Global warming is claimed to be a 20th Century problem caused by man. In fact, what really happened is that early in the 20th Century, the U.S. and most of the industrialized world started practicing Daylight Saving Time.
DST is used to give us more daylight hours to work in. Well! Of course the Earth is going to get warmer when there is an extra hour of daylight to heat it up during DST!
All we need to do to stop global warming is to get rid of DST!