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Despite working on polar science for the British Antarctic Survey for 20 years, Louise Sime finds the magnitude of potential sea-level rise hard to comprehend

In a rapidly changing climate, evidence-based decision-making benefits from up-to-date and timely information. Here we compile monitoring datasets (published at https://doi.org/10.5281/zenodo.15639576; Smith et al., 2025a) to produce updated estimates for key indicators of the state of the climate system: net emissions of greenhouse gases and short-lived climate forcers, greenhouse gas concentrations, radiative forcing, the Earth's energy imbalance, surface temperature changes, warming attributed to human activities, the remaining carbon budget, and estimates of global temperature extremes. This year, we additionally include indicators for sea-level rise and land precipitation change. We follow methods as closely as possible to those used in the IPCC Sixth Assessment Report (AR6) Working Group One report.

Ocean acidification has already crossed a crucial threshold for planetary health, scientists say in unexpected finding

For around 2,000 years, global sea levels varied little. That changed in the 20th century. They started rising and have not stopped since — and the pace is accelerating. Scientists are scrambling to understand what this means for the future just as President Trump strips back agencies tasked with monitoring the oceans.

Have you ever thought about what would happen if all life in the ocean disappeared? A recent study explores this extreme scenario to understand how ocean biology shapes the past, present, and future climate. The ocean plays a critical role in regulating Earth's climate. It is a massive carbon store that absorbs about 25% of human-caused emissions and thus helps maintain a relatively low CO2 level in the atmosphere. But what would happen if all marine life—from the tiniest plankton to the largest whales—disappeared? A recent study delves into this extreme scenario to uncover the crucial role that ocean biology plays in mitigating climate change.

We investigate the probabilities of triggering climate tipping points under five Shared Socioeconomic Pathways (SSPs) and how they are altered by including the additional carbon emissions that could arise from tipping points within the Earth's carbon cycle. The crossing of a climate tipping point at a threshold level of global mean surface temperature (threshold temperature) would commit the affected subsystem of the Earth to abrupt and largely irreversible changes with negative impacts on human well-being. However, it remains unclear which tipping points would be triggered under the different SSPs due to uncertainties in the climate sensitivity to anthropogenic greenhouse gas emissions, the threshold temperatures and timescales of climate tipping points, and the response of tipping points within the Earth's carbon cycle to global warming. We include those uncertainties in our analysis to derive probabilities of triggering for 16 previously identified climate tipping points within the Earth system.

Global temperature for 2025 should decline little, if at all, from the record 2024 level. Absence of a large temperature decline after the huge El Nino-spurred temperature increase in 2023-24 will provide further confirmation that IPCC’s best estimates for climate sensitivity and aerosol climate forcing were both underestimates. Specifically, 2025 global temperature should remain near or above +1.5C relative to 1880-1920, and, if the tropics remain ENSO-neutral, there is good chance that 2025 may even exceed the 2024 record high global temperature.

Global sea level rose faster than expected in 2024, mostly because of ocean water expanding as it warms, or thermal expansion. According to a NASA-led analysis, last year’s rate of rise was 0.23 inches (0.59 centimeters) per year, compared to the expected rate of 0.17 inches (0.43 centimeters) per year.

... An “acid” test of our interpretation will be provided by the 2025 global temperature: unlike the 1997-98 and 2015-16 El Ninos, which were followed by global cooling of more than 0.3°C and 0.2°C, respectively, we expect global temperature in 2025 to remain near or above the 1.5°C level. Indeed, the 2025 might even set a new record despite the present weak La Nina. There are two independent reasons. First, the “new” climate forcing due to reduction of sulfate aerosols over the ocean remains in place, and, second, high climate sensitivity (~4.5°C for doubled CO2) implies that the warming from recently added forcings is still growing significantly.

The exponential rise in microplastic pollution over the past 50 years may be reflected in increasing contamination in human brains, according to a new study. It found a rising trend in micro- and nanoplastics in brain tissue from dozens of postmortems carried out between 1997 and 2024. The researchers also found the tiny particles in liver and kidney samples.

Human-caused climate change increased the likelihood and intensity of the hot, dry and windy conditions that fanned the flames of the recent devastating Southern California wildfires, a scientific study found. But the myriad of causes that go into the still smoldering fires are complex, so the level of global warming's fingerprints on weeks of burning appears relatively small compared to previous studies of killer heat waves, floods and droughts by the international team at World Weather Attribution. Tuesday's report, too rapid for peer-review yet, found global warming boosted the likelihood of high fire weather conditions in this month's fires by 35% and its intensity by 6%.

Wildfires that blazed around the world in 2024 helped to drive a record annual leap in carbon dioxide levels in the atmosphere, surprising scientists. The data shows humanity is moving yet deeper into a dangerous world of supercharged extreme weather.

