However, the average surface temperature of the planet seems to have increased far more slowly over this period than it did over the previous decades. (newscientist.com)
Some context: So far, we've raised the average temperature of the planet just under 0.8 degrees Celsius, and that has caused far more damage than most scientists expected. (rollingstone.com)
Another way of answering the question might be «the very long term equilibrium temperature of a planet with X amount of CO2 and H2O in this orbit is X». (realclimate.org)