Impacts of potent greenhouse gas: a bit lower than previously thought.
UC Riverside researchers found that methane not only traps heat in the atmosphere but also creates cooling clouds that offset 30% of the heat. Methane’s absorption of shortwave energy counterintuitively causes a cooling effect and suppresses the increase in precipitation by 60%. This finding emphasizes the need to incorporate all known effects of greenhouse gases into climate models.
Most climate models do not yet account for a new University of California, Riverside discovery: methane traps a great deal of heat in Earth’s atmosphere, but also creates cooling clouds that offset 30% of the heat.
Greenhouse gases like methane create a kind of blanket in the atmosphere, trapping heat from Earth’s surface, called longwave energy, and preventing it from radiating out into space. This makes the planet hotter.
“A blanket doesn’t create heat, unless it’s electric. You feel warm because the blanket inhibits your body’s ability to send its heat into the air. This is the same concept,” explained Robert Allen, UCR assistant professor of Earth sciences.
In addition to absorbing longwave energy, it turns out methane also absorbs incoming energy from the sun, known as shortwave energy. “This should warm the planet,” said Allen, who led the research project. “But counterintuitively, the shortwave absorption encourages changes in clouds that have a slight cooling effect.”
This effect is detailed in the journal Nature Geoscience, alongside a second finding that the research team did not fully expect. Though methane generally increases the amount of precipitation, accounting for the absorption of shortwave energy suppresses that increase by 60%.
Both types of energy — longwave (from Earth) and shortwave (from sun) — escape from the atmosphere more than they are absorbed into it. The atmosphere needs compensation for the escaped energy, which it gets from heat created as water vapor condenses into rain, snow, sleet, or hail.
“Essentially, precipitation acts as a heat source, making sure the atmosphere maintains a balance of energy,” said study co-author Ryan Kramer, a researcher at NASA Goddard Space Flight Center and the University of Maryland, Baltimore County.
Methane changes this equation. By holding on to energy from the sun, methane is introducing heat the atmosphere no longer needs to get from precipitation.
Additionally, methane shortwave absorption decreases the amount of solar radiation reaching Earth’s surface. This in turn reduces the amount of water that evaporates. Generally, precipitation and evaporation are equal, so a decrease in evaporation leads to a decrease in precipitation.
“This has implications for understanding in more detail how methane and perhaps other greenhouses gases can impact the climate system,” Allen said. “Shortwave absorption softens the overall warming and rain-increasing effects but does not eradicate them at all.”
The research team discovered these findings by creating detailed computer models simulating both longwave and shortwave methane effects. Going forward, they would like to conduct additional experiments to learn how different concentrations of methane would impact the climate.
Scientific interest in methane has increased in recent years as levels of emissions have increased. Much comes from industrial sources, as well as from agricultural activities and landfill. Methane emissions are also likely to increase as frozen ground underlying the Arctic begins to thaw.
“It’s become a major concern,” said Xueying Zhao, UCR Earth and planetary sciences Ph.D. student and study co-author. “We need to better understand the effects all this methane will bring us by incorporating all known effects into our climate models.”
Kramer echoes the need for further study. “We’re good at measuring the concentration of greenhouse gases like methane in the atmosphere. Now the goal is to say with as much confidence as possible what those numbers mean to us. Work like this gets us toward that goal,” he said.
Reference: “Surface warming and wetting due to methane’s long-wave radiative effects muted by short-wave absorption” by Robert J. Allen, Xueying Zhao, Cynthia A. Randles, Ryan J. Kramer, Bjørn H. Samset and Christopher J. Smith, 16 March 2023, Nature Geoscience.
I hope this will humble the “climate crisis” people; you don’t know how the planet works, you don’t know how we’re changing it, and you certainly don’t know the impacts of what you’re advocating to address those changes. Nobody knows these things, but we’re learning, and hoping to reduce those changes. So, methane emissions are maybe half as much a problem as we thought, if it is a problem. Given the limitations to our knowledge of planetary systems, it’s not a shock. I doubt this will bring any humility to the certainty climate activists show, as it seems to come from faith in a new nature-religion, but we can hope.
you have it all wrong. The people you hate are simply saying, “stop destroying the earth for profit. We like our planet the way it was before the destruction began.”
I don’t hate these people. If only that were all they were saying. I profoundly disagree with them, but their intense self-confidence leads to zeal and authoritarian force. The idea that the planet will be destroyed would justify doing anything and everything, potentially unleashing horrors in the name of an apocalyptic religion. If preventing the destruction of earth to save infinite generations of people in the future means only billions of people have to die tomorrow…the certainty is toxic.
Furthermore, the commonly-quoted global warming potential multipliers (32X & 85X), for the conversion of atmospheric methane concentration into a CO2 warming equivalence, are overstated by a factor of about 2.75X. That means,the long-term warming potential for methane should be about 12X rather than the usually cited 32X.
If you hear anyone say that “The science is settled,” you should seriously question everything else that they say.
What are Mr. Spencer’s qualifications in climate science in order to question how the IPCC accounts for the warming effect of methane? If Google serves me right, an M.S. in geology back when climate change wasn’t researched or taught?
