Dec 9, 2015
The planet reached two important climate milestones this year. The globally averaged concentration of CO2 reached 400 parts per million, and the global average temperature climbed to more than 1°C (1.8°F) above pre-industrial levels.
Within each year, there is a small saw-tooth pattern to the atmospheric CO2 concentration. As vegetation blossoms in the Northern Hemisphere each spring, CO2 is taken in, but returned to the atmosphere during the fall. As a result, there was a brief drop below 400 ppm this past summer. However, with winter settling in, that level will be reached again soon. Additionally, the current strong El Niño likely means more drought in tropical regions, leading to an increase in forest fires and more CO2 in the atmosphere, further suggesting the concentration is unlikely go below 400 ppm for the foreseeable future.
NOAA uses a slightly different baseline when reporting the global average temperature change. Through the first 10 months of this year, the temperature of combined land and ocean surfaces is 0.86°C (1.55°F) above the 20th century average. And just like the U.K. Met Office, the NOAA data indicate that the warming shows no sign of changing direction.
Jun 26, 2016
Analysis of ancient air bubbles recovered from deep within Antarctic ice indicates that current level of atmospheric carbon dioxide is the highest in at least 800,000 years.
Apr 20, 2016
Coming off of the hottest year on record globally, international leaders are meeting this week in New York to sign the historic Paris Climate Agreement.
Nov 3, 2017
The U.S. Global Change Research Program released the Climate Science Special Report.