Disaster research refocuses on climate-related flooding
Japan is building research into recent climate change-related extreme events, in particular major typhoons in 2019, to draw up new disaster reduction measures, including measures to protect Olympic Games sites.
The measures will mean Tokyo will be able to operate during the Games in the event of a natural disaster such as a typhoon or earthquake. It includes new infrastructure to manage storm water runoff and prevent flooding in areas of Tokyo.
The two major, unexpected typhoons which hit the country in September and October 2019, causing extensive damage in the northeast areas, jolted authorities into approving extra budgets and conducting a review on the effectiveness of its world-class disaster management research and technology. According to a December 2019 report from the Ministry of Land, Infrastructure, Transport and Tourism, the ministry is deciding on new fund allocations from 2020 for flood control measures.
A 2018 White Paper on Disaster Management issued by the Environment Ministry said the frequency of short-duration downpours has been steadily increasing, attributing the change to global warming.
“A major shift in Japan’s disaster policy is the new emphasis on typhoons and its devastating consequences that weather experts have linked to climate change. This marks a departure from the traditional focus on earthquakes and tsunamis identified as the leading disasters [for Japan],” says Professor Koji Ikeuchi, a disaster expert at Japan’s prestigious University of Tokyo.
Typhoon Hagibis hit Japan in October 2019 and caused 98 deaths and 140 levee breaches along 71 rivers in seven prefectures in northeast Japan. Hourly precipitation including rainfall of 50 millimetres – or 2 inches – has increased 1.4 times and is linked to climate change, according to Ikeuchi’s research.
Official estimates put the total economic damage at JPY218.5 billion (almost US$2 billion) across 38 prefectures.
One of the most difficult issues faced by authorities was restoring power when electrical lines were submerged, causing blackouts in the damaged areas for months, experts said.
Ikeuchi, a civil engineer, is also director general of the university’s Earth Observation Data Integration and Fusion Research Initiative, which concentrates on water-related disasters and disaster risk management. Data from the research initiative indicates Japan faces a major risk from river flooding as the majority of Japan’s rivers have a steep and short descent to the sea resulting in rapid flow.
Many urban areas are also located below the river level, making these areas vulnerable to flood damage.
Climate change-linked typhoon resilience
After Typhoon Hagibis, Prime Minister Shinzo Abe announced an emergency budget of JPY138 billion for 2019 and fiscal 2020 to assist post-typhoon reconstruction. Japan has already launched a three-year programme through fiscal 2020 to strengthen preparedness and resilience with a new JPY7 trillion package.
The funds are also going towards creating new hazard maps. Other measures include revising evacuation orders by setting up stringent standards for fire alert levels and support for more community preparation such as drills, and official volunteer lists are being drawn up across Japan.
Japan is also spearheading an international typhoon study with universities in the United States, Taiwan and South Korea to improve typhoon forecasts, according to the Japan Meteorological Agency.
The project will be based on aerial observations of typhoons to collect data on atmospheric pressure, wind speed and other parameters, sharing the information with other countries and regions to improve disaster preparedness.
Learning from disasters
Professor Rajib Shaw, a disaster expert at the Graduate School of Media and Governance at Keio University, points out that the recent measures emphasise lessons learnt from analysis of disasters – a major reason Japan continues to be globally eminent in disaster research and resilience.
“In Japan the focus in the official, non-official and academic community is to enact new disaster reduction measures based on examining closely the damage from the tragedy and to prevent that loss in the future,” he said.
Shaw, who focuses on community-level disaster management measures, adds that research and analysis of disasters feeds into diverse sectors such as policy reforms, adoption of new legislation at the national and local level and raising the profile of community education.
Anniversaries of major disasters are observed in media-covered memorials over decades during which residents revisit the damage and take preparatory steps.
For example, research from the huge damage caused by the 1995 Hanshin Earthquake that hit Kobe city led to major policy changes such as officially recognising the importance of community-level action as a first step during an emergency. Administration officials have pushed for Kobe to become a main centre for international conferences on disaster management.
Past floods have also led to amendments to existing flood-risk laws.
In 2015, after a series of local floods caused by increasing rain resulting in inundation damage, the Japanese government passed a law that highlighted the need to publish flood and storm surge predictions and also obliged municipalities in flood-prone areas to determine how to transmit flood forecasts, information and evacuation routes.
Another important result of Typhoon Hagibis, which badly affected Nagano Prefecture, was that in December it became the first prefecture in Japan to declare a Climate Emergency – a non-binding promise to act at the necessary scale and speed to reduce carbon emissions, purchase renewables and take action to reduce climate change.
On the research front, Shaw said the focus on transdisciplinary studies is another strength in Japan, where preparing for disasters is a subject not only in science and technology, but is also incorporated into medical studies, humanities, economics and community development.