CRI听力:Global Warming Poses Challenge to Ecosystem in Arctic

Northeast Arctic cod, usually found in the Barents Seas, have been traveling up to the archipelago of Svalbard for the past three years.

Off the coast of Longyearbyen, a Norwegian city located just 1,300 kilometers from the North Pole, scientists are trying to figure out the impact the non-native fish species' appearance will have.

Professor Ole Arve Misund, once a fisherman and now marine biologist from the University Centre in Svalbard, is one of them.

"We are trying here to catch a Northeast Arctic Cod that we have seen on our echo-sounder. I had one just touching my gear now but it slipped away. So we know they are here, and they are coming because the water is warm enough for them to be here to feed."

Within just five minutes, Misund quickly gets his first catch of the day, which would not have been the case a decade ago.

Northeast Arctic Cod is a predatory species and one of the largest cod stocks in the world. In recent years, an increasing proportion of the mature cod has been caught north of the traditional spawning area.

Professor Misund suggests that the warmer climate has led to the cods' migration northwards.

"The last three years, we have had them (Northeast Arctic Cod) every autumn. They were recorded here before to a varying degree, but because of the warmer waters in recent years, we now see them every season. The waters are heating, and they are now so warm - 3 to 4 degrees Celsius - and it's possible for species that normally live further south to come all this way to feed."

Warmer waters in the Arctic Ocean, on one hand, help these fish grow faster. But on the other hand, it could make fish more prone to infection from sea lice and other diseases, while causing more severe storms.

Professor Misund says the northeast Arctic cod could destroy the habitat of local fish as well as the Arctic's ecosystem.

"They are, of course, reducing the number of Polar Cod. They are eating them of course. But they are mainly feeding on krill and basic organisms. So of course they are making an impact on the other fauna, but I mean - that's the way nature is."

Unlike northeast Arctic cod, polar Cod exists in the region all year around, and is an important food source for seabirds, seals and whales.

The large reduction of its stock could harm the food chain, thus destroying the fragile balance of the ecosystem.

However, for local residents relying on planes to ship in fresh food, more cod in the fjord turns out to be a bonus.

Lars Frode Stangeland is a local skipper.

"The locals, of course they feel happy, they get cod and there is more and more fishing every year. So we get a lot of cod and haddock."

The World Meteorological Organization has warned that the earth's wild weather this year is breaking annual temperature records due to man-made global warming.

As such, the international community is waiting to see whether global leaders can keep their promise of keeping global warming within 2 degrees Celsius above the pre-industrial level, at the forthcoming Paris Climate Conference.

For CRI, I am Wang Mengzhen.