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Old 07-03-2019, 03:20 PM   #6129 (permalink)
freebeard
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You quoted it back to me. https://www.princeton.edu/news/2018/...ly-cloud-cycle
Quote:
The researchers report in the journal Nature Communications that models tend to factor in too much of the sun’s daily heat, which results in warmer, drier conditions than might actually occur. The researchers found that inaccuracies in accounting for the diurnal, or daily, cloud cycle did not seem to invalidate climate projections, but they did increase the margin of error for a crucial tool scientists use to understand how climate change will affect us.

“It’s important to get the right result for the right reason,” said corresponding author Amilcare Porporato, a professor of civil and environmental engineering and the Princeton Environmental Institute. “These errors can trickle down into other changes, such as projecting fewer and weaker storms. We hope that our results are useful for improving how clouds are modeled, which would improve the calibration of climate models and make the results much more reliable.”

Porporato and first author Jun Yin, a postdoctoral research associate in civil and environmental engineering, found that not accurately capturing the daily cloud cycle has models showing the sun bombarding Earth with an extra one or two watts of energy per square meter. The increased carbon dioxide in the atmosphere since the start of the Industrial Age is estimated to produce an extra 3.7 watts of energy per square meter. “The error here is half of that, so in that sense it becomes substantial,” Porporato said.
....
Clouds change from hour to hour and from day to day. Climate models do a good job of capturing the average cloud coverage, Yin said, but they miss important peaks in actual cloud coverage. These peaks can have a dramatic effect on daily conditions, such as in the early afternoon during the hottest part of the day.

“Climate scientists have the clouds, but they miss the timing,” Porporato said. “There’s a strong sensitivity between the daily cloud cycle and temperature. It’s like a person putting on a blanket at night or using a parasol during the day. If you miss that, it makes a huge difference.”
https://en.wikipedia.org/wiki/Fresnel_equations

Quote:
Overview

When light strikes the interface between a medium with refractive index n1 and a second medium with refractive index n2, both reflection and refraction of the light may occur. The Fresnel equations describe the ratios of the reflected and transmitted waves' electric fields to the incident wave's electric field (the waves' magnetic fields can also be related using similar coefficients). Since these are complex ratios, they describe not only the relative amplitude, but phase shifts between the waves.

The equations assume the interface between the media is flat and that the media are homogeneous and isotropic.[1] The incident light is assumed to be a plane wave, which is sufficient to solve any problem since any incident light field can be decomposed into plane waves and polarizations.
Everything has Fresnel.
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