CLIMATE CHANGE AND JAPAN: EMISSIONS, WARM SEAS, EFFECTS, IMPACTS

CLIMATE CHANGE IN JAPAN

Temperatures in Japan have risen one degree nationwide in the past century and two to three degrees in the cities, where there has been a sharp increase in the number of days with temperatures exceeding 30 and 35 degrees.

Japan’s national average temperature has risen by between 0.2 to 1 degree C in the past decade It is estimated that by the year 2050, Tokyo could have more than 100 days a years with temperatures above 30 degrees C. In the early 2000s a big deal was made when temperatures in Tokyo exceeded 30 degrees C for 35 days in a row.

Scientists predict temperatures will rise 4.7 degrees by the ed of the 21st century, with temperatures being particularly high in the northern latitudes with the temperatures increasing by 5.8 degrees in Hokkaido.

According to survey conducted by the National Institute for Environmental Studies 95 percent of Japanese said they have noticed climate changes. Those who said they had noticed changes in temperatures were asked to give multiple serious scenarios that could result from climate change. According to the results, 46.4 percent of respondents, the largest number, said more extreme weather changes would occur, while 42.2 percent predicted sea levels would rise--results similar to those predictions by experts. However, 40.5 percent of responses predicted the gradual destruction of the ozone layer, which is caused mainly by chlorofluorocarbons, suggesting some people misunderstood the problem. [Source: Yomiuri Shimbun, March 29, 2007]

Websites and Sources: Ministry of Environment env.go.jp/en ; National Institute for Environmental Studies nies.go.jp ; Japan for Sustainability japanfs.org ; Wikipedia article on Environmental Issues in Japan Wikipedia ; Japan Environment Association jeas.or.jp ;
Statistical Handbook of Japan stat.go.jp ; Air Pollution in Japan (1964) ncbi.nlm.nih.gov ; Research Institute of Innovative Technology rite.or.jp ; Aozora.or Aozora.or ; ; Google E-Book: Japan in the 21st Century, Environment, Economy and Society (2005) books.google.com/books ; Wikipedia article on Climate Change in Japan Wikipedia

Greenhouse Gas Emissions by Japan

Japan is one of the largest greenhouse gas emitters, both as a country and on a per person basis

Greenhouse gases are gases in the Earth's atmosphere that trap heat from the sun. They let light pass through, but they absorb the heat that the planet radiates back out. This natural process keeps Earth warm enough to support life, but extra gases from human activities trap too much heat and cause global warming. The main type of greenhouse gase is carbon dioxide (CO2), which is released by burning coal, oil, and gas, as well as by cutting down trees. It is the main driver of modern climate change. Methane (CH4) is another important greenhouse gas. It is released during fossil fuel production, from livestock like cows, and from rotting trash in landfills. It traps a lot of heat very quickly. Nitrous oxide (NO2) comes from farm fertilizers and burning fossil fuels. Water vapor (H2O) is the most common natural greenhouse gas in the air. It amplifies warming as the planet heats up. Fluorinated gases — man-made chemicals used in things like refrigerators and air conditioners — do not occur naturally and stay in the air for a long time. They are blamed for the ozone hole.

Japan ranks fifth in the world in annual carbon dioxide emissions, according data by Worldometer's Global CO2 Emissions Rankings and World Population Review. It accounts for about 2.5 percent of global carbon dioxide emissions, releasing approximately 972 million metric tons annually. Although Japan remains among the leading emitters, its share of global emissions has declined over time as emissions have grown rapidly in developing economies, particularly China and India, while Japan has reduced its own emissions.

