Latest news with #MariamZachariah
Euronews
17-07-2025
- Climate
- Euronews
Scientists slam ‘injustice' of scarce Global South climate studies
Unclear results from a study into the heavy rain which triggered a deadly landslide in Colombia and floods in Venezuela reflect a 'scientific injustice' between rich and poor countries, scientists have warned. The rapid analysis by World Weather Attribution could not find clear evidence that climate change influenced these downpours. But the researchers highlight that high uncertainties in the results mean the possibility of heavier rain should not be ruled out. Like many Global South countries, Colombia and Venezuela are highly vulnerable to climate change, but their complex tropical climates are severely under-researched. 'A core aim of World Weather Attribution is to improve understanding of extreme weather in Global South countries,' says Dr Mariam Zachariah, research associate at the Centre for Environmental Policy, Imperial College London. 'Many have tropical climates, which are inherently difficult to study – a combination of mountains, coasts, rainforests and complex weather systems means rainfall is varied, intense and challenging to capture in climate models. 'Unfortunately, many countries with tropical climates have limited capacity to do climate science, meaning we don't have a good understanding of how they are being affected by climate change.' Did climate change make heavy rainfall worse in Colombia and Venezuela? In late June, intense rainfall swept across Colombia and Venezuela, causing widespread flooding and deadly landslides. Near Medellín in Colombia, a landslide buried homes and killed 27 people. In Venezuela, overflowing rivers ruined homes, wiped out crops and displaced thousands of people. To try and work out the role climate change played in this heavy rain, scientists looked at rainfall over two regions: the Colombian Andes and the Venezuelan Llanos. Historical data showed that neither event was particularly rare. In today's climate with 1.3°C of warming, the three months of rainfall in Colombia can be expected every ten years on average, while in Venezuela, similar five-day spells of heavy rain can be expected every three years. The study also found a drying trend with seasonal rainfall in Colombia, now 12 per cent less likely and less intense, while the chance of heavy rainfall over Venezuela was 9 per cent lower. Climate models also showed a drying trend in Colombia, but that was less clear in Venezuela. There were high uncertainties in the global data sets and models that the researchers looked at. Both Colombia and Venezuela have complex tropical climates, and they say the possibility of heavier rain shouldn't be ruled out. The Intergovernmental Panel on Climate Change projects a range of changes in rainfall in the region - but that prediction also has low confidence. Why are weather attribution studies in the Global South often inconclusive? World Weather Attribution says high uncertainty is typical in rainfall studies of Global South countries. Dr Zachariah points to another recent study on deadly floods in the Democratic Republic of Congo earlier this year, which also returned inconclusive results. The DRC is a developing country with a tropical climate. Historically, climate science has focused on wealthier countries, making data sets and models less accurate for places like these. Latin America is one of the most understudied regions in the world – this analysis is the first attribution study on a weather event in Venezuela and just the third for Colombia. 'Yet again, we've studied an extreme rainfall event in a Global South country and come up with unclear results,' explains Dr Joyce Kimutai, research associate at the Centre for Environmental Policy, Imperial College London. 'This is a scientific injustice.' Dr Kimutai emphasises that rich countries, which have contributed the most to global warming, are able to invest in research to understand how they will be affected by changing weather extremes. Poor countries, which have contributed the least but are the most vulnerable, have limited funds for climate research. 'This reduces their ability to understand what the future might bring and how they should prepare.' She adds that Latin America, the Caribbean and Africa need more extreme weather attribution studies. But the global data sets and climate models they use for these studies often perform poorly in these regions. 'Investing in weather stations and climate science will help. That money really should come from rich countries.' 'More science will save lives' While landslides and flash floods are common in both countries, the expansion of informal communities on hillsides is increasing the risk of disaster, the study highlights. And, while the landslide in Colombia was not extreme by historical standards, it still led to a significant loss of life. Researchers say many people living in these areas have been displaced by past disasters or conflicts and are moving closer to cities to search for better job opportunities. The experts add that adaptation efforts such as early warning systems and forest conservation can be cost-effective ways to reduce risks. 'Extreme weather is non-stop in Colombia and Venezuela. One year we face devastating flash floods; the next, severe droughts and wildfires,' says Professor Paola A. Arias, Professor at the Universidad of Antioquia in Colombia. 'It doesn't take much for a weather event to become a disaster because many people are already vulnerable. The late June downpours weren't especially unusual, however, they still triggered a landslide that killed 27 people.' Professor Arias adds that, while it's unclear if climate change increased rainfall in this case, it's almost certainly increasing the risk of drought, heatwaves and wildfires in both countries. 'We urgently need more investment in climate science to understand shifting risks and prepare for what's ahead. More science will save lives.'
