This document discusses transport and mobility theory. It defines key concepts like transport vs mobility, multimodality vs intermodality, and altermobilities. It also covers transport-related models and observations, including Kaya identity, Zahavi's conjecture, rebound effect, induced traffic, and externalities. Additionally, it addresses the relationship between transport, energy use, emissions and economic growth as well as inequality and other societal factors. The document emphasizes that reducing both passenger and freight transport is needed to significantly decrease emissions and that efficiency alone is insufficient without also decreasing travel activity and encouraging more sustainable modes.

1. Transport and Mobility
Fact or Fiction – Part 2
Emilia Suomalainen
emilia.suomalainen@gmail.com
Cette photo par Auteur inconnu est soumise à la licence CC BY-SA-NC

2. Contents
A brief history of transport and mobility
Transport facts: mode share and emissions
The case of cars
Theory: transport and mobility
Transport and inequality
Economy, energy and transport
The big picture

3. Transport – A Bit of
Theory
A few key concepts

4. Transport vs. Mobility
Transport: focus on the transport system
Point of view of the operator, planning authority, city, municipality
Engineering, traffic planning, infrastructure, road construction, vehicles, routes,
network, …
Mobility: focus on the service
Point of view of the user
User needs and access to services (jobs, schools, shopping, recreation, health
services, culture, …)
User-friendliness, integration, digital tools, MAAS, …

5. Multi- vs. Intermodality
Multimodality: use of several
different means of transport on a
regular basis
Intermodality: combination of
several different means of
transport during the same journey
http://geoconfluences.ens-lyon.fr/informations-scientifiques/a-la-une/notion-a-la-une/notion-a-la-une-intermodalite

6. Altermobilities
Alternative modes of transport
Especially alternatives to private car and to motorised modes
Soft modes, non-motorised modes, sustainable mobility, active travel
Also so-called “new mobilities”
Beware of environmental impacts, see eg. https://www.itf-oecd.org/good-to-go-
environmental-performance-new-mobility
Cf. https://en.forumviesmobiles.org/marks/altermobilities-449

7. Kaya Identity
The “Kaya Identity” or decomposition analysis of emissions:
CO2 = population * GDP/population * energy/GDP * CO2/energy
Applied to transport emissions:
This same idea is sometimes presented (eg. IEA, Lee Schipper) as:
Emissions = Activity * Structure * Intensity * Fuel = ASIF

8. Hierarchy: Avoid – Shift – Improve
https://www.researchgate.net/publication/330079325_Transport_and_Climate_Change_2018_-_Global_Status_Report/figures

9. Zahavi’s Conjecture
Observation from the 1970s
Yacov Zahavi, http://www.surveyarchive.org/zahavi.html
The travel time budget of everyday mobility stays (approximately) constant
Consequence: faster transport systems => people travel further

10. Zahavi’s Conjecture Evolution since 1800s
in France
Aurélien Bigo 2020, http://www.chair-energy-prosperity.org/publications/travail-de-these-decarboner-transports-dici-2050/

11. Rebound Effect
“Jevons Paradox”: technological progress increases resource use efficiency – the
consumption of the resource rises due to increasing demand
Stanley Jevons, 1865: “The Coal Question”
Solution: efficiency gains paired with
government intervention that reduces
demand (eg. fuel tax)?

12. Induced Traffic
Paradox: increasing roadway capacity does not reduce congestion in the long run =>
induced traffic
Effect recognised since the 1930s
The opposite also exists: disappearing traffic or traffic evaporation

13. Externalities
An externality is the cost or benefit that is imposed on a third party who did not agree
to incur that cost or benefit
Concept developed by Arthur Pigou in the 1920s
There are many negative externalities related to transport: air pollution, GHG
emissions, congestion, noise, road accidents, …
Also positive externalities (notably for active mobility)

14. Transport is a Derived Demand
Transport allows people to access services, activities and opportunities
Transport is seldom a finality in itself, but rather a means to an end
But: Zahavi’s conjecture (constant travel time budget) and rebound effects
Chosen vs. constrained mobility
Eg. holiday or week-end trips vs. commuting
Choice of mode of transport depends on cost but also travel time, convenience,
perceived safety, …

15. Mobility and Our Lifestyles
Transport demand is closely linked to our lifestyles
Developed vs. developing country
Category of population: active, inactive, student, retiree; age, gender, income, family
size, …
Urban, suburban, rural environment
Urban density (North America vs. Europe vs. Asia)
Available public transport
Car ownership depends on all the above

16. Urban Density vs. Emissions
https://www.climate-chance.org/comprendre-observatoire/bilan-mondial-de-laction-climat-par-secteur-2020/

