The current controversy over the cause of increasing global temperatures since the middle of the 20th century comes from the IPCC First Assessment Report issued in 1990. Current, reliable evidence shows the Earth has just come through a warm period. It is now in the early stages of cooling that might be similar to the Dalton Minimum and last for three or four decades. Average temperatures can drop by up to 1.5 degrees C and increase the rate of crop failures that have already started. It won't be easy to maintain the benefits of the recent warm phase of the Sun during the upcoming solar minimum.
