Why are sea levels rising?

Sea levels are currently rising for two main reasons.

  1. Water in the oceans is expanding. This is the first and by far the greatest reason, due to the rising average world temperature.
  2. Melting of the ice caps and glaciers. The second and more minor reason at the moment is due to this melting putting more water into the oceans.
A: Sea level rise is rapidly becoming a bigger and bigger issue. Sea level rise is caused by global warming which in turn is caused by the addition of greenhouse gases into the atmosphere. These greenhouse gases, such as carbon dioxide and methane, don't stop much of the sun's light from hitting the earth as the wavelength of the light is too short. However when it is re-radiated from the earth's surface it has a longer wavelength. This is when some of it gets trapped by the greenhouse gases in the atmosphere. As more of the warm sun rays are trapped the earth's temperature rises.

This causes two major issues associated with sea-level rise.

  • One, the polar ice caps, mountainous glaciers and snow sources begin to melt at a faster rate than before and are replaced at a slower rate.
  • Second is that as the globe warms up all of the sea water will start to expand, So more water is being added through melting while the existing water is expanding.

This has resulted in predictions of 15-88 cm sea level rise over the next 10 years. That may not seem a lot, but many countries will be affected. Bangladesh and Holland are good examples. Much of their land has been reclaimed from the sea and currently sits either lower than sea level or within the 88 cm rise threshold. If the 88 cm rise is true, somewhere in the region of 5 million in Bangladesh alone stand to either lose their lives or be living in the sea.

A: Global warming

Sea levels are rising because the polar ice caps are melting and glaciers are receding, due (in most scientific opinion) to global warming.

A: The main reason for the sea levels rising is Global Warming.

This is when the polar ice caps in Antarctica and other places melt, and the ice is changed into water, which is done so in HUGE amounts at a time. Global Warming is melting the ice caps because the carbon emissions (outputs of petrol fumes, carbon dioxide into our atmosphere etc) are building up in the atmosphere. This is changing the natural greenhouse effect, which keeps us warm, into an enhanced greenhouse effect, which is causing global warming.

There are clearly noticeable temperature changes in the weather. Global Warming make the world hotter, therefore the Polar Ice caps melt faster, leading to the rising of the sea levels.

the greenhouse effect is causing the glaciers to melt which is make the sea levels rise.

Global warming causes glaciers to melt; the resulting water flows into the ocean and raises its level.

Due to increased amounts of greenhouse gases in the atmosphere (this is a result of the burning of fossil fuels as well as volcanic activity which also releases greenhouse gases), it is more difficult for the sun's rays to escape the Earth's atmosphere (this is due to the greenhouse gases acting as a 'blanket').

A consequence of this is that the temperature increases and the ice caps, as well as other stores of ice, melt at a faster rate. Therefore, there are higher volumes of water in liquid state which eventually reach the ocean and cause the sea levels to rise.

Global warming is actually a natural process as before the industrial revolution, greenhouse gases were still produced through cattle farming and volcanic activity. Nowadays global warming is amplified by human activity.