The fact is, there has been global warming, but the contribution of human-generated carbon dioxide
is necessarily so minuscule as to be nearly undetectable. Here's why:

Carbon dioxide, considered the main vector for human-caused global warming, is some 0.039% of the
atmosphere[1]- a trace gas. Water vapor varies from 0% to 4%[2], and should easily average 1% or
more[3] near the Earth’s surface, where the greenhouse effect would be most important, and is about
three times more effective[4] a greenhouse gas than carbon dioxide. So water vapor is at least
25 times more prevalent and three times more effective; that makes it at least 75 times more important
to the greenhouse effect than carbon dioxide[5]. The TOTAL contribution of carbon dioxide to the
greenhouse effect is therefore 0.013 or less.
The total human contribution to atmospheric carbon dioxide since the start of the industrial revolution
has been estimated at about 25%[6]. So humans’ carbon dioxide greenhouse effect is a quarter of 0.013,
works out to about 0.00325. Total warming of the Earth by the greenhouse effect is widely accepted as
about 33 degrees Centigrade, raising average temperature to 15 degrees Centigrade, or 59 degrees Fahrenheit.
So the contribution of anthropogenic carbon dioxide is less than 0.2 degrees Fahrenheit, or under 0.1 degree
Centigrade. Global warming over the last century is thought by many to be 0.6 to 0.8 degrees Centigrade.