Rising temperatures could cancel most outdoor school sports in summer by 2060s
School sports tournaments and club activities across Japan may need to be canceled for much of the summer by the 2060s as climate change pushes heat levels beyond safe limits, according to a joint study by the National Institute for Environmental Studies and Waseda University.
Millions of students across the country participate in school sports clubs, and thousands of heat-related illnesses have been reported almost every year since 2018.
Current Environment Ministry guidelines call for halting strenuous outdoor activities when the wet-bulb globe temperature (WBGT) remains below 28 degrees Celsius for less than two hours (referred to as Heat Level 1) and stopping all activities, indoors or outdoors, when it remains below 31 C for less than two hours (referred to as Heat Level 2). The WBGT is a measure that combines heat, humidity, wind and sunlight.
However, the study shows those thresholds could be reached much more frequently in the future, especially in regions that are already warm. The study warned that, in the coming decades, nearly three-quarters of the country could face conditions in which intense physical activities should be suspended for months at a time.
The study analyzed projected levels of the WBGT from 842 locations across Japan from the past 12 years. They split the country into eight regions and found that many would experience dangerous heat during peak school club activity hours, which are in the late afternoon.
In the worst-case scenario, with continued reliance on fossil fuels, six out of eight regions would experience Heat Level 2 requiring intense activities to be canceled at least once a week, and four zones would need to suspend all physical activities entirely.
Even under the most optimistic emissions scenario, five of eight climate zones would still require one to four months of restrictions on strenuous outdoor activities.
Common countermeasures, such as early morning practices or moving activities indoors, that are in place currently may reduce the risks, but the researchers found they would not be enough in the future. Even with these steps in place, up to four regions would still require monthslong restrictions under the worst-emissions scenario.
'If climate change progresses, continuing club activities in the same way as before will become difficult,' the researchers said.
They called for fundamental changes to how school sports are run, including shifting tournaments to cooler months and investing in indoor training spaces — steps that many regional schools may struggle to afford without government support.
Some national tournaments, such as the high-profile Koshien national high school baseball championship, have begun taking precautions by holding games in the morning and evening to avoid peak heat. However, local events often lack the resources to do the same.
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Japan Today
a day ago
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Is it OK to drink bottled water after the expiration date in Japan?
By SoraNews24 Let's say you're at home, going through your disaster preparedness kit, and you find a bottle of spring water you bought a long time ago in case of emergency. Checking by the cap, you see that the expiry date was a few months ago, and decide to use it to water plants or top off the washing machine instead of drinking it. Well, congratulations; you just wasted perfectly good water. Alright, 'perfectly good' might be an overstatement since we're still not sure what the microplastics floating around in there can do to us, and 'waste' is also a little harsh since plants are our friends too. But the point stands that you could have drunk that water and it would have been more or less as good as the day you bought it. This is because according to the Secretary General of the Japan Mineral Water Association, the 'expiration date' on bottled water isn't used for the same reason that it's used on perishable food. This is actually the date at which water inside the bottle is expected to have evaporated so much that the bottler cannot guarantee the amount written on the bottle is inside anymore and could be held liable for false labeling. Water bottles in Japan are usually made of a type of polyethylene terephthalate (PET), which is slightly permeable to water vapor. Some tests have found that when stored at around 25 degrees Celsius around two to three milliliters of water vapor can escape per month. Also, in the hot summer months of around 37 degrees Celsius, that rate goes up to about 4 milliliters per month. Meanwhile, the Measurement Act of Japan states that the actual contents of a bottle must be no less than two percent under the amount listed on the label for bottles under 500 milliliters and no less than 10 milliliters less than the labeled amount for bottles 500 milliliters and up. So, bottlers of water simply calculate the rate of evaporation and release through the PET bottle, apply it to the legal threshold, and an expiry date is born, but it's not the water that expires. It's the label on the bottle that does. Of course, this is a separate subject from contamination from chemicals inside the plastic of the bottle, and it's possible both things could be occurring at the same time. But since evaporation happens rather quickly, would there even be enough time for significant amounts of potentially hazardous chemicals to seep into the water from the plastic? Going by the rate of evaporation found in studies, at two milliliters per month we can expect a 500-milliliter bottle to be empty in 20 years and 10 months. In the case of chemicals from the plastic entering the water, known as 'leaching,' the most worrisome elements are antimony and germanium. Under normal storage conditions, it would take about 71 years for enough antimony to enter the water to surpass Japanese safety standards and about 15 years for the germanium levels to surpass those deemed safe. Mind you these are just the standards, which tend to err on the side of caution, meaning one 15-year-old 500-milliliter bottle of water — wait… 140-milliliter at that point — probably