Approaches for separating domestic and international aviation emissions Odette Deuber Technical workshop on emissions from aviation and maritime transport.

Approaches for separating domestic and international aviation emissions

Odette Deuber

Technical workshop on emissions

from aviation and maritime transport

Oslo, 4.-5. October 2007

Overview

Background

Reporting guidelines

Methods applied in Annex I Countries

Use of databases on PKM and TKM

Conclusions

Background

Bunker fuel do not fall under binding targets of the Kyoto Protocol, thus necessity of splitting fuel consumption by aviation into dom. and int. shares.

Reporting guidelines for and definitions of emissions from domestic and international aviation:

IPCC Guidelines, Good Practice Guidance.

Methods for separating activity data for dom. and int. aviation are country-specific.

Methodologies and assumptions must be described in detail in the National Inventory Reports.

Good Practice Guidance 2000 → 2006:

Tier 1: Fuel based approach

Tier 2: Based on fuel use and number of LTO cycles

a) aggregated level of all aircrafts

b) level of individual aircrafts - preferably

Tier 3: Methods using flight movement data

3 A: based on origin and destination data

3 B: based on full trajectory flight

DOM INT

Departure and arrival in the same country yes no

Departure from one country and arrival in another No yes

Criteria for Defining International or Domestic Aviation

Assessment of National Inventory Reports 2007

Tier 1: Bulgaria, Belarus, Canada (modified), Croatia, Czech Republic, Estonia, Germany, Greece, Hungary, Iceland, Lithuania, Latvia, Luxembourg, New Zealand, Poland, Romania, Russian Federation, Slovakia, Slovenia, Turkey, Ukraine, USA

Tier 2: Australia, Belgium, Ireland, Italy (a), Japan, Netherlands, Norway, Portugal (a), Spain, Sweden (a)

Tier 3: Austria, Denmark, Finland, France, Switzerland, United Kingdom

Top Down Approaches

Energy Statistics

Estonia, (Ireland), Poland, Austria

Taxation/custom authorities, Fuel expenditures

Australia (int), Japan (int), USA (foreign flagged)

Fuel suppliers/Fuel sales

Iceland, New Zealand, Finland (int), Spain

Bottom-up Approaches/ Models

Survey of airline companies, aircraft movement data, statistical offices or statistics from transport ministries, Airport records

Norway, France (dom), USA (US flag carrier),

Italy (LTO), Portugal,

Sweden, Netherlands (precursor), Belgium, Ireland

Austria (until 2000 MEET, since 2001 dom./int. LTO),

Denmark, United Kingdom, Switzerland (FOCA), Finland (ILMI)

Data on tonne-km

Canada (dom airlines dom-int)

Other origin- destination data, Air carrier schedules, Air traffic control records, full trajectory models

ANCAT3, Official Airline Guide (Future Aviation Scenario Tool FAST), SAGE, Aviation Emission Model (AEM)

Other Approaches

Expert Judgement

Bulgaria (20%/80%); Romania (20%/80%); Ukraine (country comparison 6%/94%)

Research Projects

Germany (20%/80%), Latvia (dom. emissions), Netherlands (dom. CO2)

“Small country approach“: gasoline = dom, jet fuel = int.

Lithuania, Belgium, Slovenia, Hungary

Summary

A variety of methods are applied to separate dom. from int. aviation emissions.

Often different approaches are combined, usually bottom up calculations are adjusted to energy statistics.

In less developed approaches it is difficult to map variations in the split over time.

If energy statistics provide a reliable split, acceptable results can be obtained without higher tiers (bottom-up approaches).

Countries with Tier 2 and 3 usually have more detailed data on the split of dom – int LTO cycles.

Countries with Tier 3 use generally detailed air movement data for the spilt.

Comparison of model results and national approaches is worthwile.

Separating emissions from dom. and int. aviation on the basis of TKM Statistics?

Could statistics on Freight- and Passenger-KM be usedto check consistency of splits calculated (dom-int) on the basis of other approaches? as proxy for fuel consumption?

