Polar Bears Could Face Extinction Earlier Than Thought

Polar bears could become extinct faster than predicted. That is because there is a shortage of food in their habitat and scientists have now found out that polar bears need more energy than previously thought.

As a result of global warming, Arctic ice is melting quickly, so that polar bears have to travel further in search of food. In a study that has spanned the last three years, scientists found out that polar bears have to travel one and a half times more than in the past.  As a result, they lose weight.

Experiments conducted with modern technology show how polar bears move and behave. High-tech GPS collars were put on 9 female polar bears. Their movements and energy consumption have been tracked over a period of 12 days. Results show that a few of them lost up to 10%of their weight.

According to the World Wildlife Fund, polar bears spend half of their time hunting for something to eat. They rely mostly on young seals as the main source of food, but the seal population is getting scarce because of the melting ice.

A polar bear needs about 12000 kilocalories a day to stay healthy and even more to put on the body fat it needs to survive the winter months.

Over the past ten years, the number of polar bears has declined by 40%. Ice on their habitat, Arctic Sea ice is decreasing at a rate of 14% per decade.  It is currently at its lowest level in 40 years.


Polar bear feeding on a dead seal
Polar bear feeding on a dead seal – Image: AWeith


  • according to = as reported by …
  • behave = act in certain situations
  • body fat = here: the fat an animal needs to protect itself from the cold weather
  • collar = band of leather or plastic that is around an animal’s neck
  • conduct = carry out
  • currently = at the moment
  • decade = ten years
  • decline = to go down
  • decrease = become lower
  • energy consumption = the amount of energy you need and use up
  • extinct = to die out and not exist anymore
  • global warming = increase in the atmosphere’s temperature caused by more carbon dioxide and other gases
  • further = a longer distance
  • GPS = system that shows where your position is on earth through a system of radio signals
  • habitat = natural home of a plant or animal
  • lose weight = become thinner
  • melt = when ice turns into water
  • predict = to say that something will happen before it does
  • previously = at an earlier time
  • rely = here: eat
  • scarce = not very much left
  • scientist = person who is trained in science and works in a lab
  • seal = large sea animal that eats fish and lives near coasts
  • shortage = not enough
  • source = where something comes from
  • span = period of time between two events
  • study = piece of work that is done to find out more about a subect
  • survive = stay alive
  • track = monitor, watch closely
  • World Wildlife Fund = organisation that wants to protect the environment and save animals and plants



Bleaching Endangers World’s Coral Reefs

A recent study shows that the world’s coral reefs have been showing signs of strong bleaching due to global warmingIn the 1980s bleaching was rare, occurring about once every 25 years. Now the rate has risen to about once every five years. Environmentalists predict that by 2050 bleaching will happen every year or two.

Bleaching is caused when warm water breaks down the algae inside the reefs. They provide food for the corals and keep them healthy. When algae fall off, corals lose their colour and can die within a short period of time. Even if the water surrounding the reefs gets colder again it may take years for the damaged reefs to recover completely.

While bleaching is especially a problem in the waters of the Carribean Sea and Western Atlantic, reefs around Australia and South Africa have hardly been hit. In addition to the warming temperatures of the oceans, coral reefs are also endangered by pollution and overfishing.

Coral reefs are an important ecosystem. They are home to 25% of all marine species and provide a  habitat for countless types of fish. Reefs protect coastal regions from flooding and tidal waves. In addition, coral reefs are tourist attractions that lure millions of people every year.  The tourist industry around the Great Barrier Reef in Australia, for example, is worth about 5 billion dollars a year.


Healthy coral on the left and bleached coral on the right
Healthy coral on the left and bleached coral on the right


  • billion = a thousand million
  • bleaching = to make something pale or white; when an object loses its colour
  • break down = to change its structure
  • Carribean Sea = sea between North and South America
  • cause = the reason for something; why something happens
  • countless = too many to be counted
  • due to = because of
  • ecosystem = all the animals and plants in a certain area and the way they live together
  • endangered = to be in danger
  • environmentalist = a person who cares about the world around us
  • especially = above all
  • global warming = when the temperatures in the atmosphere get higher because of increased amounts of carbon dioxide
  • habitat = place to live
  • in addition = also
  • lure = attract; here: bring people to the area
  • marine species = animals and plants that live in the oceans
  • occur = happen
  • overfishing = when you take too many fish from the sea so that the overall number of fish becomes too low
  • pollution = when water becomes dirty so that it cannot be used anymore
  • predict = to say that something will happen in the future
  • protect = keep safe
  • provide = give
  • rare = not very often
  • recent = a short time ago
  • recover = to become as healthy as they were before
  • sign = to show that something is happening
  • study = a piece of work that is done to find out more about a certain topic
  • surrounding = around
  • tidal wave = very large ocean wave that flows over land and destroys things




NASA Software Shows How Sea Level Rises Affect Cities

NASA scientists have created a new software program that can show how cities in coastal regions are endangered by flooding and sea level rise caused by global warming. The simulation shows how 300 coastal cities will be affected in the next century.