won't send you straight to the ER. Even factoring in things like the lower concentration of water as it evaporates and the diminished leaching as the surface area shrinks, you're still looking at about a good nine years or so before standards are exceeded. One big caveat to all this is that it only applies to Japanese water that has been sterilized to Japanese standards and in bottles made to Japanese standards. Every country has its own standards, including what it considers the allowable limits of antimony and germanium to be, so do your own research before consuming 10-year-old bottles of water anywhere outside of Japan. Microplastics are also still a bit of a wildcard, in terms of their effect on the human body and how rapidly they break down in a typical Japanese PET bottle of water. Most microplastics are said to enter the water during bottling at the factory, so the bulk of it will already be present in a brand-new bottle anyway, with only a relatively moderate increase over time if stored securely. Unfortunately, there don't seem to be any studies on microplastic contamination over very long spans of time, such as 10 years. ▼ In other words, if you're worried about microplastics you really shouldn't even be drinking new plastic bottles of water. Image: SoraNews24 This information has recently been trending online in Japan and many came out in agreement with it, either using their own theoretical knowledge or personal experiences. Others still felt it wasn't worth the gamble. 'If the water can escape, can't things like bacteria get in?' 'Molecules like water and carbon dioxide are 0.3 nanometers, about the same as gaps in permeable plastic, but a virus is about 20 nanometers so it can't get in.' 'If I leave water out, I just use it for laundry.' 'I'm still just going to use it for cleaning and watering plants.' 'Water is always fine, isn't it?' 'I had some water that I'd been keeping for seven years in case of emergency. I drank it when I replaced it and it was fine.' 'I've been given expired ones before and there definitely seemed like less water inside.' 'If the bottles are breathable I probably shouldn't store them next to the toilet.' 'If the bottle is shriveled that's good because the air pressure outside is collapsing it. If the bottle is old and a normal shape, air has gotten inside and there might be bacteria too.' 'I'm still going to pour it down the drain anyway. Why take a chance?' Whether you're willing to crack open a seven-year-old bottle of Japanese water is entirely up to you, but the key takeaway from all this is that the expiration date written on it has absolutely nothing to do with its quality, so feel free to hang onto it at least a little bit longer than that. Sources: Yahoo! Japan News, The Sankei Shimbun, withnews, Ministry of Economy Trade and Industry, Japan Soft Drink Association, Japanese Journal of Food Chemistry and Safety, Food Safety Commission, Hachima Kiko Read more stories from SoraNews24. -- Japanese Twitter calls out crazy bottled water claims, gets us thinking about what we're drinking -- Leading bottled water brand in Japan goes label-free to reduce waste, angers many -- Internet reacts with confusion to Muji's new fill-it-up-yourself water bottle product External Link © SoraNews24
SoraNews24
2 days ago
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Is it OK to drink bottled water after the expiration date in Japan?
The answer may not surprise you but the reason will. Let's say you're at home, going through your disaster preparedness kit, and you find a bottle of spring water you bought a long time ago in case of emergency. Checking by the cap, you see that the expiry date was a few months ago, and decide to use it to water plants or top off the washing machine instead of drinking it. Well, congratulations; you just wasted perfectly good water. Alright, 'perfectly good' might be an overstatement since we're still not sure what the microplastics floating around in there can do to us, and 'waste' is also a little harsh since plants are our friends too. But the point stands that you could have drank that water and it would have been more or less as good as the day you bought it. ▼ Consider drinking that bottle of water rather than keeping it outside to ward off stray cats as some people in Japan do. Image: Pakutaso This is because according to the Secretary General of the Japan Mineral Water Association, the 'expiration date' on bottled water isn't used for the same reason that it's used on perishable food. This is actually the date at which water inside the bottle is expected to have evaporated so much that the bottler cannot guarantee the amount written on the bottle is inside anymore and could be held liable for false labeling. Water bottles in Japan are usually made of a type of polyethylene terephthalate (PET), which is slightly permeable to water vapor. Some tests have found that when stored at around 25 degrees Celsius (77 degrees Fahrenheit) around two to three milliliters (0.07 – 0.1 ounces) of water vapor can escape per month. Also, in the hot summer months of around 37 degrees Celsius (99 degrees Fahrenheit), that rate goes up to about 4 milliliters per month. Meanwhile, the Measurement Act of Japan states that the actual contents of a bottle must be no less than two percent under the amount listed on the label for bottles under 500 milliliters (17 ounces) and no less than 10 milliliters less than the labeled amount for bottles 500 milliliters and up. So, bottlers of water simply calculate the rate of evaporation and release through the PET bottle, apply it to the legal threshold, and an expiry date is born, but it's not the water that expires. It's the label on the bottle that does. ▼ Phew… Honey, can you smell this label? I think it's gone bad. Of course, this is a separate subject from contamination from chemicals inside the plastic of the bottle, and it's possible both things could be occurring at the same time. But since evaporation happens rather quickly, would there even be enough time for significant amounts of potentially hazardous chemicals to seep into the water from the plastic? Going by the rate of evaporation found in studies, at two milliliters