Thirteen of the ports with the highest supertanker traffic will be seriously damaged by just 1 metre of sea level rise, the analysis found. The researchers said two low-lying ports in Saudi Arabia – Ras Tanura and Yanbu – were particularly vulnerable. Both are operated by Aramco, the Saudi state oil firm, and 98% of the country’s oil exports leave via these ports.

Visualize and download global and local sea level projections from the Intergovernmental Panel on Climate Change Sixth Assessment Report.

NASA satellites discovered that Earth's surface has lost enough water to empty Lake Erie two and a half times since 2015. And the problem could be here to stay.

High-level policy discussions have built momentum for “food system transformation” that would help farmers address the climate crisis.

Small increase in temperature of intruding water could lead to very big increase in loss of ice, scientists say

A long-term sea level dataset shows ocean surface heights continuing to rise at faster and faster rates over decades of observations. Global average sea level rose by about 0.3 inches (0.76 centimeters) from 2022 to 2023, a relatively large jump due mostly to a warming climate and the development of a strong El Niño. The total rise is equivalent to draining a quarter of Lake Superior into the ocean over the course of a year.

A chemical that takes thousands of years to break down is found in England's freshwater fish at 1,000 times above safe levels – and could end up on our dinner tables

In March and April 2023, some Earth scientists began to point out that average sea surface temperatures had surpassed the highest levels seen in a key data record maintained by NOAA. Months later, they remain at record levels, with global sea surface temperatures 0.99°C (1.78°F) above average in July. That was the fourth consecutive month they were at record levels.

Waves of severe thunderstorms in the U.S. during the first half of this year led to $34 billion in insured losses, an unprecedented level of financial damage in such a short time as climate change contributes to the frequency and severity of violent meteorological events. The reinsurer Swiss Re Group said Wednesday that damages from convective storms in the U.S., which can come with hail, lightning, heavy rain and high winds, accounted for nearly 70% of the $50 billion in global catastrophic damages so far this year. The storms in the U.S. were so severe, there were 10 that resulted in damages of $1 billion or more, almost double the average over the last decade.

Global coal consumption climbed to a new all-time high in 2022 and will stay near that record level this year as strong growth in Asia for both power generation and industrial applications outpaces declines in the United States and Europe, according to the IEA’s latest market update.

With the continent holding enough ice to raise sea levels by many metres if it was to melt, polar scientists are scrambling for answers

Major mapping project reveals PFAS have been found at high levels at thousands of sites across Europe. EURACTIV's media partner, The Guardian, reports. Pollutants known as “forever chemicals”, which don’t break down in the environment, build up in the body and may be toxic, have been found at high levels at thousands of sites across the UK and Europe, a major mapping project has revealed.

An increase in the pace at which sea levels are rising threatens “a mass exodus of entire populations on a biblical scale”, the UN secretary general has warned. The climate crisis is causing sea levels to rise faster than for 3,000 years, bringing a “torrent of trouble” to almost a billion people, from London to Los Angeles and Bangkok to Buenos Aires, António Guterres said on Tuesday. Some nations could cease to exist, drowned under the waves, he said.

A community of Indigenous peoples worried that mercury used by gold miners was contaminating the fish they eat. So they created a DIY team to find out more.

Scientists warn world ‘is heading in wrong direction’ amid rise in nitrous oxide, carbon dioxide and methane.Atmospheric levels of all three greenhouse gases have reached record highs, according to a study by the World Meteorological Organization, which scientists say means the world is “heading in the wrong direction”.

WMO records biggest increase in methane concentrations since start of measurements

Germany’s Rhine, one of Europe’s key waterways, is just days away from being closed to commercial traffic because of very low levels caused by drought, authorities and industry have warned. Crucially, the impending crisis could lead energy companies to cut their output, one of the country’s biggest gas companies has said.

Methane has a mixture of both natural and anthropogenic sources. Around 40% of methane emissions comes from natural sources, while 60% comes from anthropogenic sources such as agriculture, fossil fuel exploitation and landfills.In situ methane measurements from 2020 showed the largest annual increase of methane concentrations since the 1980s, with this record surpassed in 2021. The year of 2020 was unique owing to the global pandemic, yet methane concentrations continued to rise despite a reduction in economic activity.

Climate tipping points in the Antarctica, the Arctic and the Amazon are at risk of being reached before or at the current level of global warming of 1.2 degrees Celsius, requiring a “major rethink” of global climate goals and the action necessary to achieve them, according to a recent report.

The focus of the opening day of the 17th session of the United Nations Forum on Forests (UNFF17) was a High-Level Roundtable on the UNFF response to, role in, and expectations from forest-related multilateral developments. Members of the Forum also started providing updates on their actions in support of the three UNFF thematic priorities for 2021-2022; these will continue on Tuesday.

