Nearly 200 governments are converging on Belém, Brazil, for the COP30 UN climate summit – but the world’s second-largest emitter has effectively left its seat empty. President Donald Trump has declined to send any senior U.S. officials, even as scientists warn that the planet is almost certain to overshoot the 1.5°C warming limit within the next decade. Into that vacuum steps California: Governor Gavin Newsom and a high-level state delegation are pitching the Golden State as a stand-in for U.S. climate leadership, highlighting deep cuts in emissions alongside strong economic growth, and a web of international climate partnerships. At the same time, a new UNEP Emissions Gap report shows the world still heading toward a dangerous 2.3–2.8°C of warming this century, with Trump’s decision to quit the Paris agreement adding roughly 0.18°C to those projections. The message from Belém is brutally simple: while Washington walks away, every fraction of a degree now depends on whether others move faster.
In October, more than 100 countries were on the verge of approving the first global fee on greenhouse gases from cargo ships, a move that could have pushed a heavily polluting industry toward cleaner fuels. Instead, U.S. officials under President Donald Trump mounted an unusually aggressive pressure campaign, warning vulnerable nations that supporting the measure could cost them visas, trade access and even the right for their sailors to set foot in American ports, according to diplomats who took part in the talks and later described the tactics as bullying. After weeks of threats, the International Maritime Organization, the U.N. shipping regulator, voted 57–49 to delay the decision for a year, effectively stalling the deal just months after governments had celebrated a fragile compromise on maritime carbon pricing. Shipping already produces roughly 3 percent of global greenhouse gas emissions and could account for far more by mid-century if left unchecked, making the collapse of this effort a serious blow to hopes of keeping global warming close to 1.5 degrees Celsius.
As world leaders land in Belém for the COP30 climate summit, the world’s three largest polluters – China, the United States and India – are conspicuously missing from the opening leaders’ segment. Their absence overshadows Brazilian President Luiz Inácio Lula da Silva’s bold attempt to launch a massive Tropical Forests Forever Fund that would pay countries to keep their rainforests standing, even as Brazil itself still approves new oil exploration near the Amazon. Scientists warn that around 17% of the Amazon has already been destroyed, pushing the “lungs of the planet” dangerously close to an irreversible tipping point. Meanwhile, Indigenous leaders and youth activists are filling the streets and rivers with protests and flotillas, insisting that there is no time left for half-measures or political games. What happens – and what fails to happen – in Belém will echo far beyond the rainforest.
On the edge of the Amazon rainforest, world leaders are opening the COP30 climate summit under mounting pressure from protesters demanding real action instead of more speeches. Inside the heavily guarded venue in Belém, negotiators are debating how to keep global heating as close as possible to 1.5°C, even as UN scientists warn that current policies still point toward far more dangerous levels of warming. Outside, Indigenous leaders, youth movements and climate groups are marching, staging creative actions and delivering a “climate bill” that they say should be paid by fossil fuel companies, not ordinary people. With 2025 set to be among the hottest years ever recorded and the Amazon edging toward an irreversible tipping point, activists argue that what happens in Belém will echo far beyond Brazil’s borders.
A new study from Cornell University, published in the journal Nature Sustainability, maps how the AI boom could collide head-on with U.S. climate goals if left unchecked. The researchers find that, depending on how fast AI expands, American data centers could end up using as much water as about 10 million people and emitting as much carbon dioxide as 10 million cars every year, with impacts comparable to the entire state of New York’s energy and water demand. Where the servers are built matters enormously: the same AI workload can have several times higher emissions in one state than another. At the same time, a separate report from the Center for Biological Diversity warns that gas-powered data centers could swallow nearly half of the emissions space left for the U.S. power sector under 2035 climate targets. Together, the studies suggest a stark choice: act now to steer AI, or let it lock in a new fossil-fuel era.
Hurricane Melissa’s devastating landfall in the Caribbean was not just a natural disaster, but a storm supercharged by human-caused climate change, according to a new rapid scientific analysis. Researchers with the World Weather Attribution project estimate that global warming increased Melissa’s top wind speeds by around 7%, made rainfall near the eye 16% heavier, and made the hot, humid background conditions that fed the hurricane roughly six times more likely than in a pre-industrial climate. The Category 5 storm slammed into Jamaica on 28 October with sustained winds near 185 mph, then raked Cuba, Haiti and the Dominican Republic, tearing off roofs, smashing hospitals and roads, and helping drive at least dozens of deaths and billions of dollars in losses across the region. Scientists warn that Melissa is not a one-off freak event, but a stark preview of a future in which ever-warmer oceans and air push hurricanes beyond what many communities can withstand.
