Professor Will Steffen, head of the climate change unit at the Australian National University and science adviser to the Federal Government in Australia, says that sea levels around the world could rise by 4 meters this century. He also claims that the scientific community underestimates how fast our climate is changing.

“The evidence over the past 12 to 18 months suggests that we have underestimated how fast this aspect of the earth’s system can change,” he said.

“We see things happening much faster than we thought.”

Professor Steffen raised this concern at the Coast to Coast Collaboration Conference in Darwin where he said “a four-metre rise could have devastating effects.”

It is a fact that global warming affects the icebergs in a most dramatic way. The greenhouse effect is to be blamed, as it is the cause of global warming. How does that make the sea level rise? Well first of all when water is heated it expands. But also since an iceberg is 99% ice it starts to melt as soon as the temperature is over 0 degrees, making it just too easy for the icebergs to start melting.

Icebergs are huge, the largest one is 12,000 cubic miles. So, if you were to melt it you would get an awful lot of water. Also there are many, many icebergs on earth, so if all of them melted you would have millions of gallons of water. Icebergs won’t melt completely, but enough to make the sea level rise quite a bit.

Scientists used to say that by the end of the century the sea may have risen up to three centimetres. That didn’t sound a lot, but it really is. And now, scientists have started to realise that their first calculation was far too positive for our case, since nothing is done to stop global warming and the process of melting ice becomes quicker and quicker.

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