Study finds planetary waves linked to wild summer weather have tripled since 1950
'A classic pattern would be like a high pressure out west (in the United States) and a low pressure back East and in summer 2018, that's exactly what we had,' Mann said. 'We had that configuration locked in place for like a month. So they (in the West) got the heat, the drought and the wildfires. We (in the East) got the excessive rainfall.'
'It's deep and it's persistent,' Mann said. 'You accumulate the rain for days on end or the ground is getting baked for days on end.'
The study finds this is happening more often because of human-caused climate change, mostly from the burning of fossil fuels, specifically because the Arctic warms three to four times faster than the rest of the world. That means the temperature difference between the tropics and the Arctic is now much smaller than it used to be and that weakens the jet streams and the waves, making them more likely to get locked in place, Mann said.
'This study shines a light on yet another way human activities are disrupting the climate system that will come back to bite us all with more unprecedented and destructive summer weather events,' said Jennifer Francis, a climate scientist at the Woodwell Climate Research Center who wasn't involved in the research.
'Wave resonance does appear to be one reason for worsening summer extremes. On top of general warming and increased evaporation, it piles on an intermittent fluctuation in the jet stream that keeps weather systems from moving eastward as they normally would, making persistent heat, drought, and heavy rains more likely,' Francis said.
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Hindustan Times
a day ago
- Hindustan Times
We must stay prepared for extreme heat and flooding
In March 2025, the World Meteorological Organization confirmed what climate scientists had warned: 2024 was the first year to exceed 1.5 °C above pre‑industrial levels, reaching roughly 1.55–1.6 °C nationwide. That translated into more than 150 unprecedented weather disasters worldwide: heatwaves, floods, storms which displaced over 800,000 people in 2024 and inflicted grave damage on life, livelihoods, crops and infrastructure. The intensity of the incessant rainfall was higher in the eastern suburbs of Ghatkopar, Mankhurd, Govandi, LBS Road in Vikhroli and Bhandup, which are considered chronic flooding spots. (Praful Gangurde /HT Photo) Sea levels rose at 4.7 mm/year in 2024 twice the rate of the early 2000s while global ice losses, record ocean heat, and shrinking Arctic and Antarctic sea ice reached unprecedented lows (WMO). The resulting extremes of heat, drought, storms, flooding affected societies from Asia to the Americas. According to Climate Central and other agencies, about half of humanity some 4 billion people experienced at least one extra month of extreme heat between May 2024 and May 2025 compared to historical norms. In nearly every country, extreme heat days have at least doubled due to global warming. Meanwhile globally, heatwaves remain the deadliest weather event. Asia recorded 1,301 deaths during a June 2024 heatwave near Mecca. Japan's 2024 heatwaves caused 123 deaths and over 37,000 heatstroke hospitalisations. In North America, the 2024 heatwaves killed over 1,000 people in the US and 155 in Mexico, with Death Valley hitting 54°C. Europe endured record heat in 2024–25 causing approximately 2,300 deaths across 12 cities including Spain, Portugal, and the UK. Extreme rainfall and flooding were equally widespread. Floods in Pakistan, Senegal, Italy and Brazil destroyed homes and crops. These disasters also triggered the highest level of climate-related displacement since 2008, over 824,000 people in 2024. As part of the global maelstrom, India has become a climate flashpoint, with nearly 60% of districts representing 76% of the population fall into high or very high heat-risk categories. IIT Gandhinagar reports some 10,000 flash-flood events annually even in central and western India impacting over 90 million hectares. Between April and July 2025, an early heatwave peaked at 48 °C in Rajasthan, linked to at least 455 heat-related deaths. Extreme weather occurred on 88% of days in 2024, killing almost 3,000 people and destroying 80,000 homes (Centre for Science and Environment). These qualify as part of a larger global pattern: warming disproportionally impacting South Asia, Africa, Latin America and the island-State regions least responsible for emissions yet most vulnerable. While mitigation remains vital, adaptation building resilience now is a matter of survival. The UN's Adaptation Gap Report 2023 estimates that developing countries need $194–366 billion annually by 2030, yet receive less than 10% (WMO, UNEP). Every $1 spent on adaptation yields $13 in avoided damage (WMO). As climate extremes become more frequent and severe, countries must shift from reactive relief to proactive resilience. Across the globe, innovative strategies are emerging that offer replicable models of adaptation and preparedness. These best practices, drawn from diverse geographies, highlight both the urgency and opportunity to act now. * Cool cities: Urban heat islands amplify the deadly impact of rising temperatures. Cities like Ahmedabad in India have pioneered early interventions. Its Heat Action Plan focused on public education, early warnings, and hydration stations has significantly reduced heatstroke fatalities over the past decade. Elsewhere, Melbourne combats urban heat by planting over 3,000 shade