The amount of greenhouse gases in the atmosphere has reached a new high in 2013, driven by a flow in levels of carbon dioxide, according to the World Meteorological Organization’s annual Greenhouse Gas Bulletin.
The report draws immediate attention into the need for concerted international action against potentially devastating climate change.
In 2013, concentration of carbon in the atmosphere was 142 percent of the pre-industrial era, and of methane and nitrous oxide 253 percent and 121 percent respectively.
Carbon dioxide accounted for 80 percent of the 34 percent increase in radiative forcing by long-lived greenhouse gases from 1990 to 2013, according to the U.S. National Oceanic and Atmospheric Administration (NOAA) Annual Greenhouse Gas Index.
The opinions from WMO’s Global Atmosphere Watch (GAW) showed that carbon levels increased much 2012 and 2013 than during any other year since 1984, possibly due to reduced carbon acceptance by the earth as well as increasing carbon rate.
On the global scale, the amount of CO2 in the atmosphere reached 396.0 per million in 2013. The atmospheric increase of CO2 from 2012 to 2013 was 2.9 parts per million. Concentrations of CO2 vary with seasonal and regional fluctuations.
At the current rate, the global annual average CO2 concentration will cross 400 parts per million thresholds in 2015 or 2016. Last year the concentration of carbon dioxide in the atmosphere increased at the fastest rate for nearly 30 years.
Methane, the second important long-lived greenhouse gas is emitted by natural sources as well as from human activities. Atmospheric methane reached a new high of about 1824 parts per billion in 2013. Since 2007, atmospheric methane has been increasing again after a temporary period of leveling-off.
Nitrous oxide is emitted into the atmosphere from both natural and anthropogenic sources. Its atmospheric concentration in 2013 was about 325.9 parts per billion, with an impact on climate, over a 100-year period 298 times greater than carbon dioxide. It also plays an important role in the destruction of the ozone layer.
The climate is changing and weather is becoming more extreme due to human activities such as the burning of fossil fuels, said, Michel Jarraud, secretary general, WMO.
This trend has to be reversed by cutting emissions of CO2 and other greenhouse gases across the board as we are running out of time, said, Jarraud.
Carbon dioxide remains in the atmosphere for many hundreds of years and in the ocean for even longer. Past, present and future CO2 emissions will have a cumulative impact on both global warming and ocean acidification, he continued.
The Bulletin provides a scientific base for decision-making. The temperature should increase only within 2°C to give the planet a chance and children and grandchildren a future, said, Jarraud.
The section on ocean acidification was prepared in collaboration with the International Ocean Carbon Coordination Project (IOCCP) of the Intergovernmental Oceanographic Commission of UNESCO (IOC-UNESCO), the Scientific Committee on Oceanic Research (SCOR), and the Ocean Acidification International Coordination Centre (OA-ICC) of the International Atomic Energy Agency (IAEA).
The ocean absorbs one-fourth of anthropogenic CO2 emissions, reducing the increase in atmospheric CO2. Enhanced ocean CO2 uptake alters the marine carbonate system and lead to increasing acidity. The ocean’s acidity increase is already measurable as oceans take up about 4 kilograms of CO2 per day per person.
The inclusion of ocean acidification in this Bulletin is appropriate. It is high time that the ocean, primarily responsible for the climate change, becomes an important part of these discussions, said, Wendy Watson-Wright, executive secretary, Intergovernmental Oceanographic Commission of UNESCO.
If global warming is not a strong reason to cut CO2 emissions, ocean acidification should be, since its effects are being felt and will increase in future, she said.
The current rate of ocean acidification appears unprecedented at least over the last 300 million years, based on proxy-data from paleo archives.
In the future, acidification will continue to accelerate at least until mid-century, based on projections from Earth system models.