Anthropogenic global warming is a long term phenomenon that is caused by the release of Carbon, in the form of Carbon Dioxide, from fossil deposits, though burning of fuels such as oil, natural gas, and coal. There are other human causes as well, but some of those relate to the use of fossil fuels (such as the leakage of methane gas from oil extraction operations, or from delivery pipelines).
The evidence for warming comes from a variety of sources, but mainly from land based thermometer stations from about the mid 19th century and later, higher tech measurements such as satellites.
The following graph is provided by the National Climatic Data Center and comes with its own caption attached, providing the original source:
Just isn't explained well...a help me understand Plz.
The number is an estimate of how much warmer the planet is based on both measurements of the air at the surface of the land and the sea surface temperature.
One graph is for the whole planet, the other two are for the northern and southern hemisphere separately.
These charts show the definitive impact of industrialization since 1850. There is no doubt that man has sped up the global warming process, but how fast and was it going to happen anyway?