慢速美语 - 科学新闻 Huge Iceberg Floats toward South Georgia, Putting Wildlife

慢速美语 - 科学新闻 Huge Iceberg Floats toward South Georgia, Putting Wildlife at Risk

原文：

The world’s largest iceberg is floating toward the island of South Georgia in the southern Atlantic Ocean. Scientists fear the iceberg could crash into the island and block major feeding areas for a large population of penguins and seals.

The huge iceberg is named A68a. It broke away from Antarctica’s Larsen C ice shelf in 2017. It has since has floated toward South Georgia, a British overseas territory.

Satellite images show the iceberg has remained in one piece. It is estimated to be about 150 kilometers long and 48 kilometers wide. It is traveling at one kilometer an hour and is on a path to hit South Georgia in around 30 days.

The British Antarctic Survey says it is concerned that if the iceberg hits the island, it could prevent the penguins and seals from reaching food supplies.

Professor Geraint Tarling is an ecologist with the Antarctic Survey. He says right now is the time of year when seals and penguins spend a lot of time caring for their young. This means the distance that parents have to travel to find food is important.

"That means they have to go a lot further, they have to go around the iceberg, or to actually go further to find sources of food,” Tarling told VOA. “And that time is quite critical at this particular period of their life cycle.”

Ecologists say an iceberg crash would also disturb materials settled on the seabed, possibly polluting the surrounding seas. As the iceberg melts, it would also release large amounts of fresh water into the ocean. This could affect krill populations that are a major source of food for the island's wildlife.

Tarling says the iceberg could remain for 10 years and change the area’s whole ecosystem. "These are globally significant populations of these species. If these species fail in this particular area, then the numbers globally are going to go down quite dramatically," he said.

The breaking off of icebergs from Antarctica is a natural process. But the process is changing with climate change. "What we're seeing with models and some observations now is the rate at which this is happening is increasing. And so, this might become more of a usual thing into the future," Tarling said.

The iceberg also could damage South Georgia's valuable fishing industry. Fishers pay for the rights to catch Patagonian toothfish, icefish and krill in waters off the island.

Officials are hoping that changing weather patterns could direct the iceberg out into the open ocean, where it would, in time, break up and melt.

I’m Bryan Lynn.

Words in This Story

iceberg – n. a very large piece of ice floating in the ocean

shelf – n. a flat area of rock, sand, etc., especially underwater

disturb – v. to change something by moving it from its original position

ecosystem – n. everything that exists in a particular environment

species – n. a group of animals or plants that are similar and can produce off spring

dramatically – adv. very sudden or notable