The accelerating disappearance of the world’s glaciers—often called the “water towers” of our planet—is now a full-blown global emergency, warned experts and leaders gathered in Tajikistan for the International Conference on Glaciers’ Preservation. Underway in Dushanbe from 29 May to 1 June in Dushanbe, the event has brought together heads of state, UN officials, scientists, and development partners in a clarion call to put glacier protection at the top of the global climate agenda.

“Glaciers preservation is not just a problem of countries with glaciers but rather a global crisis that deserves the immediate attention of the international community,” said Tajikistan’s President Emomali Rahmon in his opening address.

The urgency is clear. According to a statement issued by the World Meteorological Organization (WMO), five of the past six years have seen the most rapid glacier retreat on record. Glaciers are now the second largest contributor to sea-level rise after ocean warming.

“Our glaciers are dying,” said WMO Secretary-General Celeste Saulo. “The death of a glacier means much more than the loss of ice. It is a mortal blow to our ecosystems, economies, and social fabric.”

Recent disasters highlight the stakes. Just this week, a glacier collapse in the Swiss Alps unleashed a torrent of ice and debris that buried parts of the village of Blatten. Early warnings prevented fatalities—but many developing nations lack such systems. “We need to bridge science and services, and forecasts and action,” Saulo urged.

The conference will culminate in the release of the Dushanbe Glaciers Declaration, a strategic document outlining commitments and partnerships to be presented at COP30 in Brazil later this year. It is a key milestone in the International Year of Glaciers’ Preservation.

UN Deputy Secretary-General Amina Mohammed cited devastating findings from the WMO’s latest climate report. “2021 to 2024 represents the most negative three-year glacier mass balance period on record,” she said, pointing out that glaciers have lost over 9,000 billion tons of ice since 1975—equivalent to an ice block the size of Germany, 25 meters thick.

Glaciers currently store about 70% of the world’s freshwater. Their meltwater sustains hundreds of millions downstream during the dry season. But that lifeline is fading. In the Himalayas, a 2023 report from the International Centre for Integrated Mountain Development (ICIMOD) warned that the region could lose up to two-thirds of its glaciers by 2100. Tajikistan alone has lost nearly 30% of its glaciers over the last century.

The Vanj Yakh Glacier (formerly Fedchenko), the largest continental glacier, has retreated by over 1 km and shrunk by 44 km²—enough to fill 6.4 million Olympic swimming pools.

“Melting glaciers threaten lives on an unprecedented scale – including the livelihoods of more than 2 billion people in Asia alone,” said Asian Development Bank Vice-President Yingming Yang. “ADB is committed to helping the region adapt and transition to clean energy without compromising development.”

UNESCO Director-General Audrey Azoulay highlighted the cultural and ecological loss as well. “In 2022, a UNESCO study found that glaciers in one third of world heritage sites are projected to disappear by 2050,” she said. “It is a stark reminder of the need for bold and immediate climate action.”

Key conference themes include scientific monitoring, water cooperation, and adaptation investment. The message is clear: the world cannot afford to lose its glaciers—or the freshwater, stability, and security they provide.

As Celeste Saulo put it: “Observing, predicting, and effectively communicating glacier changes are vital to mitigating their impacts on people, economies, and ecosystems.”

Scientists at MIT and the Woods Hole Oceanographic Institution (WHOI) have developed a novel imaging technique that effectively “removes” water from underwater scenes, revealing the true colours of marine environments. The new tool, called SeaSplat, corrects for optical distortions like light scattering and colour fading, offering marine biologists a powerful new way to explore and monitor ocean ecosystems.

“One dream of underwater robotic vision that we have is: Imagine if you could remove all the water in the ocean. What would you see?” said John Leonard, MIT professor of mechanical engineering, in a media statement.

Traditionally, capturing the real appearance of underwater scenes has been difficult due to two main challenges: backscatter, which creates a cloudy haze by reflecting light off tiny ocean particles, and attenuation, which causes certain colors to fade with distance. SeaSplat overcomes both by analyzing how each pixel in an image is affected and correcting for those effects.

“With SeaSplat, it can model explicitly what the water is doing, and as a result it can in some ways remove the water, and produces better 3D models of an underwater scene,” said Daniel Yang, an MIT graduate student and co-developer of the tool.

SeaSplat combines a colour-correcting algorithm with a 3D imaging technique known as 3D Gaussian Splatting (3DGS) to generate immersive, high-fidelity, virtual environments from underwater photographs. The results are detailed three-dimensional models that retain accurate color no matter the viewing angle or distance.

The researchers tested SeaSplat using imagery from a variety of ocean locations, including the Caribbean, the Red Sea, the Pacific near Panama, and the U.S. Virgin Islands. In each case, SeaSplat produced vivid, true-color 3D environments that could be virtually navigated.

“Once it generates a 3D model, a scientist can just ‘swim’ through the model as though they are scuba-diving, and look at things in high detail, with real color,” Yang said in the statement.

Marine scientists could soon use this technology to monitor sensitive environments such as coral reefs. Traditional cameras often misrepresent signs of distress like coral bleaching, but SeaSplat’s color-accurate imaging could change that.

“Bleaching looks white from close up, but could appear blue and hazy from far away, and you might not be able to detect it,” noted Yogesh Girdhar, a WHOI associate scientist. “Coral bleaching, and different coral species, could be easier to detect with SeaSplat imagery, to get the true colors in the ocean.”