ICAO Database: dom. and int. passenger and freight transport data

(PKMdom, PKMint, TKMdom, TKMint)Complete time series 1990 – 2004 For rough estimates used here: 1990, 1995, 2000, 2003Flag-based data – fuel sale data

Method to check the applied split between domestic and international aviation emission

PKM TKM

TKM totalCO2

Assumption:1 PKM = 0,15 TKM

Flag-based -> Fuel sale data

Dom. Emissions: share of dom. TKM flown by domestic/foreign flag based carriers

Int. Emissions: share of int. TKM by all carriers arriving/departing in one country and share of domestically purchased fuel for these flights

CO2/TKMtotal

UNFCCC ICAO

CO2 intensity depends on:

Distances of flightsAircraft fleet: age and compositionEmission reductions measures

CO2 Intensities of domestic aviation emissions: Annex I Countries - Outlier

0

20

40

60

80

100

120

140

160

180

1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003

kg CO2/TKM

Czech Republic

Bulgaria

Ireland

CO2 Intensities in dom. Aviation (Annex I Countries)

Tier 2 Countries

0

1

2

3

4

5

6

1990 1995 2000 2003

kg CO2/PKM

Tier 3 Countries

0

1

2

3

4

5

6

1990 1995 2000 2003

Kg CO2/TKM

Tier 1 Countries

0

1

2

3

4

5

6

1990 1995 2000 2003

kg CO2/TKM

CO2 Intensities in int. Aviation (Annex I Countries)

Tier 2 Countries

0

1

2

3

4

5

6

1990 1995 2000 2003

kg CO2/PKM

Tier 3 Countries

0

1

2

3

4

5

6

1990 1995 2000 2003

Kg CO2/TKM

Tier 1 Countries

0

1

2

3

4

5

6

1990 1995 2000 2003

kg CO2/TKM

0

1

2

3

4

5

6

1990 1995 2000 2003

kg CO2/TKM

CO2 Intensities of selected countries

Austria dom T3

Denmark dom T3

Greece dom T1Lufthansa fleet average (2006): 0,5 kg CO2/TKM

regional flights (2006): 1 kg CO2/TKM

CO2 Intensities of selected countries

0

1

2

3

4

5

6

1990 1995 2000 2003

kg CO2/TKM

Austria dom

Austria int

Denmark int

Denmark dom

Greece dom

Greece int

Lufthansa fleet average (2006): 0,5 kg CO2/TKMregional flights (2006): 1 kg CO2/TKM

CO2 Intensities in Aviation (Tier 3)

Tier 3 Countries

0

1

2

3

4

5

6

1990 1995 2000 2003

Kg CO2/TKM

Denmark

Tier 3 Countries

0

1

2

3

4

5

6

1990 1995 2000 2003

Kg CO2/TKM

international domestic

DenmarkAustriaAustria

Method to estimate emissions?

PKM TKM

TKMtotal CO2/TKM

Assumption:1 PKM = 0,15 TKM

CO2

ICAOData on CO2 intensity available for domestic oder international flights?

Default CO2 intensity cannot be given as there are a variety of influencing factors.

Case Study: Canada‘s method to split fuel sold to dom. carriers into dom. and int. activity

Fuel sold to national carriers TKMdom

Fueldom

Flag → Fuel-based approachAssumption: share of int. TKM which are flown by domestically purchased fuel (69%/31%)

Fuelint CO2int

TKMint

Split: dom – int

Fuel sold to foreign carriers

In excellent agreement with SAGE and AERO2K

Conclusions

Using TKM statistics can be worthwhile for checking the split of dom. and int. aviation emissions

If dom. and int. CO2 intensities fluctuate strongly from year to year and fluctuate in opposite signs -> check split.

Final conclusion on CO2 intensities only on the basis of complete time series and country details.

Level of CO2 intensity compared with other countries might give a hint on quality of separation method.

TKM is not per se a proxy for fuel consumption.Conversion of flag-based into fuel sale-based data usually easier

for domestic aviation.There are cases in which also int. aviation emissions can be

obtained by this approach.

Very Last Conclusion…

Let us be creative to find further methods for

separating domestic and international emissions!