This year might best be remembered for the conflict in the Middle East or the return of Donald Trump in the U.S., but in climate circles, in Japan and elsewhere, 2024 will go down as the latest “hottest year on record.”
According to the Meteorological Agency, which released Japan’s climate summary for 2024 on Wednesday, average temperatures across the nation and surrounding seas exceeded last year’s record-breaking levels “by a significant margin.”
This year’s record temperatures — and extreme weather linked to warming — hit people’s wallets and well-being hard. They highlight the growing impact of climate change in the here and now, adding urgency to addressing its primary cause — the burning of fossil fuels.
The government is currently working to set new greenhouse gas emission reduction targets and the basic energy policy that will underpin them. On Tuesday, officials in a joint panel from the environment and trade ministries proposed a plan to cut emissions by 60% by 2035 and 73% by 2040, compared with 2013 levels, as part of its commitment to achieve carbon neutrality by 2050. But the plan was sharply criticized by climate-conscious businesses, think tanks and environmental activists, who fear the nation’s 2035 and 2040 goals are not aligned with international ambitions to curb global warming.
The plan will go through a public comment process before getting formally adopted by the Cabinet early next year.
The impact of the record temperatures was most severely felt over the summer, which tied with last summer for Japan’s hottest on record, with the three months from June being 1.76 degrees Celsius hotter than the 30-year average through 2020. The scorching heat impacted every aspect of people’s lives, as documented in depth by The Japan Times’ Boiling Point series.
More schools installed AC units and mist showers to offer respite from the heat, while some businesses worried about declining customer traffic offered “extreme heat” discounts to draw people back.
Unsurprisingly, the extreme temperatures took a toll on people – both mentally and physically. According to an online survey of 600 people in their 20s to 70s by Omron Healthcare conducted in August, more than 70% said extreme heat affected their health and lifestyles, such as by causing them to go out less, cut their amount of exercise or by reducing their opportunities to meet people. Some 40% of the respondents said they felt more stressed because of the heat.
But summer was not the only time the nation experienced unusual temperatures, with various records being broken throughout the year.
Unwelcome records
In February, western Japan witnessed the hottest temperatures for the month since such records began in 1946 — 2.4 C higher than average — while eastern Japan matched its hottest February on record with temperatures 2.1 C higher than normal.
On April 15, temperatures in Sapporo topped 25 C, passing the threshold at the earliest point of any year on record.
In fact, Japan’s average temperature for April was the highest on record, which experts attribute to the lingering effects of the El Nino climate phenomenon and global warming. The month’s temperature was 2.76 C higher than the average year.
Of course, the story doesn’t end there.
A pedestrian walks under cooling mist sprays in the Ginza district of Tokyo in July. This year, the Environment Ministry issued 1,722 heatstroke alerts across Japan, a record high since the ministry started issuing them in 2020.
| Bloomberg
Temperatures shot up in early July, even before the official end of the rainy season. On July 8, an observation point in the city of Shingu, Wakayama Prefecture, logged 39.6 C, the highest-ever temperature recorded in the city, while Fuchu, western Tokyo, saw the mercury rise to 39.2 C, also an all-time high.
The extreme temperatures in Shingu and Fuchu were made at least five times more likely because of climate change, according to U.S. nonprofit research group Climate Central. On a whole, the record heat seen across the nation that month was “almost impossible” without climate change, a joint analysis by the Meteorological Agency and the education ministry found.
In fact, all heat waves are now made more likely and more intense because of climate change, scientists say.
The JMA report released Wednesday said Japan’s annual average temperature for 2024 is expected to be 1.64 C higher than the average, significantly surpassing 2023 and marking the highest value since record-keeping began in 1898. In fact, the past six years through 2024 are all expected to rank within the top six hottest years on record, it says.
“Japan’s annual average temperature has been rising long term at a pace of 1.40 C per 100 years, with a notable increase in the frequency of high-temperature years since the 1990s,” the report says. “The progression of global warming has made such record heat more likely to occur.”
Record heat is having severe health consequences for the aging country.
This year, the Environment Ministry issued 1,722 heatstroke alerts across Japan, a record high since the ministry started issuing them in 2020 and a stark increase from last year’s 1,232. Such alerts are issued when the wet-bulb global temperature — a measure of heat’s impact on people based on a mix of air temperature, humidity and solar radiation — reaches 33 C or higher. The elderly are particularly susceptible to heatstroke, creating issues for the nation’s health care system.
A view of Mount Fuji from a shopping street in Fujiyoshida, Yamanashi Prefecture. The first snowcap of 2024 on Mount Fuji was delayed about a month amid record-setting temperatures in Japan throughout much of the year.
| Bloomberg
Japan went on to have the warmest fall on record, delaying the peak of the autumn foliage season by more than 10 days in many regions and the first snowcap of Mount Fuji by about a month, which this year was not observed until Nov. 6.
