One need only to use your computer and Google William Happer to find what a distinguished career he has had and to appreciate his expertise in gas (CO2) spectroscopy. Then one might do a Google search for IPCC fraud, which on Jan. 8 produced about 607,000 results in 0.35 seconds, or a search for global-temperature fraud that produced about 11,600,000 results in 0.47 seconds. The articles clearly cast doubt on a consensus countering Happer’s viewpoints. In regard to CO2 as a greenhouse gas, one might ask how and why does it act. Yes, it reacts with infrared radiation (wavelengths commonly listed as ranging from 0 to 1000uM) in three narrow fingerprint absorption points: 2.9, 4.3, and 15uM. The great bulk of infrared passes by unaffected.
NASA has pointed out that CO2 can protect the Earth from harmful bursts of solar radiation by intercepting it in the upper atmosphere. Again, water in all of its forms (vapor, liquid, and ice) has CO2 absorption bands that overlap that of CO2. The concentration of water vapor is many times that of CO2 in the atmosphere, and in the laboratory, one cannot demonstrate a significant greenhouse effect for CO2 in the presence of water vapor. Hopefully, Trump does pay attention to Happer.