trees annually, while Paris has designated more than 800 public cooling centres. These low-cost, high-impact urban strategies demonstrate how city design and green infrastructure can save lives and enhance liveability amid rising heat extremes. * Flood protection via nature-based solutions: Flood management need not rely solely on grey infrastructure. The Netherlands' Room for the River programme, which restores floodplains and allows rivers to flow more naturally, has proven effective in mitigating flood risks while enhancing ecosystems. In Southeast Asia, countries like Indonesia, Vietnam, and the Philippines are restoring mangroves to shield vulnerable coastlines. In India, the East Kolkata Wetlands naturally treat wastewater and absorb stormwater, while Chennai and Bengaluru have seen success with Miyawaki forests that not only reduce runoff but also cool microclimates. These examples reveal how nature-based solutions can build dual resilience: protecting lives while restoring biodiversity. * Smarter warning systems and community-based responses: According to the World Meteorological Organization, only about half of the world's countries have effective early warning systems in place. Bangladesh, however, has become a global leader in this space. Through improved cyclone forecasting, pre-emptive evacuations, community drills, and a network of shelters, it has drastically reduced cyclone-related deaths over the years. Countries like India, Nepal, and Brazil should scale up similar models that combine SMS-based alerts, local volunteer brigades, and decentralised command centres to ensure faster and more inclusive responses. * Health system readiness: Climate events often turn into public health crises. Heatwaves exacerbate risks of heatstroke, dehydration, and respiratory illness, while floods lead to outbreaks of waterborne and vector-borne diseases. Japan has institutionalised its heat alert system into school protocols, urban planning, and public health advisories, setting a global benchmark. In India, there is an urgent need to establish district cooling hubs, hydration centres, and train primary healthcare workers to respond to heat- and flood-related illnesses. Post-disaster mental health support also deserves more systematic integration into national health strategies. * Financing resilience: A major bottleneck in scaling preparedness is finance. However, innovative models are emerging. From 2028, Indian banks will mandate climate-risk disclosures and stress testing for businesses, a critical first step toward climate-informed financial systems. Kenya offers another powerful model through its County Climate Change Funds, which decentralise adaptation finance and align spending with local priorities. Globally, climate adaptation finance must scale through tools like green bonds, local climate funds, and weather-indexed insurance schemes that offer quicker recovery and risk-sharing mechanisms, especially for the most vulnerable. * Empowering local communities: At the frontlines of every climate disaster are local communities often under-resourced but deeply adaptive. Grassroots organisations, such as self-help groups in India, climate response brigades in Spain, and youth volunteer corps in Latin America, are proving to be first responders, educators, and long-term resilience builders. Providing these groups with climate training, microgrants, and institutional support can dramatically expand the reach and relevance of adaptation programmes. Climate resilience must be seen not as a top-down mandate, but as a collaborative effort rooted in local knowledge and leadership. Collectively, these strategies underscore a central truth: resilience is local, contextual, and most effective when co-created. While global climate conventions continue to guide broad policy frameworks, it is these grounded, tested, and community-centric models that offer the most hope in a rapidly warming world. The world passed the 1.5 °C threshold in 2024. Without urgent emissions reductions, we are on track for 2 °C warming by 2030, which would multiply climate extremes. That means hotter summers, erratic monsoons, rising seas, degraded food systems, and population migrations on a scale few nations are prepared to handle. From the Philippines to Pakistan, from Sardinia to Sahel, people have been displaced, injured, or killed by disasters already made more likely by human-caused warming. We have solutions and examples. What is lacking is the political will, financing, and collective urgency. Whether in Delhi, Dhaka, Dakar, or Denver, adaptation is now the frontline of the climate crisis. Adaptation is not a fallback, it is the defence. How hardened are our cities, health systems, communities and economies? That will determine how many lives are saved, and how much suffering is averted. The question is no longer will we be hit? How hard and how ready are we? This article is authored by Ananya Raj Kakoti, scholar, international relations, Jawaharlal Nehru University.
Time of India
16-07-2025
- Time of India
Santa's village swelters: Even travelling to the Arctic Circle won't save you from a heatwave
Synopsis Rovaniemi, Finland, witnessed a record-breaking 30°C, highlighting climate change's impact in the Arctic. Across Europe, the intense heatwave has resulted in numerous fatalities, with studies indicating climate change made it significantly more deadly. While some European nations are implementing heat regulations for outdoor workers, concerns remain regarding enforcement and comprehensive coverage.
