Does anyone have a good guesstimate of what percentage of Earth's surface area is covered by asphalt?

Question

or concrete, or some other human construction? How would one arrive at a decent estimate?

Answer 1

It's absolutely tiny.  Just take a look at Google Earth sometime and notice that you can't even see human construction unless you zoom way in.

Less than 1% no doubt.

Answer 2

I am a truck driver so I can tell you. 100% and I have been on all of it.

:) ric

Answer 3

I can't give you an exact answer but just recently I heard on the Discovery channel that the amount of land area occupied by humans was very small indeed considering the area of  the earth's surface. Therefore we can assume the area covered by asphalt or concrete is quite minuscule.

Answer 4

I have hear it is somewhere between 3 and 1%. With that said any amount of hard manmade surfaces mainly blacktop creates a micro-climate, making the area very hot.