Hi Larry

To keep its cool the Earth has to draw down the nitrogen. Eventually a Runaway Greenhouse kicks in because the pressure drops to just 0.08 bar and the temperature rises to 27 C. It'll be a strange world after that - a hot version of Lowell's Mars, with the hydrogen leaking away into space and the surface rusting with all the oxygen liberated.

But perhaps not. The subduction of water from the oceans isn't well understood and different estimates of the relevant processes mean the oceans will drop by several hundred metres or even several kilometres over the next ~2 billion years. That'll counteract the greenhouse and the hydrogen loss.