The first amendment was offered by Ranking member Rep. Henry Waxman (D-CA):
"Congress accepts the scientific finding of the Environmental Protection Agency that 'warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level.'"
It was defeated 20-31, with all Republican members voting to deny EPA's scientific findings.
The second amendment was offered by Rep. Diana DeGette (D-CO) and read:
“’the scientific evidence is compelling’ that elevated concentrations of greenhouse gases resulting from anthropogenic emissions ‘are the root cause of recently observed climate change.’”
This amendment was defeated 21-30, again with all Republicans voting against the amendment.
The third amendment was offered by Rep. Jay Inslee (D-WA) and it said that human-caused climate change is a threat to public health and welfare. Again, the vote was 21-31 with all Republicans voting against the scientific consensus.
It should be made clear that the US National Academies of Sciences last year noted that:
A strong, credible body of scientific evidence shows that climate change is occurring, is caused largely by human activities, and poses significant risks for a broad range of human and natural systems….
In addition, recent studies have documented that very nearly all active climate researchers concur that the planet is warming and greenhouse gases are the predominant factor. Also, the most recent IPCC report, the National Academies of all of the major countries of the world, and pretty much all of the major scientific organizations on the planet concur that the climate is changing and that human activity is the major cause. The US National Academies called it "settled fact." So when Republicans unanimously vote against basic scientific principles they are in fact voting to deny the science.
Read more about the vote in articles in The Hill and Politico.