17. Vehicle Ownership – Example
https://www.researchgate.net/publication/46523642_Vehicle_Ownership_and_Income_Growth_Worldwide_1960-2030/figures

18. Vehicle Ownership – Example
https://www.researchgate.net/publication/46523642_Vehicle_Ownership_and_Income_Growth_Worldwide_1960-2030/figures

19. Transport Demand Elasticities
Transport demand fairly inelastic to fuel price in the short run
A large number of constrained trips
More elastic in the long run
Buy a smaller, more fuel-efficient car, etc.
Elasticity of demand to fuel price also depends on the income level
NB: elasticities differ from country to country, one income class to another, they can
be asymmetrical, change in time, depend on the price level, etc.
Cf. https://trid.trb.org/view/1143570

20. Fuel Price Elasticities – Example
https://trid.trb.org/view/1143570

21. Fuel Price vs. Transport Energy Use
https://trid.trb.org/view/1143570

22. Travel Demand vs. GDP
Aurélien Bigo 2020, http://www.chair-energy-prosperity.org/publications/travail-de-these-decarboner-transports-dici-2050/

23. Transport and Inequality
Inequalities across and within countries

24. Transport and Inequality
Oswald et al. 2020, https://doi.org/10.1038/s41560-020-0579-8

25. Transport and Inequality
Ivanova and Wood 2020, https://doi.org/10.1017/sus.2020.12

26. The Case of Aviation
https://theicct.org/blog/staff/not-every-tonne-of-aviation-CO2

27. The Case of Aviation
https://theicct.org/blog/staff/should-you-be-ashamed-flying-probably-not

28. The Case of Aviation
Gössling and Humpe 2020, https://doi.org/10.1016/j.gloenvcha.2020.102194

29. Transport and Gender
Women often drive less => more car use as passenger, more public transport and walking
They also have less road accidents (less risky driving behaviours)
But are more likely to be injured
Women often have more complex travel patterns (multiple stops and trip purposes)
https://www.weforum.org/agenda/2020/03/urban-transport-mobility-women/
Safety concerns more important
Relatively few women are employed in the transport sector
22% in the EU, https://www.itf-oecd.org/itf-work-gender-transport
Access to transport important for equal opportunities

30. Transport and Age
Age has an impact on travel distances and modes
Young retirees travel more than before, often by car
Car ownership rises with age (linked to income)
Older seniors use less active travel
Adaptation of transport systems to the elderly key with aging populations
A challenge for not just motorised transport but also pedestrian infrastructure
Potential market for autonomous vehicles (AV)

31. Energy, Economy and
Transport
Linkages and decoupling

32. Questions to be answered:
What happens when countries get richer, is there a plateau of transport demand?
Has there been a decoupling of transport, its energy use and emissions?

33. Decarbonisation in Theory
http://www.chair-energy-prosperity.org/publications/scenarios-decarbonation-transports-2050/

34. Decarbonisation in Theory
http://www.chair-energy-prosperity.org/publications/scenarios-decarbonation-transports-2050/

35. Passenger Transport and GDP
https://www.eea.europa.eu/data-and-maps/daviz/trends-in-passenger-transport-demand-7#tab-chart_1

36. Freight Transport and GDP
https://www.eea.europa.eu/data-and-maps/daviz/freight-transport-volumes-and-gdp-7#tab-chart_4

37. Growth in Pax Transport vs. GDP
https://www.eea.europa.eu/data-and-maps/figures/correlation-in-growth-of-passenger-transport-vs-gdp-growth

38. Growth in Freight vs. GDP
https://www.eea.europa.eu/data-and-maps/figures/correlation-of-growth-of-freight-transport-vs-gdp-growth

39. PKT vs. GDP per Capita
https://twitter.com/Sonia_Yeh/status/1333537917973753864/photo/1

40. Not Just a Transport
Issue
The big picture

41. Oil Production vs. GDP
https://slides.pimoid.fr/jancovici/mines_2019/

42. Observed Decreases in CO2 Emissions
https://www.nature.com/articles/s41467-020-18922-7

43. Impacts of the Covid-19 Crisis
Liu et al. 2020, https://doi.org/10.1038/s41467-020-18922-7

44. Key Points
Road traffic is responsible for a lion’s share of emissions
Both pax and freight transport need to be decarbonised
Also many other negative externalities, notably air pollution
Efficiency improvements alone are not enough
Avoid – shift – improve hierarchy => need to decrease the number of trips and
encourage more sustainable transport modes
Historically only relative decoupling of energy use and emissions
Absolute decrease in emissions required

45. Thank you for your
attention!
Emilia Suomalainen
emilia.suomalainen@gmail.com
Cette photo par Auteur inconnu est soumise à la licence CC BY-NC-ND