Taxing polluters under Initiative 1631 is a desperate move. Should voters support it? Yes, but ...

A landmark climate-change report released last week was so jolting, and so blunt in laying out an earlier-than-expected doomsday calendar, that one might think it was timed to promote Washington Initiative 1631.

It wasn’t. And yet the findings by this international panel of scientists struck with an immediacy that should cause voters to seriously consider imposing the nation’s first carbon fee on polluters — and hope others follow fast.

The report concluded global temperature increases would bring widespread famines, floods, fires, population displacements and more by 2040. If society doesn’t take “unprecedented” steps within a few years, we should prepare for the worst, warned these scientists convened by the United Nations.

The report certainly heightened this Editorial Board’s sense of urgency. It helped tip us into the “yes” column for I-1631, despite the measure’s flaws.

Perhaps our endorsement is best described as “Yes, but…” The carbon-fee program, if not monitored carefully, could turn into a messy grab bag of pet projects.

A revenue-neutral fee on carbon dioxide emissions that returns dividends to taxpayers, similar to state Initiative 732 that was defeated in 2016, is arguably a superior approach.

But we believe Americans can’t let a perfect policy be the enemy of the good any longer. Inaction, epitomized by President Trump’s withdrawal from the Paris climate agreement, must stop.

Some voters (few, we hope) reject I-1631 out of hand because they reject the scientific consensus on global warming. Others opposing the measure might be fatalists whose views hardened after last week’s dire U.N. report. Eat, drink, be merry and burn fossil fuels — for tomorrow the planet dies.

For most Washington voters, however, I-1631 might boil down to this question: Will we continue to value our profligate consumer lifestyle above the priceless ecological legacy we leave our children and grandchildren?

In the South Sound, we already see the effects of climate change in melting Mount Rainier glaciers, high-intensity storms and declining shellfish beds.

Under I-1631, oil companies and the state’s other big greenhouse-gas polluters would pay $15 per metric ton of carbon content starting in 2020, then increase by $2 each year. The exceptions, including a coal plant that will shut down by 2025, are largely defensible.

These ratepayers will likely do what they always do: Pass it on to consumers. The fee could add as much as 14 cents to a gallon of gas, for starters, plus higher prices for utilities, food and other expenses.

For households living on the margins, that’s not insignificant. But the initiative designates funds for low-income assistance and to retrain workers in fossil-fuel industries that will inevitably shed jobs.

Most of the revenue would go toward clean-energy development. Microsoft co-founder Bill Gates, who declared his support for I-1631 last week, predicted Washington would become a “hub” for innovative research and businesses. That’s a credible argument from Washington’s most famous entrepreneur.

But we’re not over the moon with excitement for 1-1631.

It quite possibly doesn’t goes far enough to help Washington meet its emission targets, let alone prevent environmental calamity. Some experts say a fee of at least $30 per metric ton is needed to stabilize carbon output and start reversing the tide.

The initiative also has a lax design for spending the estimate $2.3 billion in annual tax revenue.

An unelected, 15-member oversight board would administer the fund. In addition to clean-energy development, money would go toward reducing flood and wildfire risks, relocating communities affected by sea-level rise and funding projects on tribal land.

The link to climate change get fuzzier in the 5 percent of funds set aside for “healthy communities investments.” The I-1631 campaign told us projects could include rural broadband internet. Say what?

That’s why our support comes with a caveat: Legislators must take a strong hand with the oversight board and retain the power of the purse. They’ll also have to fix the inevitable problems that surface once any new tax or fee by an autonomous agency goes into effect. (Case in point: Sound Transit.)

But while lawmakers can help manage and improve a carbon-pricing system, our state can’t keep waiting for them to create one. Gov. Jay Inslee has long pushed for a fee or a cap on carbon but hasn’t convinced the Legislature to buy in.

So voters are left with Initiative 1631, imperfect as it is. A “yes” vote will show the country we’re leaders in combating a climate collapse in the next two decades. A “yes” vote will show our grandkids we won’t gamble with their futures.