All gasses are greenhouse gasses. If we compensate for the effect of gravity, a planet with a hydrogen atmosphere is warmer than a planet with no atmosphere. A planet like Earth with an atmosphere of hydrogen and oxygen is warmer than it would be if we had only the former.
Carbon dioxide has an Earth warming effect only slightly greater than nitrogen and oxygen. Current levels of carbon dioxide in our atmosphere contribute much less than one degree to our climate. Any measurement made by anyone should show similar results.
Ignore the theoretical mathematics and conduct a test in real time. Don't base the global warming relationship on what we believe happened over the past thousand years.
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