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Climate change: US emissions in 2020 in biggest fall since WWII

bbc.com

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Re: Climate change: US emissions in 2020 in biggest fall since WWII

#81

Post by evgen »

throwawayboise wrote: post #76
tryptophan wrote: post #56

Earlier quoted context omitted.

IMO ammonia makes more sense than hydrogen. It doesn't cause metals to become brittle. Its relatively stable. It doesn't require as low temperature or as high pressure to liquidize. It also stores ~50% more hydrogen per volume, as each ammonia has 3 hydrogen, unlike elemental hydrogen with just 2.

It's also highly toxic and a leak in the wrong place could kill thousands of people.

But we have handled ammonia on an industrial scale for more than a century and are really good at it. Any safety concerns about ammonia are ridiculous when compared with some of the other substances we handle and live around on a daily basis.

Re: Climate change: US emissions in 2020 in biggest fall since WWII

#82

Post by throwawayboise »

savanaly wrote: post #10

Is it possible that Sars-cov-2 epidemic will eventually save more lives than it cost, through the long term and short term effects of decreased pollution and climate change? If that's true, we have to entertain the theory that the virus was purposefully initiated by a time-traveler charged with averting climate catastrophe through the only means possible.

I would think if you've got the technology to time-travel, fixing the atmosphere in your present day would be trivial. Same reason the plot lines of The Terminator films never really made sense (though they were very entertaining movies).

Re: Climate change: US emissions in 2020 in biggest fall since WWII

#83

Post by mywittyname »

xur17 wrote: post #35
citilife wrote: post #25

Earlier quoted context omitted.

> Is it possible that Sars-cov-2 epidemic will eventually save more lives than it cost, through the long term and short term effects of decreased pollution and climate change? Climate change wont directly lead to death, we'll have to adapt, but there are models showing more food produced from climate change. Simply put, we don't know what potentially will happen. We highly suspect there are 150 thousand increase in d…

> Given 25 million have tested positive, by the prior estimates, that means a likely 250 million Americans have already gotten covid [4] Considering there are 328 million Americans, that would mean 76% of Americans have had the disease, which I believe would be sufficient for herd immunity. Given what case counts look like, I find that extremely unlikely.

>that would mean 76% of Americans have had the disease, which I believe would be sufficient for herd immunity.

My understanding is that it is possible to get covid-19 multiple times. But lack of widespread testing is making it difficult to measure how prevalent this is.

There are also two known strains of covid.

There are a lot of unknowns at this point. We could be dealing with cyclical covid outbreaks for the next decade, the vaccine rollout this summer might eliminate it for good, or we could land somewhere between the two.

Re: Climate change: US emissions in 2020 in biggest fall since WWII

#84

Post by Jtsummers »

davio wrote: post #67
throwaway0a5e wrote: post #24

Earlier quoted context omitted.

For a lot of people it was their only alone time.

I only listen to podcasts while driving, so my "learning" time has been drastically reduced

I converted my commute time to walking time and yardwork time last spring through fall (too cold for walking now, and yardwork is now 10 minutes of shoveling snow every couple of weeks). I think I listened to more thanks to the lack of a commute. I didn't feel bad about leaving the house at 4:30pm (end of workday for me) and finding my way back home at 5:30pm or 6pm, especially since I knocked out a lot of household chores/tasks during the workday in quick 1-5 minute bursts so I was more helpful around the house than when I was in the office.

Re: Climate change: US emissions in 2020 in biggest fall since WWII

#85

Post by andromeduck »

nostromo wrote: post #69
jedberg wrote: post #2

And personal savings are way up. But it's unlikely either of these trends will hold after 2021.

Not true... US carbon emissions have been going down for over a decade, even as population increases. https://www.macrotrends.net/countries/USA/united-states/carb...

Mostly due to displaced manufacturing though no?

Re: Climate change: US emissions in 2020 in biggest fall since WWII

#86

Post by chrisseaton »

badRNG wrote: post #3
jedberg wrote: post #2

And personal savings are way up. But it's unlikely either of these trends will hold after 2021.

Source? Anecdotally most folks I know have had to burn through their savings after living off of unemployment or going through underemployment this past year.

If you haven't lost your job then your savings are both up (markets) and not being spent (as there's nothing to spend them on.)

Re: Climate change: US emissions in 2020 in biggest fall since WWII

#87

Post by letsgoyeti »

ggreer wrote: post #65
gecko wrote: post #34

Earlier quoted context omitted.

Hydrogen as part is totally reasonable. It gives us hydrocarbon density without us needing to add to the CO2 in the atmosphere. The important thing to remember when discussing it is that it's an energy storage medium, not an energy generation medium. Most of the time I get irritated is when people treat hydrogen as the latter. But if our culture is just too damn wedded to cars for now, and battery tech just isn't the…

Hydrogen vehicles will never become popular. There are several reasons for this: - To be carbon-neutral, the hydrogen must come from splitting water.[1] Currently hydrogen comes from steam reforming of methane (which releases lots of carbon).[2] - Hydrogen is a very pernicious molecule. It will slowly leak through metal and weaken it.[3] - Hydrogen vehicles must be refueled at special fueling stations. Electric vehic…

I think most hydrogen proponents are pushing for it to replace hydrocarbons for shipping, planes, and seasonal energy storage, not cars.

There's not a lot of other great options today if we want to decarbonize those sectors because of the energy density required.

Re: Climate change: US emissions in 2020 in biggest fall since WWII

#88

Post by philipkglass »

r00fus wrote: post #77
throwawayboise wrote: post #76

Earlier quoted context omitted.

It's also highly toxic and a leak in the wrong place could kill thousands of people.

And hydrogen substrate isn't similar?

Hydrogen is not toxic by inhalation, but it's a much worse explosion/fire risk.

Hydrogen is flammable when mixed with air between 4% and 75%, and it takes a minimum energy of 0.016 millijoules to ignite. Ammonia is flammable between 15% and 28% and takes 680 millijoules to ignite. It takes much more energy to ignite ammonia and there's a much narrower range of mixtures with air where it can support combustion.

https://en.wikipedia.org/wiki/Flammability_limit#Examples

Re: Climate change: US emissions in 2020 in biggest fall since WWII

#89

Post by breakfastduck »

just_steve_h wrote: post #70

The biggest takeaway here for me is that we collectively achieved something previously considered impossible: by making different behavioral choices, as a species, we achieved the largest cut in CO2 emissions in 75 years. It's tragic that only the threat of a deadly disease could compel such a change, but perhaps we may find other levers to help us achieve such widespread beneficial changes in the future?

All it does it prove how fruitless the prevention of climate change is.

A total shutdown of the entire world economy on an unprecedented scale still doesn't track enough to prevent climate change.

If that isn't a clear indicator of how severe the situation is then I don't know what else is.

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