Intuitively, the first consequence of the melting ice that one thinks of is the rise of the waters and the level of the oceans. The phenomenon has already been visible for decades and it will continue inexorably. One more bad news, it is not the only consequence …
What are the consequences of melting ice caps, pack ice and glaciers on the planet. I have already tried to explain in this article the causes of melting ice. So now let’s move on to the consequences …
An inexorable rise in water
Global warming therefore causes the ice to melt, which causes the sea level to rise. Why this rise in water levels? The logic is relentless, all continental ice (snow, glaciers, ice caps) keep melting. This surplus of water which comes from the continent arrives in the ocean, which causes an increase in its level.
This rising waters reached 18 cm between 1870 and 2000 and the phenomenon has accelerated over the past 20 years, with an increase of 6 cm. forecasts for 2100 range from 40 to 80 cm extra according to the different scenarios considered.
Oceanographic reports show that the level of the oceans has high 18 cm on average in the world between 1870 and 2000. The IPCC, the UN-sponsored international panel on climate change, says rising sea levels are inevitable: average sea and ocean levels could rise up to 82 cm by 2100 if nothing is done to limit greenhouse gas emissions.
If this estimate holds, certain French coastal areas low (Vendée, Camargue, Flanders…) will be impacted. In the Tuvalu archipelago, the islands are already under attack from all sides by rising sea levels.
All of these assessments are based on scientific work, both factual and objective. There is no bias in these reports: it is an analysis of the data which aims toconsider scenarios for the future.
According to the most extreme scenarios (not emanating from the IPCC), the total thaw in Greenland andAntarctic could, over several centuries, lead to a rise in sea level of nearly 70 meters.
Ice floes and freshwater reserves
On the other hand, contrary to popular belief, the melting sea ice does not contribute to the rising waters. Pack ice is a layer of ice that forms on the surface of the sea when the temperature drops. Now the volume occupied by ice under the sea surface is exactly the same than that of ice once melted.
This is what the Archimedes principle that you necessarily know by heart: “any body immersed in a liquid undergoes a vertical upward thrust, equal to the weight of the volume of liquid displaced”.
The second consequence of melting ice is the inevitable decrease in solid freshwater reserves which, in summer when it is hot, feed the reserves of liquid fresh water.
The melting of glaciers constitutes an essential source of drinking water and irrigation water for several hundred million people.
When the melting of ice caps and glaciers accelerates, freshwater resources decline more quickly. This increases the risk of scarcity and conflict related to water in these territories.
Seven regions of the world have been identified and classified as “at risk” by scientists: these are Alaska, the Canadian Arctic Archipelago, the Russian Arctic, Iceland and the Norwegian Archipelago of Svalbard, the Southern Andes and the Himalayas.
The consequence we don’t think about
More subtle and less intuitive, the other dramatic consequence of melting ice is linked to the phenomenon of reflection of solar energy, measured by albedo.
THE’albedo is the reflective power of a surface, that is to say the ratio of reflected light energy to received light energy. The clearer a body, the more reflective it is and the stronger its albedo. Conversely, a dark body has a low albedo because it absorbs more of the Sun’s rays.
Thus, a cloud with an albedo of 70% will reflect back to space 70% of solar energy that he received. Depending on its orientation, its color, a surface will retain more or less the radiation received.
Take some examples : sea ice reflects more than half of the radiation, ocean and forest only 5 to 10%, snow returns 60 to 90% and meadows 18 to 25%.
What does that mean ? Less ice means less reflection, so more solar energy that accumulates and stays on Earth, so more warming and less ice, etc. We meet in a vicious circle from which it is impossible to escape!
This is the consequence of melting ice that we do not think about. The global albedo of a region decreases: as the solar energy returned naturally to space decreases, the global temperature the region is increasing, which amplifies the phenomena of global warming and melting ice.
It might sound a bit abstract if you live far from coastal areas and glaciers but all of these consequences overlap and will have an impact far beyond the regions where these phenomena occur.
The rising waters will have a erosive impact on the coasts. The shoreline will gradually recede making coastal dwellings more vulnerable. During storms and cyclones, inhabited areas will be more exposed to the phenomena of marine submersion, which will amplify the damage from flooding.
