Climate change fueled a punishing year of extreme weather in 2025 that fell hardest on poorer communities, even as a cooling La Niña pattern took hold, according to a new assessment by World Weather Attribution, an international group of climate scientists.
The annual report found that 2025 ranked among the three hottest years ever recorded, a sign of how far human-caused warming has pushed baseline temperatures. That backdrop turbocharged heatwaves, droughts, storms and wildfires across continents, widening a stark inequality in who suffers most from climate risk and who benefits least from protection and recovery.
- Advertisement -
Scientists warned that the world is edging closer to the long-term breach of 1.5C of warming above preindustrial levels, a threshold tied to faster sea-level rise, escalating climate hazards and greater odds of irreversible tipping points. For low-income and marginalized populations already grappling with chronic vulnerabilities, the report said the year’s extremes pushed many closer to the “limit of adaptation,” the point at which measures to reduce harm are no longer sufficient.
“Each year, the risks of climate change become less hypothetical and more brutal reality,” said Friederike Otto, a climate scientist at Imperial College London and a WWA co-founder. “Our report shows that despite efforts to cut carbon emissions, they have fallen short in preventing global temperature rise and the worst impacts. Decision-makers must face the reality that their continued reliance on fossil fuels is costing lives, billions in economic losses, and causing irreversible damage to communities worldwide.”
WWA identified 157 extreme weather events in 2025 that met criteria for humanitarian impact. Floods and heatwaves were the most frequent, with 49 events each. They were followed by storms (38), wildfires (11), droughts (seven) and cold spells (three). Of the 22 events scrutinized in depth through attribution science—methods that test how climate change alters the likelihood or intensity of extreme events—17 were found to be made more likely or more severe by human-caused warming. Five showed inconclusive results, often because of sparse weather data and limitations in regional climate models.
The science team also reanalyzed six extreme heat episodes since the 2015 Paris Agreement, finding that some of today’s heat events are up to 10 times more likely than a decade ago. In 2025 alone, WWA linked human-induced warming to intensified heatwaves in South Sudan, Burkina Faso, Norway, Sweden, Mexico, Argentina and England. While most heat-related deaths go uncounted, one study cited in the report estimated 24,400 deaths from a single European summer heatwave this year.
The findings underscore how extreme heat has fast become a defining hazard of the climate crisis. Daytime highs and nighttime temperatures that fail to offer relief strain health systems, reduce labor productivity, and amplify risks for the elderly, children and people with preexisting conditions. In many places, those most exposed—outdoor workers, informal settlements, and households without cooling—have the least power to avoid or buffer the danger.
The report also points to a volatile storm year. Tropical cyclones and severe storms were among 2025’s deadliest events, including several that struck Asia and Southeast Asia in rapid succession, killing more than 1,700 people and causing billions of dollars in damage. That cluster of disasters arrived just weeks after Hurricane Melissa carved a path of destruction in Jamaica, testing recovery systems that WWA said are already stretched by compounding shocks.
Far from coastal zones, many regions suffered prolonged dryness. Central Africa, western Australia, central Brazil, Canada and large parts of the Middle East experienced some of their driest years on record. The report links these droughts to water shortages, crop failures and worsened wildfire conditions, often creating cascading impacts: when soils are parched and vegetation is stressed, fires spread faster and burn hotter, and communities have fewer resources to cope.
WWA’s analysis found that climate change significantly increased the likelihood of major wildfires such as those in Palisades, Los Angeles, and in southern Spain. Those blazes not only destroyed homes and infrastructure but also degraded air quality over large regions, compounding health risks for vulnerable groups.
Equity threads through the report. In 2025, extreme weather consistently hit those with the least capacity to prepare, evacuate or rebuild, the scientists said. The inequity extends to climate science itself: many countries in the Global South still lack robust datasets and tailored models, which hinders precise attribution and leaves decision-makers with less actionable information even as they face the greatest hazards.
WWA emphasized that both adaptation and mitigation are essential, but that the most effective way to head off worsening extremes is to cut planet-warming emissions quickly. Reducing reliance on fossil fuels, the authors said, is the clearest path to preventing deadlier impacts later this decade and beyond. At the same time, measures that reduce exposure—such as risk-informed urban planning, resilient infrastructure, and community-centered preparedness—can save lives now, though the report warned that escalating heat and compounding hazards are pushing many places toward the limits of what adaptation can achieve.
The data gaps are part of the problem, especially where public weather stations are sparse and early warning systems are underfunded. Better monitoring, open data and sustained investment in climate information services would sharpen risk forecasts and help tailor interventions to local conditions, WWA said. The authors cautioned that defunding climate information initiatives is a false economy in a world where each degree of warming translates into higher humanitarian and fiscal costs.
“This year we have also seen a slide into climate inaction, and the defunding of important climate information initiatives,” said Theodore Keeping, a researcher at Imperial College London. “In 2026, every country needs to do more to prepare for the escalating threat of extreme weather and to commit to the swift replacement of fossil fuels and avoid further devastation.”
The report arrives as policymakers weigh how to close the gap between existing emissions pledges and what climate science says is necessary to avoid breaching dangerous thresholds. The contrast between 2025’s heat and a La Niña year—typically associated with cooler global temperatures—illustrates the potency of the long-term warming trend now dominating the planet’s climate. Natural variability can no longer mask the signal.
WWA’s central message is blunt: without rapid, sustained cuts in fossil fuel use, the extremes of 2025 will not be outliers but previews. For communities already at the edge of coping, that trajectory means more lives at risk, more livelihoods lost and more hard-won development gains undone. With better data, stronger preparation and a decisive pivot away from fossil fuels, the scientists argue, the world can still blunt the worst impacts—but the window is closing.
By Abdiwahab Ahmed
Axadle Times international–Monitoring.
