Two weeks ago New Scientist reported the results of a kind of mini systematic review of global temperatures since 1850. In it Michael Le Page argues that the best baseline period - to give the temperature before global warming started - is 1850 to 1899. For convenience some temperature series use 1880-1899 as their baseline but this is misleading because temperatures in the 1880s were depressed by the eruption of Krakatoa.
When the five available temperature series are adjusted to use 1850-1899 as baseline it's clear that four of the five will show more than one degree of warming before the Paris IPCC conference this Autumn.
That's halfway to the the two degree level generally thought to imply a strong probability of catastrophic climate change.
Le Page continues with the prediction that unless we take "drastic action" the Earth will reach that two degree point by around 2050.