Soaring methane levels threaten climate ambitions
2024-09-27
| Policy Research and Advocacy Team, Friends of the Earth (HK)
Launched at COP26 in 2021, the Global Methane Pledge has now been
joined by 158 countries. These nations, representing over 50% of global methane
emissions, are committed to collectively reducing methane emissions by at least
30% from 2020 levels by 2030.[1]
The Global Methane Pledge
is joined by 158 countries (in blue), accounting for over 50% of methane
emissions globally (Image source: Global Methane Pledge)
Methane is the second most important greenhouse gas—after carbon
dioxide—being responsible for 20-30% of global warming. Because methane has a
stronger warming effect over a shorter period of time, making deep cuts to this
short-lived climate pollutant would help limit near-term warming and buy time
for reducing carbon dioxide.[2] Recent
report however suggests that methane emissions are rising faster than ever.
Scientists under the Global Carbon Project found that annual methane
emissions increased by 15-20% over the past two decades.[3] At
least two-thirds come from human activities, such as cattle rearing (and other
ruminants), rice paddies, coal mining, natural gas extraction and transport,
and organic waste decomposing in landfills. While European nations have begun
reducing methane emissions, China, India, and the US remain major emitting
countries.
Replacing coal with natural
gas (methane) in electricity generation has become a major part of Hong Kong’s
midterm decarbonisation strategy (Image source: HK Electric)
The study also found wetlands and waterlogged soils—which account
for the remaining third of methane emissions—are becoming climate bombs, as
rising temperatures threaten to convert these major carbon sinks into emitters.[4]
Warming climate and thawing
permafrost releases methane from wetlands—sometimes explosively like Siberia’s
exploding craters (Image source: Aleksandr Lutcenko/Shutterstock)
Atmospheric methane levels are now 2.6 times higher than in
pre-industrial times, and have been rising more rapidly in the past few years. The
current trend not only threatens the Global Methane Pledge, but also puts the
world on track for at least 3°C of warming
by the end of the century. Rampant methane emissions pose other problems too.
Methane is a major source of ground-level ozone, a toxic pollutant that can
trigger a range of health problems in humans and animals, such as coughing,
shortness of breath, and asthma attacks.[5]Ozone pollution also damages plants, leading to crop losses.[6]
The silver lining is that there are solutions to cut methane
emissions right now. The oil and gas sector could address a significant portion
of its emissions by avoiding routine venting and repairing leaks.[7] Besides
phasing out coal consumption outright, degasification systems can capture
methane emissions during coal mining operations.[8] In
food production, planting low-methane rice varieties and adopting best
practices can address emissions in rice cultivation;[9]feed additives can reduce cow belching and flatulence;[10] a
shift towards plant-based diets would also directly cut demand on red meats and
cattle rearing.
Adding seaweed to feed
could make cows less gassy, but eating less meat would address agricultural
methane emissions more directly (Image source: Shutterstock)
We have just a bit over five years before 2030, when emissions
should be cut by almost half to limit global warming to 1.5°C. We must accelerate efforts to slash methane emissions if we want to
still have a liveable planet.