The scientific view is that the increase in global temperature should not exceed 2°C above the pre-industrial level. If the global temperature increases beyond 3°C above the pre-industrial level, what can be its possible impact/impacts on the world?
- 1.Terrestrial biosphere tends toward a net carbon source.
- 2.Widespread coral mortality will occur.
- 3.All the global wetlands will permanently disappear.
- 4.Cultivation of cereals will not be possible anywhere in the world.
Select the correct answer using the code given below:
- A.1 only
- B.1 and 2 only
- C.2, 3 and 4 only
- D.1, 2, 3 and 4
▶ Answer & Explanation
Correct answer: B. 1 and 2 only
A significant rise in global temperature, such as 3°C above pre-industrial levels, would drastically alter ecosystems. The terrestrial biosphere could shift from a carbon sink to a source due to increased decomposition and reduced carbon uptake. Elevated sea temperatures and ocean acidification would lead to widespread coral bleaching and mortality. While wetlands would be severely impacted, the complete and permanent disappearance of all global wetlands is an overstatement. Similarly, cereal cultivation would be severely disrupted and reduced, but not become impossible worldwide.
Source: UPSC gs1 2014