Read here. Climate alarmist scientists can't catch a break as 2009 tree-ring study again proves Medieval Warming summer temperatures exceeded modern summer temperatures, despite a lower atmospheric level of CO2. Also, the Little Ice Age was confirmed as a prominent climate feature in the mountainous area.
Note the downturn during the late 20th century. Similar to the infamous "hide the decline" downturn discovered with Climategate revelations? (click on image to enlarge)