The problem with talking about recent trends i.e. the 20th century without putting them in the context of the warming coming out of the Little Ice Age e.g. <a href="http://www.scirp.org/journal/PaperInformation.aspx?paperID=3217">http://www.scirp.org/journal/PaperInformation.aspx?paperID=3217</a> is to attribute the results of a long term trend to short term variations such as 1970 -2000.