It seems we've been "fudging the numbers" in a sense, when comparing the global warming potential of methane to CO2. When global warming potential (GWP) of a gas is calculated, a time frame is assumed. The IPCC decided to use a 100 year time frame.
With a 100 year time frame methane heats up the planet 21 times as much as CO2. The problem with that assumption is that we don't have 100 years. A 20 year time frame would be much more realistic, given the urgency of climate crisis. With a 20 year time frame...
... any CH4 released today is at least 56 times more heat-trapping than a molecule of C02 also released today. And because of the way it reacts in the atmosphere, the number is probably even higher, according to research conducted by Drew Shindell , a scientist at NASA’s Goddard Space Center. [emphasis mine]
What if we were to use the IPCC’s 20-year comparison instead of its 100-year comparison? For starters, it would force us to get much more serious about tackling the sources of methane emissions. Here in the US, the top methane sources are the decomposition of wastes in landfills, agriculture (from ruminant digestion), and leaks from natural gas drilling and transmission. A new emphasis on methane would require us to get smarter about capturing methane at landfills, reduce the market incentives that encourage Americans’ meat-heavy diets, and ensure that methane isn’t leaking from fracking operations.
But beyond the policy specifics, adopting the 20-year global warming potential comparisons would be useful for changing how we think about climate change.
And we appear to be approaching some irrevocable tipping points that will create powerful negative feedback loops, the most worrisome being the release of methane stores at the bottom of the ocean and locked into sub-Arctic permafrost.
Image from Arctic Methane Release Tipping Point Diagram
With 56 times as much warming as CO2 in mind, we'd take this feedback more seriously.
That 28% statistic about the contribution of CH4 does not include water vapor, whose effect vastly outweighs all other greenhouse gases, but is hard to quanitfy because its concentration is highly variable and doesn't "decay" from the atmosphere in the traditional sense.
There is a reason why the Earth did not in fact become Venus at times like the Paleocene-Eocene Thermal Maximum, when there must have been no permafrost in the Arctic. It will still get pretty bad though.
When I read estimates like this of how delicate is the stability of our planet's habitability, I feel as if scientists are like a Dad, telling his 3-year old son not to touch the blowtorch trigger in his hand, and 99.9% of adults are ignoring a warning they don't comprehend like that about-to-immolate himself kid.
Ruth, you provide us with a vivid image of your feelings. There are still those who do not understand how serious this is. The child imbeded in these flames clearly shows terror, too late. The father and the scientists speaks from knowledge; people don't hear, or don't care, or don't understand the significance before the explosion.
My guess is our soils and forest will dry up as will the grasslands and all make fine material for fire. We have a new one brewing just north of us in British Columbia.
Update on methane craters.
It seems only the pingos on the Yamal and Taimyr peninsulas explode, and sometimes erupt into flames. This is the first I'd heard that Gazprom punctures pingos to release methane, to avoid explosions.
He believes that the phenomenon is 'unique' the geological conditions on the Yamal and Taimyr peninsulas, where. 'We now know that these objects form when there is a coincidence of a thick layer of permafrost and thick sedimentary cover of 3.5 to 5 kilometres,' he said.
'This is why we can observe pingos in Yakutia or Alaska, but they do not explode.'
Such 'degassing' is happening in many locations but uneven thawing in permafrost regions means methane is not released evenly and can collect in pockets, eventually exploding.
'Strong degassing is occurring in the Arctic,' he said.
'But what we have just seen is a drop in the ocean of this global degassing of subsoil.'
'I know that oil and gas producing companies have maps of such objects and monitor them constantly.
'I have heard that for example Gazprom-Dobycha Yamburg make punctures and release gas to avoid eruption risk.
'When I was working at VNIIGAZ, I made a map of such objects for Gazprom.'
He said: 'The companies are very interested in minimising risks, they do not need any accidents, so they make maps and observe these objects very closely.
A second new crater - also formed this year - was created after an explosion on bulging ground around 500 km north of the town of Salekhard.
'This plot of land was absolutely flat just two years ago,' he said.
'A year ago in 2016 it bulged and we could see that soil has cracked there.'
Thanks for the update!
What's Gazprom's / Russia's official line on climate change? We know that US fossil fuel companies have been manufacturing doubt for decades (just like tobacco companies did with lung cancer and other dangers of smoking) at the same time that they recognized reality by, for instance, raising their offshore drilling platforms.
We may be grossly under-accounting for methane in our existing climate models.
We thought that all methane-generating microbes required anaerobic conditions. Enter Candidatus Methanothrix paradoxum.
... 80 percent of the methane in the wetland under study came from oxygenated soils. The microbe’s habitat extends from the deepest parts of a wetland, which are devoid of oxygen, all the way to surface soils.
“We’ve always assumed that oxygen was toxic to all methanogens,” said Kelly Wrighton, project leader and professor of microbiology at Ohio State. “That assumption is so far entrenched in our thinking that global climate models simply don’t allow for methane production in the presence of oxygen. Our work shows that this way of thinking is outdated, and we may be grossly under-accounting for methane in our existing climate models.”
"The researchers found traces of Candidatus Methanothrix paradoxum in more than 100 sites across North America, South America, Europe and Asia. The organism lives in rice paddies, wetlands and peatlands—even as far north as the Arctic. It just hadn’t been cataloged before, and its unusual metabolism hadn’t been discovered."
