“The summer water temperatures, reconstructed from the makeup of tiny organisms buried in sediments in the Fram strait”
This can only construct postulated temperatures, not actual temperatures as they were and the difference between the accuracy of those postulates and the actual temperatures can be as great as the 0.8 degree difference claimed to have occurred in the last 2,000 years.
Yeah I was wondering where they got a precise measurement of ocean currents flowing to the arctic during the Roman Empire and medieval periods.