this post was submitted on 03 Mar 2024
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Climate - truthful information about climate, related activism and politics.

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Discussion of climate, how it is changing, activism around that, the politics, and the energy systems change we need in order to stabilize things.

As a starting point, the burning of fossil fuels, and to a lesser extent deforestation and release of methane are responsible for the warming in recent decades: Graph of temperature as observed with significant warming, and simulated without added greenhouse gases and other anthropogentic changes, which shows no significant warming

How much each change to the atmosphere has warmed the world: IPCC AR6 Figure 2 - Thee bar charts: first chart: how much each gas has warmed the world.  About 1C of total warming.  Second chart:  about 1.5C of total warming from well-mixed greenhouse gases, offset by 0.4C of cooling from aerosols and negligible influence from changes to solar output, volcanoes, and internal variability.  Third chart: about 1.25C of warming from CO2, 0.5C from methane, and a bunch more in small quantities from other gases.  About 0.5C of cooling with large error bars from SO2.

Recommended actions to cut greenhouse gas emissions in the near future:

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[–] [email protected] 4 points 8 months ago

The solution has always been better cities and better mass transit. EVs are a distraction.

[–] [email protected] 20 points 8 months ago* (last edited 8 months ago) (1 children)

This would be much more efficient if it had other transportation as well.

Like non-electric cars, trains, subways, etc.

It's not too hard to get their efficiency as well.

NEXT DAY EDIT: Should've looked, there's actually a handy chart showing the energy efficiencies of a whole bunch of vehicles and modes of transport just straight up on Wikipedia. This article. Comparing the km/MJ column, we can see:

Walking 4.55

Velomobile with enclosed recumbent: 12.35 (there wasnt a figure for just regular biking)

Solar car: 14.93

Tesla Model 3: 1.76

General Motors EV1: 1.21

All combustion engines are below 1, but here's a few:

VW Passat: 0.33 Cadillac CTS-V: 0.17 Renault Clio: 0.42

There's a whole bunch of other stats though so I suggest checking the table

END EDIT

[–] [email protected] 2 points 8 months ago (2 children)

Also biking and walking are not necessarily even viable for certain commutes such as any over about 4 miles/ whatever that is in kilometers say 8, and anytime I need to carry heavy luggage / groceries. Or anytime anybody with mobility issues needs to travel.

It's all very well insane if we wanted to buy an e-bike and get rid of their car but that's not really practical.

[–] [email protected] 1 points 8 months ago

The break-even distance in urban areas, where it takes the same amount of time to bike, is typically more like 7 miles. That's about half of commutes. Not a 100% replacement for everybody, but big enough to make a meaningful difference.

[–] [email protected] 1 points 8 months ago (1 children)

<7km is too far to bike?

Oh man. Well, I agree on the other things you said, but... 6.4 km isn't that much. It's a fair bit, yeah, but not that much. With an e-bike, it's not really even a thing. I chose to use the healthcare in the next city over (I live on the border of two cities) and I have about ~7km whenever I go there. 10-15 min with an ebike. With a regular one it'd be a chore, but it wouldn't take much longer, 20-25 minutes maybe with a loose pace.

But yeah biking definitely can't replace everything. I mean, cargo bikes exist, but still.

With mobility issues, we now have a lot of mobility "scooters" that go about 25km/h per the EU regulations. Like a super buffed up wheelchair. with a sort of chassis. Small enough to fit in the back of a taxi-van that has a disabled lift, but still quick enough to use in a similar way as a bike.

Still tho. I want my cheap rental ecars.

[–] [email protected] 1 points 8 months ago (1 children)

Bikes don't have to replace everything to make a big difference. Something like "use them as the default choice for shorter distances" makes a big difference.

[–] [email protected] 1 points 8 months ago

Oh definitely.

I would like to one day see one of those horrible American cities that you can't even traverse on foot / bike, but I don't want to step a foot in the US, with the whole fucked up corruption, military-industrial complex, and the whole budding protofascism.

[–] [email protected] -3 points 8 months ago (2 children)

How does biking or walking consume energy ?

[–] [email protected] 6 points 8 months ago (1 children)

You burn calories when you exercise

My 30km round trip bike to work burns about ~800 calories, or 1.33 big-mac equivalents, which has a carbon footprint of about 4.2kg CO2

That same round trip would burn 2L gasoline in my car, which has a carbon footprint of about 4.6kg CO2

[–] [email protected] 1 points 8 months ago* (last edited 8 months ago) (1 children)

Edit: I see where you are getting your numbers now after looking around. I will leave my comment here for sake of others seeing it and the discussion.

How are you getting 4.2 kg of CO2 for 800 cal???

The average estimate is 0.35 per 1000 cal for the more eco friendly

https://ourworldindata.org/grapher/ghg-kcal-poore

https://www.globe.gov/explore-science/scientists-blog/archived-posts/sciblog/index.html_p=183.html

If you are eating stupid amounts of meat every meal, sure you might average that high.

And more than that, the food is just CO2, arguably not as bad of a GHG. the petrol/gasoline also has the really bad stuff people don't bring up as much, such as the nitrogen-oxides and sulfurs.

[–] [email protected] 1 points 8 months ago* (last edited 8 months ago)

numbers are just cursory googles so they may be off, e.g. "carbon footprint of a burger" (~3.2kg CO2 per) followed by "calories in a big mac" (590)

The majority of the calories in a burger come from the bun and condiments, so it's pretty far from a "stupid" amount of meat - As sad as it is, the average american eats 12.2oz of meat a day, and a big mac only has 3.2oz

Food production (particularly beef and rice) are among the worlds largest sources for methane (a worse GHG) - also usually fossil fuels burned by production/transportation is generally factored into these estimates

Regardless, the point i was poorly making is that this infographic sucks because it makes a false equivalency between "energy efficiency" and "good for the environment". As I noted - biking is substantially more energy efficient than driving an ICE (~21x; 800 vs 16680), but after adjusting for the carbon footprint of food, that 21x becomes somewhere in the range of ~1-9x depending on diet. I suspect this graphic doesn't list ICEs because they weight half as much and likely come in at a higher efficiency (despite being better for the environment) - which of course goes against the narrative it's trying to present

[–] [email protected] 3 points 8 months ago* (last edited 8 months ago) (1 children)

Food tends to have significant energy inputs in the form of methane gas used in the production of nitrogen fertilizer, diesel tractors, transportation, and cooking

[–] [email protected] 1 points 8 months ago
[–] [email protected] 19 points 8 months ago (1 children)

While I like this chart, it's useless without the tradeoff. It also needs to map speed to time spent. What is being given up for improved efficiency? The inflection point is how you move people from point A to point B.

[–] [email protected] 12 points 8 months ago

The biggie is urban planning to ensure that people don't need to travel huge distances on a routine basis. That means that people give up very little.

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