Tokyo workers asked to swap suits for shorts to combat energy costs and heat

 

People on the Shibuya crossroad during an intense Tokyo heatwave in June last year. Photograph: Anadolu/Getty Images

by Justin McCurry in Tokyo

 

Public servants working for the Tokyo metropolitan government are being encouraged to swap their suits for shorts this summer to combat sweltering heat and rising energy costs caused by the US-Israel war on Iran.

Inspired by the country’s Cool Biz energy-saving initiative, Tokyo officials hope the measure will cut dependence on air conditioning.

Cool Biz, launched by the environment ministry in 2005, initially encouraged bureaucrats to dispense with ties and jackets, but has so far stopped short of allowing them to display their bare legs in front of colleagues.

Japan and other countries in Asia are growing anxious about the economic effects of the conflict in the Middle East, amid rising oil prices and shortages of petroleum products such as jet fuel.

 

Resource-poor Japan is particularly vulnerable to a prolonged war as it depends on the Middle East for 90% of its oil imports, most of which pass through the strait of Hormuz. About 20% of the natural gas used in South Korea comes via the same route.

Vietnam, South Korea and other countries have taken steps to ration energy use, while other Asian nations have encouraged government officials to work from home or reduced the length of the working week. In Seoul, authorities have urged residents to make short trips on foot or by bicycle.

 

Japan has already tapped into its large strategic oil reserves, with local media reporting on Friday that it plans to release a further 20 days’ worth from 1 May. It is also sourcing oil imports from suppliers that do not use the strait of Hormuz.

Experts have warned that if shipping in the vital waterway doesn’t return to normal soon, the world’s fourth-biggest economy will eventually face a crude oil shortage. That could force businesses and households to make more drastic cuts in petrol and electricity usage reminiscent of those introduced during the oil shocks of the 1970s.

The threat of an energy crunch had been “one of the factors” in allowing Tokyo government staff to wear casual clothes to work, Agence France-Presse said, adding that some employees had been spotted in shorts, T-shirts and short-sleeved blouses since the initiative’s launch this week to coincide with the start of Japan’s heatstroke warning system.

“I was a bit nervous, but it’s very comfortable, and I feel like it’ll improve my work efficiency,” a metropolitan government official who was wearing shorts to the office for the first time told the Yomiuri Shimbun newspaper. “As it gets even hotter, I’d like to come in earlier and work from home as well.”

Citing “a severe outlook for electricity supply and demand,” Tokyo’s governor, Yuriko Koike, who as environment minister was behind the Cool Biz campaign two decades ago, told reporters: “We encourage cool attire that prioritises comfort, including polo shirts, T-shirts and sneakers and – depending on job responsibilities – shorts”.

War notwithstanding, Japanese employers have been forced to rethink old rules on workplace attire as a result of the climate crisis. Last year, the country endured its hottest summer since records began in 1898, according to the meteorological agency.

Now that it is no longer unheard of for temperatures to rise to 40C or above, the agency last week announced a new extreme weather event: kokusho, or “cruelly hot”.

After 1,200 years, cherry blossom record to live on despite Japanese scientist’s death. Prof Yasuyuki Aono’s meticulous work charted shifting bloom dates as a marker of climate change

 

People viewing cherry blossoms in Osaka last week. Photograph: Jiji Press/EPA

by  Chris Baraniuk

 

Even in his final months, he counted the days until the cherry blossoms. Prof Yasuyuki Aono of Osaka Metropolitan University spent his career gathering data on the spring flowering dates of cherry trees in Japan in what is one of the world’s longest climate records tracking a seasonal occurrence.

Using sources dating as far back as the 9th century, he revealed that cherry tree flowerings have occurred progressively earlier in recent decades – a now famous marker of climate change.

 

Last April, Aono posted a photo to social media of his spreadsheet. He had just completed the 2025 entry, recording “4 [April]” as the peak flowering date for the particular cherry tree species he tracked, the mountain cherry, or Prunus jamasakura.

Below this, the next row was already marked “2026” but Aono never got to fill it in. He died on 5 August last year, according to former colleagues contacted by the Guardian.