Although the current version of SeaSplat requires significant computing power and is too bulky to run onboard an autonomous underwater vehicle, it is well-suited for tethered operations where data can be transmitted to a ship-based computer in real time.

“This is the first approach that can very quickly build high-quality 3D models with accurate colors, underwater, and it can create them and render them fast,” Girdhar said. “That will help to quantify biodiversity, and assess the health of coral reef and other marine communities.”

Yang, Girdhar, and Leonard will present their work at the IEEE International Conference on Robotics and Automation (ICRA).

A new study led by researchers from MIT, Georgia Tech, and other institutions suggests that the use of marine scrubbers—devices that clean sulfur emissions from exhaust gases—may be just as environmentally friendly, if not more so, than burning low-sulfur fuels. This groundbreaking research, published in Environmental Science and Technology, challenges the common assumptions about the environmental impact of scrubbers and has important implications for the future of the maritime industry.

The 2020 mandate by the International Maritime Organization (IMO) to cap the sulfur content of marine fuels at 0.5% pushed shipping companies to consider alternatives to the traditionally used heavy fuel oil (HFO), which contains much higher levels of sulfur. The options? Companies could either burn low-sulfur fossil fuels, install exhaust gas cleaning systems (scrubbers), or switch to biofuels. While the latter has been limited by availability, scrubbers became the go-to solution for many, thanks to their cost-effectiveness and ability to enable continued use of cheaper, high-sulfur fuels.

However, a critical question remained: How “green” are scrubbers when viewed through a holistic environmental lens?

“Scrubbers Turned Out to Be an Unexpectedly Deep and Important Transitional Issue”

According to Neil Gershenfeld, MIT professor and senior author of the study, the study explored this question through a comprehensive lifecycle assessment. “In our collaboration with Oldendorff Carriers to broadly explore reducing the environmental impact of shipping, this study of scrubbers turned out to be an unexpectedly deep and important transitional issue,” he explained.

The Study: A Comprehensive “Well-to-Wake” Assessment

The researchers used a “well-to-wake” approach, which examines the environmental impact of fuels and technologies from production to final use. They looked at everything from the manufacturing and transportation of fuels to their emissions when burned on ships. They also gathered data directly from a bulk carrier vessel in China that burns heavy fuel oil with a scrubber and low-sulfur fuel under similar conditions. The team analyzed emissions from the exhaust and samples of washwater discharged from the scrubbers, which is often a concern due to its potential toxicity.

Lead author Patricia Stathatou, an assistant professor at Georgia Tech, emphasized that a full lifecycle analysis is critical for understanding the true environmental impact. “If we just look at everything that happens before the fuel is bunkered onboard the vessel, heavy fuel oil is significantly more low-impact, environmentally, than low-sulfur fuels,” Stathatou said. She added that scrubbers, with a lifetime of about 20 years, have a minimal environmental footprint compared to the energy-intensive production of low-sulfur fuels.

Surprising Findings: Scrubbers Surpass Low-Sulfur Fuels in Several Areas

The results of the study were surprising. When the researchers considered the entire lifecycle, including the production of fuels and scrubbers, burning heavy fuel oil with scrubbers was found to be the least harmful option in terms of most environmental factors, such as greenhouse gas emissions, terrestrial acidification, and ozone formation.

“The claims about environmental hazards and policies to mitigate them should be backed by science,” said Stathatou. “You need to see the data, be objective, and design studies that take into account the full picture to be able to compare different options from an apples-to-apples perspective.”

Scrubbers: A Proven and Mature Technology

Marine scrubbers, which have been used for decades in land-based applications like power plants, are now widely deployed in the shipping industry. Scrubbers are typically large vertical tanks that use seawater to wash sulfur dioxide from the exhaust gases. The seawater reacts with the sulfur, converting it into sulfates, which are environmentally benign. The washwater is then released back into the ocean, where it is diluted by the vast expanse of seawater.

Despite concerns over the acidity and potential pollutants in the washwater, the study found that most chemical concentrations in the washwater were well below the limits set by environmental regulations, such as those from the U.S. Environmental Protection Agency and the European Union.

Scrubbers Meet International Standards

The researchers also tested the washwater for over 60 chemical parameters, including metals and hydrocarbons, and found that concentrations of harmful substances were generally well within safe levels. “Scrubbers reduce sulfur dioxide emissions by 97 percent, making them just as effective as low-sulfur fuels in terms of sulfur emissions,” said Scott Bergeron, managing director of Oldendorff Carriers, who co-authored the study.

A Call for Balanced Environmental Policies

This research has significant implications for future maritime environmental policies. As Stathatou points out, there is growing momentum toward alternative fuels, but it’s critical to assess the environmental impacts of these fuels in comparison to current technologies. “We must do our due diligence to compare them equally with existing solutions to see the costs and benefits,” she said.

The study’s findings could reshape policies governing the maritime industry, suggesting that scrubbers may offer a more sustainable path forward than previously thought. The research team hopes this will prompt a more science-driven approach to reducing shipping’s environmental footprint.

The study, which includes contributions from researchers at MIT, Georgia Tech, and Oldendorff Carriers, highlights the importance of scientific analysis in shaping policies that reduce the environmental impact of global shipping. With over 5,800 vessels now using scrubbers worldwide, the technology is clearly making an impact, but questions around its long-term environmental effects are only just beginning to be answered.