It is an assumption - planet emitting as a blackbody

There is also another thing in the Greenhouse warming theory which is not proper referenced - it is the assumption planet emitting as a blackbody. Where does it come from? Who said that first? The entire greenhouse warming theory is a not valid theory. It doesn't withstand the scientific method requirements.

Here is an illustrative example on how wrongly the Earth's IR emission is estimated. 

"Summary

This figure shows the absorption bands in the Earth's atmosphere (middle panel) and the effect that this has on both solar radiation and upgoing thermal radiation (top panel). Individual absorption spectrum for major greenhouse gases plus Rayleigh scattering are shown in the lower panel.

Both the Earth and the Sun emit electromagnetic radiation (e.g. light) that closely follows a blackbody spectrum, and which can be predicted based solely on their respective temperatures. For the Sun, these emissions peak in the visible region and correspond to a temperature of ~5500 K. Emissions from the Earth vary following variations in temperature across different locations and altitudes, but always peak in the infrared. The position and number of absorption bands are determined by the chemical properties of the gases present. In the present atmosphere, water vapor is the most significant of these greenhouse gases, followed by carbon dioxide and various other minor greenhouse gases. In addition, Rayleigh scattering, the physical process that makes the sky blue, also disperses some incoming sunlight. Collectively these processes capture and redistribute 25-30% of the energy in direct sunlight passing through the atmosphere. By contrast, the greenhouse gases capture 70-85% of the energy in upgoing thermal radiation emitted from the Earth surface."

"By contrast, the greenhouse gases capture 70-85% of the energy in upgoing thermal radiation emitted from the Earth surface."

Our comment:

Planet has not a uniform surface temperature.

Nevertheless, in the Greenhouse warming IR emission theory planet is considered as a perfect blackbody uniform temperature emission surface - so it is concluded planet surface IR emission frequency bands should fit to the Stefan-Boltzmann emission curve. 

The frequencies not detected (measured) in the planet IR emission pattern are considered being absorbed by the atmosphere...

It is a common knowledge though, no planet has a uniform surface temperature.

How it is possible, how can anyone expect from a planet surface to emit in a perfect blackbody curve pattern? Since planet has not even the most basic requirement for the perfect blackbody curve - planet has not a uniform surface temperature!

" Both the Earth and the Sun emit electromagnetic radiation (e.g. light) that closely follows a blackbody spectrum, and which can be predicted based solely on their respective temperatures."

"...which can be predicted based solely on their respective temperatures."

It is an assumption, and it is a very mistaken assumption! Because a planet doesn't have a uniform surface temperature! Planet surface doesn't emit as a disk, because planet is a sphere...

Earth doesn't emit IR radiative energy at the uniform Te = 288 K. Each infinitesimal spot emits at its own respected temperature...

They measure earth's IR emission, but those measured data cannot be compared with the Te = 288 K S-B emission curve bands...

So they are not justified to conclude    "...the greenhouse gases capture 70-85% of the energy in upgoing thermal radiation emitted from the Earth surface."

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