16 Comments

Yeah, the Mesozoic had a wide variation in Temperature, coupled with a stable CO2 concentration.

That jumped right out at me.

Wuzzup widdat?

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Those silly dinosaurs changed the albedo by sunbathing.

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This might provide a clue:

Simulating 195 million years of global climate in the Mesozoic

https://phys.org/news/2021-08-simulating-million-years-global-climate.html

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No particular clue, but interesting.

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Variation in solar output might be one issue for some, and the increasing surface area of oceans (absorbing more solar energy than land), another.

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I was thinking the same. The Tethis Ocean in the equatorial zone must have had a strong effect on the albedo

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Each of the points would have some specific meaning in terms of temperature and CO2 "balance". There are so many variables. In that period CO2 did not change much, but temperature did. Why and Why? It seems complex.

Are the measurements reliable?

Questions...

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It IS complex

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Too many variables for comfort indeed but the increasing surface of the oceans caused entire island populations to relocate and continues to do so. Part of that increase is due to melting of icecaps. This lowers the water temperature (cold blob near Greenland), that in turn lowers humidity. Lower humidity---> fewer clouds. As the specific heat of air is much lower than that of water, the air warms faster, lowering rel. humidity, resulting in a drier and warmer climate.

I put theory to practice, able to grow borojo fruits where 20 years ago, that was impossible. Nowadays the nighttime temperature often is 5-7C above what it used to be even 10 years ago. "Canary in the coalmine" location maybe but it forbodes rather well what to expect.

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It's hard to correlate a human perception with geology...

;-(

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Maybe the answers can be found in the rate of sedimentary deposition stalagmite formation in relation to the increased rainfall patterns from increased atmospheric water circulation. Lower clouds have a much larger albedo effect than higher clouds and one would think increased rain bearing lower cloud mass in a warmer world would allow increase concentrations of co2 without increased warming due to the faster heat release cycle of rain forming clouds. There are some interesting articles on temperature and cloud / rain formation and the release of energy from the earths biosphere. Many thanks

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