The Climate Crisis – A Factfulness Quiz
(Questions & Answers)

1. Prologue

Comment: “The following short quiz requires knowledge of fundamental facts, predictions, and expert opinions regarding anthropogenic (human-caused) global warming. The questions were inspired by Professor Hans Rosling’s Factfulness Quiz on global health. He used to educate his students, but also the rest of society, especially decision-makers, on global health, but also on their pre-conceptions and biases using a quiz format. Thereby, he also  demonstrated the need for continued education to make the right decisions in a fast-changing world. Since climate change, also referred to as climate emergency, is considered the decisive question of our time, factfulness on this vital topic is strongly needed.

2. Quiz

2.1 Question 1 – Current carbon dioxide levels

Q1What was the average concentration of carbon dioxide [in parts per million, ppm] in the Earth’s atmosphere in May 2019?
Note: The measurement was taken at the Mauna Loa measurement station on Hawaii. Seasonal changes lead to decrease (around 6 ppm) of carbon dioxide concentration after May each year due to plant growth in the Northern Hemisphere.
A) 215 ppm
B) 415 ppm (correct)
C) 615 ppm
D) 815 ppm
ReferencesDr. Pieter Tans, NOAA/ESRL and Dr. Ralph Keeling, Scripps Institution of Oceanography (2019-06-23). Trends in Atmospheric Carbon Dioxide [Website, Data]. Website: https://www.esrl.noaa.gov/gmd/ccgg/trends/data.html, Dataset: ftp://aftp.cmdl.noaa.gov/products/trends/co2/co2_mm_mlo.txt

2.2 Question 2 – Safe carbon dioxide levels

Q2What average concentration of carbon dioxide [in parts per million, ppm] in the Earth's atmosphere is considered "safe"?
A) 150 ppm
B) 350 ppm (correct)
C) 550 ppm
D) 750 ppm
ReferencesHansen, J., M. Sato, P. Kharecha, D. Beerling, R. Berner, V. Masson-Delmotte, M. Pagani, M. Raymo, D.L. Royer, and J.C. Zachos, 2008: Target atmospheric CO2: Where should humanity aim? Open Atmos. Sci. J., 2, 217-231, doi:10.2174/1874282300802010217. URL: https://arxiv.org/abs/0804.1126

2.3 Question 3 – Future carbon dioxide levels

Q3What level of carbon dioxide concentration [in parts per million, ppm] in 2019 did the fossil-fuel company EXXON predict back in 1982?
Note: The carbon dioxide level according to Scripps CO2 measurements at Mauna Loa (cf Keeling curve) was 415 ppm in May 2019.
A) 120 ppm
B) 320 ppm
C) 420 ppm (correct)
D) 620 ppm
ReferencesExxon/Coordination and Planning Division (1982-04-01). C02 Greenhouse Effect – A technical Review (EC-11-5/A3), Retrieved 2019-06-18 from https://bit.ly/2WOwEG4.

see also: Hall, S. (2015-10-26). Exxon Knew about Climate Change almost 40 years ago. Scientific American. Available at https://www.scientificamerican.com/article/exxon-knew-about-climate-change-almost-40-years-ago/

2.4 Question 4 – Current temperature increase

Q4What was the global mean surface temperature increase [in ° Celsius relative to the pre-industrial age, here: average from 1880 to 1900] in 2018?
A) 0.5° Celsius
B) 1.0° Celsius (correct)
C) 1.5° Celsius
D) 2.0° Celsius
ReferencesNOAA National Centers for Environmental Information, State of the Climate: Global Climate Report for Annual 2018, published online January 2019, retrieved on June 23, 2019 from https://www.ncdc.noaa.gov/sotc/global/201813.

