[Gondring]

Have you run the calcs on that?

[Vigilanteman]

Consider these facts (available from National Geographic):

1. If all the ice in the world was melted into water (some 5.5 million cubic miles) (23 million cubic kilometers), in all, the oceans would rise 1.7% percent, or about 180 feet (60 meters).

2. The Greenland ice shelf alone covers about 750,000 square miles or about 100 times the surface area of the proposed Qatarra Sea.

3. The weight of the ice shelf has depressed the land it is on to an average depth of about 1000 feet below sea level.

4. The average glacier is porus and about 10 times the width (minimum)in ice and snow pack as the water equivalent. Many geologists put the ratio much higher, but we'll keep it a factor of 10 for simplicity.

5. The average depth of the Greenland ice cap is 3.2 km or about 10,500 feet.

6. Divide this by the factor of 10 for water equivalent and you have 1050 feet, 1000 feet of which is absorbed into the Greenland basin, so 50 extra feet of water x 750,000 square miles.

7. Average depth of the 7500 square mile Qatarra Depression is 133 meters or 436 feet.

8. Recall that water evaporates quite rapidly from this desert region. The links on the Qatarra hydroelectric project indicate evaporation will require at least 10 times the water-inflow to maintain the natural sea level, thus 7500 square miles x 10 x 436 feet to keep the basin filled to capacity.

9. 50 feet is .0095 miles x 750,000 square miles = 7100 cubic miles of excess water from Greenland's ice caps.

10. 436 feet is .083 miles x 7,500 square miles x 10 (evaporation factor) = 6225 cubic miles of water capacity available in Qatarra Depression.

11. Meaning that-- if all of Greenland's ice caps melted, the Qatarra Depession could absorb all but 875 cubic miles or 12%. Of course, this model does not account for changing evaporation rates due to global warming. If the past is any guide, it would take about 18,000 years for a total meltdown of the Greenland glacier during which time much of the water would be absorbed by additional vegetation. Remember, a mere 2200 years ago, what is now most of northwest Africa was the Carthaginian province of Numidia, then a semi-tropic climate to the present day Sahara Desert, and a semi-arid (similar to the present coastal climate) about 120 miles inland of the present Sahara boundries. Vegetation (especially trees) store massive amounts of water.