<div data-thumb=”https://scx1.b-cdn.net/csz/news/tmb/2023/rising-methane-could-b.jpg” data-src=”https://scx2.b-cdn.net/gfx/news/hires/2023/rising-methane-could-b.jpg” data-sub-html=”Soaring wetland emissions of methane reflect those which accompanied previous abrupt changes in Earth’s climate. Credit: I. Noyan Yilmaz/Shutterstock“>
Soaring wetland emissions of methane reflect those which accompanied previous abrupt changes in Earth’s climate. Credit: I. Noyan Yilmaz/Shutterstock
Since 2006, the amount of heat-trapping methane in Earth’s atmosphere has been rising fast and, unlike the rise in carbon dioxide (CO₂), methane’s recent increase seems to be driven by biological emissions, not the burning of fossil fuels. This might just be ordinary variability—a result of natural climate cycles such as El Niño. Or it may signal that a great transition in Earth’s climate has begun.
Molecule for molecule, methane is a much more potent greenhouse gas than CO₂ but it lasts slightly less than a decade in the atmosphere compared with centuries for CO₂. Methane emissions threaten humanity’s ability to limit warming to relatively safe levels. Even more troubling, the rate at which methane is increasing in the atmosphere has accelerated recently. Something like this has happened before: sudden surges in methane marked the transitions from cold ice ages to warm interglacial climates.
Methane was about 0.7 parts per million (ppm) of the air before humans began burning fossil fuels. Now it is over 1.9 ppm and rising fast. Roughly three-fifths of emissions come from fossil fuel use, farming, landfills and waste. The remainder is from natural sources, especially vegetation rotting in tropical and northern wetlands.
Methane is both a driver and a messenger of climate change. We don’t know why it is now rising so rapidly, but the pattern of growth since late 2006 resembles how methane behaved during great flips in Earth’s climate in the distant past.
The methane record: 2006 to present
In late 2006, atmospheric methane unexpectedly began rising. Methane had risen fast in the 19th and 20th centuries but plateaued by the end of the 1990s. This rise was driven by fossil fuel emissions, especially from gasfields and coal mines.
Imagine accelerating a car with your foot flat down. The car speeds up but eventually air resistance equals engine power and the car hits maximum speed. In 1999, it looked like methane had reached a similar equilibrium between its sources and sinks. Then in late 2006, the amount of methane in the air climbed fast. Even more unexpectedly five years later, the rate of growth sped up again. During the 2020s the growth rate has become yet faster, faster even than during the peak of gas industry leaks in the 1980s.
Today’s growth seems to be driven by new emissions from wetlands, especially near the equator but perhaps also from Canada (beavers are methane factories which pull huge amounts of plant matter into ponds they’ve made) and Siberia. This is a result of climate change: increasing rainfall has made wetlands wetter and bigger while rising temperatures have boosted plant growth, providing more decomposing matter and so more methane. Emissions from huge cattle lots in tropical Africa, India and Brazil may also be rising and rotting waste in landfills near megacities like Delhi are important sources too.
<div data-thumb=”https://scx1.b-cdn.net/csz/news/tmb/2023/rising-methane-could-b-1.jpg” data-src=”https://scx2.b-cdn.net/gfx/news/2023/rising-methane-could-b-1.jpg” data-sub-html=”Methane in the air rose rapidly from 2006—then it rose again, and again. Credit: NOAA/Nisbet et al. (2023), Author provided”>
Methane in the air rose rapidly from 2006—then it rose again, and again. Credit: NOAA/Nisbet et al. (2023), Author provided
Climate terminations
In the past few million years, Earth’s climate has flipped repeatedly between long, cold glacial periods, with ice sheets covering northern Europe and Canada, and shorter warm inter-glacials.
When each ice age ended, Earth’s surface warmed by as much as several degrees centigrade over a few millennia. Recorded in air bubbles in ice cores, sharply rising methane concentrations are the bellwethers of these great climate-warming events. With each flip from a glacial to an interglacial climate there have been sudden, sharp rises in atmospheric methane, likely from expanding tropical wetlands.
These great climate flips that ended each ice age are known as terminations. Each has a Roman numeral, ranging from Termination IX which happened about 800,000 years ago to Termination IA which initiated the modern climate less than 12,000 years ago. For example, around 131,000 years ago during Termination II, the British climate suddenly flipped from glaciers in the Cotswolds to hippopotami wallowing in what is now Trafalgar Square.
Full terminations take several thousands of years to complete, but many include a creeping onset of warming, then a very abrupt phase of extremely rapid climate change that can take a century or less, followed by a longer, slower period during which the great ice caps finally melt. In the abrupt phase of the great change that brought about the modern climate, Greenland’s temperature rose by around 10°C within a few decades. During these abrupt phases, methane climbs very steeply indeed.
Is something dramatic underway?
Methane fluctuated widely in pre-industrial times. But its increasingly rapid growth since 2006 is comparable with records of methane from the early years of abrupt phases of past termination events, like the one that warmed Greenland so dramatically less than 12,000 years ago.
There is already lots of evidence that the climate is shifting. Atlantic ocean currents are slowing, tropical weather regions are expanding, the far north and south are warming fast, ocean heat is breaking records and extreme weather is becoming routine.
In glacial terminations, the entire climate system reorganizes. In the past, this took Earth out of stable ice age climates and into warm inter-glacials. But we are already in a warm interglacial. What comes next is hard to imagine: loss of sea ice in the Arctic in summer, thinning or partial collapse of the ice caps in Greenland and West Antarctica, reorganization of the Atlantic’s ocean currents and the poleward expansion of tropical weather circulation patterns. The consequences, both for the biosphere in general and food production in south and east Asia and parts of Africa in particular, would be very significant.
There’s much to be done that could hastily stop methane’s rise: plugging leaks in the oil and gas industry, covering landfills with soil, reducing crop-waste burning. Shooting the methane messenger won’t stop climate change, which is primarily driven by CO₂ emissions, but it will help.
Roman numerals IX to I denote past great climate transitions. There is no Roman number zero, but then any future termination-scale transition will be different—a temperature step from our present interglacial climate to some new future that is warmer yet. Methane’s signal is still unclear, but the question remains: has Termination Zero begun?
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Rising methane could be a sign that Earth’s climate is part way through a ‘termination-level transition’ (2023, August 15)
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NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.
Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.
She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.
Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.
“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.
It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.
Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.
Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.
Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.
“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.
He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.
Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.
TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.
Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.
Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.
The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.
The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.
It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.
Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.
Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.
Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.
Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.
Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.
The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”
VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.
Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”
Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.
“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.
B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.
Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.
Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.
Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.
“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”
Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”
“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.
Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.
“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.
This report by The Canadian Press was first published Sept. 9, 2024.
