Climate Change Quiz Contest

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1. If the 1.5℃ goal in the Paris Agreement is to be achieved, the world has to achieve carbon neutrality (i.e. net-zero emissions of carbon dioxide) in the middle of this century.
2. Approximately a quarter of all anthropogenic carbon dioxide emissions has been absorbed by the surface ocean.
3. The atmospheric concentration of carbon dioxide continued to increase and reached 417.9 ppm in 2022. This concentration is unprecedented in at least the past 2 million years.
4. Methane is the second most significant driver of global warming following carbon dioxide.
5. Global surface temperature has increased faster since 1970 than in any other 50-year period over at least the past 2,000 years.
6. Global surface temperature was 1.09℃ higher in 2011-2020 than 1850-1900.
7. The frequency of heavy precipitation events has increased since the 1950s over most land area.
8. The Arctic is likely to be practically sea ice free in September at least once before 2050.
9. Which of the following are the primary causes of global mean sea level rise?
       (i) Melting of sea ice;    (ii) Thermal expansion of seawater;    (iii) Melting of land ice
   Answer: (ii) and (iii)
10. Global mean sea level has risen faster since 1900 than over any preceding century in at least the past 3,000 years.
11. Which of the following leads to the increases in agricultural and ecological droughts in some regions?
    Answer: Increased evapotranspiration
12. Relative to 1995-2014, the likely global mean sea level rise by 2100 is 0.44 - 0.76 m under the intermediate greenhouse gas emissions scenario (SSP2-4.5).
13. At 2℃ of global warming, heat extremes would more often reach critical tolerance thresholds for agriculture and health. The frequency of a 50-year extreme temperature event (i.e. the chance of annual occurrence is about 2% on average) over land defined in 1850-1900 is projected to increase to about 13.9 times when global warming reaches 2℃.
14. Approximately half of the species assessed globally have shifted polewards or to higher elevations.
15. Up to 14% of terrestrial species could face very high risk of extinction at a global warming level of 1.5℃. The percentage could reach 48% at a warming level of 5℃.
16. The population potentially exposed to a 100-year coastal flood (i.e. the chance of annual occurrence is about 1% on average) is projected to increase by about 20% if global mean sea level rises by 0.15 m relative to 2020 levels.
17. Projected increase in direct flood damages is higher by up to 3.9 times at 3℃ compared to 1.5℃ global warming without adaptation.
18. The largest growth in global net anthropogenic greenhouse gas emissions in 2019, relative to 1900, occurred in carbon dioxide from fossil fuels and industry.
19. To limit global warming to 2℃, global greenhouse gas emissions must be reduced rapidly and deeply throughout 2030 to 2050.
20. Which of the following action(s) can help combat climate change?
            A. Save energy
            B. Adopt a low-carbon and pro-green lifestyle
            C. Drive less
            D. All of the above