Of the solar radiation entering the atmosphere, about % reaches the surface directly as direct radiation.

Of the solar radiation entering the atmosphere, about 22.5% reaches the surface directly as direct radiation and is being absorbed. Thirty five percent of it is reflected back to the space. While 10.5% and 14.5% are scattered to the earth from the blue sky and from clouds, respectively. Also, 17.5 percent was being absorbed by the atmosphere. Thus leaving only 22.5% to be given directly to the Earth's surface. Also, another factor of this low value would be the transparency of the atmosphere. The atmosphere of the Earth has only an effective transparent to radiation from the sun of about .34 to .7 micrometer. 

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