Carbon dioxide emissions: 960.23 million metric tonnes of CO2 (2023 estimate); from coal and metallurgical coke: 367.144 million metric tonnes of CO2 (2023 estimate); from petroleum and other liquids: 403.042 million metric tonnes of CO2 (2023 estimate); from consumed natural gas: 190.043 million metric tonnes of CO2 (2023 estimate). Methane emissions: energy: 214.7 kilotonnes (2022-2024 estimate); agriculture: 972.8 kilotonnes (2019-2021 estimate); waste: 208.2 kilotonnes (2019-2021 estimate); other: 22.7 kilotonnes (2019-2021 estimate). [Source: CIA World Factbook]

China is by far the world's largest carbon dioxide emitter, producing about 13.1 billion metric tons annually, or approximately 33.1 percent of the global total. The United States ranks second with about 4.6 billion metric tons, or 11.7 percent of global emissions. India is third with roughly 3.1 billion metric tons (8.0 percent), followed by Russia with about 2.0 billion metric tons (5.1 percent). Japan ranks fifth, emitting approximately 972 million metric tons, or 2.5 percent of the world's total.

Proportion of carbon dioxide emissions in Japan by sector in the 2010s: 1) industry (38 percent); 2) transportation (21 percent); 3) commercial (commerce, offices, stores, schools, hospitals, 20 percent); 4) households (14 percent ); and 5) energy (7 percent). While industry has been able to cut emissions by 5.5 percent in recent years emissions from the transportation sector has increased 18.1 percent, emissions from the commercial sector have increased 44.6 percent, emissions from households have increased 36.7 percent and emissions from the energy sector have increased 15.7 percent.

Reduction of Greenhouse Gas Emissions by Japan

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Greenpeace Meeting Japan's carbon dioxide emissions reached their highest level in fiscal year 2013, totaling about 1.4 billion metric tons. At that time Japan ranked fourth in the world in carbon dioxide emissions. At that time it produced 4.8 percent of world’s carbon dioxide compared to around 22 percent by the United States and 22 percent by China. The increase followed the 2011 Fukushima Daiichi nuclear disaster, when nearly all of the country's nuclear reactors were shut down and electricity generation shifted heavily toward coal, oil, and liquefied natural gas. Since then, emissions have declined steadily as energy efficiency improved, renewable energy expanded, and several nuclear reactors resumed operation.

Carbon dioxide emissions increased by 10 percent between 1995 and 2005. In 2006, emissions were 7.8 percent above the 1990 Kyoto protocol standard. The production of climate change gases in 2007 was high as a result of a nuclear plant closure and a heat wave. In the 2000s Japan’s power sector created 400 million tons of carbon dioxide, compared to 2,790 million produced by the United States and 2,680 million produced by China The transportation sector generated 261.5 million tons of carbon dioxide. There is a movement to get more people to take trains because they produce less carbon dioxide than cars or planes.

According to Japan's Ministry of the Environment, Japan’s total greenhouse gas emissions have now fallen below 1 billion metric tons, marking a significant reduction from the 2013 peak. The decline reflects greater use of renewable energy, the gradual restart of nuclear power plants, improvements in industrial efficiency, and government policies aimed at reducing greenhouse gas emissions. Japan has pledged to achieve carbon neutrality by 2050 and continues to promote low-carbon technologies while balancing energy security and economic growth.

Effects of Climate Change in Japan

A report by Intergovernmental Panel on Climate Change (IPCC), a United Nations organization, on climate change said that in Japan: “Further increases in temperatures in urban areas due to absorption of increased solar radiation will have negative implications for energy and water consumption, communications, transportation, water run-off and water quality, human health and discomfort and local ecosystems.”

Japan is predicted to have higher rain fall from climate change as a result of an “increase in atmospheric moisture availability,” much of it from typhoons and storms that present a flooding threat. The affects of climate change are expected to be most profound in the southern past of Japan, particularly Kyushu, which are expected to be hurt by a double whammy of high temperatures for a longer periods of time and more frequent and powerful typhoons. Super typhoons as strong as Hurricane Katrina that devastated New Orleans are expected to hit Japan over the coming decades with climate change perhaps being one of the causes of their megastrength.

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climate change could threaten animals
like this giant flying squirrel Tokyo, Osaka and other coastal cities are particularly vulnerable to sea level rises associated with climate change. If sea levels rise by 40 centimeters by the 21st century as they are expected to 2,339 square miles of land, occupied largely by large cities, would be affected. If sea levels rise one meter 90 percent of Japan’s beaches and many tidal mudflat, important feeding ground for birds and fish, will disappear The government is already preparing to spend huge amounts of money to build sea walls and take other measures to protect urban areas from rising seas.

