Climate
Climate Change, Not El Niño, Is Driving Global Coral Bleaching, New Study Finds
Human-caused climate change—not El Niño—is driving global coral bleaching, according to a new Oceanography study that warns reefs face escalating risks.
Nearly every global coral bleaching event over the past four decades would not have occurred without human-caused climate change, according to a new study published in Oceanography. Researchers found that while El Niño can intensify ocean warming, fossil fuel-driven climate change has been the decisive factor behind mass bleaching events since 1998. The findings suggest rising global temperatures—not natural climate variability—are now the dominant threat to coral reefs and the millions of people who depend on them.
Nearly every mass coral bleaching event of the past four decades would not have happened without human-caused climate change, according to new research published in the journal Oceanography — a finding that upends the common assumption that El Niño is the primary trigger behind the world’s worst reef die-offs.
The study, led by Climate Central, examined the four global bleaching events recorded since 1998 — in 1998, 2010, 2014–2017, and 2018–2025 — periods that have typically been associated with El Niño’s warming influence on the Pacific Ocean. Researchers found that fossil fuel-driven ocean heat, not the natural climate cycle, was the fundamental force behind the bleaching and coral mortality in each case.
Climate Change Is Driving Global Coral Bleaching,
Scientists used a multi-model extreme event attribution method — a technique that isolates how much of an observed climate event can be traced to human-caused warming versus natural variability — to assess climate change’s influence on sea surface temperatures. They then layered those results onto the coral bleaching risk model developed by NOAA’s Coral Reef Watch program to calculate how much of the observed bleaching risk was attributable to each factor.
The results were stark for the most recent and most severe event. During the 2018–2025 bleaching event, the analysis found there would have been essentially no coral bleaching — and certainly no global-scale event — in a world without human-caused climate change. Of the 71 regions where bleaching was observed during that period, only one would have faced even a moderate bleaching risk absent climate change. Researchers found similar results across all of the other three global events: in each case, climate change was necessary to push ocean temperatures over the threshold at which bleaching occurs.
“Our study shows that without climate change, coral bleaching would be a rare and isolated event, and global mass coral bleaching simply would not occur,” said Andrew Pershing, Chief Program Officer at Climate Central and the study’s lead author. “Millions of people and entire countries rely on healthy coral reefs for livelihoods and food security. But our emissions of carbon pollution are causing increasingly widespread damage and death to these vital and vibrant ecosystems. Without immediate emissions reduction, coral reefs as we know them will disappear.”
What it means for the El Niño underway now
Using the same methodology, the researchers also modeled bleaching risk for the El Niño event currently underway, which began in 2026. They project that while natural El Niño-driven warming could produce low levels of bleaching risk in a handful of regions, human-caused climate change is likely to drive bleaching more broadly across the globe — with the southern Caribbean, the Central and South American coasts, and the coasts of eastern Asia identified as particular hotspots.
The researchers argue the finding matters because public discussion of bleaching events tends to focus on El Niño rather than the underlying warming trend. That framing, they say, is likely to become increasingly inaccurate: under current warming rates, the study concludes that rising temperatures driven by human-caused climate change will outweigh El Niño’s contribution in every coral-containing region on Earth by 2028.
A narrowing window for reefs already under strain
The paper adds to a growing body of evidence that coral reefs, despite some documented capacity to adapt to warmer conditions, remain at escalating risk. Absent a reduction in carbon emissions, the study’s authors conclude, continued ocean warming raises the likelihood that reef ecosystems as they currently exist could disappear permanently.
Coral reefs cover a small fraction of the ocean floor but support an outsized share of marine life, and provide fisheries, coastal protection, and tourism revenue that hundreds of millions of people depend on directly.
Climate
From Fighting Water to Saving It: The Netherlands Faces a Growing Drought Challenge
A land built to keep water out is now struggling to keep enough of it in — forcing a world leader in water management to rethink its infrastructure
The Netherlands built its global reputation by keeping water out. Now, longer dry spells and intensifying heatwaves are forcing the country to confront a very different problem: how to keep enough fresh water in the landscape. From greenhouse agriculture to homes built on wooden foundation piles, the Netherlands drought challenge is exposing the limits of infrastructure designed primarily for flood protection.
