The Great East Japan Earthquake and Tsunami Aftermath: Preliminary Assessment of Carbon Footprint of Housing Reconstruction

The 9.0-magnitude Great East Japan Earthquake and the subsequent tsunami on March 11 of 2011 was the most devastating natural disaster ever to have hit Japan in its recent history. The aftermath of this catastrophic event is extensive, including a negative impact on the world-wide effort in mitigating global warming by carbon emission reduction. Not only has the Fukushima nuclear crisis dramatically slowed down nuclear power development as a low carbon alternative energy, but also the infrastructure reconstruction would come with a heavy carbon footprint. According to the statistic data released by the Japanese government, over 396,067 buildings were fully or partially destroyed, and more than 728,583 partially damaged in this disaster. The building reconstruction must consume large amounts of construction materials and energy, which would inevitably increase the greenhouse gas (GHG) emission. In this study, we identify housing construction, land use conversion to settlement, and earthquake/tsunami wreck clearance as three major GHG emission related processes of post disaster building reconstruction. We derive a first order estimate of the embodied GHG emission of these three processes based on official statistic data of damages, the quantification of major resources required for typical Japanese residential building types, and the IPCC Guidelines for National Greenhouse Gas Inventories. The result shows that the post Great East Japan Earthquake housing reconstruction alone has at least an emission of 26.3 million tons CO2 equivalent, or about 2.1 % of the total greenhouse gas emission of Japan in 2010.