Front

Which of the following is the most widely discussed impact of climate change: Increase in average sea level, Deforestation, Soil erosion, Public health?

Back

Increase in average sea level

Answer explanation

The most widely discussed global impact of climate change is the increase in average sea level. It is expected to rise because glaciers and ice sheets melt and oceans expand as they get warmer. The global sea level has risen by 100-125 mm over the past 100 years. Much of this could be attributed to temperature increases. It is estimated that the average global surface temperature would rise by 2 °C between 1990 and 2100, with the average rate of warming greater than any seen in the past 10 000 years. A warmer climate would lead to a very high sea-level rise, estimated to be about 500 mm by 2100.

Front

Which of the following greenhouse gases has the biggest impact on climate change? Water vapour, Methane, Carbon dioxide, Ozone

Back

Carbon dioxide

Answer explanation

Carbon dioxide. Water vapour is the most prolific greenhouse gas, but its levels are reasonably constant. Methane and ozone are much more potent greenhouse gases than carbon dioxide, but they’re present in smaller quantities. Burning of fossil fuels – carbon, oil, petroleum – has seen carbon dioxide levels in the atmosphere increase from 280 parts per million 200 years ago to 430 parts per million today.

Front

The Singapore Green Plan 2030 aims to achieve its long-term net zero emissions aspiration by 2030.

Back

False

Answer explanation

The UN’s Global Roadmap sets out milestones the world must reach to achieve net-zero emissions by 2050.