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A new Global Methane Pledge announced at the United Nations Climate Change negotiations COP26 represents the first major international push to reduce emissions of a powerful but short-lived greenhouse gas.

The World Meteorological Organization welcomed the initiative. Bu it stressed that this must be accompanied by urgent action to reduce emissions of carbon dioxide, the main long-lived greenhouse gas.

« As Secretary-General of the United Nations, I have many battles, but the fight against the climate crisis is the most important battle of my life. It is a battle we can and must win. We cannot give up. I will not give up,” » tweeted UN Secretary-General António Guterres.

« The Climate Action struggle requires all hands on deck. It is everyone’s responsibility. Every country, every city, every company, every financial institution must radically, credibly & verifiably reduce their emissions & decarbonize their portfolios starting now, » tweeted Guterres, who returned to the negotiations to instill a sense of urgency.

The aim of the Global Methane Pledge, led by the United States of America and the European Union, is to reduce methane emissions by at least 30% by 2030. More than 100 countries, including major emitters, signed up to the pledge, which will support the Paris Agreement goal of limiting warming to well below 2 °C.

Methane is a powerful greenhouse gas which remains in the atmosphere for about a decade – a much shorter lifetime than carbon dioxide . Reducing atmospheric methane in the short term could support the achievement of the Paris Agreement and help in reaching many Sustainable Development Goals due to multiple co-benefits of methane mitigation.

Overwhelming support for the Methane Pledge was voiced at a 9 November  ministerial session of the Climate and Clean Air Coalition.

Ministers from 46 countries approved the Coalition’s 2030 Strategy, which will see scaled-up efforts to significantly reduce short-lived climate pollutants (SLCPs)—methane, hydrofluorocarbon (HFCs), black carbon, and tropospheric (ground level) ozone—by 2030.

The WMO has been a CCAC partner from 2014 and monitors globally the whole spectrum of the climate forcers from long-lived greenhouse gases to short-lived climate pollutants. Japan hosts the World Data Center for Greenhouse Gases where the data on major greenhouse gases (including methane) from WMO coordinated global observational network are freely available. Data on aerosol and tropospheric ozone are collected and disseminated by two other data centers supported by Norway.

At the ministerial event WMO Deputy Secretary-General Dr Elena Manaenkova committed WMO’s support to the new Global Methane Pledge.

“The WMO annually reports to UNFCCC COP on the atmospheric concentrations of the greenhouse gases along with other key climate indicators. We are concerned with recent trend of increase of methane concentration in the atmosphere. Therefore WMO warmly welcomes the Methane pledge and we are pleased to see so many CCAC members making strong contributions,” said Dr Manaenkova.

“WMO develops technical standards for observational based emission estimates (through the Integrated Global Greenhouse Gas Information System (IG3IS)). We have the tools and methodology to help develop the most efficient emission mitigation strategies to realize  Methane pledges and to quantify achieved results,” she said.

“The instrumental observations can help you locate known and unknown emission sources and identify emission reduction opportunities. WMO is happy to offer guidance and assistance and stands ready to help,” said Dr Manaenkova.

Methane accounts for about 16% of the warming effect of long-lived greenhouse gases since pre-industrial time, according to the US National Oceanic and Atmospheric Administration (NOAA). Approximately 40% of methane is emitted into the atmosphere by natural sources (for example, wetlands and termites), and about 60% comes from anthropogenic sources (for example, ruminants, rice agriculture, fossil fuel exploitation, landfills and biomass burning).

The increase in the globally averaged annual methane concentration from 2019 to 2020 was higher than 2018 to 2019 and also higher than the average annual growth rate over the last decade, according to the WMO’s Greenhouse Gas Bulletin.