Mount Cook: Shrinking mountain loses 30m from height

            New Zealand's tallest mountain has shrunk by 30m but is still the highest in the country.

            A new study of Mount Cook - also known at Aoraki - shows it is 3,724m (12,217ft) down from 3,754m. It's thought that the top has been worn away after a collapse of rocks and ice in 1991 left the summit open to the elements.

            Scientists used GPS and photos taken at the time to find out more about the mystery of the shrinking mountain.

           

            Dr Pascal Sirguey of the Otago National School of Surveying which carried out the assessment said: "By carefully studying photos taken after the collapse, it appears that there was still a relatively thick ice cap, which was most likely out of balance with the new shape of the summit ridge. As a result the ice cap has been subject to erosion over the past 20 years."

True or false?

1. The top of the mountain was covered with ice.

2. The loss of height followed the earlier collapse.

3. There is no photographic record of the mountain.

4. The collapse made the ice cap unstable.

5. Scientists found the change to be mysterious at first.

6. Mount Cook is not the highest mountain.

7. Scientists are uncertain why the mountain has lost height.

8. The mountain remains the tallest in New Zealand.

Match the words below to their definitions

assessment / balance / collapse / elements / erosion / surveying

when something falls down because it is too heavy

weather, especially bad weather

when something is studied to determine its qualities

profession where people examine and record the features of an area of land so that it can be mapped

even distribution of weight that allows something to remain steady

when something is gradually damaged and removed by the sea, rain or wind

What is the missing word?

1. It appears that there was still a___________________thick ice cap.

2. The ice cap has been___________________to erosion over the past 20 years.

3. Mountains are___________________from the average sea level to the summit.

4. The height when a hill becomes a mountain___________________.

KEY

True or false

1. True

2. True

3. False

4. True

5. True

6. True

7. False

8. True

Vocabulary

collapse            when something falls down because it is too heavy

elements          weather, especially bad weather

assessment      when something is studied to determine its qualities

surveying          profession where people examine and record the features of an area of land so that it can be                     mapped

balance            even distribution of weight that allows something to remain steady

erosion             when something is gradually damaged and removed by the sea, rain or wind

What is the missing word?

1. relatively

2. subject

3. measured

4. varies