Yahoo
17-07-2025
- Climate
- Yahoo
‘Scientific injustice': Deadly rainfall in Colombia and Venezuela highlights need for more research
Unclear results from a study into the heavy rain which triggered a deadly landslide in Colombia and floods in Venezuela reflect a 'scientific injustice' between rich and poor countries, scientists have warned. The rapid analysis by World Weather Attribution could not find clear evidence that climate change influenced these downpours. But the researchers highlight that high uncertainties in the results mean the possibility of heavier rain should not be ruled out. Like many Global South countries, Colombia and Venezuela are highly vulnerable to climate change, but their complex tropical climates are severely under-researched. 'A core aim of World Weather Attribution is to improve understanding of extreme weather in Global South countries,' says Dr Mariam Zachariah, research associate at the Centre for Environmental Policy, Imperial College London. We don't have a good understanding of how they are being affected by climate change. 'Many have tropical climates, which are inherently difficult to study – a combination of mountains, coasts, rainforests and complex weather systems means rainfall is varied, intense and challenging to capture in climate models. Related Heatwaves, floods and sea level rise: UK weather extremes are increasing, Met Office confirms 'Crimes against nature and people': How a global crackdown in the Amazon unfolded 'Unfortunately, many countries with tropical climates have limited capacity to do climate science, meaning we don't have a good understanding of how they are being affected by climate change.' Did climate change make heavy rainfall worse in Colombia and Venezuela? In late June, intense rainfall swept across Colombia and Venezuela, causing widespread flooding and deadly landslides. Near Medellín in Colombia, a landslide buried homes and killed 27 people. In Venezuela, overflowing rivers ruined homes, wiped out crops and displaced thousands of people. To try and work out the role climate change played in this heavy rain, scientists looked at rainfall over two regions: the Colombian Andes and the Venezuelan Llanos. Historical data showed that neither event was particularly rare. In today's climate with 1.3°C of warming, the three months of rainfall in Colombia can be expected every ten years on average, while in Venezuela, similar five-day spells of heavy rain can be expected every three years. The study also found a drying trend with seasonal rainfall in Colombia, now 12 per cent less likely and less intense, while the chance of heavy rainfall over Venezuela was 9 per cent lower. Climate models also showed a drying trend in Colombia, but that was less clear in Venezuela. There were high uncertainties in the global data sets and models that the researchers looked at. Both Colombia and Venezuela have complex tropical climates, and they say the possibility of heavier rain shouldn't be ruled out. The Intergovernmental Panel on Climate Change projects a range of changes in rainfall in the region - but that prediction also has low confidence. Why are weather attribution studies in the Global South often inconclusive? World Weather Attribution says high uncertainty is typical in rainfall studies of Global South countries. Dr Zachariah points to another recent study on deadly floods in the Democratic Republic of Congo earlier this year, which also returned inconclusive results. The DRC is a developing country with a tropical climate. Historically, climate science has focused on wealthier countries, making data sets and models less accurate for places like these. Latin America is one of the most understudied regions in the world – this analysis is the first attribution study on a weather event in Venezuela and just the third for Colombia. 'Yet again, we've studied an extreme rainfall event in a Global South country and come up with unclear results,' explains Dr Joyce Kimutai, research associate at the Centre for Environmental Policy, Imperial College London. 'This is a scientific injustice.' Dr Kimutai emphasises that rich countries, which have contributed the most to global warming, are able to invest in research to understand how they will be affected by changing weather extremes. Poor countries, which have contributed the least but are the most vulnerable, have limited funds for climate research. 'This reduces their ability to understand what the future might bring and how they should prepare.' She adds that Latin America, the Caribbean and Africa need more extreme weather attribution studies. But the global data sets and climate models they use for these studies often perform poorly in these regions. 'Investing in weather stations and climate science will help. That money really should come from rich countries.' 