October 2025 was officially the planet’s third-warmest October on record – but that dry ranking hides how dangerous our new climate reality has become. Copernicus data show global surface air temperatures 1.55°C above pre-industrial levels and 0.70°C above the 1991–2020 average for the month, with 2025 almost certain to end as the second- or third-warmest year ever measured surface air temperature analysis and summary of Copernicus data. At the same time, a weak La Niña has already formed – yet global heat barely budged, underscoring the overwhelming influence of human-caused warming ENSO Diagnostic Discussion. Sea ice at both poles slumped near record lows, and heat records are falling in dozens of countries. UN climate agencies now warn that the “triple whammy” of extreme warmth in 2023, 2024 and 2025 risks triggering irreversible damage unless emissions fall sharply and immediately UN/WMO overview.
New climate research suggests that global warming could, over very long timescales, flip into a deep freeze instead of gently stabilising. Using an advanced Earth system model, scientists Dominik Hülse and Andy Ridgwell show that once a massive burst of carbon dioxide heats the planet, life in the oceans can overreact, stripping CO₂ from the air so aggressively that the world ends up far colder than it started. Their simulations help explain past “Snowball Earth” episodes, when ice reached almost from pole to pole. The same feedbacks could still exist today, but a more oxygen-rich atmosphere makes an extreme ice age less likely. Crucially, this is no escape hatch from today’s crisis: the cooling would take hundreds of thousands of years, while dangerous heat, rising seas and collapsing ecosystems hit within decades.
Brazil is preparing to host the COP30 climate summit in the Amazon city of Belém while its own climate credentials are under intense scrutiny. Just weeks before delegates arrive, the government approved a controversial Petrobras exploration license in the Foz do Amazonas basin, opening the door to new offshore oil near the mouth of the rainforest’s river system. The decision comes despite sharp drops in Amazon deforestation and mounting evidence that fires and drought are already pushing the region closer to a dangerous tipping point. Scientists and campaigners warn that expanding oil in one of the world’s most critical carbon sinks undermines global efforts to phase out fossil fuels and leaves Brazil’s claims to climate leadership hanging by a thread.
A new assessment from the UN Environment Programme’s Emissions Gap Report 2025: Off Target shows that a decade of climate policy under the Paris Agreement has shaved projected warming this century from roughly 3–5°C down to about 2.3–2.5°C, if all national climate pledges are fully carried out. That is progress, but the report and a companion UNEP press release warn that the window to keep 1.5°C alive is now measured in just a few years, and a temporary overshoot of that limit is described as “inevitable”. The gap between today’s policies and what science demands remains enormous: current measures still point towards about 2.8°C of warming. Meanwhile, climate impacts and the economic damage they cause are already accelerating, with weather and climate extremes costing the EU nearly €45 billion per year in the early 2020s, according to the European Environment Agency. With COP30 approaching, the UN is blunt: only unprecedented, immediate cuts in fossil fuel use can prevent this trajectory from hardening into full-blown climate breakdown.
For decades, the US Environmental Protection Agency allowed heavy industrial polluters to estimate their own emissions of cancer-causing chemicals instead of measuring what actually drifts into nearby neighborhoods. A new ProPublica investigation based on fence-line air monitoring around 20 large facilities finds that real-world pollution was almost always higher – and sometimes tens to more than a thousand times higher – than what companies reported, meaning millions of people may face far greater cancer risks than regulators assumed. The Biden administration responded in 2024 with rules requiring steel, coke and chemical plants to install permanent monitors, but President Trump’s EPA has now moved to delay and weaken those protections while granting dozens of plants temporary exemptions. Residents in industrial towns from western Pennsylvania to Louisiana’s “Cancer Alley” say the stakes are life-or-death, and public health experts warn that every year of inaction locks in avoidable disease and early deaths.
The latest United Nations “Emissions Gap” analysis shows that even after a new round of climate pledges, the world is still heading for around 2.3–2.5°C of warming this century if governments actually deliver on their promises – and as much as 2.8°C if they merely continue with today’s policies. The apparent improvement since last year’s report is tiny, and part of it is wiped out by the planned withdrawal of the United States from the Paris Agreement and sweeping rollbacks of US climate rules. At the same time, 2024 was the hottest year ever recorded, with global temperatures hovering around 1.5°C above pre-industrial levels. Scientists now say that crossing the Paris 1.5°C limit on a long-term basis is “very likely” within the next decade unless emissions fall sharply, locking in deadlier heat, rising seas and irreversible damage.
