Some longtime residents of the mid-Atlantic remember the great freeze of 1977, when deep and prolonged cold covered most of the Chesapeake Bay with a sheet of ice.

That freeze disrupted shipping channels, locked in workboats and cut off islands like Smith and Tangier. The ice was thick enough to support the weight of cars, and people flocked onto the expanse to skate in the shadow of the Bay Bridge.

As Maryland enters another prolonged cold snap — temperatures aren’t expected to climb above freezing until next week, while lows dip into the single digits — could pirouettes under the Bay Bridge be in the cards again?

Don’t bank on it.

While pockets of the bay commonly freeze, scientists said ice as extensive as the famous 1977 event would require a much more prolonged stretch of intense cold.

As of Tuesday, about 11% of the bay was covered by ice, according to the U.S. National Ice Center, a division of the National Oceanic and Atmospheric Administration. Most of that ice was concentrated in the bay’s northernmost reaches near Havre de Grace, where salt concentrations are lowest.

In late January a year ago, ice covered nearly half of the bay, according to the federal agency.

The bay could see a similar picture this week, predicted Hali Kilbourne, a climate scientist with the University of Maryland Center for Environmental Science.

But even then it likely won’t be thick enough to skate on.

In an email, Kilbourne, who is based at the Chesapeake Biological Laboratory on Solomons Island, said that she would be surprised to see substantial ice coverage south of the Bay Bridge near Annapolis after just a week of subfreezing temperatures. The roughly 85% ice coverage of 1977 occurred during a freeze that lasted nearly two months, she said.

Victoria Coles, who also researches climate impacts on the bay at the UMCES Horn Point Laboratory, said widespread ice coverage won’t happen quickly.

“If you want to get all geeky and physics about it, it just takes a ton of energy to cool and heat water,” she explained.

The recipe for widespread ice coverage as in 1977, Coles said, likely would require a colder-than-usual fall, to push water temperatures down in the bay, followed by an intense winter cold snap. Ideal conditions for ice also include low winds, she said, since wind tends to churn salt water into the mix.

On Tuesday near Crisfield in the Lower Bay, thin “pancake ice” floated in the central channels but turned two to three inches thick on the fringes of Smith Island, according to Captain Shawn Ridgley, who pilots an icebreaker boat for the Maryland Department of Natural Resources.

Ridgley’s boat, the Eddie Somers, is one of three icebreakers deployed by the state during freezes like this one, though he said the oldest in the fleet is currently out for maintenance.

The main concern for the boat’s crew is clearing a channel for comings and goings from Smith Island, as well as for local watermen. But thanks to an emergency declaration in Virginia, Ridgley said, the Maryland icebreaker is also on tap to help Tangier Island farther south.

Climate change has made extensive freezes on the bay less common in recent decades, a phenomenon noted in a brief 2018 paper by James L. Foster, an emeritus scientist at the NASA Goddard Space Flight Center.

The paper, “History of Ice on the Chesapeake Bay,” documents significant freezes on the bay dating back to the year 1600. For the most part, freezes have been confined to the fresher waters of the Upper Bay, but Foster wrote that at least two winters in each century were so cold that almost the whole bay became locked in ice.

“From time to time, however, cold Arctic air pours across the upper Mid-West and into the eastern U.S., nearly uninterrupted for weeks at a time,” wrote Foster. “These are the winters that ice cover in the Chesapeake Bay becomes remarkable.”