If, God forbid, current human lifestyle (i.e.
CO2 emissions,
rainforest depletion, etc.) leads to global
deglaciation; or even if there is a sudden increase in global temperature due to
extra-terrestrial factors regardless of human activity (i.e. increase in burning temperature of the sun, change in
axial tilt of the earth, etc.) causing
global warming; then humans (and, let us not forget, our coexistent
flora and
fauna) are in for an enormously catastrophic event. We, collectively referring to the flora and fauna, would be forced to disobey our nature to adapt slowly to our changing
environment (see
Theory of Evolution) and would have to execute life-style changes rapidly. It is estimated that if complete deglaciation were to occur,
sea level would rise 80 meters. This would be
detrimental, to say the least, to the some 70+ percent of
the world's human population living in marine-coastal regions.
Needless to say, this would be a problem that would need to be addressed if it arose, and as unlikely as
complete deglaciation is, I think it is a possibility that should be addressed.
Presently, as we are
warming up since the last large scale glaciation approximately
12,000 years ago, the volume of Earth's
ice caps and
glaciers total nearly 3,400,000 cubic
kilometers(km
3). The approximate distribution is as follows:
Antarctic Ice Sheet: 31x10
6km
3 (91.4%)
Greenland Ice Sheet: 2.8x10
6km
3 (8.3%)
Other Glaciers: 0.12x10
6km
3 (0.3%)
I'd like to propose a solution to this problem if it were to ever arise:
---------------------------------------------
For simplification purposes, we'll say that the average
density of the ice in these glaciers and ice sheets is 900 kg/m
3 (whereas the density of
water is 1000 kg/m
3). The relationship between
mass, density, and
volume, as the great
physicists before us have shown, is as follows:
Mass(M) = Density(D) x Volume(V)
Ergo...
M
ice = M
water (Whereas mass of
ice and water will be the same, their respective volumes will differ)
M
ice = D
ice x V
ice
M
water = 900kg/m
3 x 3.4x10
15m
3
M
water = 3.06x10
18 kg
The mass of water being established, we can now find the water's volume...
3.06x10
18 kg = 1000 kg/m
3 x V
water
V
water = 3.06x10
15 m
3
Relatively speaking, this is a
huge amount of water. I mean, we're talking 3,060,000,000,000,000 cubic meters of water! If we had no way to stop the ice from melting so rapidly and we were bound, sometime in the
future, to have that
tonnage of additional water in earth's
oceans, then I see two possible scenarios: 1) There would be a mass
migration inland, that is, to higher ground as the water rises, or 2) there would be somewhere for the water to go. Given the well-established nature of our
coastline cities, the former would be difficult. The latter is what I'd like to focus on.
Presently, citizens of the world have
acres upon acres of unused (for the most part) land in northern
Canada and in
Siberia. In addition to these lands, there is a large amount of land under the Greenland and Antarctic ice sheets that would be uncovered in the case of deglaciation. Geologists know that to change the sea level
eustatically, neglecting the daily
tides, the amount of water must change or the volume of the ocean basin must change. My proposal, if the amount of additional water could not be lessened significantly during deglaciation, or if the rapid climate change based on our lifestyle cannot be reversed, is that we dig enormous basins in the aforementioned land areas to host the extra water.
Certainly the basin would have to be quite big. And obviously this would be an
epic endeavor that would need the cooperation of the world. The tallest peak in Canada,
Mount Logan, is just over 6 km above sea level, but most of the country is under 0.5 km above sea level. I'd
imagine that most of the ground is
bedrock, also. I'm sure our
engineers could work out the
mechanics of it and the effects on the
water table and what not, but if we dug a hole in northern Canada that was 300 meters(0.3 km) deep below sea level and, say, 800,000 meters by 800,000 meters(800 km by 800 km), we would have a basin that could hold 1.92
14 cubic meters of water, more than enough to accomodate the increased volume of ocean water. Of course, there would be a massive amount of
dirt to remove even before we could start digging below sea level, and there would need to be somewhere to go with all that dirt and bedrock. We would have to build the first
man-made mountains (besides the
landfills) with all that dirt.
Now,
Canada was just used as a
hypothetical, and I don't mean to offend any
Canadians by making their land seem good only as an ocean floor. I think we could divide the size of this hole among each continent and create 7 new mini-oceans.
Hopefully, deglaciation wouldn't occur outside its natural cycle, but if it did, this is just a possible solution. I know--it seems absurd; but then again, it may just work...