When people think of the Netherlands, the images that come to mind are windmills, tulip fields and the great sea walls that have kept the ocean at bay for centuries. The Dutch built their reputation, and much of their nation, on mastering water — pumping it away, holding it back, and reclaiming land from the sea to build a prosperous country on ground that, by rights, shouldn’t exist. Yet beneath that carefully engineered landscape, the Netherlands is now facing an unfamiliar problem: it is running out of fresh water.
As repeated summer heatwaves sweep across Western Europe, Dutch water authorities say they have reached the limit of what engineering can do. In several regions, officials have exhausted every standard measure available to them and are left with what amounts to a last resort — waiting, and hoping, for rain.
Netherlands Drought Challenge: From Floods to Water Scarcity
To understand how a country famous for its rainfall and rivers has arrived at this point, it helps to look at how the land itself was designed. For generations, the Dutch water system had one job: get excess water out to sea as fast as possible, to prevent flooding. That same efficiency has become a liability as weather patterns shift towards longer dry spells and more intense heat. The pressure peaks in late summer, when temperatures regularly cross 35°C and water evaporates faster than rainfall can replace it.
The consequences of shrinking water reserves go well beyond the daily weather report. They are already reaching into the economy, and into the foundations — quite literally — of Dutch homes.
Thousands of historic Dutch houses stand on wooden foundation piles. When groundwater levels drop, those piles are exposed to air and begin to rot. On clay and peat soils, the ground shrinks unevenly, pulling foundations down and cracking brick walls
Economic Strain and Sinking Homes
In Westland, the heart of Dutch greenhouse horticulture, the Delfland water authority has banned growers from drawing irrigation water from local ditches and canals — the first such ban in its history. According to the growers’ umbrella body Glastuinbouw Nederland, the ban affects around 150 commercial growers, with potential damages running as high as €150 million.
At the same time, a quieter crisis is unfolding beneath people’s homes. Thousands of historic Dutch houses stand on wooden foundation piles. When groundwater levels drop, those piles are exposed to air and begin to rot. On clay and peat soils, the ground shrinks unevenly, pulling foundations down and cracking brick walls. The Council for the Living Environment and Infrastructure estimates that close to half a million buildings across the country could show foundation damage by 2035, with repair costs reaching as much as €54 billion.
From Water Battle to Water Sponge
This reality is forcing a fundamental shift in how the Netherlands manages its resources. For centuries, Dutch policy was simple: fight the water, and push it away. Today, water authorities are engaged in a delicate balancing act, trying to save every drop using canal locks and storage basins. But holding onto existing water can only do so much once the rain stops altogether.
Long-term resilience will require redesigning the landscape itself. Rather than treating rainwater as a threat to be flushed out to sea, experts increasingly argue that the Netherlands needs to function more like a giant sponge — capturing heavy winter rain and storing it safely to survive the dry summer months that are becoming the norm.
A Lesson Beyond Borders
What is unfolding in the Netherlands carries a lesson well beyond it. If a nation this experienced in water engineering is struggling to keep pace with a changing climate, it says something about how quickly conditions can outrun even the most sophisticated infrastructure. As riverbeds stay low and the dry spells drag on, the Dutch find themselves in an unfamiliar position for a country built on water: waiting for the skies to open.
Climate
Environmental Literacy, Not Tree Planting, Is What India’s Schools Need
Awareness is not the same as literacy — and India’s classrooms are still teaching the former
Planting trees and organising awareness campaigns are valuable, but they cannot replace environmental literacy. As climate change increasingly shapes everyday life, India’s schools must teach students how environmental systems, public policy and sustainability are interconnected.
Every year, schools across India mark World Environment Day with the same rituals. Children plant saplings, make posters, join cleanliness drives, and pledge to “save the environment.” A photograph is taken, a few speeches are made, and the saplings are watered for a week or two before the event winds down and environmental education slips back to the margins of the curriculum. There is nothing wrong with planting trees. The concern is what happens when tree-planting, poster-making and occasional awareness drives become the whole of environmental education: children end up with a dangerously thin understanding of the environmental forces that already govern their lives.
India’s environmental problems are no longer confined to the classroom or the textbook. Heatwaves have thrown school timetables out of kilter. Air pollution affects children’s health and their ability to concentrate. Floods and cyclones disrupt attendance and damage school infrastructure. Water shortages are a recurring reality in many parts of the country, and waste management, plastic pollution, groundwater depletion and biodiversity loss are becoming questions of everyday survival rather than abstract concerns. Yet much of environmental education still treats the environment as something outside the classroom, and environmental protection as an occasional act of cleaning or conservation. The problem isn’t that Indian children don’t know about trees. It’s that they are rarely taught why environmental crises happen, who pays the price for them, and what other choices communities could make.
