Scientists have been warning for decades that the oceans are warming, temperatures are rising and ice sheets are shrinking. But real action to mitigate and prepare for the effects of climate change—both locally and statewide—didn’t begin in earnest until the past decade.

And as the federal government entered into the Paris Climate Accord—then announced it would withdraw from it—California and local governments plowed forward in grappling with the realities of a planet in crisis.

The most recent California climate assessment in 2018 painted a dire picture for the nation’s most populous state: Death, damage to coastal properties, wildfires, droughts, mega-floods and costs in the tens of billions.

The state passed more than a dozen laws to deal with climate change between 2010 and 2019, including curbs to car and truck emissions, new building standards, clean energy requirements and cap-and-trade.

Among the new laws was the requirement that every municipality that receives a certain threshold of state funding compile a detailed assessment of how climate change will impact operations, and how it can pitch in to reduce pollutants.

Long Beach spent the last two years compiling data for its climate assessment report, which was presented in draft form in June 2019.

Over the next 10 years, the city is pledging to restore its dunes, incentivize reflective roofs and streets, and take sea level rise into account when approving new laws and negotiating new leases.

In the next 30 years, the city may begin relocating critical infrastructure and raise levees. And by the end of this century, the city will be extending seawalls, elevating storm surge barriers and finding ways to get homes and businesses out of flood-prone areas permanently.

That rough timeline is laid out in a draft of the city’s first Climate Action and Adaptation Plan, a document that still needs approval from the City Council and state officials.

Operations at the Port of Long Beach, a major economic hub, are also examined in a separate report that has already been approved by the state.

The biggest impacts in Long Beach are expected to come from sea level rise; a rapidly warming ocean is expected to rise 6 to 22 inches by 2050. Temperatures are also expected to rise as much as 8 degrees by the end of the century, and the city will see fresh water shortages and worsening air quality, according to the draft report.

Experts say extraordinary and painful decisions will have to be made in coming years, including whether certain areas are even inhabitable. There was a time when Long Beach’s peninsula strand was nearly 100 yards wide; now, it’s closer to 20 yards.

“There are ways to armor the coast, to forestall it, but we do know the impact will be significant,” Councilman Suzie Price, who represents parts of the Long Beach coast, told the Post last spring.