4 ms·
A bit of clarification on which oxides, from the article: By burning heavy fuel oil, just 15 of the biggest ships emit more oxides of nitrogen and sulphur—gases
by anonu 10y ago
A bit of clarification on which oxides, from the article: By burning heavy fuel oil, just 15 of the biggest ships emit more oxides of nitrogen and sulphur—gases much worse for global warming than carbon dioxide—than all the world’s cars put together
- mikeash 10y ago"gases much worse for global warming than carbon dioxide" Do you have a source on that? My understanding was that they are short lived and block heat rather than retain it.
- djsumdog 10y agoWell he was quoting the article, so you're really asking if the Economist has a source for that.
- mikeash 10y agoLooks like a combination of false and misleading. Perusing Wikipedia's list of gases: https://en.wikipedia.org/wiki/Greenhouse_gas#Global_warming_potential https://en.wikipedia.org/wiki/Greenhouse_gas#Global_warming_... The only listed oxides are CO2 and N2O. N2O does indeed have much greater potential than CO2, but its concentration in the atmosphere is only 270ppb, which is 20% over preindustrial levels, so its overall contribution is negligible.
- mrkurt 10y agoNot false. The EPA quotes that "300x worse" number directly: https://www.epa.gov/ghgemissions/overview-greenhouse-gases#nitrous-oxide https://www.epa.gov/ghgemissions/overview-greenhouse-gases#n...
- mikeash 10y agoThe "false" part is all the other oxides emitted by ships that don't contribute to climate change. Sulfur dioxide, for example, cools the planet.
- BurningFrog 10y agoThe added effect of one ship's N₂O emission has nothing to do with the preexisting level in the atmosphere.
- mikeash 10y agoSure it does. Adding 1000ppm CO2 to Earth's atmosphere would be catastrophic, while doing the same to Venus would be irrelevant, for example.
- quickben 10y agoMolecules don't block vs retain heat. They vibrate at a given frequency given the energy flow. https://en.m.wikipedia.org/wiki/Greenhouse_gas https://en.m.wikipedia.org/wiki/Greenhouse_gas
- mikeash 10y agoWhich, in the context of Earth's atmosphere, results in retention or rejection of heat.
- pas 10y agohttps://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch2s2-10-2.html https://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch2s2-1... SO2 has a cooling effect usually: https://www.reddit.com/r/askscience/comments/1o34mn/why_does_sulfur_dioxide_cause_a_cooling_effect_if/ccoebcb/ https://www.reddit.com/r/askscience/comments/1o34mn/why_does... but it can form dark aerosols that absorb heat (thus decreasing Earth's albedo)
- WhatIsDukkha 10y agohttps://www.epa.gov/so2-pollution/sulfur-dioxide-basics#effects https://www.epa.gov/so2-pollution/sulfur-dioxide-basics#effe... https://en.wikipedia.org/wiki/Sulfur_dioxide#As_an_air_pollutant https://en.wikipedia.org/wiki/Sulfur_dioxide#As_an_air_pollu... """Sulfur dioxide is a major air pollutant and has significant impacts upon human health.[34] In addition, the concentration of sulfur dioxide in the atmosphere can influence the habitat suitability for plant communities, as well as animal life.[35] Sulfur dioxide emissions are a precursor to acid rain and atmospheric particulates.""" So acid rain etc isn't really significant to you?
- mikeash 10y agoMy question was specifically about global warming. Thus the quote of the thing saying "global warming."
- WhatIsDukkha 10y agoBut that's quibbling over the poster's word choices and narrowing and distorting the understanding of people reading these posts. Why would you insist on that?
- mikeash 10y agoHow is it "quibbling" to point out that these emissions are not, in fact, particularly important to global warming? Are you saying that I should just treat all pollution equally regardless of its effects and ignore the details? I don't get it. This is not some meaningless detail. If 15 ships emit more greenhouse gases than all the cars in the world put together, that implies that everyone working towards sustainable cars is putting their effort in the wrong place and that climate change activists who don't talk about big ships are idiots at best, and scammers at worst. If, however, 15 ships emit more pollution of some other kind, that's quite different. Especially when the pollution in question tends to have relatively local consequences, and is mostly emitted in the middle of the ocean.
- Dylan16807 10y ago