Why Environmental Literacy Matters
India has a long history of institutional efforts on environmental education. Supreme Court rulings in the 1990s pushed environmental education into schools, and the National Curriculum Framework, along with subsequent policy measures, tried to weave environmental topics into the curriculum. The National Education Policy (NEP) 2020 places considerable emphasis on environmental awareness, sustainable development and responsible citizenship. On paper, the direction looks promising. In the classroom, that intent rarely survives translation.
A student may be told to conserve electricity, but is anyone explaining where India’s electricity comes from, why coal still dominates the grid, how renewable energy is expanding, and what trade-offs come with each alternative?
A child might learn that forests matter for ecological balance, but is anyone teaching them why the trees are being cut, who owns the forest land, what happens to the communities living in or around forests, how infrastructure projects reshape ecosystems, or how climate change itself is accelerating deforestation? A student may be told to conserve electricity, but is anyone explaining where India’s electricity comes from, why coal still dominates the grid, how renewable energy is expanding, and what trade-offs come with each alternative? A pupil may be advised not to waste water, but do they understand groundwater depletion, unequal access to water, the weaknesses in urban infrastructure, or the politics of sharing rivers between states?
These are fundamentally different levels of learning. The first produces awareness. The second produces environmental literacy. India needs far more of the latter.
The Environment Is Not Only a Question of Individual Behaviour
One of the deepest weaknesses of conventional environmental education is its tendency to place almost the entire burden on the individual: turn off the lights, carry a cloth bag, don’t litter, plant a tree, use less water. These are worthwhile habits. But taken alone, they carry a quiet suggestion — that environmental destruction is essentially a matter of personal carelessness. Climate change, pollution and ecological collapse are not happening because people forget to switch off a fan or reuse a plastic bag.
They are the product of energy systems, industrial production, urban design, transport networks, agricultural practices, consumption patterns and public policy choices. When environmental education stops at individual behaviour, students may grow into conscientious consumers while remaining unaware of the institutional and political processes that actually shape environmental outcomes. They should also be taught to ask who is responsible for emissions, and why a project is sited where it is. That shift — from moral instruction to civic awareness — is the one Indian environmental education still largely has not made.
Climate Change Is Already in the Classroom
The strongest argument for rethinking environmental education is that climate change is no longer a distant subject for Indian schoolchildren — it is already shaping their school experience. Extreme heat makes classrooms uncomfortable and undermines concentration. Floods and cyclones damage school infrastructure and disrupt attendance. Air pollution curtails outdoor activity. Water scarcity affects sanitation facilities, with a disproportionate impact on adolescent girls.
These effects are not distributed evenly. A private school with air conditioning, backup power and a reliable water supply absorbs climate stress very differently from an under-resourced government school. Climate change, in other words, is not only an environmental issue — it is also a question of educational inequality. A child sitting through a heatwave in a poorly ventilated classroom experiences climate change in fundamentally different terms from a child in a climate-controlled one, yet few environmental education programmes address that disparity directly. They should. Climate literacy needs to teach children that environmental issues are inseparable from class, geography, gender, occupation and access to infrastructure.
From ‘Save the Planet’ to Environmental Justice
Another limitation lies in how environmental issues are framed. Students are told they must “save the planet.” But the planet will endure regardless. The more urgent question is what kind of civilisation humanity will be able to inhabit as environmental pressures mount — and that is where environmental justice comes in.
India’s renewable energy transition makes this complexity visible. Solar and wind power are essential to reducing dependence on fossil fuels, but large-scale projects can also mean land acquisition, damage to agricultural livelihoods, and conflict with local communities. Protecting biodiversity matters, but so do the rights of people living around protected areas. Electric vehicles cut tailpipe emissions, but their batteries depend on mineral mining with its own environmental and social costs. Recycling eases pressure on landfills, but informal waste collectors often work in hazardous, unregulated conditions.
None of this is an argument against environmental action. It is an argument for teaching students how environmental systems actually work, contradictions included. A mature curriculum should embrace that complexity rather than flatten it.