Yasuyuki Aono learned old forms of Japanese so he could read 9th-century records. Photograph: Richard Primack

“You can very much see that he planned to continue,” said Tuna Acisu, a data scientist at Our World in Data, an online platform that publishes a chart based on Aono’s cherry tree data. “That made me a little bit emotional.”

Now, following a search launched by Acisu last week – sparked by fears that no one would be able to continue the 1,200-year cherry blossom record – a researcher in Japan has stepped forward and offered to make formal observations of the mountain cherry’s spring flowerings.

“He is consulting the same sources as Prof Aono to get us this year’s cherry blossom peak bloom and said he will confirm the date in the coming days,” Acisu said. The researcher in question asked to remain anonymous until the arrangement is finalised.

Acisu and colleagues first realised that something may have happened to Aono when they noticed in January that his university web page was no longer active. They then learned that he had died and that no other researcher or institution had emerged to carry on his observations. Spring arrived with no new mountain cherry data.

After Acisu launched her campaign to find a new cherry blossom observer, she received dozens of messages. “It’s really great to know that the dataset is being continued,” she said, expressing her gratitude to the new researcher. “I feel very relieved.”

 

Crucially, Acisu had sought a contact in Japan who could continue tracking not only the same species of cherry, but also in the same location: Arashiyama, Kyoto.

There are other projects that monitor cherry tree flowerings around Japan, since cherry bloom festivals are an important part of culture and tourism in the country, but not this specific species. For example, the Japan Weather Association monitors a different species: the Somei-yoshino cherry (Prunus x yedoensis), which was cultivated in the 19th century.

 

That Aono was able to compile flowering data for the mountain cherry over a period spanning more than 1,200 years is what gave his data series such significance, said Acisu.

Scientists have found the signature of climate change in a wide variety of other sources, including tree rings, plant pigments deposited in seabed sediments, and even temperature and humidity records jotted down by organ tuners in British churches.

Among the revelations made by Aono were the 2021 and 2023 peak flowering dates – they are the earliest in the entire mountain cherry record, occurring on the 85th and 84th day of those years, respectively.

Aono’s work on the mountain cherry was “extremely important”, said Toshio Katsuki, a dendrologist at the Forestry and Forest Products Research Institute in Ibaraki prefecture, who added that efforts to continue recording the same species’ spring flowering dates would be academically valuable.

Tourists wearing kimonos pose with cherry blossoms in Kyoto at the end of March this year. Photograph: Manami Yamada/Reuters

Richard Primack, a professor of biology at Boston University, met Aono on a trip to Japan in 2006. Aono told him that he had learned to read old forms of Japanese in order to build up his dataset of mountain cherry flowering dates. In dusty historical archives, Aono would find references to cherry blossom festivals in Kyoto and, from that, was able to calculate the flowering dates for specific years.

While some years are missing, the earliest record he found dated to 812. “It was really quite an amazing experience,” said Primack, remembering the meeting. “You just realise how dedicated an individual he was.”

In a paper published earlier this month, Primack and Katsuki described how flowering of the Somei-yoshino cherry also appears to be affected by climate change in southern areas of Japan. Data from 1965 to 2024 shows that milder winters were increasingly causing the spring-flowering cherries to have “a kind of bedraggled look, rather than a full, dazzling display,” said Primack. “Many of the flower buds were falling off without opening.”

Quiet adapting - Climate change is a verboten topic in the Trump administration. But that hasn’t stopped the US military from continuing to prepare for it.

 

Tyndall is being rebuilt as a super-resilient “installation of the future.”

Photographer: Patrick Focke/US Department of Defense via Digital

 

 By Amanda Kolson Hurley

 

 

When Hurricane Michael, a Category 5 storm, tore through Florida’s Tyndall Air Force Base in 2018, it battered F-22 stealth fighter jets, destroyed hundreds of buildings and churned up 700,000 cubic yards of debris. The total cost of the damage approached $5 billion.

Now, Tyndall is being rebuilt as a super-resilient “installation of the future.” New buildings sit more than a foot above the ground, to remain dry through 75 years of sea-level rise. Their roofs are designed to withstand winds of up to 165 miles per hour. Manmade oyster reefs will protect coasts by breaking up waves.

