Science Never Just "Says"....

Breakpoint ^ | 9-15-22 | John Stonestreet and Shane Morris

[thepoodlebites]

Excellent plot of the energy budget for Earth. Had to check the units for the black body curve, Watts per Meter² per Steradian per Micrometer. Units for irradiance is just W/m^2 but radiance includes an angular component (Steradian), like looking at the sky through a metal pipe.

It’s interesting to note the almost complete absorption of incoming solar radiation in the UV region under the black body curve (red line). The intensity of the solar radiation peaks in the middle of the visible region (~500 nanometers, green light), exactly where water is most transparent to light (an inherent property of water). Scientists should note these properties (dwarf yellow star, ~5500 degrees K surface temperature, terrestrial planet at a distance from the host star of one AU) in the search for habitable planets.

Water vapor absorption is significant for wavelengths greater than one micron, CO2, not so much. Climate sensitivity to a doubling of CO2 is most likely no more than one degree C but with clouds providing a net negative feedback, catastrophic warming is highly unlikely.

If climate was that sensitive to CO2 we would have suffered a runaway greenhouse effect (similar to Venus) a long time ago. The fact that we are here bears witness to the long-term stability of our climate. The key to our survival is the oceans, the raining-out of water from the atmosphere provided a natural thermostat.