Teachers Need Support, Not Just Demands
None of this is possible if teachers are left to carry the burden alone. Environmental education, where it exists, is often exam-driven, squeezed for time, and layered on top of an already heavy workload. Many teachers have no specialised training in climate science or environmental policy. Improving environmental education is, in large part, a question of improving teacher preparation and giving teachers the tools to connect environmental issues to subjects they already teach: geography can examine groundwater depletion, economics can study the cost of pollution, civics can look at environmental regulation, mathematics can work with climate data, history can trace industrialisation and land-use change, and language classes can practise environmental journalism and writing. Environmental education does not need a separate subject. It needs a different way of teaching the subjects that already exist.
The Classroom as a Site of Inquiry
Some of the most valuable environmental learning may not come from lectures at all. Schools can double as sites of inquiry. Students can take temperature readings in their own classrooms and study local heat patterns, check air quality where they live, map household water use, conduct waste audits, track the loss of local biodiversity, or examine power consumption and the potential for renewables. They can trace where their school’s waste actually goes. These exercises build evidence-based reasoning in a way no poster campaign can, developing skills in observation, questioning and analysis that are essential to understanding environmental issues.
Beyond Symbolic Environmentalism
Finally, what is needed is a cultural shift, not another annual ritual. Environmental education should be more than a photograph of children clutching saplings. A planted tree is visible; the systems that actually determine environmental outcomes — urban design, energy generation, water governance, waste management, industrial regulation, the distribution of climate risk — are not, and children need to understand them regardless.
India is raising a generation that will have to navigate hotter cities, strained water systems, shifting coastlines and difficult development choices. Telling children to plant trees isn’t wrong. It simply isn’t enough. The goal of environmental education should not be young people who appreciate the value of a tree, but citizens who understand how societies shape the environment — and how the environment, in turn, shapes society. That is the real difference between symbolic awareness and meaningful education.
Climate
How Assam’s Recurrent Floods Are Becoming an Economic Burden
Assam’s recurrent floods are creating a growing economic burden, from ₹200 crore in estimated annual losses to 4.27 lakh hectares of land lost to erosion since 1950. As rainfall patterns shift and compound flooding intensifies, the state faces rising risks to livelihoods, infrastructure and development.
Floods are a recurring part of life in Assam. Every monsoon, the Brahmaputra and its tributaries spill into the state’s floodplains, disrupting agriculture, damaging infrastructure and forcing communities to move. But each flood leaves behind more than waterlogged fields and damaged roads. It also leaves an economic bill.
On average, floods inundate 9.31 lakh hectares of Assam every year, according to the state government. Nearly 40% of the state’s land area is flood-prone, while average annual flood losses are estimated at around INR 200 crore. Riverbank erosion adds a more permanent cost. According to report by Climate Central, Assam has lost nearly 4.27 lakh hectares of land since 1950, equivalent to about 7.4% of its geographical area.
The cost does not end when the water recedes. Floods repeatedly disrupt agriculture, tea plantations, fisheries, transport and livelihoods. When a river changes course and takes away farmland, the loss can last for generations. Homes disappear, productive land shrinks and families are forced to start again elsewhere.
The scale of displacement shows how closely the human and economic costs are linked. In 2024, floods in Assam triggered an estimated 2.5 million internal displacements, accounting for nearly half of all disaster-related displacements recorded in India that year.
For a state that has learned to live with floods, the bigger challenge is now managing the repeated economic shocks they create.
When Floods Become Compound
Assam’s floods are rarely the result of one factor alone. Increasingly, several processes can come together to push rivers beyond their limits. Scientists describe this as compound flooding—when multiple sources contribute to flooding at the same time.
Heavy rainfall over Assam can coincide with intense precipitation upstream in Arunachal Pradesh, Bhutan and Tibet. Snow and glacier melt in the eastern Himalayas add seasonal runoff, while swollen tributaries, landslides and riverbank erosion can make the situation worse. The result can be higher flood peaks and longer periods of inundation.
The economic consequences can also multiply. Heavy rain may destroy crops, while rising river levels erode farmland and damage roads. A washed-out bridge can disrupt the movement of food and goods. A flooded market can stop local businesses from operating. For families dependent on daily wages, even a few days without work can mean lost income. In other words, the flood may last days, but its economic effects can last much longer.

A River that Keeps Reshaping the Economy
The Brahmaputra basin stretches across China, Bhutan, India and Bangladesh, covering approximately 650,000 square kilometres. Once the river enters India, it travels for about 710 kilometres through the Assam Valley.
It is a river in constant motion. The Brahmaputra carries huge quantities of sediment from the Himalayas, creating braided channels, shifting sandbars and constantly changing riverbanks.