'More science will save lives' While landslides and flash floods are common in both countries, the expansion of informal communities on hillsides is increasing the risk of disaster, the study highlights. And, while the landslide in Colombia was not extreme by historical standards, it still led to a significant loss of life. Researchers say many people living in these areas have been displaced by past disasters or conflicts and are moving closer to cities to search for better job opportunities. The experts add that adaptation efforts such as early warning systems and forest conservation can be cost-effective ways to reduce risks. Related Climate change tripled death toll of latest European heatwave, first ever rapid study finds New index reveals countries in the 'red zone' of climate vulnerability - including two in Europe 'Extreme weather is non-stop in Colombia and Venezuela. One year we face devastating flash floods; the next, severe droughts and wildfires,' says Professor Paola A. Arias, Professor at the Universidad of Antioquia in Colombia. It doesn't take much for a weather event to become a disaster because many people are already vulnerable. 'It doesn't take much for a weather event to become a disaster because many people are already vulnerable. The late June downpours weren't especially unusual, however, they still triggered a landslide that killed 27 people.' Professor Arias adds that, while it's unclear if climate change increased rainfall in this case, it's almost certainly increasing the risk of drought, heatwaves and wildfires in both countries. 'We urgently need more investment in climate science to understand shifting risks and prepare for what's ahead. More science will save lives.'
Euronews
17-07-2025
- Climate
- Euronews
Scientists slam ‘scientific injustice' in Global South climate studies
Unclear results from a study into the heavy rain which triggered a deadly landslide in Colombia and floods in Venezuela reflect a 'scientific injustice' between rich and poor countries, scientists have warned. The rapid analysis by World Weather Attribution could not find clear evidence that climate change influenced these downpours. But the researchers highlight that high uncertainties in the results mean the possibility of heavier rain should not be ruled out. Like many Global South countries, Colombia and Venezuela are highly vulnerable to climate change, but their complex tropical climates are severely under-researched. 'A core aim of World Weather Attribution is to improve understanding of extreme weather in Global South countries,' says Dr Mariam Zachariah, research associate at the Centre for Environmental Policy, Imperial College London. 'Many have tropical climates, which are inherently difficult to study – a combination of mountains, coasts, rainforests and complex weather systems means rainfall is varied, intense and challenging to capture in climate models. 'Unfortunately, many countries with tropical climates have limited capacity to do climate science, meaning we don't have a good understanding of how they are being affected by climate change.' Did climate change make heavy rainfall worse in Colombia and Venezuela? In late June, intense rainfall swept across Colombia and Venezuela, causing widespread flooding and deadly landslides. Near Medellín in Colombia, a landslide buried homes and killed 27 people. In Venezuela, overflowing rivers ruined homes, wiped out crops and displaced thousands of people. To try and work out the role climate change played in this heavy rain, scientists looked at rainfall over two regions: the Colombian Andes and the Venezuelan Llanos. Historical data showed that neither event was particularly rare. In today's climate with 1.3°C of warming, the three months of rainfall in Colombia can be expected every ten years on average, while in Venezuela, similar five-day spells of heavy rain can be expected every three years. The study also found a drying trend with seasonal rainfall in Colombia, now 12 per cent less likely and less intense, while the chance of heavy rainfall over Venezuela was 9 per cent lower. Climate models also showed a drying trend in Colombia, but that was less clear in Venezuela. There were high uncertainties in the global data sets and models that the researchers looked at. Both Colombia and Venezuela have complex tropical climates, and they say the possibility of heavier rain shouldn't be ruled out. The Intergovernmental Panel on Climate Change projects a range of changes in rainfall in the region - but that prediction also has low confidence. Why are weather attribution studies in the Global South often inconclusive? World Weather Attribution says high uncertainty is typical in rainfall studies of Global South countries. Dr Zachariah points to another recent study on deadly floods in the Democratic Republic of Congo earlier this year, which also returned inconclusive results. The DRC is a developing country with a tropical climate. Historically, climate science has focused on wealthier countries, making data sets and models less accurate for places like these. Latin America is one of the most understudied regions in the world – this analysis is the first attribution study on a weather event in Venezuela and just the third for Colombia. 