Read here. As Copenhagen climate alarmists always attempt to focus the debate on a short period of warming starting in the mid-1970's, it's always important to remind them that a major "global warming" has been happening since the end of the Little Ice Age, and it has absolutely no relationship to human CO2. It is natural warming that periodically asserts itself despite human wishes and actions.
Case in point, in the Lake Baikal area of Russia, evidence was found that actual major warming started as early as...
"1750 AD, with a shift from taxa that bloom during autumn overturn to assemblages that exhibit net growth in spring (after ice break-up). The data here mirror instrumental climate records from Fennoscandia for example, which also show over the last 250 years positive temperature trends and increasing early summer Siberian temperature reconstructions. Warming in the Lake Baikal region commenced before rapid increases in greenhouse gases, and at least initially, is therefore a response to other forcing factors such as insolation changes during this period of the most recent millennial cycle.”