The Obama administration is rushing to beef up its legal defense in preparation for a major court fight next month that could decide the fate of the centerpiece of the president's climate agenda.

The Justice Department and the Environmental Protection Agency have been presenting a federal appeals court with arguments to strengthen their case for keeping the Clean Power Plan in place based on the global threat of climate change.

The power plan directs states to cut their greenhouse gas emissions one-third by 2030 by targeting existing power plants. The emissions are blamed by scientists for causing the Earth's temperature to rise, causing severe drought and flooding. The Supreme Court stayed the plan in February until all legal challenges are heard. Those legal challenges begin Sept. 27 with oral arguments in the D.C. Circuit Court of Appeals.

Justice Department lawyers are flagging a recent victory for the Department of Energy in the 7th Circuit Court of Appeals over its pricey appliance efficiency standards to strengthen their case against the dozens of states and industry groups challenging the power plan.

The 7th Circuit court also vindicated the White House's cost metric, called the Social Cost of Carbon. The administration's cost metric has gained the ire of the Republican leadership for being a moving target that only seeks to raise the cost of energy for the consumer. But the court ruled that the metric was "neither arbitrary nor capricious."

The EPA also is touting the court's rejection of the energy industry's arguments that the Energy Department appliance standards were arbitrary because the agency had considered the rules' global benefits vs. national costs. Opponents of the Clean Power Plan also are using that argument in their court case.

"The 7th Circuit found reasonable Energy's explanation that 'climate change 'involves a global externality,'' and that these global effects 'are an appropriate consideration when looking at a national policy.' It further noted that petitioners had not identified any 'global costs' that Energy should have considered," the EPA document says.

The 7th Circuit court concluded, therefore, that the Energy Department "acted reasonably when it compared global benefits to national costs."

EPA's global argument appears to be an attempt to secure the Clean Power Plan as a central part of the U.S. plan to meet its obligations under December's Paris climate change deal. President Obama said earlier this month that he will be working to ensure the deal moves forward by the end of the year.

Although the deal was agreed to, the Paris accord still requires at least 50 percent of the countries that signed onto it to formally ratify it at the United Nations. The EPA is now arguing that the global benefits of the Clean Power Plan justify it moving ahead under the 7th Circuit ruling and undercuts the arguments by the nearly 30 states and dozens of industry groups that are opposing it.

House Natural Resources Committee Chairman Rep. Rob Bishop, R-Utah, said the 7th Circuit's decision raises huge concerns by justifying the Obama administration's "incalculable" arithmetic for gauging the effects of climate change on everything from new shopping malls to energy projects, roads and bridges.

"This ruling sets a dangerous precedent," Bishop said. "We intend to conduct further oversight and will work to rein in this audacious abuse of executive authority."

The EPA sent a second letter Aug. 17 refuting arguments made by opponents of the Clean Power Plan in an Aug. 8 letter to the court, citing a case between the sugar industry and the agency. Those fighting the EPA said the July ruling in the Sugar Corp. case showed that the agency has limited discretion to interpret the Clean Air Act as it sees fit in limiting emissions from a facility.

But the EPA argues just the opposite. It said the July court ruling in Sugar Corp. "largely upheld Clean Air Act emission standards covering over 200,000 boilers and waste combustors, and correctly applied the deferential Chevron standard to EPA statutory interpretations, and the deferential arbitrary-and-capricious standard to agency judgments concerning energy requirements, costs and achievability."

The Chevron standard refers to a previous court ruling that many agencies use to justify their actions. It gives the EPA wide latitude in implementing its rules under the Clean Air Act.