'Yet again, we've studied an extreme rainfall event in a Global South country and come up with unclear results,' explains Dr Joyce Kimutai, research associate at the Centre for Environmental Policy, Imperial College London. 'This is a scientific injustice.' Dr Kimutai emphasises that rich countries, which have contributed the most to global warming, are able to invest in research to understand how they will be affected by changing weather extremes. Poor countries, which have contributed the least but are the most vulnerable, have limited funds for climate research. 'This reduces their ability to understand what the future might bring and how they should prepare.' She adds that Latin America, the Caribbean and Africa need more extreme weather attribution studies. But the global data sets and climate models they use for these studies often perform poorly in these regions. 'Investing in weather stations and climate science will help. That money really should come from rich countries.' 'More science will save lives' While landslides and flash floods are common in both countries, the expansion of informal communities on hillsides is increasing the risk of disaster, the study highlights. And, while the landslide in Colombia was not extreme by historical standards, it still led to a significant loss of life. Researchers say many people living in these areas have been displaced by past disasters or conflicts and are moving closer to cities to search for better job opportunities. The experts add that adaptation efforts such as early warning systems and forest conservation can be cost-effective ways to reduce risks. 'Extreme weather is non-stop in Colombia and Venezuela. One year we face devastating flash floods; the next, severe droughts and wildfires,' says Professor Paola A. Arias, Professor at the Universidad of Antioquia in Colombia. 'It doesn't take much for a weather event to become a disaster because many people are already vulnerable. The late June downpours weren't especially unusual, however, they still triggered a landslide that killed 27 people.' Professor Arias adds that, while it's unclear if climate change increased rainfall in this case, it's almost certainly increasing the risk of drought, heatwaves and wildfires in both countries. 'We urgently need more investment in climate science to understand shifting risks and prepare for what's ahead. More science will save lives.'
Malay Mail
30-05-2025
- Health
- Malay Mail
Heatwaves getting worse? Scientists say answer is to cut out fossil fuels, fast
ISTANBUL, May 31 — Human-driven climate change added an average of 30 extra days of extreme heat over the past year for nearly half of the world's population, according to a new report released Friday ahead of Heat Action Day on June 2. The study, conducted by scientists from World Weather Attribution (WWA), Climate Central, and the Red Cross Red Crescent Climate Centre, emphasises the growing risks posed by heat waves as global fossil fuel use continues, Anadolu Ajansi (AA) reported. Between May 2024 and May 2025, some four billion people, about half of the global population, faced at least 30 additional days of extreme heat, defined as temperatures hotter than 90 per cent of historical observations for their regions, compared to a world without climate change. The researchers also found that climate change increased the number of extreme heat days by at least twofold in 195 countries and territories. All 67 major heat events recorded in the last year were exacerbated by human-caused climate change. 'This study needs to be taken as another stark warning. Climate change is here, and it kills,' said Friederike Otto, co-lead of WWA and senior lecturer at Imperial College London. 'We know exactly how to stop heat waves from getting worse: restructure our energy systems to be more efficient and based on renewables, not fossil fuels.' Mariam Zachariah, a researcher at Imperial College London, described the results as 'staggering,' noting that frequent, intense heat spells are linked to widespread impacts, including heat illnesses, deaths, crop losses, lowered productivity, and transport disruptions. Roop Singh, head of Urban and Attribution at the Red Cross Red Crescent Climate Centre, emphasised the urgent need to scale up responses. 'We need better early warning systems, heat action plans, and long-term urban planning to meet the rising challenge,' Singh said. Vice President for Science at Climate Central Kristina Dahl stressed that heat is the deadliest consequence of climate change. 'There is no place on Earth untouched by climate change, and we have the science to quantify how fossil fuel emissions are reshaping our daily temperatures and putting billions at risk,' she said. The report calls for governments to strengthen heat action plans, increase monitoring and reporting of heat impacts, and prioritise long-term adaptation strategies. — Bernama-Anadolu
