A recent US Supreme Court decision to halt implementation of Obama's Clean Power Plan put the brakes on climate protection - nationally, and with international implications. But Justice Scalia's death changes everything.
Immediately after the Supreme Court halted implementation of Obama's Clean Power Plan, an environmental lawyer friend of mine compared the decision to Bush v. Gore.
"One paragraph, no rationale, politicized garbage," were his exact words.
In Bush v. Gore - a decision from the United States presidential election in 2000 - the US Supreme Court essentially allowed G.W. Bush to steal the presidency from Al Gore - despite Gore having ultimately won both the popular vote, and very possibly the Electoral College as well.
In both Supreme Court decisions, a key vote was cast by Antonin Scalia.
Scalia, in his record as a Supreme Court justice, has been aptly described as "reactionary" and "arch-conservative." He had staunchly opposed the right to abortion, and gay and lesbian rights - as well as environmental protection.
And now he's gone.
So what does that mean for US climate policy - and, by extension, global climate protection?
Essential climate support from US
Obama's Clean Power Plan in August 2015 established a landmark national framework for reducing greenhouse gas emissions from the generation of electricity. In that framework, over the next 15 years production of power from the dirtiest coal plants would be gradually reduced, as renewable energy is ramped up.
It's a solid plan, and the core policy tool for implementing US pledges to protect the climate - among pledges from nearly 200 countries to reduce greenhouse gas emissions to prevent dangerous global warming.
These pledges were brought to the table in Paris last November for the COP21 climate conference. If added up, they exceed the maximum 2-degree warming limit from the Paris Agreement - so there's currently still a hefty emissions gap.
The Clean Power Plan represented a first - albeit insufficient - step in the direction of reducing greenhouse gas emissions from one of the world's largest producers.
Such "ambition" - coming from a country that until then had opposed limitations on greenhouse gas emissions - was a crucial element in pulling other countries onboard toward the historic Paris Agreement to limit global warming that emerged from COP21.
The thing is, the Clean Power Plan was passed not as a law, but rather as a regulation. In the US policy framework, regulations are developed and implemented by federal agencies under direct control of the ruling administration - while new laws are put into place through congressional voting.
US conservatives had seen Obama's rule-making in this case as a way to get around congressional law-making.
Seen from this perspective, the Supreme Court's decision to not only challenge the Clean Power Plan but also prevent it from being implemented until Supreme Court is able to decide the case, was indeed very political.
But in terms of climate protection, the Supreme Court panel of justices is looking very different without Scalia.
Several possible scenarios
In one scenario, Obama would recommend a center or left-center candidate as a new Supreme Court justice.
If approved, this justice would very likely allow the agencies in charge of implementing regulations - in the case of the Clean Power Plan, the Environmental Protection Agency - to carry out their mandates as determined by the ruling administration.
In another scenario, Republicans could follow through on their threat to delay approval of Obama's recommendation for Supreme Court justice through a filibuster.
The Supreme Court, one justice down, might then be deadlocked in a four-to-four vote on the Clean Power Plan. That would put the decision back to the lower court - which is likely to also allow the regulatory agency to implement the plan.
In a third scenario, a new president would appoint a new justice. Since the race is still up in the air at this point, one could only speculate as to how this might play out.
A Democratic president would, like Obama, likely appoint a center or left-center justice, equaling the result of the first scenario.
If a Republican other than Donald Trump is elected, that president would likely appoint a center-right justice. And since far-right Scalia was basically an enemy to the climate, any other person might make a more moderate decision on the Clean Power Plan.
Shudder to think of what a justice chosen by Trump might be like. In terms of climate protection, that would be the worst-case scenario.
Overall, it looks like as long as Trump doesn't win, the climate would.