A new study of Lake Hallwil discovered a new, overlooked, methane-production phenomenon. Instead of coming from anaerobic bottom sediment, 90% of methane produced was coming from the oxygen-rich well-mixed top 5 meters. So far they're not exactly sure of the mechanism, offering several hypotheses.
Lakes and freshwater systems account for over 20% of all methane emissions into the atmosphere – much more than previously estimated, according to scientists at the University of Geneva
“Something huge is going on in the surface water, and nobody has been paying attention to it so far,” said study co-author Daniel McGinnis. A similar phenomenon has been reported in the surface of the oceans but on a smaller scale, about 1,000 times lower. [emphasis mine]
Stirring up the methane in Lake Hallwil
Wildfires have been going down globally, it seems, despite the recent fires in North America, Europe, and Russia, because agriculture replaced wild lands. And since fires release methane, the decrease has masked increases from other sources.
The area of the planet burned each year decreased by about 12% between the early 2000s and the more recent period of 2007 to 2014, according to satellite observations.
Dr Worden’s team calculates that 17 teragrams per year of the methane increase in the atmosphere is due to fossil fuels, another 12 is coming from wetlands or rice farming, while fires are decreasing by about 4 teragrams per year.
The three numbers combine to 25 teragrams a year – the same as the observed increase.
Mars Today - A 'Business-As-Usual' Model for Earth Tomorrow
Dr. David Page claims that East Siberian Arctic Shelf models, which predict low probability of large scale release on Earth, "show little correspondence with reality." Geological evidence of a degassing event on Mars suggests that volatile gas reservoirs can undergo rapid emptying when a pressure or temperature threshold is crossed.
Mound explosions on Mars and Earth. Main) Dense cluster of exploded mounds at martian
equator, composite haloes around individual clusters indicating synchronous blasts.
Explosions traceable continuously for 100s-of-km.
The 'plan-view' of the martian event exposed at the surface shows one explosion communicated to another and another, with mutual interference of blast-waves evident throughout. In this explosive degassing over 100s-of-km, Mars shows that once explosion begins it spreads, with local- to regional-scale synchrony.
Dr Page criticizes in particular a 2015 paper by Archer which downplays Shakova's prediction of a 50 gigaton release from the East Siberian Arctic Shelf. Archer omits mechanisms of gas release, then says the model gives no indication of such mechanims. Moreover the model's predicted methane flux has already been surpassed by actual readings 200 times higher.
In questioning the abrupt 50 Gt Arctic-methane release proposed by Shakhova et al. (2010), Archer says that "...A complex model is not really required to conclude that methane hydrate will probably not produce a methane eruption of this scale so quickly". Yet models (particularly the complex ones) are only as good as their base assumptions, and that regarding the methane flux in this region shows little correspondence with reality. There is thus no support for the Conclusion that "...The model results give no indication of a mechanism by which methane emissions from the Siberian continental shelf could have a significant impact on the near-term evolution of Earth’s climate" as the geological discontinuities that should be foremost in that mechanism are omitted from the model and the long-term CH₄-flux predictions of that model have no bearing to current, observed methane flux.
... devolatilisation appears to be limited only by volatile availability and to run to completion once initiated. As such, the proposed < 5% (50 Gt) release from ESAS may be highly conservative. [emphasis mine]
In short, just because previous interglacials did not support the methane gun hypothesis, doesn't mean it's invalid. Previous interglacials were followed by re-glaciation before a Mars-like degassing event could be triggered. This time humans have already delayed that at least a thousand years, our danger is real, and Shakhova's warning is "highly conservative".
In other news, ESAS permafrost melting up to 18 cm/yr.
According to the model estimates of the Intergovernmental Panel on Climate Change (IPCC), until the end of the 21st century the degradation of permafrost in the ESAS cannot exceed several meters and the formation of through taliks will take hundreds or thousands of years that eliminates the opportunity of massive methane (CH4) emissions from the bottom sediments of the ESAS into water column - atmosphere system due to the destruction of hydrates. Thus the IPCC considers the potential contribution of the ESAS into the emissions of CH4 as insignificant. The paper shows that the model is not really correct. Basing on the repeated drilling of four wells performed by the Institute of Permafrost Siberian Branch of Russian Academy of Sciences in 1982-1983, scientists have proved that the rates of vertical degradation of subsea permafrost amount to 18 cm a year over the last 30 years (the average is 14 cm a year) which is greater than it was assumed before.'New data obtained by complex biochemical, geophysical and geological studies conducted in 2011-2016 resulted in the conclusion that in some areas of the East Siberian Arctic Shelf the roof of the subsea permafrost had already reached the depth of hydrates' stability the destruction of which may cause massive releases of bubble methane.' [emphasis mine]
Aquatic Ecosystem Ecologist Katey Walter Anthony, introduces a new Arctic lake phenomenon -- Esieh Lake emits methane much faster.
Esieh Lake is one of several lakes scattered across the Arctic that never fully freezes due to its emission of methane gas from its lake bottom. After investigating the source of the methane, Anthony's team found that the source wasn't the soil, it was caches of fossil fuels—ancient organic material.
..., the continued growth of lakes like Esieh could double the amount of greenhouse gases coming from the Arctic by 2100.
Esieh Lake looks different from thermokarst lakes, emitting gases faster.
Set against the austere peaks of the Western Brooks Range, the lake, about 20 football fields in size, looked as if it was boiling. Its waters hissed, bubbled and popped as a powerful greenhouse gas escaped from the lake bed. Some bubbles grew as big as grapefruits, visibly lifting the water’s surface several inches and carrying up bits of mud from below. This was methane. [emphasis mine]