That's a good question that is too less asked. Regarding the cubic expansion coefficient of 0.00021/ºC and the earth surface is covered with approx. 220 million km2 of water it has with a depth of 3.5 km a total expanded volume 1.617×10⁵ km3.
When you divide this volume with approximately 250 million km2 (the sea surface will expand on land), the water level will rise with about 0.65 meters.
And when this doesn't happen the average earth temperature obviously didn't rise, because you can't argue about obvious facts.
Perhaps you can recalculate my calculations, because I did it somewhat quick.
That was damn good question!