How much heat (in degrees) does the atmosphere of Mars absorbe before it hits the Marshian surface?

Answer 1

I dont know, but... The heat absorbed can be measured in energy units/surface area units. Not in degrees.
Part of the heat is absorbed from the coming radiation (light, etc) and part from the infrared emited from the planet.

Answer 2

I want to back up the first answer. Your question can't be answered in those terms. And it probably can't be answered in any units, like btu's that we commonly use. The likely data will be percentage of radiation received from the sun that is striking the planet surface. How much of that is converted to heat is another matter.
By the way, it is Martian