Euronews
30-05-2025
- Science
- Euronews
Climate change drove heat extremes in 195 countries last year
Human-caused climate change added an average of 30 days of extreme heat for about half of the world's population over the past year, according to a new study. That amounts to four billion people exposed to prolonged, dangerous temperatures. And the findings single out fossil fuel emissions as the cause of the blistering heat. The study, published ahead of Heat Action Day on 2 June, comes from a collaborative attribution analysis by World Weather Attribution, Climate Central and the Red Cross Red Cross Climate Centre. Researchers examined temperature data from 247 countries and territories between May 2024 and May 2025 and found that, in 195 of them, climate change at least doubled the number of days classified as 'extreme heat.' 'This study needs to be taken as another stark warning. Climate change is here, and it kills,' says Dr Friederike Otto of Imperial College London and World Weather Attribution (WWA). To understand the influence of climate change, scientists first defined 'extreme heat' as days when temperatures exceeded the 90th percentile of the averages between 1991 and 2020. In other words, the hottest 10 per cent of days during that period. Then they tallied how many such days occurred in each country between May 2024 and May 2025. Next, they used climate models to simulate a world without human-induced warming. By comparing both sets of data, they were able to quantify just how many additional extreme heat days could be attributed directly to climate change. The difference was staggering. In many parts of the world, global warming didn't just increase temperatures. It made once-rare heatwaves a near-daily occurrence. Aruba, for example, suffered 187 days of extreme heat in the past year. Without climate change, the island's population would have endured just 45 such days. Researchers identified 67 extreme heat events globally last year. They focused on four: Central Asia in March 2025, South Sudan in February 2025, Mexico, the US and Central America in June 2024 and the Mediterranean in July 2024. In every case, they found that climate change made the back-breaking heat more likely or more severe. 'Climate change is clearly challenging life on every continent,' says Dr Mariam Zachariah, a WWA researcher at the Centre for Environmental Policy at Imperial College London. 'These frequent, intense spells of hot temperatures are associated with a huge range of impacts, including heat illness, deaths, pressure on health systems, crop losses, lowered productivity and transport disruptions,' she adds. Europe is among the regions already suffering the most visible and deadly consequences of human-induced climate change. Last summer, wildfires and heatwaves swept through southern Europe. Scientists warned that climate change made them three times more likely. Greece endured deadly Juneheatwaves triggered by climate change that strained hospitals and caused mass evacuations from tourist destinations. Over the past two summers, extreme heat has led authorities to close the Acropolis – the country's most-visited site, attracting millions each year – during the hottest hours of the day. In July,southeastern Europe experienced its longest heatwave on record, lasting 13 consecutive days and affecting 55 per cent of the region. Prolonged heat in Spain, France and Italy caused transport disruptions, strained power grids and forced schools to shut early. In total, the record-breaking heat is thought to have killed more than47,000 people in Europe in 2024. The outlook continues to be grim, too. Climate experts project23 million additional temperature-related deaths in Europe by 2099 if warming continues unchecked. 'The evidence for the link between climate change and heatwaves is undeniable,' says Roop Singh, head of urban and attribution at the Red Cross Red Crescent Climate Centre. 'Through our interactions, we know that people are feeling the rise in heat, but they don't always understand that it's being driven by climate change, and that it will continue to get much, much worse.' Despite the mounting pressure it places on global populations, heat remains one of the most underappreciated consequences of the climate crisis. Climate change was found to have caused41 additional days of dangerous heat in 2024, unleashing what researchers called 'unrelenting suffering' across the globe. That suffering isn't always exposure to extreme heat has been linked to accelerated ageing and damage at the cellular level. For the next generation, the picture is even more alarming. A recent study estimated that83 per cent of five-year-olds will live through far more frequent and intense heatwaves than any previous generation. 