3 ms·

Isn't methane much more of an offender than CO2?

by briefcomment 5y ago

Sebguer 5y ago
Methane decays relatively rapidly.
- ben_w 5y ago
  Relatively quickly, but it’s also really potent. 25-36 times worse over the first century, despite the decay period of 12 years: https://www.epa.gov/ghgemissions/understanding-global-warming-potentials https://www.epa.gov/ghgemissions/understanding-global-warmin... (Note that while linked page says 28-36, another page on the same site says 25).
w-j-w 5y ago
Per pound, methane is much worse for the climate. We produce way more CO2 though.
thinkcontext 5y ago
No, co2 is bigger by quite a bit. Methane is increasing rapidly which is a big concern because of potential feedback effects. https://en.m.wikipedia.org/wiki/Greenhouse_gas https://en.m.wikipedia.org/wiki/Greenhouse_gas
ArnoVW 5y ago
One molecule of methane is worse than one molecule of CO2. But there is more CO2 than there is methane, so the total 'warming' by CO2 is worse.
- nverno 5y ago
  Except we've already reached higher saturation (for black body radiation absorption) with CO2 than with methane. So, there is certainly a strong case to be made that methane is more impactful in the short-term than CO2 in terms of climate warming.
  - lucb1e 5y ago
    I haven't heard that before and it sounds conceptually incompatible with generally accepted concepts like the globally remaining CO2 budget (how could we have a budget, if we've already reached the CO2 saturation point and adding more doesn't worsen the problem?). Do you have a source for this?
    - nverno 5y ago
      Well the climate never becomes completely insensitive to further increases in CO2 concetration - lookup the band saturation effect. I wasn't citing a specific source, only pointing out that different gases absorb at different wavelengths, some of which (like methane) have potential to absorb much more with increasing concentration. IIRCC there are other factors, like the persistence time in the atmosphere, that make CO2 more worrysome. I took this edx course on climate modeling a few years ago that was fantastic if you want to dig deeper and the professor does cover these topics (which I'm likely butchering) - https://courses.edx.org/courses/UChicagoX/PS280x/2015_T1/course/ https://courses.edx.org/courses/UChicagoX/PS280x/2015_T1/cou...

Isn't methane much more of an offender than CO2?

Sebguer 5y ago

Methane decays relatively rapidly.

ben_w 5y ago
Relatively quickly, but it’s also really potent. 25-36 times worse over the first century, despite the decay period of 12 years: https://www.epa.gov/ghgemissions/understanding-global-warming-potentials https://www.epa.gov/ghgemissions/understanding-global-warmin... (Note that while linked page says 28-36, another page on the same site says 25).

w-j-w 5y ago

Per pound, methane is much worse for the climate. We produce way more CO2 though.

thinkcontext 5y ago

No, co2 is bigger by quite a bit. Methane is increasing rapidly which is a big concern because of potential feedback effects. https://en.m.wikipedia.org/wiki/Greenhouse_gas https://en.m.wikipedia.org/wiki/Greenhouse_gas

ArnoVW 5y ago

One molecule of methane is worse than one molecule of CO2. But there is more CO2 than there is methane, so the total 'warming' by CO2 is worse.

nverno 5y ago
Except we've already reached higher saturation (for black body radiation absorption) with CO2 than with methane. So, there is certainly a strong case to be made that methane is more impactful in the short-term than CO2 in terms of climate warming.
- lucb1e 5y ago
  I haven't heard that before and it sounds conceptually incompatible with generally accepted concepts like the globally remaining CO2 budget (how could we have a budget, if we've already reached the CO2 saturation point and adding more doesn't worsen the problem?). Do you have a source for this?
  - nverno 5y ago
    Well the climate never becomes completely insensitive to further increases in CO2 concetration - lookup the band saturation effect. I wasn't citing a specific source, only pointing out that different gases absorb at different wavelengths, some of which (like methane) have potential to absorb much more with increasing concentration. IIRCC there are other factors, like the persistence time in the atmosphere, that make CO2 more worrysome. I took this edx course on climate modeling a few years ago that was fantastic if you want to dig deeper and the professor does cover these topics (which I'm likely butchering) - https://courses.edx.org/courses/UChicagoX/PS280x/2015_T1/course/ https://courses.edx.org/courses/UChicagoX/PS280x/2015_T1/cou...