The massive project will be 70% complete next year, said the officer leading it, Col. Robert Bartlow, chief of the US Air Force Civil Engineer Center Natural Disaster Recovery Division. “This is a first for the Air Force,” he said, with large-scale, cutting-edge construction taking place “on top of an existing base, while there was a continued flying mission.”

 

Storms like Michael are becoming more powerful and damaging as the world warms, and many military installations are exposed to them and other climate hazards. Still, Secretary of Defense Pete Hegseth vowed last year that the Pentagon wouldn’t do any “climate change crap” on his watch. Biden-era climate action plans were scrapped, and the 2025 National Security Strategy invoked climate change only to label it a “disastrous” ideology. Hegseth canceled nearly 100 research studies related to global warming and security, which experts say will compound the loss of climate knowledge across the federal government under President Donald Trump.

“Because ‘climate’ is a dirty word, we’re not investing in that predictive capability,” said Sherri Goodman, secretary general of the non-governmental International Military Council on Climate and Security and, from 1993 to 2001, the US deputy undersecretary of defense for environmental security.

But as Tyndall shows, the Defense Department is still engaged on one front of the climate fight: steeling its bases against the effects of a warming atmosphere, such as higher seas, fiercer storms and deadlier fires. A new flood wall is rising at the US Naval Academy in Maryland; a low-lying Air Force runway is being elevated in Virginia; and projects are underway to reduce wildfire risk around various military sites in Hawaii.

Work that was previously described as confronting the climate threat is now touted for ensuring “resilience” and “readiness.” The semantics are a nod to necessity: At stake are hundreds of billions of dollars of assets and the ability to launch missions quickly and smoothly.

Much of the military’s resilience work began years ago; construction timelines are long. The $900 billion 2026 National Defense Authorization Act, which Trump signed into law in December, includes measures that could be said to come under the umbrella of climate adaptation. The law bolsters the military’s ability to respond to wildfires; raises the cost limit for replacing structures destroyed by disasters; and requires military leaders to identify the biggest risks to water security on bases.

Close to $400 billion of federal government assets, most of them belonging to the Defense Department, are at high risk of being hit by a major coastal flood or storm in coming years, according to a Bloomberg Law analysis.

The Pentagon explicitly recognized the warming climate as a danger for many years. The 2008 National Defense Strategy flagged climate change as an emerging risk, and two years later it was named a national security threat in the Pentagon’s Quadrennial Defense Review. After that, the Defense Department and the individual armed forces put out a stream of climate and sustainability plans. (Some have now been removed from government websites.)

James Mattis, who served as defense secretary during President Donald Trump’s first term, described climate change as a destabilizing force in 2017. His Biden-era successor Lloyd Austin said in 2021, “We face all kinds of threats in our line of work, but few of them truly deserve to be called existential. The climate crisis does.”

Trump and Hegseth have made a sharp pivot. In a March 2025 memo to military leaders, Hegseth called climate change a “distraction” from fighting wars, ordered that references to it be removed from mission statements and barred any environmental initiatives from being included in the Future Years Defense Program, a strategic plan.

Hegseth also included a caveat big enough to steer an aircraft carrier through. “Nothing in this memorandum,” he wrote, “shall be construed to prevent the department from assessing weather-related impacts on operations, mitigating weather-related risks, conducting environmental assessments, as appropriate, and improving the resilience of military installations.”

The overarching goal at Tyndall, Bartlow said, is “preserving lethality in a high-end combat capability. When we talk about resilience, it’s focused on preserving that combat capability.” If another Category 5 hurricane hits, “there’ll be some interruptions, but the idea is you’ll be able to recover this installation quickly,” hesaid. “You can make that direct link back to readiness.”

Critical Atlantic current significantly more likely to collapse than thought. Scientists say finding is ‘very concerning’ as collapse would be catastrophic for Europe, Africa and the Americas

The Atlantic meridional overturning circulation is a major part of global climate system and is known to be at its weakest for 1,600 years as a result of climate crisis. Photograph: Henrik Egede-Lassen/Zoomedia/PA

by  Damian Carrington Environment editor

 

The critical Atlantic current system appears significantly more likely to collapse than previously thought after new research found that climate models predicting the biggest slowdown are the most realistic. Scientists called the new finding “very concerning” as a collapse would have catastrophic consequences for Europe, Africa and the Americas.

