Effects of Climate Change in Japan:

Adaptation and Mitigation Strategies

Arisa Mizunuma

May 19th, 2016

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Table Contents

I. Introduction………………………………………………………………………………......... 2

Biography…………………………………………………………………….……....……..…3

Climate Change…………………………………………………………………….…...…..…3

II. Climate Change Impacts……………………………………………………………………….3

1. Impacts on Physical System……………………………………………………………….3

Sea Level Rise…......………………………………………………………………………4

Floods……………………………………………………………………………………...4

2. Impacts on Social System…………………………………………………………………5

Heat Stroke………………………………………………………………………………..5

3. Impacts on Biological System……………………………………………………………...5

Cherry Blossom and Acer Leave………………………………………………………….5

III. Mitigation and Adaptation……………………………….……………………………………6

Mitigation Strategies..................................................................................................................6

Adaptation Strategies………………………………………………………………………….7

IV. Conclusion…………………………………………………………………………………….8

V. Referenced Cited……………………………………………………………………………….9

I. Introduction

As greenhouse gas emissions increased due to anthropogenic activities, climate has been

changed in Japan. This paper analyzes climate change in Japan. In the sections of “climate

change impacts” are considered followed by an analysis of climate change impacts on physical

system, biological, and social system in Japan. In the following sections “Mitigation and

Adaptation” shows that mitigation strategies, which are using renewable energy to decrease

greenhouse gas emissions, and adaptation strategies to decrease the risk of getting floods. In

Japan, climate change has raised the temperature and the number of heavy rains and it impacts

on physical, social, and biological system. It is required for Japan to adapt and mitigate climate

change to continue to live in Japan.

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Biography

Japan is a country that is part of East Asia in the Western Pacific Ocean. Comparing with

the U.S. and Asian mainland, Japan is a quit small island country and the total land scale of

Japan is about 140,000 square miles. Although Japan is a small country, it has a large population.

The current population in Japan is 126,361, 827 and the population rank is 11th. The climate of

Japan is distinguished by four seasons, which are winter, spring, summer, and autumn. In winter

seasons, it is often dry and sunny on the Pacific coast and it is often snow in northern Japan.

Summer begins with three or four weeks of heavy rain season that is significant to grow rice, and

the climate is hot and humid during summer seasons in all of Japan. The average temperature of

Tokyo, which is the capital city of Japan and located on the Pacific coast, is 4.7C (40.4F) in

winter, 18.4C (65.1F) in spring, 26.7C (80.06F) in summer, and 17.3C (63.1F) in autumn.

Annual rainfall averages are nearly 1,530 millimeters (60.2 inches), with wetter summer seasons

and drier winter seasons. Annual greenhouse gas emission of Japan is about 1.3 million metric

tons and it makes Japan the 5th largest emitter of greenhouse gas emissions country.

Climate Change

Climate change due to increasing of greenhouse gas emissions is occurring in Japan now.

Average annual temperature has risen by 1.0C over the last century. The number of hot days

(with maximum temperature higher than 35C, 95F) and the number of days with heavy

participation has increased. The frequent and extreme weather events such as tropical cyclones,

heat waves, and heavy rainfall events are projected to increase in the future.

II. Climate Change Impacts

1. Impacts on Physical System

Sea Level Rise

Nowadays, annual rate of sea level rise is 1 to 3 mm in the coastal area of Asia, but in

japan, sea level has been rising 3.3 mm per year since the middle 1980s. Japan has one of the

fastest annual rates of sea level rise of the Asian countries. According to Konishi (2007), the

maximum rate of sea level rise was recorded in Kushiro, which the city located in northern

Japan. Sea levels had increased 9.3mm per year between 1970 and 2003 in Kushiro. Increasing

sea levels threaten Japan’s coastline, which contains a large part of the population and many

economic activities. In Japan, more than 30 million people live within 10 km of the sea (Konishi,

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2007). Although coastal areas are only 32 % of the total land of Japan, they are occupied by 46

% of total population and produce 47 % of industrial output. Sea level rise will decrease the area

of these costal areas in Japan if climate change continues. In fact, the increasing 0.26 m average

sea levels decrease more 40% of Japan’s sandy beach and Japan would lose 90 % of their sandy

beach with 1-meter sea level rise (Figure1) (Harasawa, 2006.)