'There is no place on Earth untouched by climate change – and heat is its most deadly consequence,' said Dr Kristina Dahl, vice president for science at Climate Central. 'We have the science to quantify how fossil fuel emissions are reshaping our daily temperatures – and putting billions at risk.' The landslide that buried most of a Swiss village this week is focusing renewed attention on the role of global warming in glacier collapses around the world and the increasing dangers. How glaciers collapse - from the Alps and Andes to the Himalayas and Antarctica - can differ, scientists say. But in almost every instance, climate change is playing a role. In Switzerland, the mountainside gave way Wednesday near the village of Blatten, in the southern Lötschental valley, because the rock face above the Birch Glacier had become unstable when mountain permafrost melted, causing debris to fall and cover the glacier in recent years, said Martin Truffer, a physics professor at the University of Alaska Fairbanks who studies how glaciers move. While the debris insulated the glacier and slowed melting, its weight caused the ice to begin moving - which accelerated dramatically a few weeks ago. Authorities ordered the evacuation of about 300 people, as well as all livestock, from the village in recent days, 'when it became clear that there's a whole mountainside that's about to collapse,' said Truffer, who is from Switzerland. Lakes that form at the base of glaciers as they melt and retreat also sometimes burst, often with catastrophic results. Water can even lift an entire glacier, allowing it to drain, said Truffer, adding that Alaska's capital of Juneau has flooded in recent years because a lake forms every year on a rapidly retreating glacier and eventually bursts. In 2022, an apartment building-sized chunk of the Marmolada glacier in Italy's Dolomite mountains detached during a summer heat wave, sending an avalanche of debris down the popular summer hiking destination, killing 11. A glacier in Tibet's Aru mountain range suddenly collapsed in 2016, killing nine people and their livestock, followed a few months later by the collapse of another glacier. There also have been collapses in Peru, including one in 2006 that caused a mini tsunami; most recently, a glacial lagoon overflowed in April, triggering a landslide that killed two. 'It's amazing sometimes how rapidly they can collapse,' said Lonnie Thompson, a glacier expert at the Ohio State University. 'The instability of these glaciers is a real and growing problem, and there are thousands and thousands of people that are at risk.' Scientists say melting glaciers will raise sea levels for decades, but the loss of inland glaciers also acutely affects those living nearby who rely on them for water for drinking water and agriculture. Scientists say greenhouse gases from the burning of fossil fuels such as coal have already locked in enough global warming to doom many of the world's glaciers - which already have retreated significantly. For example, glaciers in the Alps have lost 50 per cent of their area since 1950, and the rate at which ice is being lost has been accelerating, with 'projections ... that all the glaciers in the Alps could be gone in this century,' Thompson said. Switzerland, which has the most glaciers of any country in Europe, saw 4 per cent of its total glacier volume disappear in 2023, the second-biggest decline in a single year after a 6 per cent drop in 2022. A 2023 study found that Peru has lost more than half of its glacier surface in the last six decades, and 175 glaciers disappeared due to climate change between 2016 and 2020, mostly due to the increase in the average global temperature. A study published Thursday in Science said that even if global temperatures stabilized at their current level, 40 per cent of the world's glaciers still would be lost. But if warming were limited to 1.5 degrees Celsius - the long-term warming limit since the late 1800s called for by the 2015 Paris climate agreement - twice as much glacier ice could be preserved than would be otherwise. Even so, many areas will become ice-free no matter what, Truffer, the University of Alaska expert. 'There's places in Alaska where we've shown that it doesn't take any more global warming,' for them to disappear, Truffer said. 'The reason some ... (still) exist is simply because it takes a certain amount of time for them to melt. But the climate is already such that they're screwed.'
