[thedoc (OP)]

Peter McGowan asked the Naked Scientists:
   If oil is pumped from the ground which has insulation properties is it not possible that this condition could be aiding global warming. ?
How many cubic miles of oil are extracted from the earth each year ?
What do you think?

[chris]

Relative to the volume of the Earth, the volume of oil extracted is literally a drop in the ocean. And relative to the heat-conserving effects of the atmospheric CO2 it produces when burned, any thermal insulating effect or heat-transfer effect of ground oil is vanishingly small.

Thus, the bigger problem is the co2 in the atmosphere and its long dwell time there (hundreds of years), meaning that what we put into the air today is a problem for many generations to come, not just us...

[Bored chemist]

Oil is liquid. In the ground it can carry heat by convection (albeit slowly and badly). If you take the oil out, you are left with porous rock which may well be a rather better insulator than the oil filled rock was.

But, as has been pointed out, the volume of oil is tiny compared to that of the earth, so any effect would be invisible.

[chris]

If you take the oil out, you are left with porous rock which may well be a rather better insulator than the oil filled rock was.

Good point about convection, but I am doubtful of the point about porous rock. Oil is usually recovered by replacing the volume, under pressure, with a denser material, such as "mud" and water. As such, these too could convect could they not?