The latest statistics are in from 2013 and both NASA’s and NOAA’s measurements of global temperatures show Earth continued to experience temperatures warmer than those measured several decades ago.
NASA scientists say 2013 tied with 2009 and 2006 for the seventh warmest year since 1880, continuing a long-term trend of rising global temperatures, while NOAA – which uses a different method of analyzing temperature data – said that 2013 tied with 2003 as 4th-warmest year globally since 1880.
“The long-term trends are very clear, and they’re not going to disappear,” said climatologist Gavin Schmidt from NASA’s Goddard Institute for Space Studies (GISS). “It isn’t an error in our calculations.”
NASA data shows that since 1950, average temperatures have increased 1.1°F to an average of 58.3° in 2013.
NOAA data shows the average temperature across global land and ocean surfaces was 1.12 degrees above the 20th-century average. This is the 37th consecutive year that the annual temperature was above the long-term average.
Both NASA and NOAA scientists say the increase in greenhouse gas levels continue to drive the temperature increase.
Additionally, with the exception of 1998, the 10 warmest years in the 134-year record all have occurred since 2000, with 2010 and 2005 ranking as the warmest years on record.
NASA says the average temperature in 2013 was 58.3 degrees Fahrenheit (14.6 Celsius), which is 1.1 F (0.6 C) warmer than the mid-20th century baseline. The average global temperature has risen about 1.4 degrees F (0.8 C) since 1880, according to the new analysis. Exact rankings for individual years are sensitive to data inputs and analysis methods.
“Long-term trends in surface temperatures are unusual and 2013 adds to the evidence for ongoing climate change,” GISS climatologist Gavin Schmidt said. “While one year or one season can be affected by random weather events, this analysis shows the necessity for continued, long-term monitoring.”
Scientists emphasize that weather patterns always will cause fluctuations in average temperatures from year to year, but the continued increases in greenhouse gas levels in Earth’s atmosphere are driving a long-term rise in global temperatures. Each successive year will not necessarily be warmer than the year before, but with the current level of greenhouse gas emissions, scientists expect each successive decade to be warmer than the previous.
More from NASA:
Carbon dioxide is a greenhouse gas that traps heat and plays a major role in controlling changes to Earth’s climate. It occurs naturally and also is emitted by the burning of fossil fuels for energy. Driven by increasing man-made emissions, the level of carbon dioxide in Earth’s atmosphere presently is higher than at any time in the last 800,000 years.
The carbon dioxide level in the atmosphere was about 285 parts per million in 1880, the first year in the GISS temperature record. By 1960, the atmospheric carbon dioxide concentration, measured at the National Oceanic and Atmospheric Administration’s (NOAA) Mauna Loa Observatory in Hawaii, was about 315 parts per million. This measurement peaked last year at more than 400 parts per million.
While the world experienced relatively warm temperatures in 2013, the continental United States experienced the 42nd warmest year on record, according to GISS analysis. For some other countries, such as Australia, 2013 was the hottest year on record.
The temperature analysis produced at GISS is compiled from weather data from more than 1,000 meteorological stations around the world, satellite observations of sea-surface temperature, and Antarctic research station measurements, taking into account station history and urban heat island effects. Software is used to calculate the difference between surface temperature in a given month and the average temperature for the same place from 1951 to 1980. This three-decade period functions as a baseline for the analysis. It has been 38 years since the recording of a year of cooler than average temperatures.
The GISS temperature record is one of several global temperature analyses, along with those produced by the Met Office Hadley Centre in the United Kingdom and NOAA’s National Climatic Data Center in Asheville, N.C. These three primary records use slightly different methods, but overall, their trends show close agreement.
Editor’s note: First quote from Gavin Schmidt is from Jacob Ward on Twitter.