South Florida took the threat seriously before most everybody else, with four counties reaching a landmark compact in 2009 to work together to start addressing the risks of global warming.

But four years and one “super storm” named Sandy later, the risks to Miami-Dade, Broward, Palm Beach and Monroe counties — as well as much of coastal Florida — seem only bigger, scarier and no longer quite so far down the road.

An eye-opening example: Fort Lauderdale’s famous “strip,” where waves from Sandy, followed by routine high tides and heavy seas three weeks later, chewed away beach, seawall, sidewalk and roadbed, leaving a four-block-long swath of State Road A1A whittled from four lanes to two.

During a two-day regional climate change summit that ended Friday in Jupiter, political leaders and climate experts stressed two messages: One, South Florida faces a long, immensely costly war to protect its heavily developed coast and economy from the rising sea and increasingly destructive flooding from hurricanes like Sandy. Two, the “super storm” underlined why the region should quickly ramp up “adaptation” efforts and spending to reduce its exposure — from restoring beach dunes to building bigger sea walls to elevating roads and homes and maybe even moving them from the most vulnerable areas.

“Planning is nice, but now it’s all about implementation,’’ said Susanne Torriente, an assistant city manager in Fort Lauderdale who helped craft a wide-ranging climate-change action plan approved by Broward and Monroe counties in the past few months. County commissions in Miami-Dade and Palm Beach are expected to consider the plans by early next year.

Fort Lauderdale, Torriente said, is working with Broward County and state transportation experts on shoring up its heavily eroded strip. Repairs will easily run into the tens of millions of dollars and include elevating some of the iconic strip or building beach dunes, which some residents have long resisted because it spoils the view from AIA.

“Adaptation is not something we’re talking about in textbooks any more. It’s happening right in our backyard,” she said. “People like to see the water, but let’s be realistic.”

Though Sandy’s worst impacts were in the Northeast — where the storm killed more than 100 people, flooded New York City subways, swamped New Jersey coastal — it also caused extensive erosion along much of the South Florida coast.

While it remains uncertain what if any impact climate change had on Sandy, the devastating storm, which caused tens of billions of dollars in damage, gave both the public and political leaders across the country a glimpse of potential future scenarios. It also has injected new urgency in efforts in South Florida, many of the elected officials, planners, scientists, engineers and other experts at the annual regional summit agreed.

John Englander, an oceanographer who this year published a book called High Tide on Main Street, called Sandy a wake-up call for many coastal communities like Fort Lauderdale.

“People are starting to get increasing awareness to their vulnerability from storm surge,’’ he said. “They just can’t ignore the beach and walk away from billions of dollars worth of hotels.’’