Another misconception around "Sustainable Aviation" is that existing carbon offset schemes will be effective at reducing emissions.
International aviation and shipping are the only two sectors that aren't included in the national emissions reduction targets, submitted by states under the Paris Agreement. Instead, in 2016 the industry came up with something called the "Carbon Offsetting and Reduction Scheme for International Aviation” (CORSIA) which apparently enables ‘carbon neutral growth’ from 2020, through the use of offset credits [1]
The idea is that airlines will have to buy credits when they emit carbon, and those credits will then go towards reducing carbon elsewhere. Essentially: I don't want to reduce my emissions, so I'll pay somebody else who promises to emit less...
However, the CORSIA scheme has numerous weaknesses [2]:
• it’s voluntary from 2020, and only becomes mandatory after 2027
• the scheme isn’t legally binding: there are no enforcement mechanisms to ensure compliance
• it only applies to CO2 and ignores non-CO2 emissions, despite their large climate impact [3]
• it only applies to emissions in excess of 2019 levels, so for the considerable future, the majority of carbon emissions will not be offset [4]
• CO2 emissions are offset using types of schemes which have so far proven very ineffective [5]
• the offset credits are simply far too cheap per tonne of CO2. For example, they will cost far less than $10 per tonne of CO2. As a comparison, industrial CO2 capture is currently closer to $1000 per tonne [6] and is projected to (best case) reduce to $100 per tonne over the next few decades [7]. This doesn't even include the costs of then storing the carbon, after it’s captured.
The key takeaway messages are:
• the CORSIA terms are too weak
• the majority of emissions (pre-2019 levels of CO2 and all non-CO2) won’t be offset
• for the emissions that are offset, the offset credits are FAR too cheap
References:
1. ICAO, Environmental Report, 2019: “Chapter 6: Climate Change Mitigation: CORSIA”. See: [ Ссылка ]
2. Transport & Environment, September 2019: “Why ICAO and CORSIA cannot deliver on climate: A threat to Europe’s climate ambition”. See: [ Ссылка ]
3. D.S. Lee et al., Atmospheric Environment, September 2020: “The contribution of global aviation to anthropogenic climate forcing for 2000 to 2018”. See: [ Ссылка ]
4. International Council on Clean Transportation (ICCT), February 2017: “Policy Update: International Civil Aviation Organization’s Carbon Offset and Reduction Scheme for International Aviation (CORSIA)”. See: [ Ссылка ]
5. Öko-Institut, March 2016: “How additional is the Clean Development Mechanism?”. See: [ Ссылка ]
[Page 11: an analysis of similar EU offset schemes found that up to 85% of the projects covered had a low likelihood that emission reductions were additional (would not have occurred anyway) and not-overestimated.]
6. Climeworks, 2020: “Enable removal of CO₂ from the air”. See: [ Ссылка ]
7. D.W. Keith et al (Carbon Engineering), Joule, June 2018: “A Process for Capturing CO2 from the Atmosphere”. See: [ Ссылка ]
