The Toronto Star – From deluges to drought: Climate change speeds up water cycle, triggers more extreme weather
“Basically, global warming is turning the atmosphere into a bigger sponge so it can soak up more moisture ... and then when the conditions are right for rainfall, it’s like squeezing that sponge, you get more moisture coming out faster.”
People walk through a part of the Amazon River that shows signs of drought, in Santa Sofia, on the outskirts of Leticia, Colombia, Oct. 20, 2024. (AP Photo/Ivan Valencia, File)
This recent article from The Toronto Star highlights how climate change is accelerating the global water cycle, leading to more frequent and extreme weather events— including prolonged droughts and catastrophic floods. As global temperatures rise, driven largely by the continued burning of fossil fuels, the atmosphere is able to hold more moisture. This intensifies both dry and wet conditions, with serious consequences for ecosystems, infrastructure, and human safety.
Experts explain that the hydrological cycle— the continuous movement of water between the Earth’s surface and the atmosphere— is speeding up. A warmer atmosphere pulls more moisture from soil, vegetation, and surface water, creating drier conditions in many regions. Yet when that moisture is released, it often results in short, intense downpours that can overwhelm dams, flood communities, and wash away infrastructure. For every 1°C increase in temperature, the atmosphere can hold about 7% more water vapor, making these deluges more likely.
The oceans play a critical role in this process. As they absorb most of the planet’s excess heat, they expand and drive sea level rise, while also fueling more intense storms. In 2023, for instance, Mediterranean storm Daniel brought heavy rains that led to dam failures and widespread flooding in Libya, devastating the coastal city of Derna. Climate scientists confirm that warming made that event significantly more likely.
Climate change is also altering snowpack dynamics— another key part of the water cycle. In many regions, less snow is falling, and what does fall is increasingly lost to evaporation or absorbed by dry soils. This reduces the amount of meltwater available for agriculture and drinking water, and shifts seasonal water availability in ways that threaten water security.
With these extremes becoming more common, the need for better forecasting and long-term planning is urgent. Projects like Canada1Water (C1W) are helping meet this need by offering national-scale climate and hydrological data to support science-based decision-making. By understanding how Canada’s water systems are changing, Canada1Water equips policymakers, researchers, and communities with the insights needed to build climate resilience and safeguard water resources.
Click here to read the article in The Toronto Star.