Figure1: The curve of beach loss late in Japan for the sea level rise of 0 m to 1m.

Flood

The annual participation in Japan varies largely from year to year, and it is not clear what

trends of increases or decreases have been observed. However, the number of days with heavy

rainfall has been increasing due to global warming. Over the last 30 years, the number of heavy

rain days with a daily rainfall of 200 mm has increased to about 1.5 times that of the first 3

decades of the 20th century in Japan (Hamada and et al, 2008). Therefore, the risk of flooding is

rising due to increasing of heavy rainfall days. In the future, floods causes of heavy rainfall are

projected to be about 3 times higher than current levels in Japan (Nomoto, 2013). The Japanese

government explains that climate change has increased frequent and extreme weather disasters

such as floods which impact on Japan’s economy.

2. Impact on Social System

Heat Stroke

Climate change due to increasing of greenhouse gas emissions already affects health in

Japan. As the temperature rise, the risk of getting human heat stroke has been increased since

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2010 (Figure2). Before 2010, the average people who died because of heat stroke was around

about 200 to 300 but it has increase after 2010 because the number of hot days, which is above

35C, have increased since 2010. On July 2015 in Tokyo, more than 24,000 people were taken to

hospitals by ambulance because of heat stroke, and 39 people died (Tsujimoto, 2012). In this

year, the number of people who got heat stroke was larger than usual since this summer’s

temperature was higher than the normal average summer air temperature. The usual average

temperature of July is about 25C in Tokyo but the average temperature on July 2015 was 27C,

and 8 days of this month were recorded at more than 35C (95F). Tsujimoto (20152) shows that

the risk of getting heat stroke increased rapidly if the temperature increased above 28C. Average

annual temperature and the number of hot days (with maximum temperature higher than 35C,

95F) have increased in Japan now especially in urban areas such as Tokyo (Konishi, 2007.)

Although the annual average temperature increases about 1C per century in Japan, it increases

about 3 C over the last century in Tokyo. The average temperature has increased in the other

large Japanese cities, including, Sapporo, Sendai, Kyoto, and Osaka is more than 2 Cover the last

century. Increasing temperature in urban areas is bigger than in suburban areas because of

anthropogenic carbon emissions, subsea vent heat accumulations, and restraint of water

evaporation and transpiration when urban ground is covered with asphalt and concrete. The risk

of getting heat stroke is increased as temperature rises and people who live in urban areas have

more risk than suburban areas.

Figure2: The number of people who died because of heat stroke in Japan 1994 to 2013.

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3. Impacts on Biological System

Cherry Blossom and Acer Leave

Increasing temperature due to climate change impacts on cherry blossoms and Acer

leaves in Japan. In the recent years, cherry blossoms have been flowering earlier than the average

arrival of 20 century, and Acer leaves have started turning their color later than they used to.

Demetriou (2016) shows that cherry blossoms came five days earlier than the average arrivals

days of the last 3 decades in Tokyo in 2009, and it happened because of global warming.

Increasing the average of temperature in Japan make spring arrives earlier and cold season

arrives later. It makes cherry blossom flowering earlier and leaves change their color later.

III. Mitigation and Adaptation

Mitigation Strategies

Annual greenhouse gas emission of Japan is about 1.3 million metric tons and it makes

Japan the 5th largest emitter of greenhouse gas emissions country. Carbon emissions due to

human activities are the most important drivers of observed climate change since the industrial

revolution and the frequent and extreme weather events such as heat wave and heavy rainfall will

happen in the future in Japan if greenhouse gas emission levels continue to rise. Japan has to

decrease large amount of carbon emissions in order to mitigate climate change. In 2010,

Japanese government planed to use more nuclear power for Japan’s electricity because nuclear

energy can save large amount of greenhouse gas emissions comparing to other sources such as

oil and natural gas (Figure3 and Figure4). However, the big earthquake attacked Japan in 2011

and the government stopped most of nuclear plants. It made increase greenhouse gas emissions

because Japan used more natural gas and fossil fuel to make up for electricity instead of using

nuclear power. Before the earthquake happened in 2011, nuclear power provided 32 % of

