Climate change could have increased the heaviest rainfall over a short period of time in the worst-hit areas by about 50%, according to a study by an international group of climate scientists. The floods were a one-in-100-year event, but similar events are likely to become more frequent in the future as global temperatures continue to rise, scientists said. Scientists were unable to quantify exactly how much more likely flooding was due to the climate crisis because of the high degree of natural variability in monsoons in the region. However, they said there was a 1% chance of such heavy rainfall occurring each year, and an event like this summer’s flooding would probably be much less likely in a world without human-made greenhouse gas emissions. Friederike Otto, senior lecturer at the Grantham Institute for Climate Change and the Environment at Imperial College London, said the “fingerprints” of global warming could be clearly seen in the floods in Pakistan, which were consistent with what scientists of the climate had predicted extreme conditions. weather. “We can say with great confidence that [the rainfall] it would be less likely to happen without climate change,” he said. “Rainfall intensity has increased quite a bit.” Historical records have shown that heavy rainfall has increased dramatically in the region since humanity began pumping greenhouse gases into the atmosphere, the scientists found. Otto added: “Our evidence suggests that climate change played a significant role in the event, although our analysis does not allow us to quantify how big a role it was. This is because it is an area with very different weather from one year to the next, which makes it difficult to see long-term changes in observed data and climate models.” About a third of Pakistan has been affected by floods, with water covering more than a tenth of the country after more than three times the average rainfall in August. Nearly 1,500 people have lost their lives and 33 million people have been affected, while 1.7 million homes have been destroyed. For the country as a whole it was the wettest August since 1961 and for the two southern provinces of Sindh and Balochistan the wettest on record, with about seven to eight times more rain than usual. While increased rainfall was influenced by climate change, local factors also played a role in flooding and its effects. For example, forests in the region have been cut down for many decades and mangrove swamps removed, while man-made dams, irrigation and other changes in water courses also have an impact on natural flood patterns. Poor infrastructure, such as flimsily built houses in flood-prone places, also results in more people suffering as a result of floods. Ayesha Siddiqi, Assistant Professor in the Department of Geography at the University of Cambridge, said:[Flooding] it has struck places where local socio-ecological systems were already quite compromised. This disaster was the result of vulnerability built up over a number of years and should not be seen as the result of a single event.” Pakistan faces a cost of at least $30 billion in damages, with the loss of food crops alone amounting to about $2.3 billion, a particularly heavy burden at a time of rising food prices around the world. About 18,000 square kilometers of arable land has been destroyed, including about 45% of the cotton crop, one of Pakistan’s main exports, and about 750,000 animals have been killed. The most important stories on the planet. Get all the week’s environmental news – the good, the bad and the must-haves Privacy Notice: Newsletters may contain information about charities, online advertising and content sponsored by external parties. For more information, see our Privacy Policy. We use Google reCaptcha to protect our website and Google’s Privacy Policy and Terms of Service apply. The Pakistan floods report came from the World Weather Attribution, a group of scientists from around the world trying to discern the impact of human-caused climate change on extreme weather events. They analyze such events in real time to produce quick answers about whether climate change has affected extreme weather events, a process that used to take years. Previous studies have shown that climate change worsened heatwaves in India, Pakistan and the UK earlier this year, and floods in Brazil. WWA found last year that heatwaves in the US Pacific Northwest would be “virtually impossible” without climate change. A recent Guardian analysis revealed the extent to which the climate crisis is “overloading” weather events, with devastating consequences. Otto said countries meeting in November for the Cop27 UN climate conference in Egypt should take into account the extreme weather events the world has seen this year and in recent years. “The lesson is that this is going to become more likely, probably much more likely. Becoming more resilient is very important.”
