- Greenhouse gases climb: Major greenhouse gas concentrations, including carbon dioxide, methane, and nitrous oxide, continued to rise during 2012. Following a slight decline in manmade emissions associated with the global economic downturn, global CO2 emissions from fossil fuel combustion and cement production reached a record high in 2011 of 9.5 ± 0.5 petagrams (1,000,000,000,000,000 grams) of carbon , and a new record of 9.7 ± 0.5 petagrams of carbon is estimated for 2012. Atmospheric CO2 concentrations increased by 2.1 ppm in 2012, reaching a global average of 392.6 ppm for the year. In spring 2012, for the first time, the atmospheric CO2 concentration exceeded 400 ppm at several Arctic observational sites.
- Cool temperature trends continue in Earth’s lower stratosphere: The average lower stratospheric temperature, about six to ten miles above the Earth’s surface, for 2012 was record to near-record cold, depending on the dataset. Increasing greenhouse gases and decline of stratospheric ozone tend to cool the stratosphere while warming the planet near-surface layers.
The 2012 State of the Climate report is peer-reviewed and published annually as a special supplement to the Bulletin of the American Meteorological Society. This year marks the 23rd edition of the report, which is part of the suite of climate services NOAA provides to government, the business sector, academia, and the public to support informed decision-making.
Check the following link to read/download the Full Report:
http://www.ncdc.noaa.gov/bams-state-of-the-climate/2012.php
Source: NOAA.