The Atlantic meridional overturning circulation (Amoc) is a major part of the global climate system and was already known to be at its weakest for 1,600 years as a result of the climate crisis. Scientists spotted warning signs of a tipping point in 2021 and know that the Amoc has collapsed in the Earth’s past.

Climate scientists use dozens of different computer models to assess the future climate. However, for the complex Amoc system, these produce widely varying results, ranging from some that indicate no further slowdown by 2100 to those suggesting a huge deceleration of about 65%, even when carbon emissions from fossil fuel burning are gradually cut to net zero.

 

The research combined real-world ocean observations with the models to determine the most reliable, and this hugely reduced the spread of uncertainty. They found an estimated slowdown of 42% to 58% in 2100, a level almost certain to end in collapse.

The Amoc is a major part of the global climate system and brings sun-warmed tropical water to Europe and the Arctic, where it cools and sinks to form a deep return current. A collapse would shift the tropical rainfall belt on which many millions of people rely to grow their food, plunge western Europe into extreme cold winters and summer droughts, and add 50-100cm to already rising sea levels around the Atlantic.

Dr Valentin Portmann, at the Inria Centre de recherche Bordeaux Sud-Ouest in France and who led the new research, said: “We found that the Amoc is going to decline more than expected compared to the average of all climate models. This means we have an Amoc that is closer to a tipping point.”

Prof Stefan Rahmstorf, at the Potsdam Institute for Climate Impact Research in Germany, said: “This is an important and very concerning result. It shows that the ‘pessimistic’ models, which show a strong weakening of the Amoc by 2100, are, unfortunately, the realistic ones, in that they agree better with observational data.”

He added: “I now am increasingly worried that we may well pass that Amoc shutdown tipping point, where it becomes inevitable, in the middle of this century, which is quite close.”

Rahmstorf, who has studied the Amoc for 35 years, has said a collapse must be avoided “at all costs”. “I argued this when we thought the chance of an Amoc shutdown was maybe 5%, and even then we were saying that risk is too high, given the massive impacts. Now it looks like it’s more than 50%. The most dramatic and drastic climate changes we see in the last 100,000 years of Earth history have been when the Amoc switched to a different state.”

 

The Amoc is slowing because air temperatures are rising rapidly in the Arctic because of global heating. That means the ocean cools more slowly there. Warmer water is less dense and therefore sinks into the depths more slowly. This slowing allows more rainfall to accumulate in the salty surface waters, also making it less dense, and further slowing the sinking and forming an Amoc feedback loop.

The Amoc system is highly complex and subject to random natural variations, making precise predictions impossible. However, a major weakening is now expected by scientists and that alone could have serious impacts in the decades to come.

The new research, published in the journal Science Advances, explored four different ways of using real-world observations to assess the models. They found a method called ridge regression, which had been little used in climate science before now, provided the best results.

The Amoc is difficult to model because it is governed by subtle differences in water density caused by salinity changes over the entire Atlantic. The reduction in uncertainty in the new analysis results from identifying the models that better reflect surface salinity in the south Atlantic, which scientists already knew was important. This makes the work “very credible”, said Rahmstorf.

Rahmstorf said Amoc slowdown in 2100 may be even greater than in the new, pessimistic assessment. This is because the computer models do not include the meltwater from the Greenland ice cap that is also freshening the ocean waters: “That is one additional factor that means the reality is probably still worse.”

US had hottest March on record as nation faced ‘unprecedented’ heat. The continental US registered its most abnormally hot month in 132 years of records, according to Noaa data

 

A person wears a hat while walking along the Strand in Redondo Beach, California, on 20 March 2026, during a heatwave. Photograph: Patrick T Fallon/AFP/Getty Images

 Associated Press

March’s persistent unseasonable heat was so intense that the continental United States registered its most abnormally hot month in 132 years of records, according to federal weather data. And the next year or so looks to turn the dial up on global warmth even more, as some forecasts predict a brewing El Niño will reach super strength.

