The United Nations weather agency, the World Meteorological Organization (WMO), has reported another record high in the levels of heat-trapping greenhouse gases in our atmosphere. The WMO releases an annual greenhouse gas bulletin, which has revealed that there is no sign of a reversal in the upward trend that is responsible for climate change, sea-level rise, ocean acidification, and extreme weather events. Interestingly, this report discusses concentrations rather than emissions. Concentrations differ from emissions as they represent what remains in the atmosphere after some gases are absorbed by seas, land, and trees. Since 1990, these long-lived gases have increased the climate’s warming impact by 41%.
Understanding Greenhouse Gases and Their Impact
In 2017, atmospheric CO2 reached 146% of the pre-industrial level. This is largely due to emissions from burning fossil fuels and cement production, deforestation and other changes in land-use. Other critical greenhouse gases, methane and nitrous oxide, also experienced rising levels in the atmosphere.
The rise in CO2 concentration from 2016 to 2017 was smaller than the jump between 2015 to 2016 due to El Niño’s impact, which peaked in 2015 and 2016. This climatic event triggered droughts in some parts of the world, decreasing the forests and vegetation’s capacity to absorb CO2, resulting in more remaining in the atmosphere.
The El Niño Effect
El Niño, translating to The Little Boy or Christ Child in Spanish, is a periodic climate occurrence characterized by warming waters in the east-central Pacific Ocean. This results in massive changes in wind directions, which can bring less rain to Southeast Asia and the Indian subcontinent while flooding other parts of the world with more rainfall.
The counterpart of El Niño is La Niña, meaning The Little Girl in Spanish. It represents times when the waters of the tropical eastern Pacific are colder than normal and trade winds blow more strongly than usual. Together, these two events form part of an ocean-atmosphere system oscillation known as the El Niño-Southern Oscillation, or ENSO cycle.
About World Meteorological Organization (WMO)
The WMO is a specialized United Nations agency dedicated to international cooperation and coordination regarding Earth’s atmosphere state and behavior, the atmosphere’s interaction with land and oceans, the produced weather and climate, and the distribution of water resources that result from it. The WMO originated from the International Meteorological Organization, which was founded in 1873 to facilitate weather information exchange across national borders. It became a specialized UN agency in 1951.
Greenhouse Gases Facts
| Gas | Percentage of Pre-industrial Level (2017) | Main Source |
|---|---|---|
| Atmospheric CO2 | 146% | Fossil fuel combustion, Cement production, Deforestation |
| Methane | 257% | Cattle farming, Rice cultivation, Fossil fuel extraction |
| Nitrous oxide | 122% | Fertilizer use and industry |
The Issue of Other Gases
Methane, the second most important greenhouse gas, makes up about 60% of the atmospheric volume due to human activities such as cattle farming, rice cultivation, and fossil fuel extraction. Nitrous Oxide, derived from both natural and human sources like fertilizer use and industry, is about 122% of pre-industrial levels.
Sulphur hexafluoride (SF6), a potent long-lived greenhouse gas, is produced by the chemical industry, primarily as an electrical insulator in power distribution equipment. Meanwhile, some hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), also potent greenhouse gases, are increasing at relatively fast rates, even though their abundance is still low.
Furthermore, the WMO discovered illicit production of CFC-11, a banned chemical that contributes to global warming and ozone destruction. At least some of this production appears to be occurring in China, contrary to the Montreal Protocol’s stipulation that CFC-11 is to be phased out of production.
The Montreal Protocol and Its Amendments
The Montreal Protocol, adopted on 16 September 1987, regulates nearly 100 man-made chemicals known as Ozone Depleting Substances (ODS). It provides for phasing out halogenated hydrocarbons like tetrachloride, CFCs used in aerosols, halons used in fire extinguishers, HydroChloroFluoroCarbons (HCFCs) used in refrigeration and foams, and methyl used in the agricultural fumigation activity.
Moreover, the Kigali amendment was incorporated into the protocol in 2016 to phase out HydroFluoroCarbon (HFC), a set of 19 gases extensively used in the air-conditioning and refrigeration industry. Although HFCs do not deplete the ozone layer, they are thousands of times more damaging to the environment than carbon dioxide in causing global warming.
The Implications of the WMO Report
This report by the WMO underlines the urgency highlighted in the recent Intergovernmental Panel on Climate Change (IPCC) 1.5C report. It warned that the world needs to reach carbon neutrality by 2050 to mitigate the worst impacts of climate change. This WMO bulletin precedes the Conference of Parties (COP24) meeting in Katowice, Poland, during which countries will discuss practical applications for the Paris climate agreement and ways to increase their ambitions to reduce warming gases.