THE SENATE votes Wednesday on what sounds like an arcane regulatory question. In fact, Sen. Angus King (I-Maine) argued Tuesday, “This is the most important climate vote that the Senate has had, maybe ever.” The question indeed sounds technical: whether to use the Congressional Review Act to reverse a Trump administration rollback of Environmental Protection Agency rules on methane emissions in the oil and gas sector. But the vote will be an early indication of Congress’s seriousness about addressing global warming — and, by the same token, the depth of irrational opposition to action. A positive result would show the world that the United States has returned to sanity on one of the most pressing issues requiring global action. A negative vote — or passage by only a slim majority — would send a less encouraging signal.

The Obama administration developed rules to deal with methane, which is the primary component of natural gas. When burned, methane produces about half the amount of carbon dioxide as coal, so it can be a useful bridge to a non-carbon future. But if methane wafts into the air uncombusted, it is an extremely potent greenhouse agent on its own. It is shorter-lived than carbon dioxide, but it traps heat about 84 times more efficiently over 20 years. So methane leaks in drilling and transporting natural gas can negate the climate benefits of switching from coal to gas to generate electricity.

One of the most irrational moments in President Donald Trump’s anti-environmental frenzy came last August, when his administration moved to cut requirements that natural gas equipment installed after 2015 be inspected every six months and that any leaks be repaired within 30 days of detection. The Senate’s Wednesday vote would halt the Trump rollback using the Congressional Review Act, which provides lawmakers a streamlined process to reverse recent executive branch regulatory decisions.

A new study in the journal Environmental Research Letters found that existing technology could halve methane emissions by 2030, cutting the rate of global warming by as much as 30 percent. This would require effort on the part of oil and gas companies, ranchers and landfill operators, and government programs to plug abandoned wells.