Ice-free Seasons to threaten Polar Bears

ielts reading

The future for polar bears is grim if Arctic sea ice continues shrinking at current rates, suggests new research from the University of Washington.
The fact that sea ice in the Arctic is disappearing as global temperatures rise is not new information. But this study, published in science journal “The Cryosphere” Wednesday, is an important landmark in that it’s “polar bear-centric,” researcher Kristin Laidre of the UW’s Polar Science Center told The Huffington Post.
“We looked at what metrics have been shown to be most meaningful for polar bears,” she said.
Using satellite data collected over 35 years, the researchers analyzed how long “good quality” sea ice was available each year in each of the 19 Arctic regions where polar bears live.
“[The ice] starts forming in the fall in the Arctic, and then it peaks in the spring and starts breaking up and receding through the summer,” Laidre said.
Between 1979 and 2014, the researchers found, the time span between the spring break-up and the fall freeze has increased, on average, between three to 9 weeks. And that’s bad news.
“For polar bears, ice is basically their platform of life,” she said. “They use ice to find prey, they use ice to find their mates, to breed, to travel.”
Polar bears hunt seals by waiting near the edge of ice and waiting for the seals to surface. It’s especially crucial for mothers that have recently given birth to have access to the ice.
“A female goes into a maternity den when she’s pregnant in the fall and she stays in that maternity den until spring,” Laidre said. “And then she comes out of that den around March and she hasn’t eaten anything for 6-7 months … she comes out of that den with very small cubs and is very thin and needs to find food.”
In some parts of the Arctic, bears spend the ice-free months on land, where they’ll scavenge for food items like carcasses and bird eggs, but they’re “largely fasting” during those months, she said. In other parts where the ice doesn’t disappear completely, they follow the ice as it recedes north, over deeper water where fewer seals can be found.
Either way, it’s crucial that the bears build up their fat reserves while the ice is abundant and they have good access to prey.
(Source: http://www.huffingtonpost.com)

* Vocabulary:

-  shrink (v): become smaller and smaller.
e.g.: Those clothes will get shrunk if you iron them with high temperature.
- time span (exp): a length or period of time  between two events or more.
- go into maternity den (exp): a place that an animal shelters and hide itself when she is pregnant.
e.g.: His cat, Donnie , is staying in her maternity den. So, you'd better go past her den quickly or you are badly scratched.
* NotesReserve (n) vs Reservation (n):
a. Reserve is something that you keep in case or until you need in the future.
e.g.: - We have some food reserves in case of flood.
        - She has some money in reserve.
b. Reservation is an activity or an arrangement that somebody booked a seat or place for you, who had them do so.
e.g.: - We would like you to make a reservation for 5 this evening.
Share on Google Plus

About tri vo kim

Thank you for spending your precious time to have flipped thru lessons. I am doing my best to upload more and more selective articles with further elaboration of vocabulary and structure. Bookmark my Blog for keeping updated with latest lessons or drop me some lines via my BBM: 2C275701