環(huán)球英語 — 119：Sign Two: Polar Bears
Voice 1
Thank you for joining us for today’s Spotlight. I’m Rebekah Schipper.
Voice 2
And I’m Joshua Leo. Spotlight uses a special English method of broadcasting. It is easier for people to understand, no matter where in the world they live.
Voice 1
Siberia. It has one of the most severe climates in the world. This northern part of Russia makes up about fifty-six percent [56%] of the country. And it is mostly covered with a thick layer of permafrost, or frozen earth. Most of the lakes and rivers are frozen for much of the year.
Voice 2
But scientists have recently observed melting of Siberian rivers and lakes. They are concerned. The temperatures in Siberia seem to be rising. The scientists are especially concerned about the melting of bogs, the wetlands. They have observed the bogs releasing methane gas as they melt.
Voice 1
Methane gas is similar to carbon dioxide. Both are harmful to the environment. Scientists have linked these gases to an increase in the effects of global warming. One of those effects is increasing temperatures. Clearly, rising temperatures would cause more bogs to melt. As they melt, they will release more methane into the atmosphere. One scientist said
Voice 3
“If a high release rate of a harmful gas is being caused by rising temperatures that will in turn cause still higher temperatures.”
Voice 2
This is the second program in a series about the physical signs of global warming. People all over the world are seeing evidence of climate change. Take a look around. Do you see any of these signs where you live?
Voice 1
Today’s sign: the changing lives of Polar Bears.
Voice 2
Churchill Manitoba, a small town in northern Canada, is thousands of kilometres away from Siberia. In fact, Churchill and Siberia are separated by the Atlantic Ocean! But, they are experiencing similar problems. Their temperatures seem to be rising at a dangerous rate. Their icy lands seem to be melting. People and animals are beginning to feel the affects of these rising temperatures.
Voice 1
During the summer the population of Churchill is about six thousand [6,000] people. But, during the winter, the population increases greatly. In the winter, thousands of people come to visit Churchill. They come to see the polar bears.
Voice 2
For thousands [1,000s] of years these large white animals have been walking the same path. You see, Churchill sits on the waters of the Hudson Bay. Every year, at the start of winter, ice forms north of town. Once it forms, the polar bears walk onto it. There, they hunt for smaller animals all winter long. They fill their stomachs with enough food to last them through the summer!
Voice 1
In the spring the ice begins to melt. The melting ice floats south of Churchill. Here the bears leave the ice. They return to dry land for the spring and summer months. They stay on land until the following winter.
Voice 2
When the ice starts to form again, the bears must travel through the town Churchill to reach it. They travel from south to north. Imagine seeing a large polar bear walking through your town! Well, many people do not want to just imagine it. They want to see it for themselves. So, they travel to Churchill to watch the bears march through the town.
Voice 1
The people of Churchill love the polar bears. They feel honoured to have the bears come through their town. And the polar bears help the people of Churchill. When visitors come, the townspeople can make money.
Voice 2
That’s right. The visitors pay money to eat, sleep, and spend time in the town. And they pay money to take vehicles out onto the ice. When they are on the ice, polar bears will come to say hello. They smell the vehicles and look at the people. Guides make sure that both the people and the polar bears remain safe.
Voice 1
But, rising temperatures are starting to threaten the lives of the polar bears. Because of warmer temperatures, the water is frozen for a shorter amount of time each year. The polar bears must spend more time on land. They do not have as much time to hunt in the winter.
Voice 2
Some polar bears try to remain on melting ice. When the ice melts they are too far away from land. And they drown.
Voice 1
Other polar bears are starting to trouble the people of Churchill. The bears are hungry. So, they go into the town looking for food. Sometimes the bears act aggressively. They attack.
Voice 2
People of Churchill are worried.
Voice 4
“You know, the earth is warming. And so there are some dangers in climate change...The bears, for instance, how will they survive...?”
Voice 5
“I am worried. Because the bears are the lives of a lot of people in this town.”
Voice 6
“We love this place. We learn to live with what is happening. Except for this warm weather! We just do not understand what the heck is going on! And really I believe it is the big cities down south causing the warmer weather.”
Voice 2
Many people in Churchill believe the bears will find a way to survive the warming weather. They say that people can change to fit new environments. So, bears can change too. They think that bears will just change their diets. They will learn to eat plants and berries instead of meat.
Voice 1
But, Dr. Jane Waterman does not agree. She has studied polar bears for many years. She says that bears do not have enough time to change their genetics. They do not have time to create a new diet.
Voice 7
“Natural selection can happen very quickly in bacteria because they can reproduce in twenty [20] minutes. Polar bears live twenty [20] or twenty-five [25] years. That means for changes to happen genetically it is going to take a little bit of time. And time is something the bears do not have. If there is no sea ice in the Hudson Bay, then there are no bears. If there is no sea ice, you cannot have bears.”
Voice 2
The Churchill bear population has fallen more than twenty [20] percent in the past seventeen [17] years. Researchers link this loss to the lack of sea ice. And they predict that temperatures will continue to rise.
Voice 1
Climate change is affecting many parts of our world. We can find signs in the mountains, deep in the waters, in the behaviour of animals, and in the lives of people. Please listen for more programs about the early signs of climate change. Let them remind you that the earth is ours to care for.
Voice 8
“Let the sea resound, and everything in it, the world, and all who live in it. Let the rivers clap their hands, let the mountains sing together for joy.” [Psalm 98]
