Name OKADA Akira
Official Title Associate Professor
Affiliation Faculty of Environmental Studies
Profile Economic development and population growth have led to an increase in the use of transportation services. This, in turn, has led to an increase in environmental problems caused by transportation. The environmental problems caused by transportation include CO2 emissions that cause global warming, air pollutants, noise, and vibrations, and so on. The cost of environmental impacts to societies is said to amount to 4-5 percent of a country's GDP in monetary terms. Then, it is desirable for governments to control and reduce these environmental problems caused by transportation.
The main policies used to reduce and control environmental problems caused by transportation are technological regulations. However, there are many cases where technological improvements are approaching their limits. This means that technological regulations alone cannot sufficiently reduce environmental impacts from transportation. Therefore, market-based measures are gradually being introduced to curb transportation-related environmental problems by providing incentives to change people's behavior to reduce the environmental impacts. On the other hand, there is still a lack of knowledge about the effects of market-based measures, except for some transportation modes and policies.
Therefore, the main research conducted is to evaluate the effectiveness and evaluation of market-based measures to reduce environmental problems induced by the use of transportation by numerical simulations. The transportation modes targeted are automobile transportation and international shipping. We have carried out a computer simulation on road pricing policy, a numerical simulation of partial equilibrium analysis on transactions of fuel efficiency figures, and numerical simulation on an Emission Control Area. We have also studied the environmental problems from theoretical and empirical perspectives. In the former, we analyze the behavior of shipping companies in the international shipping market from a dynamic perspective. As for the latter, we are conducting empirical analysis on the effects of environmental impacts caused by automobile transportation due to changes in population composition.
Research Field(Keyword & Summary)
  1. (1) Evaluation of policies to mitigate environmental impact from International Maritime Transport

    With the growth of the world economy, the use of international transportation (international shipping and international air transport) has been increasing. The international community can no longer ignore the environmental problems caused by international transportation. Then, international organizations have been considering and implementing policies that employ economic incentives to deal with the environmental problems. However, many of the effects and problems of using economic incentive policies have not been studied in detail. Therefore, I will quantitatively analyze and evaluate the environmental policies that are being planned and implemented in international transportation, mainly international shipping.

  2. (2) Relationship between environmental impact and transportation

    Since the beginning of 2000, CO2 emission per capita from transportation in some developed countries, such as Japan and Germany, have started to decrease. Keeping in mind the IPAT model proposed by Ehrlich and Holden, the environmental impact from transportation is related to population, especially the composition of the population. In particular, the environmental impact of transportation is expected to be related to the aging rate of the population. Therefore, this study uses empirical analysis to examine the relationship between composition of population and the environmental impact from transportation.

Representative Papers
  1. Kazusei Kato, Toshiyuki Uemura, Yuichi Indo, Akira Okada, Katsumi Tanabe, Shinichi Saito, Hitoshi Oguma, Hirotaka Yamauchi, Eiji Shiomi, Madoka Saegusa, Kazuyoshi Migita (2011) Current accounts of Japanese airports, Journal of Air Transport Management 17 (2), 88-93.
  2. A Okada (2012) Is an increased elderly population related to decreased CO2 emissions from road transportation? Energy Policy 45, 286-292.
  3. H Tanaka, A Okada (2019) Effects of market-based measures on a shipping company: Using an optimal control approach for long-term modeling, Research in Transportation Economics 73, 63-71.
  4. A Okada (2019) Benefit, cost, and size of an emission control area: a simulation approach for spatial relationships, Maritime Policy & Management 46 (5), 565-584.
Grant-in-Aid for Scientific Research Support: Japan Society for Promotion of Science (JSPS)
Recruitment of research assistant(s) No
Affiliated academic society (Membership type) (1) Japan Society of Transportation Economics (Member)
Education Field (Undergraduate level) Microeconomics, Public Economics and Public Policy, Elementaly Statistics
Education Field (Graduate level) Transportation Economics, Environmental Economics, Econometrics