Ah, yet more research that shows that the "Medieval Climate Optimum" period was indeed global, and not an "anomaly confined to Western Europe (or the Northern Hemisphere)" as the "global warmers" are so fond of claiming.
The one and only reason that the globalwarmingwhackos have steadfastly maintained that the Medieval Warming was not world wide is that the Science showing the warming there is Absolutely Irrefutable. When someone devises an equally good way of establishing that it was, in fact, worldwide, they'll figure out some other way to lie and obfuscate to their moronic target masses. I've yet to hear any of their vaunted "models" demonstrate any possible methodology for maintaining a warm Arctic for centuries without other major climactic ramifications, but their "faith" allows them to simply 'know' that earth is warmer now than ever before - because man's activities 'clearly' makes it that way.
It is amazing that those brilliant and super-advanced Islamists and Chinese and Africaners and Native Americans didn't maintain weather records during the 10th-17th Century so they could show how steady the global temperatures were for today's envirowhackos. A mere oversight on their parts, I suppose.
First of all, I think you're mixing up two terms. There was a "Holocene Climate Optimum" -- the period you're referring to is most commonly called the "Medieval Warm Period" or MWP.
Can you show provide references that indicate the MWP was truly global? The main problem is that there is so little data from the Southern Hemisphere.
By the way, Baffin Island is in the Northern Hemisphere.
For a bit of help, there is decent data showing that the cold period from 1400 - ~1850 was global, but most intense in Europe and the northern Atlantic region. Is that what you're thinking of?
You also might like to read this:
Climate in Medieval Time (PDF)
Excerpt of interest:
"There is evidence for widespread hydrological anomalies from 900 to 1300 A.D. Prolonged droughts affected many parts of the western United States (especially eastern California and the western Great Basin) (14). Other parts of the world also experienced persistent hydrological anomalies (15). For this reason, Stine (14) argues that a better term for this period is the Medieval Climatic Anomaly, removing the emphasis on temperature as its defining characteristic."
In the single figure in this reference, the Baffin Island record is #15, indicating that the warmest 30 year period in that record occurred about A.D. 1200. In the figure, records 4-6 are Southern Hemisphere, showing the warmest 30-year period between 1400-1500 -- which in Europe was the start of the Little Ice Age!