Wednesday, June 5, 2024

About that 1.5 C Existential-Threat Benchmark...

The number that is internationally agreed upon is 1.5 degrees Celsius. To prevent worsening and potentially irreversible effects of climate change, the world’s average temperature should not exceed that of preindustrial times by more than 1.5 degrees Celsius (2.7 degrees Fahrenheit).  Source


Topaz Solar Farm, California

If asphalt pavement raises ambient temperatures because it is dark and converts much of the incident solar radiation into heat, then what happens when you cover the landscape with solar panels?

Red trace reports temperature in PV farm as deviation from ambient. Blue trace is urban parking lot. Scale is degrees C. Horizontal axis is by hour-of-day
At least one study reported data that showed a 2-to-4 degree C increase in the air temperatures in large photovoltaic farms above ambient temperatures during the months of July and August. In fact, the temperatures were uniformly higher in the PV farms than they measured over urban parking lots.

One study at one location doesn't make this "Good Science" but it does make me wonder why there are not more studies. If +1.5 degrees C is an "existential threat" then what is +4 degrees C. Answer: A business opportunity.


  1. Looks like the law of unintended consequences strikes again!

  2. I will consider thinking that "der climate!" is changing, once the folks who tell me that "der climate!" is changing, begin to behave, themselves, as if "der climate!" is changing.

  3. Can you say 'selective science'? I knew you could... sigh

  4. That's what Science, politics, education and medicine are all about now. --ken

  5. The meme that you get the science you paid for comes to mind.

    The Watermelon Greenies (Green on the outside, commie red inside) don't care about mere facts. Logic is lost on them.

    The rank and file I've noticed when I try to talk with them remind me of the crowd in the Monty Python "Life of Brian" when told by Brian "You are all individuals" they chant back "We are all individuals".... Brian says "You have free will" they chant back "we have free will"...

    1. the only way we can catch that rise in temp is by lighting off the '' cow farts'' in the pastures right Ken

    2. Yup. And the ones when you're sitting there having a beer. ---ken

  6. It's worse than asphalt because both sides of the solar array radiate heat. More surface area for heating the surrounding air.

    Of course, less mass to store heat, but still.

  7. Don't forget that all that heat is energy lost by the solar array.
    The very best solar panels are about 22% efficient. Most are less than 17% efficient. The rest of the solar incidence to them is lost as heat - a safety tip: don't touch a solar panel in full sun; they can burn you!


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