Earth's average surface temperature in 2022 tied with 2015 as the fifth warmest on record, according to an analysis by NASA.
Continuing the planet's long-term warming trend, global temperatures in 2022 were 1.6 degrees Fahrenheit, or 0.89 degrees Celsius, above the average for NASA's baseline period 1951-1980, scientists from NASA's Goddard Institute for Space Studies (GISS) in New York reported.
"This warming trend is alarming," said NASA Administrator Bill Nelson.
"Our warming climate is already making a mark: Forest fires are intensifying; hurricanes are getting stronger; droughts are wreaking havoc and sea levels are rising. NASA is deepening our commitment to do our part in addressing climate change," said Nelson.
The past nine years have been the warmest years since modern recordkeeping began in 1880. This meant Earth in 2022 was about 2 degrees Fahrenheit, or about 1.11 degrees Celsius, warmer than the late 19th century average, the study said.
"The reason for the warming trend is that human activities continue to pump enormous amounts of greenhouse gases into the atmosphere, and the long-term planetary impacts will also continue," said Gavin Schmidt, director of GISS.
Human-driven greenhouse gas emissions have rebounded following a short-lived dip in 2020 due to the COVID-19 pandemic, the study said.
Recently, NASA scientists, as well as international scientists, determined carbon dioxide emissions were the highest on record in 2022, the study said.
NASA also identified some super-emitters of methane - another powerful greenhouse gas - using the Earth Surface Mineral Dust Source Investigation instrument that launched to the International Space Station last year, the study said.
The Arctic region continues to experience the strongest warming trends - close to four times the global average - according to GISS research presented at the 2022 annual meeting of the American Geophysical Union, as well as a separate study.
Communities around the world are experiencing impacts scientists see as connected to the warming atmosphere and ocean. Climate change has intensified rainfall and tropical storms, deepened the severity of droughts, and increased the impact of storm surges.
Last year brought torrential monsoon rains that devastated Pakistan and a persistent megadrought in the U.S. Southwest. In September, Hurricane Ian became one of the strongest and costliest hurricanes to strike the continental U.S.
NASA's global temperature analysis was drawn from data collected by weather stations and Antarctic research stations, as well as instruments mounted on ships and ocean buoys. NASA scientists analyzed these measurements to account for uncertainties in the data and to maintain consistent methods for calculating global average surface temperature differences for every year, the study said.
These ground-based measurements of surface temperature were consistent with satellite data collected since 2002 by the Atmospheric Infrared Sounder on NASA's Aqua satellite and with other estimates, the study said.
NASA uses the period from 1951-1980 as a baseline to understand how global temperatures change over time. That baseline includes climate patterns such as La Nina and El Nino, as well as unusually hot or cold years due to other factors, ensuring it encompasses natural variations in Earth's temperature, the study said.
Many factors can affect the average temperature in any given year. For example, 2022 was one of the warmest on record despite a third consecutive year of La Nina conditions in the tropical Pacific Ocean, the study said.
NASA scientists estimate that La Nina's cooling influence may have lowered global temperatures slightly, about 0.11 degrees Fahrenheit or 0.06 degrees Celsius, from what the average would have been under more typical ocean conditions.
A separate, independent analysis by the National Oceanic and Atmospheric Administration (NOAA) concluded that the global surface temperature for 2022 was the sixth highest since 1880.
NOAA scientists used much of the same raw temperature data in their analysis, but had a different baseline period (1901-2000) and methodology. Although rankings for specific years did differ slightly between the records, they were in broad agreement and both reflected ongoing long-term warming, the study said.
NASA's full dataset of global surface temperatures through 2022, as well as full details with code of how NASA scientists conducted the analysis, are publicly available from GISS, the study said.