Which of the following sectors contributed least to the global carbon dioxide…
2020
Which of the following sectors contributed least to the global carbon dioxide emissions in the year 2014 as per IPCC report?
- A.
Transportation
- B.
Agriculture and forest land use
- C.
Industry
- D.
Utility (Electricity and Heat Production)
Show answer & explanation
Correct answer: A
Concept
The IPCC Fifth Assessment Report (AR5) was released in 2014; the sectoral emission shares it presents are for the reference year 2010, so a question phrased "in the year 2014 as per the IPCC report" is asking about these AR5 figures. AR5 (Working Group III) splits total global greenhouse-gas emissions by economic sector. The standard ranking of direct-emission shares is: electricity and heat production largest, then agriculture/forestry and other land use (AFOLU), then industry, then transport, with buildings smallest. To identify the sector that contributes the LEAST among given options, compare their reported shares and choose the smallest. A note on the data: the AR5 Figure SPM.2 shares are of total anthropogenic greenhouse-gas emissions expressed as carbon-dioxide equivalent, not CO2 alone — this is the standard chart such questions are built on, and the stem's phrase "carbon dioxide emissions" is read as referring to it. On that AR5 GHG chart, Transportation's roughly 14% share is the smallest of the four sectors offered here. (A strict CO2-only accounting would shift some shares — AFOLU, for instance, carries a large non-CO2 fraction of methane and nitrous oxide — so the intended answer follows the standard AR5 GHG breakdown rather than a CO2-only recomputation.)
Application
The AR5 (Figure SPM.2) direct-emission shares for the four sectors offered are:
Sector | Approx. share of global GHG (AR5, 2010 data) |
|---|---|
Electricity and heat production | about 25% (largest) |
Agriculture and forest land use (AFOLU) | about 24% |
Industry | about 21% |
Transportation | about 14% |
Transportation, at roughly 14%, is the smallest of these four shares, so its share of global carbon-dioxide / greenhouse-gas emissions is the lowest among the sectors listed.
Contrast
Electricity and heat production (about 25%) is the largest emitter because most power is still generated by burning coal, gas and oil.
Agriculture and forest land use (about 24%) is the second-highest share, driven by livestock, fertiliser use, rice cultivation and deforestation.
Industry (about 21%) is the third-highest, owing to fuel combustion and process emissions in manufacturing such as cement and steel.
Transportation (about 14%) lies below all three of the above shares.
Result
On the AR5 figures, Transportation (about 14%) holds the lowest share of global emissions of the four sectors listed.