Not only was it the hottest March on record for the US but the amount it was above normal beat any other month in history for the lower 48 states. March’s average temperature of 50.85F(10.47C) was 9.35F (5.19C) above the 20th-century normal for March.

That easily passed the old record of 8.9F set in March 2012 as the most abnormally hot month on record – regardless of the month of the year – according to records released on Wednesday by the National Oceanic and Atmospheric Administration (Noaa).

 

The average maximum temperature for March was especially high at 11.4F above the 20th-century average and was almost a degree warmer than the average daytime high for April, Noaa said.

Six of the nation’s top 10 most abnormally hot months have been in the last 10 years. This February, which was 6.57F above 20th-century normal, was the 10th highest above normal.

“What we experienced in March across the United States was unprecedented,” said Shel Winkley, a meteorologist with Climate Central, a non-profit science research group.

“One reason that’s so concerning is just the sheer volume of records, all-time records that were set and broken during that time period,” Winkley said. “But also this is coming on the heels of what was the worst snow year. And the hottest winter of record.”

April 2025 to March 2026 was the warmest 12-month period on record in the continental United States, according to Noaa.

On 20 and 21 March, about one-third of the nation felt unseasonable heat that would have been virtually impossible without human-caused climate change, Climate Central calculated.

More than 19,800 daily temperature records were broken for heat across the country, according to meteorologist Guy Walton, who analyzes Noaa data. More than 2,000 places set monthly records for heat – harder to break than daily records – Walton calculated. That’s more March heat records set just last month than in entire decades in the past.

All those broken records “tells us that climate change is kicking our butts”, said Jeff Masters, a Yale Climate Connections meteorologist.

“January through March period was the driest on record for the contiguous US. So not only was it hot, it was record dry as well,” Masters said. “And that’s a bad combination for water availability, for agriculture, for river levels, for navigation.”

The European climate and weather service Copernicus and Noaa are both forecasting a “super” strong El Niño to form in a few months and intensify into the winter.

“A strong El Niño could plausibly push global temperatures to new record levels in late 2026 and into 2027,” Victor Gensini, a Northern Illinois University meteorology professor, said.

Arctic sea ice just dropped to an alarming new low

 

Arctic sea ice has reached a record winter low this year. Photographer: Michael Runkel/imageBROKER/Alamy/File

 

By Laura Paddison

 

Right now, the Arctic is maxing out on sea ice – the cold of winter has built up over months of darkness, and ice has spread as far south as it will all year. It’s the North Pole’s sea ice maximum, except this year, it’s alarmingly low.

There is roughly half a million square miles of ice missing in this year’s “max,” compared to average — an amount twice the size of Texas.

It’s the latest profoundly worrying signal from the top of the planet, a region which has become a clear victim of the climate crisis as humans burn fossil fuels, and increasingly a geopolitical hotspot as melting ice opens up commercial and military opportunities.

Winter is when Arctic ice builds up, typically reaching its maximum extent in March. This year, when scientists from NASA and the National Snow and Ice Data Center measured it on March 15, they found the ice had reached 5.52 million square miles — roughly 9% lower than the average between 1981 and 2010. 

 

It came in just below last year’s record maximum of 5.53 million square miles, but close enough to it that it’s technically a tie, and is the lowest peak observed since satellite records began in 1979.

“A low year or two don’t necessarily mean much by themselves,” said Walt Meier, a NSIDC ice scientist, but when looked at in the context of a multi-decade downward trajectory, “it reinforces the dramatic change to Arctic sea ice throughout all seasons.”

Scientists are concerned about what it will mean for the spring and summer melt season. The last 19 years have seen the lowest sea ice levels on record.

The Arctic will be ice-free in the summer at some point by 2050, even if humans stop pumping out climate pollution, according to a 2023 study. 

 

Disappearing sea ice has global impacts. Ice acts like a giant mirror, reflecting the sunlight away from the Earth and back into space. As it shrinks, more of the sun’s energy is absorbed by the dark ocean, which accelerates global heating.