A study by Japan’s National Institute of Environmental Studies and Ibaraki University predicted that climate change will cost Japan around $170 billion a year by the end of the century if the problem is not addressed. The costs include $83 billion from rain-induced floods, $74 billion from floods caused by high waves, $9.4 billion from landslides, $2.4 billion resulting from a decrease in beech forests, $430 million in sand erosion from beaches, $1.19 billion in damage to people’s health. Most of the damage is linked to increased rain from heavy storms, rising sea levels and rising temperatures.

Effects of Climate Change on Flora, Fauna and Disease in Japan

Climate change could squeeze out plants and animals that live in delicate alpine and northern regions. Already tropical plants are growing in subtropical areas and subtropical plants are growing in temperate areas and crabs and fish normally found in tropical waters have been found in normally temperate waters off Japan. The beech forests in northern Japan are expected to disappear while the number of allergy-causing Japanese cedars is expect to increase. Beeches thrive in regions with cool summers and lots of snow in the winter. They are threatened and already being pushed northward by climate change.

Other changes that have already occurred include changes in the flowering of cherry trees, a decease in alpine flora in Hokkaido and high mountain areas and an expansion of the distribution of broadleaf evergreen trees. Cicada species are advancing northward. The okojo — an ermine that is found primarily in forested and alpine regions of northern Honshu and Hokkaido — loses its white winter coat in early April, weeks earlier than it did in the 1980s and starts getting the coat in December, weeks later than it did in the 1980s. Warm winters and climate change are seen as the reason why. The pack ice that forms north of Hokkaido is threatened by climate change. A number of animals such as Stellar sea eagles and seals depend on the pack ice as they search for food.

There are also worries about disease. Climate change could bring mosquitos that carry malaria, dengue fever and West Nile fever into southern Japan. Already dengue-fever-carrying mosquitos, once found only on tropical areas, have ben found within 60 miles of Tokyo. In 2005, mosquitoes that transmit dengue fever were found in Akita and Iwate prefectures in northern Japan. Ciguatera, a type of food poisoning associated with tropical fish, has been found in fish caught off of Honshu. Some have attribute the appearance of the disease to warming waters caused by climate change.

Effects of Climate Change on Agriculture and Rice Farming in Japan

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Climate change in Japan could disrupt the annual monsoon rains that rice farmers depend on and cause severe drought and strong storms. It has already blamed for causing some grapes to turn red, making the inside of peaches develop an unusual brown color and causing oranges to drop from tree while they are still green,

Climate change may cause agricultural areas to shift northward. This could mean that oranges could be grown in area that are too cold for them now and yields of koshihikari rice will be reduced and the rice itself could be less tasty. There are worries that fisheries for important fish such as saurum mackerel and sardine will shift northward. One study found that rising temperatures and extreme weather caused by climate change could cut Japan’s rice yield by 40 percent by the end of the 21st century with much of the damage being done in central and southern Japan. Much of the damage would come from typhoons, heavy rains and “heat induced flora sterility.”

In recent years high summer temperatures and either too much rain or too little have negatively affected rice harvests. High temperatures cause poor yields and produce immature grains with poor starch content. Some blame climate change. One rice expert told Reuters, “The 20 or so days after the ear of the rice has appeared is most crucial...and high temperatures during that period leads to the production of immature grains.”

Farmers are starting to experiment with heat-resistant strains of rice. These taste significantly different than the usual strains and some expect to may take more than a decade for them to be embraced by consumers. Some Japanese insist that climate change has affected the taste of rice. A chef at an upscale restaurant in the Ginza district of Tokyo told Reuters, “In the past I could really savor the flavor of rice with just a sprinkling of salt. This isn’t a scientific point if...but the past four or five years, it’s become rare to have rice that I really find tasty.”

Heat Waves and More Frequent Extreme Weather in Japan Because of Climate Change?

