Anyway he can change the constitution seems to be his mission.
Check this out:

President Barack Obama’s push to unilaterally commit the United States to reduce its carbon dioxide emissions in the coming years is about changing the constitutional system that similarly hampered former President Bill Clinton’s global warming goals, according to a law professor.

In a congressional hearing Thursday, George Mason University law professor Jeremy Rabkin told lawmakers that Obama’s argument that he unilaterally commit the U.S. to a United Nations agreement without Senate ratification was “a real change in our Constitution.”