A massive algae bloom is sitting off the coast of New Jersey and isn’t expected to move off any time soon.

The bloom, which is not considered harmful, was first detected by satellites in mid-July but has grown almost 50 percent larger since then, according to scientists at Rutgers University’s Institute of Marine and Coastal Sciences.

Algae blooms in the ocean are not uncommon in late summer, but it’s the size of this bloom, which extends some 70 miles from Barnegat in Ocean County to the tip of Cape May County, that has scientists calling this unusual.

"The size and the concentration is on the upward end of what we usually see,’’ said Josh Kohut, associate professor at the institute. "This is a big bloom.’’

The bloom, about 30 miles offshore, is being fueled by upwelling in the ocean — where the south/southwesterly winds blow off the warmer surface of the ocean to expose the cooler water, Kohut said. Now exposed to sunlight, phytoplankton in the water that are feeding on nutrients have perfect conditions to grow, he said.

Kohut said the winds are forecasted to continue blowing from the south at least until Monday, which will keep the bloom away from beachgoers on the shore. But that means that upwelling will continue, allowing the bloom to grow in size and thickness, he said.

The state Department of Environmental Protection is monitoring it, said Larry Hajna, a department spokesman. He said the agency plans to deploy a boat today (SATURDAY) to take samples of the bloom and will launch a plane to assess the size of the bloom.

"Most algae species are harmless to people," Hajna said. "As a precaution, we’re going to go out and confirm what species is out there."

“Hopefully the bloom dissipates so that fisheries and beaches are protected,’’ said Jeff Tittel, director of the New Jersey Chapter of the Sierra Club. "Most of the algae is harmless, but could lead to fish kills and beach closings as the algae robs oxygen out of the water.’’

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