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Re:MIT-designed project achieves major advance toward fusion... by veltas on Thursday September 09, 2021 @03:25AM (#28467198)
How do we know that global temp rise isn't just due to energy usage? I mean "does that calculation fit at all?", not "carbon dioxide is fake".
Re:MIT-designed project achieves major advance toward fusion... by thow-58d4e8b on Thursday September 09, 2021 @03:51AM (#28467337)
Not even close.

Global energy use is around 170,000 TWh/year (1). This includes electricity generation, as well as fuel for transport, burning wood for heat, etc.

Heat flow from mantle is 403,000 TWh/year (2)

Solar irradiance is ~1200W/m2, which adds up to massive 5B TWh/year.

Extra radiative forcing from greenhouse gases in IPCC scenarios is ~3W/m2, or around 12.5M TWh/year.

The radiative forcing is two orders of magnitude larger than our energy use.

(1) https://en.wikipedia.org/wiki/World_energy_supply_and_consum...

(2) https://www.nature.com/articles/ngeo.2007.44

Re:MIT-designed project achieves major advance toward fusion... by sokoloff on Thursday September 09, 2021 @10:44PM (#28477201)
I believe total annual solar irradiance is closer to 1.5BTWh/yr.

The 1200-ish W/m/m figure is hitting a flat plate circle, not hitting the whole spherical surface.

Taking 173,000TW of continuous solar energy* times 24h/d times 365.25 d/yr yields a little over 1.5B TWhr/yr

* https://news.mit.edu/2011/energy-scale-part3-1026

Re:MIT-designed project achieves major advance toward fusion... by veltas on Thursday September 09, 2021 @03:55AM (#28467360)
Thanks, this is the calculation I was looking for.
Re:MIT-designed project achieves major advance toward fusion... by jabl on Thursday September 09, 2021 @03:35AM (#28467253)
Because we know that so far humanity's energy use is so small that the heating effect via increased blackbody radiation equilibrium temperature is utterly dwarfed by what mainstream climate focuses on, like GHG gasses.
Re:MIT-designed project achieves major advance toward fusion... by chriswarbo on Thursday September 09, 2021 @03:50AM (#28467332)
It's the difference between a hand-warmer and a coat. The hand-warmer adds extra heat to the system (like the heat from burning fossil fuels). A coat doesn't add any extra heat, it just traps some of the heat that would otherwise be lost (like greenhouse gasses).

Hand-warmers can keep part of the body warm for a few hours. Coats can keep the whole body warm for years.