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] -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