And what are your qualifications for challenging my qualifications? For what it is worth, my academic background isn’t all that different from Michael Mann, who doesn’t have any degrees that mention climatology. My undergraduate emphasis was in geophysics. I have been issued a patent in the field of remote sensing, which I became an expert in before degrees were offered in the field. I think that you are too concerned about academic qualifications.
Just for the record, Exxon has been accused of knowing all about Climate Change during the period of time that you claim that it wasn’t being researched. Which is it?
The way that science works is that an argument is supposed to stand on its own merits, not on who came up with an idea. There are numerous examples where someone with ‘unchallengeable’ credentials got things wrong — most notably, when Lord Kelvin got the age of the Earth very wrong. If you can point out any errors in my article at the link I provided, I would be very appreciative. That is how peer review is supposed to work. I await your substantive critique.
It’s just the appeal to authority fallacy. But geophys, fantastic. I enjoy your comments here, and no wonder they focus on earth science articles. I just like the pretty photos remote sensing generates. The best is the ground-penetrating radar, like on Time Team, but they need to make those things cheaper as autonomous robots, maybe add a spinning blade. I could find a Roman coin horde and mow the lawn too from my armchair.
Mr. Moffet, I’m still waiting on your critique of my claims.
Let’s still proceed with replacing the natural gas furnaces with the noisy and inefficient heat pumps. Let’s replace the gas water heaters with the electric ones while our electric grid is overloaded and unreliable. Let’s replace the gas stoves with the induction ones because the manufacturers say the EMF those stoves produce is not dangerous.
Let’s do all that because we know that the methane plays the crucial role in the global warming, right? Right?
These comments are cute, “So, methane emissions are maybe half as much a problem as we thought, if it is a problem.” They stated 30% is blocked so how is that half or no problem?
“If you hear anyone say that “The science is settled,” you should seriously question everything else that they say.” This mentality leads people to not believe in science because someone didn’t get all the information right which is a horribly misguided attempt to disprove reality. “Let’s still proceed with replacing the natural gas furnaces with the noisy and inefficient heat pumps.” LOL heat pumps are nearly silent now a days and if they have a c.o.p. of 3 which is common you are getting 3 units of heat out for every one put in, so three times as efficient as electric resistance heaters, that goes for heat pump water heaters as well. And right I agree.
“This mentality leads people to not believe in science because someone didn’t get all the information right which is a horribly misguided attempt to disprove reality.”
Science is a process, indeed, what is usually referred to as the Scientific Method. More than 100 years after Einstein’s theories were presented, other scientists are still trying to prove them wrong. I don’t think that you really understand science. Science isn’t a list of commandments chiseled in stone tablets. It is a search for understanding how things work, and the ability to predict how a system will react to a perturbation.
The belief that people need to have is that the process of science works, not that the current paradigm is the end of the search.
Actually, the article stated methane “creates cooling clouds that offset 30% of the heat. Methane’s absorption of shortwave energy counterintuitively causes a cooling effect and suppresses the increase in precipitation by 60%”. These are very round estimates for shortwave-energy only of unforeseen and previously unstudied effects, so I gave a rougher one offhand. There’s the quote in any case. If this one study slashed the number for methane’s effects with something so basic as what clouds do, the next study might show how methane emissions are actually no problem at all, or even beneficial. Or, much worse of a problem than before this study eased our fears. Or maybe it just corroborate this study’s conclusions. We don’t know.
Consider researching the philosophy of science. Whether or not people will believe in science is irrelevant; ‘the science’ is never settled. I believe the foundation of knowledge is first understanding our own ignorance, and the foundation of science is questioning. The closest you can get to certainty in science is maybe laws of physics, but they’re our laws for physics, and sometimes physics defies them, so our laws for physics get revised and refined. It’s difficult coming to grips with the ignorance and uncertainties of science, but I found that once I did, it strengthened my belief in the scientific process and revealed its awesome capabilities.
No need to tell us that science is a journey. Tell that to legislators who are quick to make laws from at every turn of the road.
We can easily end global warming if we all stop flying jets planes and rockets of all kinds and go back to flying only propeller airplanes only. Read my website at solutionstoglobalwarming.com and let me explain to all of you just what caused global warming and how to end global warming. We CAN do many things to help Mother Nature to stop global warming and many things we can do to rebuild our ice on Earth as well as making our planets waters colder. I am having exchanges with the chatGPT to prove that I am right in everything that I say.
Silent heat pumps? I guess my two neighbors who recently installed heat pumps did not get the memo. Those things whine all night. In summer, you don’t want to have a bedroom window open. In winter, on a cold nights you can hear them even with the windows closed.
so cows emit cycle able methane, so no trouble at all then, just been used as a scapegoat so we can continue to use fossil fuels and pretend we have sorted the problem. When in fact cows are locking up carbon in the grasslands they graze. What a con ,being led by a vegan mindset, not science.
Depending on who you ask, well-managed grazing might sequester carbon. If not well-managed, probably the opposite. Grazing is only a minority of their food anyway.