‘It’s kind of like shark CSI.’ Experts assess how frozen shark washed up on Cape Cod beach.

© Amie Medeiros A porbeagle shark washed up on a beach in Dennis.

During New England’s artic blast Saturday, photographer Amie Medeiros ventured onto a Cape Cod beach in sub-zero temperatures to embark “on a little photo adventure.”

While capturing scenes of icy waters and wispy clouds at Cold Storage Beach in Dennis, Medeiros stumbled upon something peculiar: a fin sticking out of the sand in the distance. Intrigued, she trekked down the shoreline to investigate, she recalled Tuesday in a message to the Globe. There, she found a dead, frozen shark.

Despite her rapidly numbing fingers, Medeiros snapped photos of the shark — lying on its side, sharp teeth exposed — and posted them to her Instagram photography account, @capeimagesbyamie. The eerie images have since gotten thousands of likes.

“It’s definitely wild, how I’ve gotten my frozen friend his 15 minutes of fame,” the 41-year-old Yarmouth Port resident wrote. “[My friends] have been happy my photos are getting recognition because they love how they capture Cape Cod life.”

John Chisholm, an adjunct scientist at the New England Aquarium, went to Cold Storage Beach Monday morning to inspect the dead shark, which he identified as a porbeagle, a species related to great whites.

The porbeagle did not die because of the cold snap, Chisholm said, and was likely dead for several days before Medeiros came across it. As it happens, porbeagles are uniquely adapted to withstand frigid water temperatures, unlike other shark species such as threshers and sand tigers, he said.

“[Porbeagles] have evolved to develop a countercurrent heat exchange system in their veins and arteries,” Chisholm said. “So they can raise their body temperature .... They can tolerate the cold.”

The shark washed up during the artic blast, so its body froze when it was on the beach.

“If we didn’t have that sub-zero weather, this shark wouldn’t have frozen, it just would have been a dead stranded shark,” he said.

Chisholm said he went to Cape Cod to investigate the porbeagle’s condition and try to determine how it died.

“It’s kind of like shark CSI,” he quipped.

By the time Chisholm arrived, however, the shark’s eyes were already pecked out — likely by gulls — and several fins were missing. The body had begun to decompose and it looked as if dogs or coyotes nibbled at it, too, Chisholm said.

Without an intact corpse, Chisholm said it’s impossible to collect enough data at the New England Aquarium’s lab to determine the cause of death or compare the shark to others that have recently washed up. The aquarium plans to leave the shark’s body on the shore and “let nature take its course.”

People have shared the photos on social media and marveled over just how frigid New England was last weekend.

“How cold was it yesterday? Cold enough to wash a frozen shark onto a Cape Cod beach!” one person tweeted Monday. “This was the scene yesterday at appropriately named Cold Storage Beach in Dennis, MA.”

Others said they are scared to swim in Cape Cod waters given so many shark sightings.

“I used to swim in those waters as a kid,” one commenter said. “I’ll barely stick a toe in the water nowadays.”

Sharks washups aren’t particularly common in the New England region, Chisholm said, so it’s important that passersby report sightings to wildlife officials. Institutions like the New England Aquarium analyze washups to try to identify patterns, diagnose problems, and find solutions to protect wildlife.

If you witness an animal washed ashore, you can report it to Chisholm through social media, which is @MA_Sharks on Instagram, Twitter, and Facebook.