2.5 Question 5 – Safe temperature increase

Q5What is the global mean surface temperature increase [in ° Celsius relative to the pre-industrial age, here: average from 1850 to 1900] which is considered "safe" based on natural history?
A) 0.5° Celsius
B) 1.0° Celsius
C) 1.5° Celsius (correct)
D) 2.0° Celsius
ReferencesIPCC, 2018: Summary for Policymakers. In: Global warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty [V. Masson-Delmotte, P. Zhai, H. O. Pörtner, D. Roberts, J. Skea, P.R. Shukla, A. Pirani, W. Moufouma-Okia, C. Péan, R. Pidcock, S. Connors, J. B. R. Matthews, Y. Chen, X. Zhou, M. I. Gomis, E. Lonnoy, T. Maycock, M. Tignor, T. Waterfield (eds.)]. World Meteorological Organization, Geneva, Switzerland, 32 pp. URL: https://www.ipcc.ch/sr15/chapter/summary-for-policy-makers/

Schellnhuber, HJ (2015). Selbstverbrennung (p. 453). Bertelsmann.

2.6 Question 6 – Future temperature increase

Q6What global mean surface temperature increase [in ° Celsius relative to the pre-industrial age, here: average from 1850 to 1900] is expected until 2100 under current policies?
Note: The estimated value is the median (50% quantile, ie with 50% lower values). The lower limit is the 16.0% quantile and the upper limit the 82.5% quantile, resulting in an approximate 67% confidence interval.
A) 1.5° Celsius [Range: 0.5, 2.5]
B) 2.1° Celsius [Range: 0.9. 3.3]
C) 3.3° Celsius [Range: 2.5, 4.4] (correct)
D) 5.2° Celsius [Range: 4.1, 6.3]
ReferencesClimateActionTracker (2018-12). WARMING PROJECTIONS GLOBAL UPDATE, Retrieved 2019-06-12, from https://climateactiontracker.org/publications/warming-projections-global-update-dec-2018/

Mastrandrea, M.D. et al (2010-06-07). Guidance Note for Lead Authors of the IPCC Fifth Assessment Report on Consistent Treatment of Uncertainties. https://wg1.ipcc.ch/SR/documents/ar5_uncertainty-guidance-note.pdf

Geiges, A. (2019-07-09). Re: Warming Projections Global Update, Dec 2018: Statistics [Personal Communication via Email].

2.7 Question 7 – Effect on human population

Q7What is the maximum number of humans, who can live on "Hothouse Earth" (ie the Earth after global warming > 4° Celsius)?
Note: Today’s population is 7.6 billion.
A) 12 billion people (12 000 000 000)
B) 8 billion people (8 000 000 000)
C) 4 billion people (4 000 000 000)
D) 1 billion people (1 000 000 000) (correct)
ReferencesSchellnhuber, HJ (2015). Selbstverbrennung. Bertelsmann, p. 507.

Steffen, W. (2019-03-16). Climate Change 2019: Rising Risks; Growing Challenges. Uppsala University, Retrieved 2019-05-21 from https://bit.ly/2Isb0Ue .

Rees, W. E. (2019-09-18). Yes, the Climate Crisis May Wipe out Six Billion People. The Tyee Online Magazine. URL: https://thetyee.ca/Analysis/2019/09/18/Climate-Crisis-Wipe-Out/

NEP Global Environmental Alert Service (GEAS) (2012). One Planet, How Many People? A Review of Earth’s Carrying Capacity - A discussion paper for the year of RIO+20. URL: https://na.unep.net/geas/archive/pdfs/geas_jun_12_carrying_capacity.pdf

McKinsey Global Institute (January 2020). Climate risk and response - physical hazards and socioeconomic impacts. ("Livability and workability", p. 98), https://mck.co/2ZuSYcV

2.8 Question 8 –  Average carbon dioxide emissions per person per year

Q8What is the average amount of carbon dioxide emissions [in tons of carbon dioxide equivalents, tons CO2e, per person per year] in Sweden (as of 2016)?
Note: Sweden can be regarded as an example of a highly-industrialized, European country.
A) 1.0 tons CO2e
B) 2.3 tons CO2e
C) 10.1 tons CO2e (correct)
D) 20.4 tons CO2e
ReferencesNaturvardsverket (2018-11-28) . Konsumtionsbaserade växthusgasutsläpp per person och år. URL: https://www.naturvardsverket.se/Sa-mar-miljon/Statistik-A-O/Vaxthusgaser-konsumtionsbaserade-utslapp-per-person/

