3 to 4 degrees centigrade warmer, in fact. Far greater than recent warming.

The new paper, Kulman et al. 2018 relies on paleoclimatology, which as we’ve learned from Mann, can be taken with a grain of salt.

Because trees may only grow within narrowly-defined temperature ranges and elevations above sea level, perhaps the most reliable means of assessing the air temperatures of past climates is to collect ancient treeline evidence.

In a new paper, Kullman (2018) found tree remnants at mountain sites 600 to 700 meters north of where the modern treeline ends, strongly implying Early Holocene air temperatures in northern Sweden were 3-4°C warmer than recent decades.