per month we can expect a 500-milliliter bottle to be empty in 20 years and 10 months. In the case of chemicals from the plastic entering the water, known as 'leaching,' the most worrisome elements are antimony and germanium. Under normal storage conditions, it would take about 71 years for enough antimony to enter the water to surpass Japanese safety standards and about 15 years for the germanium levels to surpass those deemed safe. Mind you these are just the standards, which tend to err on the side of caution, meaning one 15-year-old 500-milliliter bottle of water — wait… 140-milliliter at that point — probably won't send you straight to the ER. Even factoring in things like the lower concentration of water as it evaporates and the diminished leaching as the surface area shrinks, you're still looking at about a good nine years or so before standards are exceeded. One big caveat to all this is that it only applies to Japanese water that has been sterilized to Japanese standards and in bottles made to Japanese standards. Every country has its own standards, including what it considers the allowable limits of antimony and germanium to be, so do your own research before consuming 10-year-old bottles of water anywhere outside of Japan. Microplastics are also still a bit of a wildcard, in terms of their effect on the human body and how rapidly they break down in a typical Japanese PET bottle of water. Most microplastics are said to enter the water during bottling at the factory, so the bulk of it will already be present in a brand-new bottle anyway, with only a relatively moderate increase over time if stored securely. Unfortunately, there don't seem to be any studies on microplastic contamination over very long spans of time, such as 10 years. ▼ In other words, if you're worried about microplastics you really shouldn't even be drinking new plastic bottles of water. This information has recently been trending online in Japan and many came out in agreement with it, either using their own theoretical knowledge or personal experiences. Others still felt it wasn't worth the gamble. 'If the water can escape, can't things like bacteria get in?' 'Molecules like water and carbon dioxide are 0.3 nanometers, about the same as gaps in permeable plastic, but a virus is about 20 nanometers so it can't get in.' 'If I leave water out, I just use it for laundry.' 'I'm still just going to use it for cleaning and watering plants.' 'Water is always fine, isn't it?' 'I had some water that I'd been keeping for seven years in case of emergency. I drank it when I replaced it and it was fine.' 'I've been given expired ones before and there definitely seemed like less water inside.' 'If the bottles are breathable I probably shouldn't store them next to the toilet.' 'If the bottle is shriveled that's good because the air pressure outside is collapsing it. If the bottle is old and a normal shape, air has gotten inside and there might be bacteria too.' 'I'm still going to pour it down the drain anyway. Why take a chance?' Whether you're willing to crack open a seven-year-old bottle of Japanese water is entirely up to you, but the key takeaway from all this is that the expiration date written on it has absolutely nothing to do with its quality, so feel free to hang onto it at least a little bit longer than that. Source: Yahoo! Japan News, The Sankei Shimbun, withnews, Ministry of Economy Trade and Industry, Japan Soft Drink Association, Japanese Journal of Food Chemistry and Safety, Food Safety Commission, Hachima Kiko Images: ©SoraNews24 (unless otherwise noted) ● Want to hear about SoraNews24's latest articles as soon as they're published? Follow us on Facebook and Twitter!
Japan Today
5 days ago
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May was world's second-hottest on record, EU scientists say
A woman sunbathes at Retiro Park in Madrid, Spain, on May 31. By Kate Abnett The world experienced its second-warmest May since records began this year, a month in which climate change fueled a record-breaking heatwave in Greenland, scientists said on Wednesday. Last month was Earth's second-warmest May on record - exceeded only by May 2024 - rounding out the northern hemisphere's second-hottest March-May spring on record, the EU's Copernicus Climate Change Service (C3S) said in a monthly bulletin. Global surface temperatures last month averaged 1.4 degrees Celsius higher than in the 1850-1900 pre-industrial period, when humans began burning fossil fuels on an industrial scale, C3S said. That broke a run of extraordinary heat, in which 21 of the last 22 months had an average global temperature exceeding 1.5C above pre-industrial times - although scientists warned this break was unlikely to last. "Whilst this may offer a brief respite for the planet, we do expect the 1.5C threshold to be exceeded again in the near future due to the continued warming of the climate system," said C3S director Carlo Buontempo. The main cause of climate change is greenhouse gas emissions from burning fossil fuels. Last year was the planet's hottest on record. A separate study, published by the World Weather Attribution group of climate scientists on Wednesday, found that human-caused climate change made a record-breaking heatwave in Iceland and Greenland last month about 3C hotter than it otherwise would have been - contributing to a huge additional melting of Greenland's ice sheet. "Even cold-climate countries are experiencing unprecedented temperatures," said Sarah Kew, study co-author and researcher at the Royal Netherlands Meteorological Institute. The global threshold of 1.5C is the limit of warming which countries vowed under the Paris climate agreement to try to prevent, to avoid the worst consequences of warming. The world has not yet technically breached that target - which refers to an average global temperature of 1.5C over decades. However, some scientists have said it can no longer realistically be met, and have urged governments to cut CO2 emissions faster, to limit the overshoot and the fueling of extreme weather. C3S's records go back to 1940, and are cross-checked with global temperature records going back to 1850. © Thomson Reuters 2025.
