Climate challenge: A decade after the Paris Agreement

Ten years after the Paris Agreement took effect, newly released climate datasets show the world warming at an accelerating pace, with 2025 ranking among the three hottest years ever recorded, and ocean heat and sea levels crossing new thresholds.

U.S. President Donald Trump, a climate-change sceptic, has rolled back a series of environmental policies over the past year and has described climate change as a hoax - a stance which has helped lead to the environmental agenda being challenged across the globe.

Although countries agreed a deal to pledge more funding for poorer countries to adapt to extreme weather at the annual United Nations meeting in Brazil last year, they failed to agree on more explicit plans to phase out fossil fuels and strengthen emissions-cutting plans.

Data from some of the world's leading scientific agencies shows global warming has sped up markedly since the mid‑2010s.

EMISSIONS: A WIDENING GAP

The World Meteorological Organization's Global Atmosphere Watch network shows concentrations of carbon dioxide, methane and nitrous oxide climbing to record highs, driving the temperature spike observed from 2023 to 2025, scientists say.

Global fossil fuel carbon dioxide emissions were projected to climb to a record 38.1 billion tonnes in 2025, driven by rising coal, oil and gas use despite rapid growth in renewable energy, according to the latest Global Carbon Budget report.

The report - produced by an international team of more than 130 scientists - estimated global fossil fuel CO₂ emissions would rise 1.1% in 2025, pushing atmospheric CO₂ concentrations to roughly 52% above pre‑industrial levels.

Researchers warn there is only room for about 170 billion more tonnes of CO₂ - equivalent to roughly four years of emissions at current rates - if the world wants to cap global warming at 1.5° Celsius above the pre-industrial average.

Emissions were projected to increase in 2025 in China, India, the United States and the European Union, while falling in Japan, although China has made significant investments in renewable energy.

TEMPERATURES: A DECADE OF ACCELERATION

NASA's Goddard Institute for Space Studies said the Earth's surface in 2025 was 1.19°C above the 1951–1980 average, effectively tying with 2023 as one of the warmest years ever measured.

The WMO's consolidated dataset places 2025 at 1.44°C above pre‑industrial levels, ranking it among the top-three warmest years over the 176 years of recorded temperatures. [nasa.gov] [wmo.int] [berkeleyearth.org]

ARCTIC: RAPID COLLAPSE OF SEA ICE

The U.S. National Oceanic and Atmospheric Administration’s 2025 Arctic Report Card confirmed that October 2024–September 2025 was the warmest period since 1900, and the region continues to warm more than twice as fast as the global average.

Sea‑ice extent reached the lowest winter maximum ever recorded in March 2025, at about 14.47 million square kilometers, according to the U.S. National Ice Center.

OCEANS: HEAT AND RISING SEAS

The oceans absorbed record amounts of heat in 2025, setting a new global high for upper‑ocean heat content, according to NOAA and Berkeley Earth.

Sea levels, measured by tide gauges and satellites, continue to rise. The Intergovernmental Panel on Climate Change projects a 0.20–0.29 meter rise by 2050 relative to 1995–2014.

Countries' territorial and consumption-based CO₂ emissions in 2024 https://reut.rs/4rZoUQV

Global anomalies in surface air temperature in 2025 https://reut.rs/46UWCyC

Arctic ice shrunk in ten years since Paris agreement https://reut.rs/40dmrGk

Global coastal cities at risk from sea level rise https://reut.rs/4kAzATu

-Reporting by Canan Sevgili, Vera Dvorakova, Lucie Barbier and Alessandro Parodi; Editing by Simon Jessop and David Holmes/Reuters