2.9 Question 9 – Sustainable carbon dioxide emissions per person per year

Q9What is the sustainable carbon dioxide budget [in tons of carbon dioxide equivalents, tons CO2e, per person per year] to limit global warming to a "controllable" zone of up to 2° Celsius?
Note: Assuming global net zero carbon emissions till 2050 with an average human population of 8.2 billion individuals and peak carbon emissions in 2015.
A) 0.5 tons CO2e
B) 2.3 tons CO2e (correct)
C) 10.1 tons CO2e
D) 20.4 tons CO2e
ReferencesAtmosfair (2019-05-21) The Annual Climate Budget. Retrieved 2019-05-21, from https://www.atmosfair.de/en/green_travel/annual_climate_budget/ based on German Advisory Council on Global Change (WBGU), 2009. Special Report. URL: https://www.wbgu.de/en/publications/publication/solving-the-climate-dilemma-the-budget-approach

2.10 Question 10 – Emission of greenhouse gases by diet

Q10How much does the emission of greenhouse gases [in percent per person per year] change by following a vegetarian diet in comparison to a current average Western diet?
Note: A vegetarian diet does not contain any animal meat. The median change of greenhouse gas emissions is reported here in reference to average Western population-level food intakes (and corresponding greenhouse gas emissions).
A) +45%
B) +31%
C) 0 %
D) -31% (correct)
E) -45%
ReferencesAleksandrowicz, L., Green, R., Joy, E. J., Smith, P., & Haines, A. (2016). The Impacts of Dietary Change on Greenhouse Gas Emissions, Land Use, Water Use, and Health: A Systematic Review. PloS one, 11(11), e0165797. doi:10.1371/journal.pone.0165797

Wynes, S., & Nicholas, K. A. (2017). The climate mitigation gap: education and government recommendations miss the most effective individual actions. Environmental Research Letters, 12(7), 074024. https://doi.org/10.1088/1748-9326/aa7541

2.11 Question 11 – Emission of greenhouse gases by air travel

Q11How much carbon dioxide emissions [in tons of carbon dioxide equivalents, tons CO2e] does a flight London-New York-London correspond to?
A) 11.7 tons CO2e
B) 6.2 tons C02e
C) 3.4 tons CO2e (correct)
D) 0.1 tons CO2e
ReferenceAtmosfair (2019-05-21). Calculate Flight Emissions. Retrieved 2019-05-21, from https://www.atmosfair.de/en/offset/flight

2.12  Question 12 – Past action on carbon dioxide emissions

Q12How have global carbon emissions per year changed from 1996 (COP1) to 2014 (COP20) [in percent]?
Note: The Conference of the Parties (COP) within the United Nations Framework Convention on Climate Change (UNFCCC) is the most important international conference and political forum on climate change and takes place once per year.
A) -53%
B) -23%
C) 0%
D) +23%
E) +53% (correct)
ReferenceWorld Bank (2019-06-17). Data, CO2 emissions (kt) [EXCEL file]. Retrieved 2019-06-17 from https://data.worldbank.org/indicator/EN.ATM.CO2E.KT

2.13  Question 13 –  Required action on carbon dioxide emissions

Q13How much do global carbon emissions have to decrease [in percent] from levels in year 2010 until year 2030 to limit global warming to a "safe" global mean temperature increase of 1.5° Celsius until year 2100?
A) 0%
B) -15%
C) -45% (correct)
D) -100%
ReferencesIPCC, 2018: Global warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty [In Press]. Retrieved 2019-06-23 from https://www.ipcc.ch/sr15/. Details on citation: Chapter 2, p. 95

Andrews, R. (2019-04-23) . It's getting harder and harder to limit ourselves to 2°C [Website]. Retrieved 2019-06-23 from http://folk.uio.no/roberan/t/global_mitigation_curves.shtml.

3. Epilogue

Thank you for your participation!

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