Albedo Weekly

The climate research weekly

Albedo Weekly: the warming world, measured and explained

Every figure on global warming from the agencies that measure it, the projects that answer it, and a weekly digest of what changed. Our feature this season: the Earthshot Prize Awards Night in Mumbai.

Scientists sample melt ponds on Arctic sea ice
Fig. 1 · Scientists sample melt ponds on Arctic sea ice. Bright ice reflects sunlight; dark water absorbs it. That reflectivity is called albedo. Photo: Kathryn Hansen, Public domain, via Wikimedia Commons
1880: -0.17 °C1881: -0.09 °C1882: -0.11 °C1883: -0.18 °C1884: -0.28 °C1885: -0.33 °C1886: -0.31 °C1887: -0.36 °C1888: -0.18 °C1889: -0.11 °C1890: -0.36 °C1891: -0.22 °C1892: -0.27 °C1893: -0.31 °C1894: -0.30 °C1895: -0.23 °C1896: -0.11 °C1897: -0.11 °C1898: -0.28 °C1899: -0.18 °C1900: -0.08 °C1901: -0.16 °C1902: -0.28 °C1903: -0.37 °C1904: -0.47 °C1905: -0.26 °C1906: -0.22 °C1907: -0.38 °C1908: -0.42 °C1909: -0.48 °C1910: -0.44 °C1911: -0.44 °C1912: -0.37 °C1913: -0.34 °C1914: -0.15 °C1915: -0.14 °C1916: -0.36 °C1917: -0.46 °C1918: -0.30 °C1919: -0.27 °C1920: -0.27 °C1921: -0.18 °C1922: -0.28 °C1923: -0.26 °C1924: -0.27 °C1925: -0.22 °C1926: -0.11 °C1927: -0.22 °C1928: -0.20 °C1929: -0.36 °C1930: -0.15 °C1931: -0.09 °C1932: -0.16 °C1933: -0.28 °C1934: -0.13 °C1935: -0.20 °C1936: -0.15 °C1937: -0.03 °C1938: +0.00 °C1939: -0.02 °C1940: +0.12 °C1941: +0.18 °C1942: +0.06 °C1943: +0.09 °C1944: +0.20 °C1945: +0.09 °C1946: -0.07 °C1947: -0.03 °C1948: -0.11 °C1949: -0.11 °C1950: -0.17 °C1951: -0.07 °C1952: +0.01 °C1953: +0.08 °C1954: -0.13 °C1955: -0.14 °C1956: -0.19 °C1957: +0.05 °C1958: +0.06 °C1959: +0.03 °C1960: -0.02 °C1961: +0.06 °C1962: +0.03 °C1963: +0.05 °C1964: -0.20 °C1965: -0.11 °C1966: -0.06 °C1967: -0.02 °C1968: -0.08 °C1969: +0.05 °C1970: +0.03 °C1971: -0.08 °C1972: +0.01 °C1973: +0.16 °C1974: -0.07 °C1975: -0.01 °C1976: -0.10 °C1977: +0.18 °C1978: +0.07 °C1979: +0.16 °C1980: +0.26 °C1981: +0.32 °C1982: +0.14 °C1983: +0.31 °C1984: +0.16 °C1985: +0.12 °C1986: +0.18 °C1987: +0.32 °C1988: +0.39 °C1989: +0.27 °C1990: +0.45 °C1991: +0.41 °C1992: +0.22 °C1993: +0.23 °C1994: +0.31 °C1995: +0.45 °C1996: +0.33 °C1997: +0.47 °C1998: +0.61 °C1999: +0.38 °C2000: +0.39 °C2001: +0.53 °C2002: +0.63 °C2003: +0.62 °C2004: +0.53 °C2005: +0.68 °C2006: +0.64 °C2007: +0.66 °C2008: +0.54 °C2009: +0.66 °C2010: +0.72 °C2011: +0.61 °C2012: +0.65 °C2013: +0.67 °C2014: +0.75 °C2015: +0.89 °C2016: +1.01 °C2017: +0.91 °C2018: +0.85 °C2019: +0.98 °C2020: +1.01 °C2021: +0.85 °C2022: +0.89 °C2023: +1.17 °C2024: +1.28 °C2025: +1.18 °C
1880–2025, one stripe per year. 2025 was +1.18 °C against the 1951–1980 average; 2026 so far +1.23 °C. Data: NASA GISS.

Supporter feature · 17 November 2026

Earthshot Prize 2026: Mumbai

Prince William's prize comes to India for the first time. Fifteen finalists, five winners, £1 million each to scale what already works.

Meet all 15 finalists

24days to go Awards Night · 17 November 2026 · Mumbai
  • Protect and Restore NatureIndigenous Desert Alliance Australia
  • Protect and Restore NatureBhutan Bhutan
  • Protect and Restore NatureYellowstone to Yukon Conservation Initiative Canada (with US)

The numbers right now

Full research library

Global mean temperature 2025 (consolidated, 8 datasets)

1.43 °C above baseline (±0.13)

2025 · 1850-1900

World Meteorological Organization · State of the Global Climate 2025

Human-induced warming 2025

1.37 °C above 1850-1900

2025 · 1850-1900

Forster et al. / IGCC · Indicators of Global Climate Change 2025

Arctic sea ice minimum 2026

4.6 million km²

2026-09-12

NASA / NSIDC · Arctic sea ice 2026 minimum

Reef area hit by bleaching-level heat stress (4th global event)

84 percent

2023-01 to 2025-06

NOAA NESDIS / Coral Reef Watch · World's fourth mass coral bleaching event likely ended

This week

Read 2026-W43

Research · Inside Climate News

Study Finds Mixed Pollution Trends in Northern China

New research reports that climate pollutant levels in the Beijing area have leveled off or started to decline, except for one greenhouse gas. It says a long effort to clean the city's air appears to be producing results.

Project · Mongabay

Work to revive Białowieża woodland linked to border concerns

A restoration effort is underway in Białowieża Forest, a primeval woodland shared by Poland and Belarus, as drainage, drought and fragmentation have left the ecosystem under pressure. The material also says the forest faces a new challenge from the threat from Russia.

Research · Inside Climate News

IUCN Study Projects Major Loss of Reef Function by 2075

A new IUCN assessment projects that by 2075 most shallow coral reefs could stop functioning as habitat and as a lifeline for hundreds of millions of people. This would affect both marine life and the many people who rely on reefs.