For Assam, this makes flooding different from a short-lived disaster. The river does not simply cover the land; it can redraw the map.
Assam has lost approximately 4.27 lakh hectares of land to erosion since 1950. The loss is not merely geographical. Farmland disappears, homes are displaced and established settlements can be cut off or forced to move. With the land goes the economic activity that depended on it.
Climate projections suggest that these pressures could intensify. The Assam State Action Plan on Climate Change projects a 5–38% increase in extreme rainfall events and more than a 25% rise in flood events under future climate scenarios. Models also project around a 13% increase in the Brahmaputra’s annual streamflow, while sediment loads could rise by nearly 40% by the end of the century.
If these projections materialise, Assam could face more frequent flooding alongside growing pressure on land, infrastructure and livelihoods.
The Himalayan Connection
The economic risks in Assam begin much farther upstream. The Hindu Kush Himalayan Assessment projects that even if global warming is limited to 1.5°C, at least one-third of the region’s glacier volume could disappear by 2100. Under higher-emission scenarios, glacier losses could exceed 50–65%.
In the short term, warmer temperatures can accelerate snow and glacier melt, increasing runoff. Over time, continued glacier retreat could alter the timing and volume of water entering the river system. Rainfall patterns are changing too. A systematic review cited in the document points to a possible shift in peak rainfall from July to August, along with increasing post-monsoon rainfall and declining pre-monsoon rainfall.
That matters because when rain falls can be as important as how much falls. More intense rainfall can produce sharper flood peaks and leave less time for water to drain.
As Mahesh Palawat, Vice President–Meteorology and Climate Change at Skymet Weather, notes, increasing rainfall variability and shifting monsoon behaviour are making floods less predictable. For Assam, unpredictability has an economic cost of its own. Farmers need to decide when to sow and harvest. Businesses depend on functioning roads and transport networks. Governments have to plan infrastructure that may need to withstand increasingly uncertain conditions.
The Cost of Exposure
Climate change is only part of the picture. Deforestation, urbanisation and unplanned land-use changes can increase runoff and reduce the landscape’s ability to hold water. Development in flood-prone areas also puts more homes, businesses and infrastructure in harm’s way.
The vulnerability is particularly high in low-lying floodplain and char areas, where communities face both flooding and erosion. Repeated displacement can mean losing homes, productive assets and livelihoods more than once. This is why the economic burden of flooding cannot be measured only by the value of buildings or crops damaged during a flood.
It also includes lost working days, disrupted supply chains, damaged crops, interrupted transport, relocation costs and public spending on repairs and recovery. The estimated INR 200 crore in average annual flood losses therefore represents only part of the wider economic burden.
A Future of More Frequent Shocks
The projections point to a difficult future. Hydrological simulations cited in the document suggest that a flood that currently occurs once every 10 years could occur once every two years by 2080 under high-emission scenarios.
This does not mean every future flood will follow that pattern. But it shows how sharply flood frequency could change. And that raises an economic question that Assam will increasingly have to confront: How often can communities, businesses and governments afford to rebuild?
If floods become more frequent, recovery from one event could overlap with preparation for the next. Money spent repairing roads, restoring farmland and rebuilding homes would have to compete with investments needed for long-term development. The cost of doing nothing could therefore extend well beyond the next flood season.
Reducing the Cost of Living With Floods
Assam cannot stop the Brahmaputra from flooding. But it can reduce the damage and, in turn, reduce the economic cost. That means improving upstream observations and early-warning systems, strengthening data sharing across the Brahmaputra basin and designing infrastructure for future climate risks. Floodplain planning, erosion management and ecosystem protection also need to become part of long-term development planning rather than being treated only as disaster-response measures.
Better forecasts can give communities and businesses more time to move livestock, crops and equipment. Better risk maps can help determine where critical infrastructure should, and should not be built. Protecting natural flood buffers can also help slow runoff and reduce exposure.
As Dr Akshay Deoras, Research Scientist at the National Centre for Atmospheric Science, University of Reading, argues, preparing for Assam’s future floods means accounting for changing rainfall patterns, not simply the total amount of rainfall. The Brahmaputra will continue to shape Assam. Floods will remain part of the state’s geography.
The challenge is to ensure that every flood does not also become another economic setback, another loss of land, another disrupted livelihood, another damaged road and another bill to pay. Living with the Brahmaputra may be unavoidable. Making that relationship increasingly unaffordable is not.
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