In an analysis released by Climate Central on Dec. 17, the city of Fuji, Shizuoka Prefecture, which sits on the southern foot of Mount Fuji, was found to have experienced 35 more days with a minimum temperature above freezing due to human-caused warming, logging the biggest increase among 901 cities analyzed around the world.
Economic impact
Undeniably, some businesses have benefited from the extreme weather. In October, as unusually warm days persisted, a record 439,000 air conditioning units were sold in Japan, a 13% increase compared with sales a year earlier, according to the Japan Electrical Manufacturers’ Association.
But many other businesses, particularly those in the farming and fishing industries, have suffered heavy losses. Yoshitaka Inoue, 44, who runs an organic vegetable farm in Hokuto, Yamanashi Prefecture, says that average temperatures in his community are 3 or 4 degrees higher than 23 years ago, when he started farming there. Now the business model of growing vegetables on cooler, high-altitude farmland is being threatened, he says.
Yoshitaka Inoue (left), a farmer in Hokuto, Yamanashi Prefecture, and Akira Nagakubo, a fisher in Hayama, Kanagawa Prefecture, say their livelihoods have been severely hit by climate change.
| TOMOKO OTAKE
“Our area used to get cool after the o-Bon holiday period (in mid-August), and I used to feel the fall arriving through the wind,” he says. These days, temperatures stay above 30 degrees until late September, he adds.
This has complicated the farming of autumn vegetables such as cabbage, broccoli and spinach, which are normally planted in late August to early September.
“Because the sun is so strong, we have to put light-shielding nets over the seedlings and water them. That’s an extra effort that wasn’t necessary over 10 years ago,” Inoue says. “And even then, the seedlings will often wither and die, as the soil gets dry.”
The poor harvest explains an extreme spike in the price of cabbage for two weeks in November, where an average cabbage costing ¥417 per kilogram — nearly three times the typical price.
Warming has also allowed pests to survive long past the summer and until mid-November, Inoue says. Because his farm doesn’t use pesticides, staff can only remove them by hand — or wait for the bugs to disappear and plant the vegetables all over again.
Land and sea
A hotter ocean is also hurting the businesses of fishers, including Akira Nagakubo, 39, who collects seaweed such as wakame and hijiki as well as shellfish like sazae (turban shell) and awabi (abalone) in Hayama, Kanagawa Prefecture. As ocean temperatures have stayed warm throughout the year, seaweed-consuming marine animals such as sea urchins and dolphinfish, previously only seen in tropical regions, have become active in Sagami Bay — her fishing ground — even in winter, she says.
That’s had a devastating impact on her bottom line.
“My income is one-tenth of what it used to be,” says Nagakubo, who has been fishing in the area for 11 years.
Behind the warming of Sagami Bay is the “great meandering” of the Kuroshio Current, which flows northward along the Pacific side of Japan.
The Kuroshio Current carries warm water that contributes greatly to Japan’s climate, marine ecosystem and fisheries — and troublingly it has recently exhibited an unusual outward loop around the Kii Peninsula in the Kansai region to avoid the blocks of cold water right underneath the peninsula. As a result, the deviated current brings more warm water into Sagami Bay, pushing sea temperatures up around Hayama.
Toru Miyama, a researcher at the Japan Agency for Marine-Earth Science and Technology who has monitored Kuroshio and Oyashio currents closely, says this phenomenon has been observed in six cycles since the Meteorological Agency started recording data in 1965, but the current one is by far the longest ever, lasting nearly 7½ years, compared with a year or two for most of the other periods.
A pedestrian walks past air conditioning units in Tokyo in July. Air conditioners sold well in 2024 and even into the autumn season as high temperatures persisted.
| Bloomberg
The current’s force is not strong enough to push the block of cold water away in waters off the Kii Peninsula, which explains why the current has continued its loop, Miyama says.
Equally astounding, the Kuroshio Current has extended northward along the coast to Iwate Prefecture, instead of taking the conventional path and veering east into the Pacific Ocean around Chiba Prefecture.
This extension of the current has pushed the sea surface temperature along the Tohoku coast higher than average by 5 or 6 C, according to Meteorological Agency data, greatly affecting the marine ecosystem and fisheries there.
Miyama says there is no scientific consensus on whether the ongoing looping of the current is attributable to climate change, though he adds that its unprecedented duration may be.
“The ocean temperature has increased by 1 or 2 degrees over the last 100 years, adding to the effect of the great meandering of the current. It cannot be said that the occurrence of the Kuroshio Current meandering itself is due to global warming, but global warming cannot be denied as a factor contributing to the looping of the current being the longest in history.”
While recent advances in event attribution studies have connected climate change to extreme weather much more quickly than before, scientists have not been able to do such studies related to the ocean due to a lack of data, especially on the seafloor, Miyama says.
Either way, the current meandering, which has hurt the livelihoods of Nagakubo and other fishers, will probably continue for at least through the first half of next year, he says.
“Combined with the recent rise in ocean temperatures in the Sea of Japan … there are fears that the seas surrounding Japan have reached an entirely new (temperature) level,” Miyama says.