Japan has experienced unusually high summer temperatures in recent years and long, deadly heat waves. Many blame climate change. According to United Nations IPCC report: It is expected that Japan's hot summers will become even hotter. The number of days with temperatures of 30 degrees C or above may double in some places. In Hokkaido the number of days over 30 degrees is expected to triple to about 100 days by 2100. Typhoons are expected to increase in ferocity and rising sea levels could produce massive coastal erosion.

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Japan's climate change research satellite In January 2012, the Yomiuri Shimbun reported: “Japan witnessed weather irregularities in the summer of 2012. Typhoon No. 12 registered the largest rainfall on record, and Typhoon No. 15 saw evacuation recommendations issued to as many as 1.22 million people in Aichi Prefecture and elsewhere. According to statistics from the Meteorological Agency, heavy rain in Japan has been on the rise over the past 100 years or so. Although the cause behind the increased rainfall remains unknown, some scientists believe it may be linked to global human activities. [Source: Yomiuri Shimbun, January 18, 2012]

“As Masahide Kimoto, vice director of the University of Tokyo's Atmosphere and Ocean Research Institute, puts it: "As the earth's climate changes, antidisaster preparations should be thoroughly reviewed, starting with city planning. Conventional wisdom can no longer cope with the situation.” In the case of extreme weather conditions, experts have said preventative measures have limits. A Japanese government Land, Infrastructure, Transport and Tourism Ministry council discussed transitioning away from conventional thinking that aims to prevent flooding in all rivers. The council also said it would be difficult to prevent all damage in the event of future, harsher disasters.

Effects of Climate Change on Ocean Currents in Japan

There are fears that climate change could disrupt the ocean currents around Japan and cause considerable damages to fisheries that Japanese depend on for food and dramatically disrupt Japan’s weather. Particularly vulnerable are the currents in the Sea of Japan that carry live-giving oxygen to deep water and bring plankton to the surface.

The Sea of Japan current is created by a rare phenomena in which harsh bitter winds blowing through an opening in a mountain range in the Russian Far East cool the sea in such a way that it triggers a downward current.

The water temperatures in the Sea of Japan have risen by 1.5 degrees C to 3 degrees C in the past 50 years. The fear is that if the sea warms too much the current will fail. The Gulf-Stream-like Kuroshio current off the east coast of Japan is also regarded a vulnerable to temperature changes.

Warming Seas Around Japan

The seas around Japan are warming at a rate of more than double the global rate. According to the Japan Meteorological Agency (JMA), the annual average sea surface temperature around Japan has increased by 1.36°C per century from 1900 to 2025. This is more than twice the average increase for the world's oceans, which is 0.63°C per century, and is close to the rate at which Japan's average land air temperature has risen (1.44°C per century). Scientists attribute this warming primarily to human-caused climate change, although natural climate variations also influence regional conditions. Rising sea temperatures are changing marine ecosystems, weather patterns, and coastal environments throughout the Japanese archipelago.[Source: Japan Meteorological Agency, March 6, 2026]

The rate of warming varies across different parts of Japan's surrounding seas. Some of the fastest warming has occurred in the central and southwestern Sea of Japan, the Pacific Ocean off Sanriku in northeastern Japan, and the waters off Shikoku and Tokai. Particularly rapid warming has also been observed in the Sea off Kushiro and the central Sea of Japan, where temperature increases exceed the national average. Other regions, including waters east of Okinawa and around the Sakishima Islands, have warmed more slowly but still show significant long-term increases. Nearly all regions around Japan display statistically significant warming trends.

Several factors contribute to the rapid rise in sea temperatures. The Intergovernmental Panel on Climate Change (IPCC) concludes that human activities have unequivocally warmed the atmosphere, oceans, and land through increased greenhouse gas emissions. Around Japan, the warming trend is reinforced by the Kuroshio Current, a warm western boundary current that transports tropical water northward along Japan's Pacific coast. Variations in the Kuroshio Extension and natural climate patterns such as the Pacific Decadal Oscillation (PDO) also affect regional temperatures from year to year. Together, these factors have produced higher average sea temperatures and more frequent periods of unusually warm water.

