The most important contribution of the recent National Climate Assessment to our conversation on climate change may very well be its focus on risk assessment, allowing us to shift the conversation away from a singular focus on not “knowing” the future toward a more useful focus on the probable risks associated with unmitigated climate change.

Those unwilling to accept the strong scientific consensus on climate change have long insisted that we simply need to attain a greater degree of knowledge before taking action. In response, scientists have done more research, written more reports, and presented more evidence. …

The recently released Fourth National Climate Assessment emphasizes the need to take immediate action on climate change to prevent economic instability and “growing losses to American infrastructure” while preserving “the health and well-being of the American people.”

The report makes it clear that the benefits of acting now far outweigh any reasons to delay. Ignoring the risks of climate change in the face of widespread scientific consensus on the evidence would be like a gambler ignoring the odds stacked against them in a high-stakes game of chance.

Now more than ever, we need political leaders to act like responsible data-driven risk managers rather than gamblers. If we use evidence-based probabilities to manage risks in other areas of life, why wouldn’t we do the same when it comes to climate change? …

Let’s say you go to your doctor and she tells you that you have cancer. She says it is metastasizing but you can treat it with an aggressive course of action.

Naturally, you want a second opinion, and so you go to a cancer specialist. They tell you the same thing. Perhaps a third opinion wouldn’t hurt?

So, you seek out another expert oncologist who comes back with the same prognosis and recommends you begin treatment right away. But, what if these doctors were wrong?

You insist you need more evidence before taking action. So, you seek a fourth opinion…and a fifth, and a sixth, and a seventh, and so on. In fact, you go out and enlist a panel of 100 expert oncologists to take you through more batteries of tests and issue a series of written reports to compile all the data and present their findings. …

It’s often said that you don’t realize what you have until you lose it. For over a week now, those of us living in the Bay Area have been forced to grapple with losing that one thing we all rely upon to live healthy and productive lives: air.

As you know from news reports, a devastating fire — ironically named the Camp Fire — wiped out the town of Paradise at the foot of the Sierras in Northern California, claiming over 70 lives with over a thousand people still unaccounted for as of this morning.

Smoke from the fire has combined with a high-pressure system sitting off the coast and cooler surface temperatures as we head toward winter. This has effectively created a lid that has trapped smoke from the fire over much of Northern California. Bad air quality in the Bay Area has resulted in numerous school and business closures this week since it is unhealthy to venture outside, let alone exercise outside. …

The US is in the middle of an unprecedented oil boom leading to rising fortunes in the global energy economy. According to a recent article in the New York Times, “This year, the United States is expected to surpass Saudi Arabia and to rival Russia as the world’s leader [in oil production], with record output of over 10 million barrels a day.” This prosperity arises from technological advances that make new shale fields accessible at lower investment costs. Places like North Dakota and New Mexico are becoming “world class petroleum hubs” and the building of new pipelines allows energy companies to take their product to “ports where oil can be pumped onto tankers headed for China, India and other markets.” …

Mike Pence was right. So was Paul Ryan, Reince Priebus, Mitch McConnell, Chris Christie, Marco Rubio, and even Dick Cheney. Sure, a few have now changed their tune as part of a Faustian pact. But all of these Republican leaders at one point rightly denounced Trump’s proposed “Muslim ban.” During the campaign, Gen. James Mattis said that implementing such a policy would indicate that “we have lost faith in reason.” Indeed, there is no compelling reason — even from an “America first” perspective — to implement the arbitrary restrictions put in place with President Trump’s executive order last Friday.

Whether you call it a “Muslim ban,” “extreme vetting” or Executive Order 13769, Trump’s order to block entry of valid visa holders from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen for 90 days — plus an indefinite ban on Syrian refugees — has little to do with vetting, extreme or otherwise. We had and still have an extremely rigorous vetting process in place for refugees and those applying for visas from these seven countries. Trump’s executive order does nothing to change or improve those vetting processes. …