Today Trump makes it official: he's reopening tough Obama-era vehicle-mileage and tailpipe carbon-emissions rules for model years 2022-2025 for more review and, very possibly, a rollback.

Why it matters: the rules for cars and light trucks are a pillar of Obama's climate and energy policy.

• EPA estimated that the standards for those years would cut oil consumption by 1.2 billion barrels and save consumers an average of $1,650.
• But big automakers, citing federal estimates that complying with standards would cost billions of dollars, argued the rules will hurt jobs and are way out of step with consumer preferences.

What's next: A senior White House official told reporters Tuesday evening that Trump's Detroit-area visit with auto executives and workers will include the announcement that he's withdrawing a January 12 EPA decision that locked in standards. Obama's EPA concluded just before he left office that the standards could be met at "reasonable cost" through a "number of different technological pathways."

The White House was careful to say that it's not prejudging the outcome of what's expected to be a year-long analysis, claiming instead that it wants to do a more careful version of a process critics said Obama's EPA rushed through without enough analysis.

But all that said: the White House dropped more hints that it's very sympathetic to the industry view that EPA's January findings were riddled with problems. The official vowed to arrive at rules that are "technologically feasible, economically feasible." Environmentalists are bracing for an effort to water down the standards that currently set a fleetwide average of 54.5 miles per gallon in 2025.

The White House confirmed that EPA isn't, for now, seeking to end the Clean Air Act waiver that gives California—and by extension over a dozen other states—leeway to maintain the tough Obama-era rules. But California is bracing for a fight and the state has tapped Obama's former attorney general Eric Holder to help its defense.

Who, what, where: The Detroit News has a good rundown of the auto executives and others taking part in Trump's events in Michigan today.

On Tuesday I asked a bunch of Senate Republicans about Trump's push to cut EPA's budget by around $2 billion—maybe even more, as Axios exclusively reported Tuesday.

The response? Senators didn't bash the plan, and there is GOP support for scaling the agency back, but outright endorsement of that level of cuts didn't materialize. The closest thing I heard to support was from Environment and Public Works Chairman John Barrasso, whose committee oversees EPA but doesn't write its spending legislation. He said he didn't see the cuts as "excessive," but wanted more details.

Several other Senators, including some Appropriations committee members, basically demurred on talking numbers.

• "We will see what the president has to lay down on Thursday," Lisa Murkowski, head of the Appropriations subcommittee that crafts EPA's budget, told reporters in the Capitol. "We will deal with it in appropriations."
• John Cornyn, the majority whip, was equally meh. "The president proposes and Congress disposes, so we will see what comes out of it," he said when asked if there's appetite for the level of cuts that Trump is pitching.

Why it matters:

The cautious responses just days from the budget rollout underscore what other sources call the lack of votes and appetite for those kinds of cuts, which Democrats would never support. Some House Republicans have also signaled that Trump won't get all the EPA cuts he wants.

• "I am optimistic that we will have bipartisan support for a much more realistic number," Sen. Ben Cardin, a liberal Maryland Democrat on EPW, said.

A clearer picture is emerging of Trump's looming executive order that targets Obama's global warming policies. Bloomberg reports on two of the pieces expected to go:

• White House guidance to agencies telling them to incorporate climate change into project reviews under the National Environmental Policy Act.
• The government's use of a metric known as the "social cost of carbon" that measures economic impact of climate change which the Obama administration used to justify some regulations.

Why it matters:

For a while we've known that the centerpiece is a plan to start the long process of unwinding EPA's carbon emissions rules for power plants, and that it will also overturn the Interior Department's freeze on new coal leases on federal lands in Western states. But the inclusion of the other provisions underscores how the White House is waging a very broad assault on Obama's effort to weave climate change into the fabric of federal decisionmaking across the government.

Reuters has the latest on the controversial Dakota Access pipeline project that was delayed under Obama but given a green light under Trump. Oil could start traveling next week through the line that connects the Bakken oil fields in North Dakota to a terminal in Illinois.

A federal judge denied a Native American tribe's request for an emergency injunction.

The former veep, out with a new edition of his 2007 book "The Assault on Reason," sizes up Trump EPA chief Scott Pruitt and his views on climate change. Via NPR's transcript:

• "[I]n some ways, it's not at all new for wealthy and powerful interests to try to hide the ball and ignore independent analyses of relevant facts. But we see a prime example of this now with the new head of the EPA (laughter) brazenly declaring that CO2 has nothing to do with the climate crisis."

CityLab looks at plans that could enable even larger-scale offshore wind power in Europe than we're seeing already. The key? An artificial island that a Danish-Dutch-German industry consortium envisions.

Here's a blurb from their story:

• "Still at blueprint stage, the island would act as a power hub at the center of a vast new wind farm, at a scale that hasn't been seen anywhere else thus far. Surrounded by a turbine array with a generating capacity of between 70,000 and 100,000 megawatts, the island would channel this energy through direct live cable connections to the countries surrounding the sea."