Scientists at Scripps Institution of Oceanography at UC San Diego used an unprecedented technique to detect that levels of helium are rising in the atmosphere, resolving an issue that has lingered among atmospheric chemists for decades.

There is a 50:50 chance of the annual average global temperature temporarily reaching 1.5 °C above the pre-industrial level for at least one of the next five years – and the likelihood is increasing with time, according to a new climate update issued by the World Meteorological Organization (WMO).

Against the backdrop of the water crisis in the Colorado River Basin, where the country's largest reservoirs are plunging at an alarming rate, California's two largest reservoirs — Shasta Lake and Lake Oroville — are facing a similar struggle.

Following record-level declines in 2020, near-real-time data indicate that global CO2 emissions rebounded by 4.8% in 2021, reaching 34.9 GtCO2. These 2021 emissions consumed 8.7% of the remaining carbon budget for limiting anthropogenic warming to 1.5 °C, which if current trajectories continue, might be used up in 9.5 years at 67% likelihood.

Momentum to phase out unabated coal use is growing globally. This transition is critical to meeting the Paris climate goals but can potentially lead to large amounts of stranded assets, especially in regions with newer and growing coal fleets. Here we combine plant-level data with a global integrated assessment model to quantify changes in global stranded asset risks from coal-fired power plants across regions and over time. With new plant proposals, cancellations, and retirements over the past five years, global net committed emissions in 2030 from existing and planned coal plants declined by 3.3 GtCO2 (25%). While these emissions are now roughly in line with initial Nationally Determined Contributions (NDCs) to the Paris Agreement, they remain far off track from longer-term climate goals. Progress made in 2021 towards no new coal can potentially avoid a 24% (503 GW) increase in capacity and a 55% ($520 billion) increase in stranded assets under 1.5 °C. Stranded asset risks fall disproportionately on emergin

Rapidly rising levels of atmospheric methane are "very bad news for humanity and the planet," warned one observer.

Emerging ice-sheet modeling suggests once initiated, retreat of the Antarctic Ice Sheet (AIS) can continue for centuries. Unfortunately, the short observational record cannot resolve the tipping points, rate of change, and timescale of responses. Iceberg-rafted debris data from Iceberg Alley identify eight retreat phases after the Last Glacial Maximum that each destabilized the AIS within a decade, contributing to global sea-level rise for centuries to a millennium, which subsequently re-stabilized equally rapidly.

Exclusive: Greta Thunberg among young people filing legal suit for climate crisis to be declared a global level 3 emergency

In the Paris Agreement, over 200 countries decided upon limiting global warming to below 2 degrees Celsius. Belgium, The Netherlands and Luxembourg ratified the agreement and consecutively, in November 2018, they signed the Benelux Talanoa Declaration, emphasizing their common pathway in achieving these goals. In addition, the Benelux Talanoa Declaration calls upon the creation of a platform to enhance further dialogue between the Benelux countries, as well as with stakeholders committed and working towards to the climate objectives on a policy, technical, scientific, practical or more conceptual level.

Picture a plastic bowl. Put a large piece of ice in it—one tall enough that it rises high above the bowl’s rim. Now melt the ice. The bowl will catch most of the water, but not all of it. Since the ice is tall, the bowl will reach full capacity before the block melts completely. With no place else to go, the extra water will spill over the lip and onto the counter.

For the first time on record, precipitation on Saturday at the summit of Greenland — roughly two miles above sea level — fell as rain and not snow.

Global heating above 1.5C will be “catastrophic” for Pacific island nations and could lead to the loss of entire countries due to sea level rise within the century, experts have warned.

Lake Oroville’s water level has fallen so low that on Thursday, for the first time since the dam was built in 1967, its power plant was shut down because there is no longer enough water to spin the turbines and generate electricity.Last Friday, hoping to avert any more power shutdowns, Gov. Gavin Newsom issued an emergency order that temporarily waives some air pollution rules to allow natural gas power plants to generate more electricity and pays industries $2 a kilowatt-hour to reduce their electricity use during heat waves.

Abrupt disruptions to Earth's climate thousands of years ago that caused extreme sea-level rise and mass ice cap melting can serve as an early warning system for today's planetary tipping points, according to new research.

Officials prepare to elevate streets despite financial shortfalls, amid recognition that not every home can be save. Long famed for its spectacular fishing, sprawling coral reefs and literary residents such as Ernest Hemingway, the Florida Keys is now acknowledging a previously unthinkable reality: it faces being overwhelmed by the rising seas and not every home can be saved.

Emissions rose to 419 parts per million in May, the highest such measurement in the 63 years that the data has been recorded

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