Aviation

• Author: Aoife O'Leary
• Pages: 424-443

Page 424 Legal Pathways to Deep Decarbonization in the United States

I. Introduction

Domestic aviation emissions in the United States are

responsible for 3% of total U.S. greenhouse gas (GHG)

emissions1 and 18% of all worldwide aviation GHG emis-

sions.2 Total U.S. aviation emissions (domestic and interna-

tional) equate to 29% of all worldwide aviation emissions.3

International aviation emissions are growing rapidly and

are projected to grow by 300% by 2050 if no action is

taken.4 All the Deep Decarbonization Pathways Project

(DDPP) scenarios show that U.S. domestic aviation energy

use will decline by approximately two-thirds by 2050 due

Author's Note: is chapter represents the personal views of the author and does not

necessarily reect the ocial policy or position of any organization she is aliated with.

1. U.S. E P A, I  U.S. G-

 G E  S: 1990-2014, at 3-18, 3-86 (2016) (EPA

430-R-16-002) [hereinafter U.S. GHG I].

2. Id.

3. Id.

4. E S, I C A O,

G A CO2 E P  2050 (2010) (GIACC/4

IP/1) [hereinafter G A CO2 E P  2050].

to aggressive energy eciency improvements and the use

of biofuels.5 (DDPP projects roughly three exajoules6 of

energy demand from aviation in 2050 in the reference

scenario, compared to one exajoule in all four reduction

pathways.7) International aviation is not mentioned in the

report at all. In July 2016, the U.S. Environmental Pro-

tection Agency (EPA) determined that aviation emissions

cause or contribute to climate-changing air pollution in

ways that may reasonably be expected to endanger human

5. e aviation industry generally refers to “alternative fuels” rather than

biofuels, but for the purposes of consistency throughout this book, this

chapter will use the term biofuels. Alternative fuels are fuels made from

nonpetroleum sources and include biofuels. Indeed, most alternative fuels

are biofuels; see I A T A, IATA 2015

R  A F (10th ed. 2015), available at http://www.

iata.org/publications/Documents/2015-report-alternative-fuels.pdf.

6. An exajoule is one billion billion joules (a fundamental energy unit).

7. J H. W  ., P  D D  

U S, U.S. 2050 R, V 1: T R 31 (Deep

Decarbonization Pathways Project & Energy and Environmental Economics,

Inc., 2015), available at http://usddpp.org/downloads/2014-technical-report.

pdf [hereinafter DDPP T R].

Chapter 16

Aviation

by Aoife O’Leary

Summary

Aviation is the most carbon-intensive form of travel and is a signicant contributor to climate change. Inter-

national aviation emissions are growing rapidly and are projected to grow 300% by 2050 if no action is taken.

A 2016 report has shown that, in order for international aviation to only consume 12% of the carbon budget

that would allow the world to stay within a 1.5°C temperature increase by 2050, the absolute maximum of

innovation, operational improvements, and biofuels must be deployed. An ambitious policy to reduce aviation

emissions is urgently needed. e United States has not enacted any emissions reduction measures for aviation.

ere are no substantive legal barriers to the United States doing so, but there are signicant political challenges,

including strong opposition from the aviation industry and dierences of views among the agencies that regulate

aviation in the United States, especially the U.S. Environmental Protection Agency and the Federal Aviation

Administration. e International Civil Aviation Organization has been discussing the regulation of aviation

emissions for two decades. And within the industry itself, there are a number of eciency goals and some airlines

are beginning to test biofuels. However, the sum of all these eorts will be inadequate to reduce aviation emis-

sions by two-thirds by 2050, as is envisaged in the Deep Decarbonization Pathways Project reports. is chapter

sets forth a variety of measures that, when combined, could put the United States on track to reduce aviation

emissions by two-thirds by 2050.

Page 425

health a nd welfare8 but has proposed no measures to miti-

gate or reduce emissions to date. e International Civil

Aviation Organization (ICAO) has agreed on a carbon

dioxide (CO2) sta ndard9 and osetting scheme for avia-

tion emissions called the Carbon Osetting and Reduc-

tion Scheme for International Aviation (CORSIA).10 ese

measures aim for carbon-neutral growth in aviation emis-

sions from 2020 (i.e., emissions growth above 2020 levels

would be oset against emissions reductions in other sec-

tors). To ensure emissions decrease in line with the DDPP

reduction goal of two-thirds by 2050, further action will

be required by the United States and ICAO.

