OK, some context.
Joseph Fourier noted in about 1820 that by the albedo of the Earth, the planet should be much colder, and stated that something in the atmosphere was absorbing some of the outgoing heat and retaining it.
Tyndall, in 1859, did the first mapping of the absorption spectra of the the most common GHGs.
In 1896, Svante Arrhenious did the first quantative analysis, and noting the feedback of water vapor from increased CO2. His estimate of the effects of a doubling of CO2 was quite accurate, considering the science of the time.
Since that time there has been many studies on the differant affects of GHGs in the atmosphere. All have shown that it increases the heat retained in the oceans and atmosphere.
In fact, enough studies that there is not one Scientific Society, not one National Academy of Science, nor one major University anywhere in the world that denies the reality of AGW.
The largest organizetion of physicists in the world, the American Institute of Physics has this site with the history of the study of the greenhouse effect.
The Carbon Dioxide Greenhouse Effect