Searchers combing the Java Sea for signs of the missing AirAsia passenger jet have the advantage of working in much shallower waters than those found in the open ocean but also face challenges that include monsoons, murkiness and trash.

Flight 8501 disappeared Sunday morning with 162 people on board while flying from western Indonesia to Singapore. Searchers found Tuesday several pieces of debris floating off Borneo island in the Java Sea but are still trying to determine if they're connected to the missing plane.

Erik van Sebille, an oceanographer at the University of New South Wales in Sydney, said the Java Sea is 100 times shallower than the remote stretch of Indian Ocean where searchers are still looking for another missing plane, Malaysia Airlines Flight 370.

"It makes the search much simpler," he said.

Mostly enclosed by islands from the Indonesia archipelago, the Java Sea has average depths of about 40 to 50 meters (131 to 164 feet). Van Sebille said it's shallow enough that if conditions were perfect, searchers could probably spot any large pieces of debris on the ocean floor using only their eyesight.

"In the last ice age, it was actually land. It was above sea level with forest," he said. "It's a much different environment than the open ocean."

But because the monsoon season is underway, he said, there's likely to be lots of rain that will wash sediment into rivers that feed into the sea and make it murky. And he said the abundance of fishing in the region will make it harder for spotter planes to distinguish trash from any plane debris.

"It's a pretty filthy ocean and there's a lot of garbage floating out there," he said. "Everything from small water bottles to big, abandoned fishing nets."

He said the currents in shallow seas don't typically have the same strength as those in the open ocean, meaning debris shouldn't move as much, although he said winds can quickly create choppy waves which can make the search more difficult.

David Gallo, the director of special projects at the Woods Hole Oceanographic Institution in Woods Hole, Massachusetts, said the challenge of locating the wreckage or black boxes remains huge.

Gallo said the area where searchers are looking for the AirAsia jet might appear much narrower and more contained than the area for Flight 370 but is still enormous: "bigger than West Virginia and South Carolina combined," he said. That is about the same size as Indonesia's Java province.

But unlike in the search for Flight 370, he said, ships searching the Java Sea can be smaller and reach the area more quickly because they will be much closer to a port.

However, he said, searchers may need to get a better grasp on the last known position of the plane before they are ready to try to detect any underwater locator signals, or pings, which the plane's black boxes are designed to emit.

"There is nothing easy about this," Gallo said.

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Perry reported from Wellington, New Zealand