Global methane emissions from human activities must be reduced 40% to 45% by 2030 to limit the average temperature rise to a critical 1.5 degrees C, said a new United Nations report.

Cutting methane pollution nearly in half would prevent close to 0.3 degree C in warming, found the researchers who synthesized the latest research and produced the May 6 assessment for the United Nation's Environment Programme, or UNEP.

The oil and natural gas sector, one of the top three largest, human-caused contributors to rapidly rising methane concentrations in the atmosphere, would be required to slash its share by 60% over the next decade, the report found. Such reductions would be most needed in North America, the Middle East, and Russia, all large oil and gas producers.

In all, drilling, transportation, and processing of oil and gas account for 35% of all human-made methane emitted worldwide. The agriculture sector is responsible for 40% and organic waste for 20%.

"Driving down emissions of these ... gases is a critical, fast mitigation strategy that delivers immediate climate benefits," Rick Duke, a senior advisor to Special Presidential Envoy on Climate John Kerry, told reporters during a briefing on the report. "In the near-term, to keep 1.5 centigrade degrees within reach and prevent dangerous warming, deep methane reductions are as important as carbon dioxide reductions."

Duke said U.S. President Joe Biden's administration will take "ambitious action" to address methane as part of its new commitment under the Paris Agreement on climate change to reduce the total U.S. greenhouse gas output by 50% to 52% by 2030. That includes proposing new standards to control leaks from oil and gas facilities as well as developing new programs through the U.S. Department of Agriculture to control methane from farmland and livestock, the single-largest global source of methane globally, Duke said.

Citing the need to curb methane pollution, the U.S. Senate on April 28 used the Congressional Review Act to repeal a Trump administration decision that rolled back pollution controls on new and modified industrial sources in the oil and gas sector. Passed during Trump's final months in office, the rollback also eliminated a similar rule for existing facilities.

Duke said that in addition to curbing pollution at home, the U.S. will "continue to prioritize methane in all our climate diplomacy," working through groups like the Global Methane Initiative as well as by engaging bilaterally with other nations.

The American Petroleum Institute, a large industry trade group, said it welcomes policies to rein in emissions from the oil and gas sector.

"API is focused on working with the Biden administration in support of the direct regulation of methane for new and existing sources and building on the significant progress our industry has made in reducing methane emissions through technological advancements," Stephen Comstock, the group's vice president of corporate policy, said in a May 6 statement.

UNEP's "Global Methane Assessment" is also notable because it estimates, for the first time, the costs and benefits associated with a worldwide push to rein in the potent greenhouse gas.

For each metric ton of methane that would be reduced, the monetized benefit would be about $300, according to the Duke University researchers who crunched the numbers. And by reining in methane, levels of ground-level ozone would also drop. This would result in 255,000 fewer people dying annually from severe respiratory ailments and other health problems annually, a benefit the researchers said comes to about $450 billion annually.

As a result, the researchers said nearly 85% of the investments needed to reduce methane releases bring benefits that will ultimately outweigh the cost. This is also because abatement can be relatively inexpensive and even "cost negative" and result in financial gains, they noted.

The greatest potential for that would be in the oil and gas sector where captured natural gas adds more revenue, the UNEP report said.

"So it's really a win-win-win here," said Inger Andersen, UNEP executive director and author of the report. "It's a matter of the governments setting the guardrails and on the global agreements setting the overarching targets scientists ask for."