Question

Climatologist warn of a tipping point when global temperature trigger catastrophic events and rise levels rise more than 50 feets. What would cause the sea level rise so greatly and how much warmer does the world need to get for this tripping point to happen 

1. 1°C 

2. 3°C 

3. Melting of Greenland ice sheet 

4. thermal expansion of oceans 

Which of the above is/are correct? 

(a) 1 and 3 (b) 1 and 3 (c) 2 and 3 (d) 2 and 4

Answer 1

(c) Greenland ice sheet melt water, which moves to the sea under the ice in contact with the land surface, may transport solids or dissolved material such as iron to the ocean. Measurements of the amount of available iron in melt water from the Greenland ice sheet shows that extensive melting of the ice sheet might add an amount of iron to the Atlantic Ocean equivalent to that added by airborne dust. This would increase biological activity in the Atlantic.