This article documents events, research findings, scientific and technological advances, and human actions to measure, predict, mitigate, and adapt to the effects of global warming and climate change—during the year 2020.
Summaries
The December 2020 Lancet Countdown review concluded that trends in 2020 showed "a concerning paucity of progress" in numerous sectors, including "a continued failure to reduce the carbon intensity of the global energy system, an increase in the use of coal-fired power, and a rise in agricultural emissions and premature deaths from excess red meat consumption. These issues (were) in part counteracted by the growth of renewable energy and improvements in low-carbon transport." Despite increasing climate suitability for infectious disease transmission and falling crop yield potential, "the global response has remained muted" but "2020 will probably be an inflection point for several of the indicators (to be) presented during the coming decade". The survey further noted that "the nature and extent of the economic impact and response to the COVID-19 pandemic will have a defining role in determining whether the world meets the commitments of the Paris Agreement".
Measurements and statistics
NASA GISS reported 2020's globally averaged temperature was 1.84 °F (1.02 °C) warmer than the baseline 1951-1980 mean, slightly greater than 2016 but within the margin of error of the analysis, making 2020 effectively tie 2016 as the warmest year on record despite La Niña's cooling effect. Independently, Copernicus (EU) concurred with NASA's conclusion, while NOAA and the U.K. Met Office concluded 2020 was the second warmest. High northern latitudes: Siberia recorded its second warmest January–June temperatures on record—more than 5°C (9°F) above average—including up to 10°C (18°F) above average in June. Verkhoyansk, located north of the arctic circle, recorded a temperature of 38°C (100°F) on 20 June. An analysis showed that, without human-induced climate change, these January–June temperatures would happen less than once in every 80,000 years. The fire season in Sakha (Siberia) was unprecedented in the 20-year MODIS record in terms of an earlier start and northern extent, with some fires burning only about 11 km from the Chukchi Sea. From March through June, the burned area was greater than 2.9 times the 20-year mean. End-of-winter Arctic sea ice extent was the 11th lowest, and the end-of-summer extent the second-lowest, in the 1979-2020 satellite record. April 2020 Northern Hemisphere sea ice volume was approximately 1,000 km3 below the 2010-2019 average, and October 2020 sea ice volume showed the lowest value in the preceding 10 years because of a second largest summer loss of 15.215 km3.