“We found that northern hemisphere temperature and Greenland temperature changed synchronously at periods of ~20 years and 40–100 years. This quasi-periodic multi-decadal temperature fluctuation persisted throughout the last millennium, and is likely to continue into the future.”
Takuro Kobashi et. al. http://www.springerlink.com/content/n567324n1n3321h3/
I wish I could compile all these old articles..
…and add up the temperature changes they reported
I’ll bet the Arctic would have warmed up at least 50 degrees…
1937
“Particulars are given regarding the big rise of winter temperatures in Greenland and its more oceanic climate during the last fifteen years.”
http://onlinelibrary.wiley.com/doi/10.1002/qj.49706327108/abstract
“The warmest year in the extended Greenland temperature record is 1941, while the 1930s and 1940s are the warmest decades.”
B. M. Vinther et. al.
http://www.cru.uea.ac.uk/cru/data/greenland/vintheretal2006.pdf
Natural cycle?