The Guardian - ‘Nature is striking back’: flooding around the world, from Australia to Venezuela
“Scientists have said flash floods are becoming a problem in some countries, with short, severe bursts of rain causing anything from annoyance to mayhem. Some places are whiplashing between severe drought and these sudden downpours, heightening the risk of mudslides and other knock-on effects.”
2022 has been a devastating year for flood related catastrophes; heavy rains and rising waters have caused havoc in countries around the world including Nigeria, Venezuela, Australia, Pakistan, Cambodia, Thailand and Vietnam. The Guardian provides an overview of the state of floods across the world.
Click here to read the article in the Guardian.
Projected percentage change in annual precipitation from the 1986 to 2005 reference period. Changes are for the end of the century assuming a high global emission scenario. Source: https://www.canada.ca/en/environment-climate-change/services/climate-change/canadian-centre-climate-services/basics/trends-projections/changes-precipitation.html
As average air temperatures continue to climb around the world, the atmosphere is able to carry higher levels of moisture. This has different impacts in different regions around the world, but in Canada we expect that climate change will on average result in more precipitation, especially in Northeastern Canada (see figure).
Unfortunately, the extra rain will tend to all fall in fewer, more extreme rainfall events. The increased temperatures also cause higher rates of evapotranspiration, so in between these rain events the land surface will tend to be drier. The end result is that the rain that does fall will tend to runoff overland more than it has in the past, and less water will infiltrate into soil, through wetlands, and other pathways that tend to slow the water down. With extra overland flow, water flows directly into rivers and we will see intermittent peaks in river elevation, but the decreased water in the 'slow' flow paths causes an overall drop in surface water levels. But paradoxically, in between these low-flow periods we are likely to see more frequent and damaging peak flows (i.e. flooding).
As the Guardian outlines, we are now seeing the impacts of these extraordinary floods. Flooding in Pakistan this year resulted in >1700 deaths, impacted >33 million people, and resulted in an estimated $40 billion USD in damages. In Nigeria, flooding killed >600, displaced another 1.4 million people and completely or partially destroyed over 200,000 homes. Meanwhile, heavy rains are flooding cities and towns across south-east Australia, with the Australian town of Kerang preparing for it’s second “one-in-a-century” flood in only 11 years (and this is following massive flooding in in Queensland and northern New South Wales only 6 months ago).
Click here to read the article in the Guardian.
The Canada1Water project will help Canadians to adapt to and mitigate the impacts of climate change by arming communities and water resources specialists with a decision support system (DSS) that can support community-based impact analyses including how flood and drought frequency (and magnitude) may potentially change, for mid- and end-century time intervals.