This article looks at what changes may occur on the planet as the polar ice caps melt.
Image by blmurch via Flickr
Invariably, any length discussion about global warming will get around to melting polar ice caps. Since the end of the last large ice age, the amount ice at the poles has been getting smaller. This is indeed a matter for some concern although there is no definitive and accepted answer regarding the final results of polar ice cap melting. However, there are some things that seem to be agreed upon by those who spend their life trying to research this issue.
As the polar ice caps melt, the sea levels around the world will rise.
This is already happening. It is most pronounced in those areas that are built near the coasts but below sea level. The levees that keep the ocean back are constantly being repaired and enlarged to compensate for this rise in sea levels. Many communities that were at or slightly above sea level a century or two ago are finding themselves dealing with the problems created by going below sea level. Several European cities are in this situation. In the United Stated, New Orleans comes to mind as a city that is fighting this battle.
A total meltdown of the polar ice caps will add significantly to the sea levels.
Scientist estimate that if all of the polar ice were to melt, the oceans would rise by several feet. This much extra water would shave many square miles off of the earth’s land masses. In numerous places, the water would reach miles inland. This will create many problems with the need for populations to make major shifts from current coastal areas. The new coasts will already have people living there. The former coastal residents will likely have problems finding land and homes within the same region as they previously lived.
Additional water will bring more water vapor or clouds.
This is one of the areas of dispute. Many see this additional cloud coverage as trapping more heat closer to the earth’s surface and causing the temperature to continue to rise. Others see the clouds as shielding the sunlight from ever reaching the earth and creating another ice age. Those who endorse the ice age theory believe that the switch from a near tropical earth temperature to the frozen one will only require a decade or two to occur. Still others, see the melting with the resulting clouds as cooling the earth, refreezing the caps, and averting both the tropical and the frozen earth from occurring .
As huge quantities of fresh water enter the oceans, the salt levels will drop.
This is a big problem in the north Atlantic Ocean. A stream of water flows from south of the equator to the northern latitudes in the Atlantic. The water is warmed in the south. As it makes its way north, the surface water cools. Somewhere north of England, this cooled salt water does not freeze, but sinks to the ocean depths where it begins to circulate back toward the south. This process brings warm sea breezes to warm northern Europe including England. It depends on the salt content of the ocean to maintain this cycle without the water freezing when it hits northern cold.
A less salty ocean would freeze and stop this conveyor from delivering the warm water and climate to the north. This failure of the conveyor would result in a much deeper ice age striking the northern hemisphere. Because the region warmed by the ocean current would be frozen, centuries might be required to restore the ocean stream that now feeds this climate pattern.
There may be other more positive sounding results that are not often brought into these types of discussions.
As the world is warming areas like the Sahara Desert are expanding the size of the uninhabitable land on the Earth. Melting polar caps could cause the atmosphere to be so much more humid that rain would once again return to these arid regions. This prospect would add a considerable amount of real estate back into the equation when one considers the number and size of the world’s deserts. Temperatures would increase at higher elevations and atmospheric pressure should rise some too with the additional moisture content of the air. This could make some of the regions available to larger numbers of people and make up some more of the losses with more land for agriculture.