The software was developed by  NASA’s Jet Propulsion Laboratory. It calculates which ice sheets and glaciers are melting and how the additional water influences coastal regions. It takes into consideration the rotation of the Earth as well as the influence of gravity. The results are surprising. Sea levels will actually decrease around cities closer to ice masses, while the biggest rises will occur through ice caps that are farther away.

New York, for example,  will be most affected by melting ice caps in northeastern  Greenland. Sydney, on the other hand,  will actually be influenced by parts of Antarctica that are far away from Australia’s city.

The software aims at helping city planners prepare for sea level changes within the next few decades and how to keep ocean water out.

A climate report published this week shows that, since 1900, global sea levels have risen by about 20 cm, with half of the rise occurring in the last 25 years. Projections show that by 2100 ocean levels will rise by an average of 1 metre, however, the rise will not affect all coastal areas in the same way.


Ice Sheet in Greenland -
Ice Sheet in Greenland – Image: Christine Zenino


  • actually = in fact
  • additional = extra
  • affect = change
  • aim = here: what it wants to do and who it wants to help
  • average = here: evenly spread out across all oceans
  • calculate = here: find out how much something will change by using numbers
  • century = a hundred years
  • coastal = where land meets the sea
  • decade = ten  years
  • decrease = go down
  • develop = create , make
  • endangered = to be in danger
  • flooding = when land becomes covered with water
  • glacier = very large mass of ice which moves down a valley
  • global = worldwide
  • global warming =  the increase in the world’s temperatures by higher amounts of carbon dioxide in the atmosphere
  • gravity = force or power that causes something to fall to the ground and stay there
  • ice cap = large mass of ice
  • influence = change
  • NASA = National Aeronautics and Space Administration = American space agency
  • occur = happen
  • prepare = get ready for something
  • projection = calculation about what something will be in the future  based on the information we have now
  • publish = to make information for everyone to see
  • rise = to go up
  • rotation = the Earth’s spin  around its own axis
  • sea level = the average height of the sea
  • scientist = a person who is trained in science and works in a lab
  • simulation = here: software that shows how something could happen in the future
  • take into consideration =  here: to use  certain factors when you run the programme

Massive Hole Discovered in Antarctic Ice

Scientists have discovered a gigantic hole that has reappeared in the Antarctic ice. It is about the size of the Netherlands and is located around the Weddell Sea.

In the 1970s climatologists found a similar hole at almost the same spot. At that time  they didn’t have the observation equipment that they have now, so they couldn’t study the hole closely enough. After a few years it disappeared . Last year, the hole came up again.

Researchers cannot explain how the hole emerged.  One theory is  that warmer salt water from deep under the Antarctic ice sheet  may have come up and mixed with cold water near the surface, thus , melting the ice sheet above.  Normally a thick layer of ice covers Antarctica at the end of the  southern winter. Scientists also claim that it may be connected to climate change and global warming.

Such a hole in the ice is called a polynya.  Although not totally uncommon, it is strange that the hole in the Antarctic ice has appeared very far from its edge . Usually such holes are found in coastal regions.

Climatologists are not sure whether the hole will have an impact on the water temperature in the world’s oceans. If warmer water continues to surface to the top of the hole it may stay there for a longer period of time because it would then be difficult for ice layers to form.

Severe weather conditions during the Antarctic winter make it difficult to find holes in the ice . This is the second time in two years that such a hole has emerged , although last year’s was not that big.


Antarctic Ice Shelf
Antarctic Ice Shelf


  • although = while
  • claim = to say that something is true even if you cannot prove it
  • climatologist = person who studies the weather and how it changes the climate on earth
  • coastal = where land meets the sea
  • disappear = go away
  • discover = to find something that has not been there before
  • edge = the part of an object that is furthest from the centre
  • emerge = come out  from somewhere
  • equipment = the tools or machines you need to do something
  • gigantic = huge; very big
  • global warming = the increase in the temperature of the atmosphere
  • ice sheet = area of thick ice that covers the North and South Poles
  • impact = influence, change
  • layer = material or substance between two other things
  • reappear = to come again, after it has gone away for some time
  • researcher = a person who studies a subject in order to find out more about it
  • scientist = a person who is trained in science and works in a lab
  • severe = bad, extreme
  • similar = almost the same
  • size = how big something is
  • surface = the top layer of something
  • thus = therefore; that is why
  • uncommon = unusual, strange