and a shift to public transportation. As flood disaster prevention, it would be easiest
and most effective if people could retreat from flood-hazard areas. In addition, if
retreated people moved to the city center and located around train stations, GHG
emissions could also be reduced. In this case, climate change mitigation and
adaptation measures are compatible.
In fact, the automobile fuel consumption under land-use scenarios considering
flood disaster prevention and compact city design in local cities has been quantitatively evaluated (Taniguchi et al. 2005). Nagao et al. (2012) considered safety
against disasters as one of the quality of life (QOL) indexes, and selected retreat and
cohesion areas in a local city. However, the Tokyo Metropolitan Area, which is still
by far the largest megacity in the world, is extremely vulnerable against climate
risks, especially flood risk, because a large part of the assets is concentrating near
the bay area. On the other hand, researchers are projecting the increase of flood risks
in the Tokyo Metropolitan Area, due to climate change as well as tsunami from
future big earthquakes. We need to consider appropriate land uses that are more
resilient against climate risks in megacities (Yamagata et al. 2013).
As for the carbon dioxide (CO 2 ) emission reduction potentials for the land-use
scenarios, especially compact city, many studies have indicated that cities with low
residential density rely on automobile transportation. Therefore the reduction of CO 2
emissions caused by transportation use would be attained by changing the urban
layout to a more compact one, which would lead to the increase of the use of public
transportation and the reduction of trip length by car (e.g. Newman and Kenworthy
1999; Hayashi et al. 1995; Jenks et al. 1996; Naess 1996; Roo and Miller 2000;
Williams et al. 2000; Taniguchi et al. 2005, 2008; Nakamichi et al. 2007).
Also, it is necessary to estimate indirect emissions as well as direct emissions to
clarify the liability of daily energy consumption-based CO 2 emissions. Recently,
many studies have started considering also the indirect emissions (Abe et al. 2002;
Nakamura and Otoma 2004; Yamashita et al. 2007; Dhakal 2009; Kennedy
et al. 2010; Xi et al. 2011; Shigeto et al. 2012). Hence, in this paper, we also estimated
the indirect emissions by allocating the emissions to the regions where the energy was
consumed, using the data on the expenditure for households’ daily living items.
12.1.3 Technological Approach for Climate Change
Mitigation/Adaptation
In addition to the above mentioned mitigation measures with compact city scenarios, we also need to consider those with renewable energy use. Since the 2011 Great
East Japan Earthquake, the Japanese Government has gradually changed its energy
policies toward distributed renewable energy generation. As a part of such efforts,
the Japanese Diet has approved the “Act on the Purchase of Renewable Energy
Sourced Electricity by Electric Utilities (Act)”, which is a feed-in tariff regime for
renewable energy, effective from 1 July 2012. Under the Act, electric utility
244
K. Nakamichi et al.
and most effective if people could retreat from flood-hazard areas. In addition, if
retreated people moved to the city center and located around train stations, GHG
emissions could also be reduced. In this case, climate change mitigation and
adaptation measures are compatible.
In fact, the automobile fuel consumption under land-use scenarios considering
flood disaster prevention and compact city design in local cities has been quantitatively evaluated (Taniguchi et al. 2005). Nagao et al. (2012) considered safety
against disasters as one of the quality of life (QOL) indexes, and selected retreat and
cohesion areas in a local city. However, the Tokyo Metropolitan Area, which is still
by far the largest megacity in the world, is extremely vulnerable against climate
risks, especially flood risk, because a large part of the assets is concentrating near
the bay area. On the other hand, researchers are projecting the increase of flood risks
in the Tokyo Metropolitan Area, due to climate change as well as tsunami from
future big earthquakes. We need to consider appropriate land uses that are more
resilient against climate risks in megacities (Yamagata et al. 2013).
As for the carbon dioxide (CO 2 ) emission reduction potentials for the land-use
scenarios, especially compact city, many studies have indicated that cities with low
residential density rely on automobile transportation. Therefore the reduction of CO 2
emissions caused by transportation use would be attained by changing the urban
layout to a more compact one, which would lead to the increase of the use of public
transportation and the reduction of trip length by car (e.g. Newman and Kenworthy
1999; Hayashi et al. 1995; Jenks et al. 1996; Naess 1996; Roo and Miller 2000;
Williams et al. 2000; Taniguchi et al. 2005, 2008; Nakamichi et al. 2007).
Also, it is necessary to estimate indirect emissions as well as direct emissions to
clarify the liability of daily energy consumption-based CO 2 emissions. Recently,
many studies have started considering also the indirect emissions (Abe et al. 2002;
Nakamura and Otoma 2004; Yamashita et al. 2007; Dhakal 2009; Kennedy
et al. 2010; Xi et al. 2011; Shigeto et al. 2012). Hence, in this paper, we also estimated
the indirect emissions by allocating the emissions to the regions where the energy was
consumed, using the data on the expenditure for households’ daily living items.
12.1.3 Technological Approach for Climate Change
Mitigation/Adaptation
In addition to the above mentioned mitigation measures with compact city scenarios, we also need to consider those with renewable energy use. Since the 2011 Great
East Japan Earthquake, the Japanese Government has gradually changed its energy
policies toward distributed renewable energy generation. As a part of such efforts,
the Japanese Diet has approved the “Act on the Purchase of Renewable Energy
Sourced Electricity by Electric Utilities (Act)”, which is a feed-in tariff regime for
renewable energy, effective from 1 July 2012. Under the Act, electric utility
244
K. Nakamichi et al.