This new record is not a surprise as Arctic sea ice had been running at near record lows all winter, said Jennifer Francis, a senior scientist at Woodwell Climate Research Center. But it’s one more alarm bell.

“Like when a person’s blood pressure is out of whack signaling a health problem, the ongoing loss of sea ice is yet another symptom indicating the Earth’s climate is in big trouble,” she said.

The cause is no mystery she added, “the ongoing buildup of heat-trapping gases in the atmosphere from burning fossil fuels is warming the oceans, heating the air, melting the ice, and worsening weather extremes all around the world.”

Record high ocean temperatures off southern California raise fears of prolonged marine heatwave

The waters of southern California historically warm every few years. But the marine heatwave that started last fall wasn’t caused by tropical currents. Photograph: Kevin Carter/Getty Images

by  Roque Planas

 Researchers warn the high-pressure conditions could disrupt marine life and ecosystems if it continues

For more than a century, shoreline stations operated by the Scripps Institution of Oceanography have measured water temperatures along the California coast. This year, they are flashing a warning sign.

Over the last three months, several stations have repeatedly posted record-breaking daily high temperatures – with the La Jolla station registering temperatures a full 10F above historical average at one point last month.

The waters of southern California historically warm every few years as tropical currents make their way north, a phenomenon known as El Niño. But the marine heatwave that started last fall wasn’t caused by tropical currents. Instead, a high-pressure atmospheric system – think of calm, sunny days – has perched above southern California, warming both air and sea above historic levels. The same phenomenon has helped fuel a ferocious California heatwave on land.

 

The extended ocean warming has drawn comparisons to “the Blob”, a three-year marine heatwave caused by similar prolonged high-pressure conditions a decade ago that devastated marine life. The next few weeks are likely to determine whether this marine heatwave fizzles out or evolves into something more Blob-like, scientists say.

“The biggest concern is how the year plays out,” Andrew Leising, an oceanographer with the National Oceanic and Atmospheric Administration, said. “We could be looking at much larger impacts next fall and winter, if it stays warm and then it’s followed by a strong El Niño.”

 

It’s typical in the spring for shifting atmospheric conditions to generate north-westerly winds that push warm surface water back out to the open ocean, allowing cooler water from below to rise to the surface – a phenomenon called upwelling. Upwelling brings nutrient-rich water from the depths to the surface, feeding the phytoplankton that play a crucial role in supporting much of California’s marine life.

Over the last few days, high water temperatures have cooled somewhat, raising the prospect that the heatwave may be dissipating already. It will take more time, however, to know for sure that the heat is clearing.

“The expectation right now is that likely the waters down to even southern California should start cooling a little bit into next month, but it’s not a guaranteed thing,” Leising said. “The concern is the sequence of events and how they unfold.”

Prolonged ocean heat has a devastating impact on phytoplankton and can cause harmful algal blooms. Those changes can wreak havoc on many forms of marine life, from sea lions and dolphins, to shore birds and halibut. The Blob years led to one of the worst Dungeness crab seasons in recent history, said Melissa Carter, a researcher at the UC-San Diego Scripps Institution of Oceanography.

Such heatwaves are becoming more common and lasting longer, partly because of the slow warming of the oceans driven by the climate crisis, and partly because of atmospheric changes that scientists are still struggling to understand.

“The question is what’s causing us to have these extreme warm temperatures?” Carter said. “What are the drivers? That’s what we’re trying to find out.”

 

What concerns Carter is that once these high-pressure systems establish themselves in an area, they create a “feedback loop” that tends to reinforce warm, calm conditions, making upwelling less likely to occur, she said.

“If these systems do become that strong and persistent, where they come every year, it can have the potential to shut down upwelling,” Carter said. “Everything we think of related to the health of the ecosystems of the west coast could be forever altered.”

The lingering ocean heat offers a few upsides, though they pale in comparison with the costs. The warmer water temperatures bring tuna far closer to shore, making it easier to fish for them. Surfers and swimmers have also enjoyed warmer water through the winter.

“I enjoy being in the water when it’s a marine heatwave,” Carter said. “But our ocean should not be a swimming pool. Nothing can live in a swimming pool. That’s not what we want.”