BAKU: Research reveals that tropical wetlands are releasing record-breaking levels of methane, a development that poses significant challenges to global climate objectives. The surge, unaccounted for in many national emissions plans and underrepresented in scientific models, could pressure governments to implement stricter emissions cuts in fossil fuel and agriculture sectors.
Wetlands naturally store vast amounts of carbon in decaying plant matter, but rising temperatures accelerate microbial processes that produce methane. Additionally, heavy rainfall triggers flooding, expanding wetland areas and further increasing emissions.
Scientists had long anticipated that wetland methane emissions would rise with global warming. However, from 2020 to 2022, atmospheric samples revealed the highest methane concentrations since records began in the 1980s. Recent studies attribute the spike primarily to tropical wetlands, with regions such as the Congo, Southeast Asia, the Amazon, and southern Brazil identified as key contributors.
According to Stanford University’s Rob Jackson, chair of the Global Methane Budget, “Methane concentrations are not just rising but are increasing faster in the last five years than any time in recorded history.” Satellite data pinpointed the tropics as the source, and chemical analyses confirmed wetlands as the primary emitter.
A 2023 Nature Climate Change study showed that wetland emissions over the past two decades exceeded worst-case scenario projections by about 500,000 tonnes annually. These findings underscore the difficulty of capturing wetland emissions using current technologies. Climate scientist Drew Shindell of Duke University remarked, “We should probably be a bit more worried than we are.”
The La Niña weather pattern, which ended in 2023, contributed to increased rainfall and emissions but doesn’t fully explain the record highs. Atmospheric chemist Zhen Qu from North Carolina State University emphasized the implications for governments aiming to meet Paris Agreement targets, highlighting the need for more robust action.
Methane’s Climate Impact
Methane is 80 times more potent than carbon dioxide at trapping heat over 20 years and accounts for about one-third of the 1.3°C global warming since 1850. Unlike CO2, methane has a shorter atmospheric lifespan of about a decade, making immediate reductions crucial for near-term climate mitigation.
Over 150 countries have pledged to cut methane emissions by 30% from 2020 levels by 2030, focusing on curbing leaks in oil and gas infrastructure. Despite these commitments, emissions from fossil fuels remain at record highs of around 120 million tonnes annually, according to the International Energy Agency’s 2024 Global Methane Tracker.
Satellites have detected more than 1,000 significant methane plumes from oil and gas operations in the past two years, but only 12 leaks have been addressed by governments, per a U.N. Environment Programme report. Ambitious measures, such as China’s efforts to limit flaring and the U.S.’s recently finalized methane fee for large oil and gas producers, face political uncertainties.
Congo Basin Methane Hotspot
The Democratic Republic of Congo (DRC) is a major contributor to tropical methane emissions, according to the 2024 Global Methane Budget. Environment Minister Eve Bazaiba noted at COP29 that the country is working to assess and monitor methane emissions from its vast wetlands. “We don’t know how much methane is being released,” she said. “We need investment and expertise to conduct inventories and explore sustainable solutions.”
The Road Ahead
If tropical wetland methane emissions continue to rise, scientists warn that achieving the 1.5°C warming target set by the Paris Agreement will require stronger and more immediate actions globally. The findings highlight the urgent need for innovative strategies to address methane emissions while adapting to the evolving challenges of a warming planet.