&w=3840&q=100)
Business Standard
10-07-2025
- Business Standard
Life-threatening heat domes challenge forecasters amid climate change
Record-breaking temperatures seared the eastern US last month, leading to power emergencies across the region. The cause: an enormous ridge of high pressure that settled on the region, known as a heat dome. This phenomenon has also already struck Europe and China this summer, leading to the temporary closure of the Eiffel Tower and worries about wilting rice crops, respectively. But while heat domes are easy to identify once they strike, they remain difficult to forecast — a problematic prospect in a warming world. 'There is a world of difference between normal summer heat and record or near-record breaking extreme heat,'' said Scott Handel, lead forecaster at the US Climate Prediction Center. 'While normal summer heat can be dangerous, extreme heat can be particularly life threatening.' Heat dome is used to describe extreme heat waves to the general public that captures their menace, said Zach Zobel, a scientist at the Woodwell Climate Research Center. They occur when a large high pressure system settles over a specific area, baking it under stagnant air and the sun's unrelenting energy. That locks in more heat and can intensify the area of high pressure, creating a self-reinforcing cycle. Heat domes can occur at any time of year, but they're particularly dangerous during summer, with wide-ranging societal and economic impacts in the billions. Wildfires and droughts are often the byproduct of extreme heat and have caused some of the largest climate-related disasters in the US. From 1980 to 2024, 23 wildfires caused $147.9 billion in damage and killed 537 people while 32 droughts extracting a toll of $367.6 billion and killed 4,658, according to a database of billion-dollar disasters that was updated until this year by the US Centers for Environmental Information. Between 1979 and 2022, more than 14,000 Americans died directly from heat-related causes according to death certificates, the US Environmental Protection Agency said. In the summer of 2022, an estimated 61,672 people died from heat related causes, according to a July 2023 paper published in the journal of Nature Medicine. A prolonged heat dome can stress crops, particularly heavily traded corn and soybeans. Electricity prices and demand soar when temperatures rise and stay elevated for prolonged periods, said Anthony Chipriano, a forecaster at Vaisala. The dead, hot air under these massive systems can limit the tonnage carried by airliners, kink railroad tracks and crimp the output of wind turbines. For these reasons, meteorologists are opening their toolboxes to try and figure out where and when heat domes will strike. 'I don't have the same ability to predict heat domes like cold air outbreaks, but there are some trends,'' said Judah Cohen, director of seasonal forecasting at Atmospheric and Environmental Research Inc. Meteorologists know, for example, the jet stream — a river of fast-flowing air girdling the globe — naturally migrates northward in summer and they can measure how fast it moves. That metric is known as the Global Atmospheric Angular Momentum, and it's among the best predictors for heat domes, said Matt Rogers, president of the Commodity Weather Group. When the value is low, as it is two weeks ago, 'it can be a leading indicator of widespread, middle latitude heat ridges,'' he said. The latest indication from GLAAM is the return of relatively cooler weather, Rogers said. July is tracking warmer than the 30-year average but cooler than the mean of the last 10 years and the least hot since 2021, he said. Some weather phenomenon like the polar vortex can be spotted several weeks in advance while others like El Nino can be predicted months ahead of time. But heat domes have a much shorter lead time. The US National Weather Service studies probable outcomes of emerging weather patterns, said Handel of Climate Prediction Center, which is what allowed the agency to start issuing heat warnings ahead of the dome that gripped the East Coast even as the region experienced relatively cool weather. The service issued a moderate risk of extreme heat on June 13, when the high temperature in New York's Central Park was still just 78F. Ten days later, the temperature reached 96F, and it hit 99F the day after, both daily records. Federal forecasters also rely on statistical analysis of past patterns compared to what computer models are projecting as well as measures like soil moisture since drier land means higher temperatures to put their heat forecast together. Climate change has warmed the planet, particularly the high latitudes. That influences heat domes in two ways. The first is their northward migration. That phenomenon played out in 2023 as a large ridge of high pressure parked across western-to-central Canada and kicked off a record wildfire season. The second is changes to the jet stream. The temperature gradient between the poles and the tropics helps keep the jet stream taut, allowing it to push weather patterns along after a few days, Zobel said. But as the Arctic warms faster than the rest of the planet, that gradient weakens and is akin to loosening the grip on a rope. The resulting slack can cause the jet stream to kink, bend and buckle. The river of air can also sometimes split, creating a 'kind of a no-man's land' that holds heat domes in place, Cohen said. Still, Arctic warming's exact impact on the jet stream is an area of active research, Simpson said. Some papers haven't been able to show the impacts that adherents of the weakening theory suggest, and others have come up with opposite results. What is clear is that temperatures are rising everywhere, said Karen McKinnon, an associate professor at the Institute of the Environment and Sustainability at the University of California Los Angeles, and it doesn't take that much of an increase on the hottest days to 'make summers feel substantially more extreme.' With more heat trapped in the system and weather patterns that can lock it in place over specific locations, that makes the need for more accurate forecasts with longer lead times all the more important. 'The weather event that kills more than anybody else on the planet is heat and that is certainly true in the United States,' Zobel said. 'It is silently a big human health impact.'
