Sens. Chris Murphy (D-Conn.) and Susan Collins (R-Maine) unveiled the upper chamber's first bipartisan climate bill of the year on Wednesday, ahead of the pope's address to Congress.

The Super Pollutants Act of 2015 comes a day before Pope Francis is expected to discuss climate change in his historic speech to a joint session.

The bill is intended to encourage federal agencies to work with businesses and nonprofits to adopt new technologies to limit the presence of so-called "super pollutants" in the atmosphere.

The legislation targets non-carbon dioxide greenhouse contaminants, which include refrigerants from refrigerators, soot from diesel engines and methane leaked by landfills.
"Establishing national standards to reduce short-lived climate pollutants is a critical step forward in the fight against climate change. SLCPs are doing some of the worst damage to the atmosphere but are a problem too few people are talking about," said Murphy in a statement.

He said the bill would also "drive economic growth here in the United States by making smarter use of the tools already at our disposal.”

The bill also comes a day after Senate Democrats unveiled a legislative proposal that would reduce greenhouse emissions, provide incentives for developing clean energy and overhaul a tax code that they believe favors fossil fuels.

Advocates for addressing climate change are using the pontiff's visit to Washington, which began on Tuesday, to draw attention to their cause. Francis has been a strong advocate for tackling climate change, and brought it up in his statements at the White House on Wednesday.

“I find it encouraging that you are proposing an initiative for reducing air pollution. Accepting the urgency, it seems clear to me also that climate change is a problem which can no longer be left to a future generation,” he said, offering support for President Obama's climate rules.