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.
Statement 1 is correct: At such high temperatures, tipping points like widespread forest dieback and permafrost thaw would release vast amounts of stored carbon, causing the land to emit more carbon than it absorbs. Statement 2 is correct: Scientific consensus indicates that even at 2°C of warming, over 99% of coral reefs are expected to be lost. A 3°C rise would ensure their catastrophic and widespread collapse. Statement 3 is incorrect: The word "All" is an extreme overstatement. While many wetlands would be severely damaged or lost, it is not scientifically plausible that every single one would disappear permanently. Statement 4 is incorrect: The term "anywhere" is an exaggeration. While global food production would be devastated, cultivation would not become impossible everywhere; it might shift to new, higher-latitude regions.