Marine heatwaves have become increasingly common around Japan as ocean temperatures continue to rise. During these events, sea surface temperatures remain well above normal for extended periods, placing stress on marine ecosystems. Warmer surface waters reduce winter mixing between surface and deeper layers of the ocean, limiting the circulation of oxygen and nutrients. This can affect plankton growth, fisheries productivity, and the overall health of marine habitats. Scientists expect marine heatwaves to become more frequent and more intense as global temperatures continue to increase.

Impact of Warming Seas Around Japan

Rising sea temperatures are transforming Japan's marine ecosystems. Coral reef ecosystems are also responding to warmer seas. In southern Japan, especially around Okinawa, repeated marine heatwaves have caused widespread coral bleaching, in which corals expel the algae that provide much of their energy. Severe bleaching can weaken or kill coral colonies if high temperatures persist. At the same time, some tropical coral species have expanded northward and established new colonies in areas such as Tokyo Bay, reflecting the gradual warming of coastal waters. These changes are altering the composition of marine habitats and the species they support.[Source: Japan Meteorological Agency, March 6, 2026]

Warmer oceans also influence Japan's weather and climate. Higher sea surface temperatures increase evaporation, adding more moisture to the atmosphere. This extra water vapor can intensify typhoons, strengthen heavy rain systems such as linear rainbands, and contribute to more extreme snowfall when cold winter air passes over relatively warm seas. Warm coastal waters also increase humidity during summer, making heatwaves feel more oppressive and increasing the risk of heat-related illness in urban areas. Scientists are continuing to study how warming oceans affect Japan's changing weather patterns.

Researchers emphasize that rising sea temperatures are one of the clearest indicators of ongoing climate change in the region.In aquaculture, unusually warm summer water has caused disease outbreaks and mass die-offs of farmed species, including scallops and oysters, resulting in significant economic losses for coastal communities. Seaweed used to produce nori has also been affected, with warmer waters shortening growing seasons and reducing harvests in some regions.

Impact of Warming Seas Around Japan on Fishing

Rising sea temperatures are transforming Japan's fishing industry. Many cold-water species that have traditionally supported commercial fisheries are declining as their preferred habitat becomes warmer. Catches of Pacific saury, chum salmon, and other cold-water fish have fallen sharply in recent years.[Source: Japan Meteorological Agency, March 6, 2026]

At the same time, many warm-water species are expanding their range northward. Fish such as yellowtail (buri), several species of mackerel, and other subtropical marine animals are now commonly found much farther north than in the past, including waters around Tohoku and Hokkaido. Some fisheries have benefited from these new arrivals, but many traditional fishing operations have had difficulty adapting to rapidly changing species distributions. Scientists expect these shifts to continue as ocean temperatures rise. Changes in migration patterns also affect marine food webs and ecosystem balance.

Cold-water species are increasingly moving into higher latitudes, including Russian waters. Returns of chum salmon to rivers in Hokkaido and the Tohoku region have fallen as warmer coastal waters reduce survival rates and alter migration patterns. Catches of Pacific saury and Japanese flying squid kelp have also declined, while fish are often smaller than in the past. [Source: Seafood Legacy Times]

In contrast, some Russian fisheries have benefited from the northward movement of cold-water species. Cooler waters along Russia's Pacific coast have become increasingly favorable for salmon and other species seeking lower temperatures. Scientists have also observed changes in the Sea of Japan, where warmer conditions have allowed species normally associated with more southern waters, including tuna, to expand their range and create new commercial fishing opportunities.

Image Sources: 1) JAXA 2) Japan-Animals blog 3) JNTO 4) 7) Greenpeace Japan 5) 6) Osaka Ga, Wikimedia Commons, NASA,

Text Sources: Japan’s Ministry of Environment, Library of Congress, CIA World Factbook. Daily Yomiuri, Japan National Tourist Organization (JNTO), National Geographic, New York Times, Washington Post, Los Angeles Times, Smithsonian magazine, Encyclopedia.com, Live Science, The Conversation, The New Yorker, Time, BBC, CNN, Reuters, Associated Press, AFP, Lonely Planet Guides, Google AI, Wikipedia, The Guardian and various websites, books and other publications.

Last updated August 2026