Japan’s electricity, but it decreased to 2 % after the earthquake. To decrease greenhouse gas

emissions, Japan should use renewable energy such as solar and wind power instead of using

new clear power and other powers, which emit lots of carbon emissions such as fossil fuels or

natural gas. Providing electricity from fossil fuels and natural gas emits greenhouse gas

emissions far higher than when using nuclear or renewable power (See Figure3). Japan does not

have fuels for nuclear and other powers and they have to buy these fuels from other countries.

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They can save the cost of fuels and reduce greenhouse gas emission by using renewable energy,

and it is safer than nuclear power.

Figure3: Average GHG Emissions Intensity (GW/h) from Energies

Figure4: Energy use in Japan between 2010 to 2013

Adaptation Strategies

In Japan, anthropogenic climate change make increasing the risk of flooding through

more frequent heavy rainfall and increasing sea level rise. In 2014, Hiroshima City observed an

unanticipated precipitation rate of 101 millimeters per hour, resulting in a massive landslide that

left 75 dead. In 2015, the country experienced a flood disaster caused by heavy rains in the

Kanto and Northeastern region. Therefore, adaptation strategies for flood risk are required in

Japan to reduce negative impacts of climate change. The strategies for floods are building dike,

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developing and maintaining effective early warning systems, and providing a hazard map. The

government has to build dikes besides the river to protect people from water when river levels

are higher than usual because of heavy rainfalls. Japan also has to develop early warming

systems since people can evacuate to the safe place before floods happen if they get early

warning systems. A hazard map is required because people should know where has the higher

risk of flooding.

IV. Conclusion

Climate change is occurring in Japan now. The annual average temperature has increased

over the last century and the number of hot days, which is above 35C(95F), and the number of

heavy rainfall days has increased. These climate changes impact on Japan’s physical, social, and

biological systems. Sea levels have increased and the risk of flooding has risen. The number of

people who died due to heat stroke has increased because of increasing hot days with above 35C.

Cherry blossoms have been flowering earlier and Acer leaves have been turning their color later.

Japan will get more impacts of climate change if they will continue to emit greenhouse gases.

Therefore, Japan has to decrease greenhouse gas emissions to mitigate climate change, and they

should use renewable energy that can reduce carbon emissions. Japan also need to find effective

adaptation strategies for climate change that is happening right now in Japan.

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V. Referenced Citied

Demetriou, D (2016). Global Warming hits Japan’s cherry blossom season. The telegraph.

http://www.telegraph.co.uk/news/earth/environment/globalwarming/5052867/Global-warming-

hits-Japans-cherry-blossom-season.html

Konishi, M. (2008) Nippon Change-Climate Impacts Threating Japan Today and Tomorrow,

WWF

https://www.wwf.or.jp/activities/lib/pdf_climate/environment/WWF_NipponChanges_lores.pdf

Nomoto, T. (2013) Measures to produce national adaptation plan for climate change in Japan.

Global Environment Bureau.

http://www.iges.or.jp/isap/2013/PDF/PL9/first_half/ISAP_PL9_A3_TakuyaNomoto.pdf

Okazumi, T (2008) Adaptation Strategies for Climate Change in Japan. Asia Europe meeting.

http://www.mlit.go.jp/river/basic_info/english/pdf/conf_03-0.pdf

Tsujimoto. N. (2012) Climate change and its impact on Japan. Impact assessment of Climate

Change.

https://www.env.go.jp/en/earth/cc/impacts_FY2012.pdf

N.D.(2009) Climate change and Impacts in Japan. Ministry of Education, Culture, Sports,

Science, and technology.

https://www.env.go.jp/en/earth/cc/report_impacts.pdf

N.D (2016) Climate Change Knowledge Portable. The World Bank Group

http://sdwebx.worldbank.org/climateportal/index.cfm?

page=country_historical_climate&ThisRegion=Asia&ThisCCode=JPN

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