Section II of this chapter will rst look at the status

of aviation emissions regulation in the United States and

internationally, outlining the measures already agreed.

Section III will then consider the feasibility of reduc-

ing emissions by considering what options are available

to reduce emissions, including biofuels and operational

measures. Section IV will then look at the legal options

that could be used to ensure these reduct ions are achieved

at both domestic and international levels. Section V will

identify some co-benets that should be maximized as

measures are introduced to reduce emissions, and Section

VI will conclude.

While part of this chapter is a consideration of reduc-

tion of emissions at airports, this chapter will not discuss

transport to or from the airport or how to reduce emissions

from the airport buildings themselves, as these topics are

discussed elsewhere in the book.11 However, it is impor-

tant to note here that investments in public transport or

highways that reduce travel time or costs to ge t to airports,

while potentially reducing vehicle trac, could have the

adverse eect of encouraging people to y more.

roughout this chapter, where recommendations are

made or measures are detailed, the amount of potential

emissions reductions is stated if possible. If the amount

of potential reductions is not stated, it is because there

8. Finding at Greenhouse Gas Emissions From Aircraft Cause or Contribute

to Air Pollution at May Reasonably Be Anticipated to Endanger Public

Health and Welfare, 81 Fed. Reg. 54421, 54422 (Aug. 15, 2016) [hereinafter

Endangerment Finding].

9. Press Release, ICAO, ICAO Council Adopts New CO2 Emissions Standard

for Aircraft (Mar. 6, 2017), https://www.icao.int/Newsroom/Pages/ICAO-

Council-adopts-new-CO2-emissions-standard-for-aircraft.aspx [hereinafter

ICAO CO2 Standard].

10. ICAO, Carbon Osetting and Reduction Scheme for International Aviation

(CORSIA), http://www.icao.int/environmental-protection/Pages/market-

based-measures.aspx (last visited Feb. 1, 2018).

11. See Part III, Energy Eciency, Conservation, and Fuel Switching in Build-

ings and Industry, and Part IV, Energy Eciency, Conservation, and Fuel

Switching in Transportation, of this book for more on this.

appears to be no publicly available information on the

actual or possible reductions to be achieved.

II. Status of Regulation of GHGs From

Aviation

Aviation emissions are a signicant contributor to climate

change. is section will set out how U.S. aviation emis-

sions have grown (or decreased) between 1990 and 2014,

and what gases cause the warming eect of aviation. is

section will then set out the history of aviation regulation

in the United States and internationally, and look at the

feasibility of emissions reductions (what technologies or

methods exist that c an reduce aviation emissions). e sec-

tion will conclude with a look at reduction objectives in

the DDPP and also whether similar reduction goals have

been set in the United States or internationally.

A. U.S. Aviation Emissions Are a Signif‌icant

Contributor to Climate Change

Aviation is by no means insignicant in the context of

overall U.S. emissions. U.S. domestic aviation is currently

responsible for not only 3% of total U.S. emissions but

also 11% of emissions in the transport sector.12 Domes-

tic aviation compromises all ights that both take o and

land in the United States and includes commercial, mili-

tary, and recreational aviation, along with small aircraft.

e 29% of worldwide aviation emissions caused by U.S.

aviation (U.S. domestic and international ights depart-

ing the United States) represents 0.5% of all emissions

worldwide.13 (U.S. international aviation emissions are

measured (per the Intergovernmental Panel on Climate

Change (IPCC) guidelines14) based on fuel purchased in

the United States for ights departing to another coun-

try.) U.S. domestic aviation emissions alone are responsible

for 18% of all aviation emissions worldwide.15 Aviation’s

emissions are projected to increase by 300% by 2050 if

no action is taken.16 e Federal Aviation Administration

(FAA, a unit of the U.S. Department of Transportation)

projects that U.S. aviation fuel consumption (domestic

and international) will grow by 49% from 2010 to 2035,

12. O  T  A Q, EPA, EPA T F

S  A GHG E F A E 2 (2015)

(EPA-420-F-15-023).

13. Id.

14. C D W  ., IPCC, 2006 IPCC G 

N G G I 3.56 (2006).

15. Id.

16. G A CO2 E P  2050, supra note 4.