had consistent data”. Although some basins experienced unusually heavy rain or snow and so above normal flows, only 31 percent of rivers were in the “normal” range, reflecting an accelerating five-year trend of abnormal conditions.
Hydrating the “desiccated” COPs
The international community of climate negotiators have access to this clear and shocking information. What have they been doing with it? John Matthews, executive director of the Alliance for Global Water Adaptation, reflected on that question with his personal story of attending climate COPs for 15 years. “From the state of complete desiccation in 2009, there has been a slow hydration that has occurred,” he observed.
Since the 2015 Paris Agreement established the mechanism of Nationally Determined Contributions (NDCs), about 80 percent of the first NDCs mentioned water, and this has been widely celebrated. However, most described water as a hazard, and “floods and droughts” became “the most-used phrase in the COP process”, according to Matthews. More slowly, parties have started to focus on water as a sector – how to pump, pipe, treat, and store it. Still, Matthews says, “what we really want to be able to do is talk about water as a connector… how water spans a lot of critical sectors, energy, agriculture, cities, ecosystem health.” Having recently visited Brazil, which will host COP30, he’s hopeful that this conceptualization of water as a connector will move closer to center stage there.
Water and climate research in motion
Darshini Ravindranath, Research Group Leader on Climate Policies, Finance, and Processes at IWMI, revealed more water connections in current IWMI research. She emphasized that this is not about addressing climate change as a separate issue, but rather acknowledging the unavoidable ways a warming world has shaped the whole of IWMI’s new seven-year strategy to increase water security for those who need it most. The strategy’s first focus area is, appropriately, mitigating water risks. The second is overcoming global inequalities, where the differential impacts of climate change on women and vulnerable groups need particular attention. The third focus area is managing water sustainably, which includes mapping the state of water resources and ensuring this knowledge reaches stakeholders, while also building their capacity.
“Communities already understand the risks that their water systems face due to climate change”, Ravindranath noted. “You know, no one knows the value of water more than someone who walks miles every day to fetch it. But there’s a need to quantify and demonstrate these risks to policy makers and implementers, and to communities as well, so that they are better prepared for the increasing risks that their systems face.” IWMI is doing this with a host of digital models, databases, and tools to sustainably manage the interlinkages within the WEFE nexus.
The next questions
Two panelists responded to the presentations. Xianfu Lu, an independent advisor on adaptation and climate resilience with long experience at the Asian Development Bank, focused on the needs of the moment. She returned to the State of Global Water Resources and the river flow monitoring on which it is based, highlighting that observations are concentrated in the wealthiest countries. This, she pointed out underscores the need for monitoring around the rest of the planet. Reflecting on her 20 years of experience in multilateral development banks, and her work alongside Matthews in COP processes, Lu stressed “Really, we need to move away … from the awareness raising, assessment, planning, to seriously finance and deliver and implement these water based adaptations, and water as a connector”.
Claudia Ringler, NEXUS Gains Co-lead, expressed her gratitude at attending this final webinar with the “NEXUS Gains family”. She reflected, “it’s great to see how the information and knowledge has grown, the number of tools and solutions has increased, and there is now much more push also on the finance side. So, I think we are moving in the right direction, but of course, certainly not fast enough.” Ringler then turned to the NEXUS Gains knowledge–motivation–agency framework, developed during groundwater studies with communities, which she believes is relevant for everyone in a climate crisis. She pointed to motivation as the big remaining gap, declaring, “we have enough knowledge to act.”
The final NEXUS Gains webinar concluded with a significant question from the audience: What is the priority science area to move forward? Uhlenbrook emphasized the need to focus on understanding systems and tracking WEFE interactions through both remote and on-the-ground monitoring. Matthews highlighted the importance of science addressing resilience in water systems, challenging the economics-inspired, efficiency-fixated language still used in water studies. Ravindranath, for her part, turned to finance and research to understand the reasons for its massive gaps. This is particularly crucial in the wake of COP29: a “finance COP” that left many observers dismayed.
“As scientists, I think we tend to think about finance as something that the other people need to do, in the water sector particularly,” Ravindranath said. As the temperature rises, that may be an assumption we can no longer rely on.