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).

In an era when deforestation and climate change threaten ecosystems worldwide, one man from Gujarat—a state on the west coast of India—is rewriting the narrative of environmental restoration.

Dr. Radhakrishnan Nair, fondly known as Nairji, has created 122 forests across India, transforming barren landscapes into thriving ecosystems. His most remarkable achievement, Smritivan (a memorial forest) in Gujarat—recognized as the world’s largest Miyawaki forest—stands as a testament to his vision. Spanning 470 acres and home to over 500,000 trees, this forest is not just a memorial but a beacon of ecological hope. Nair’s work demonstrates how one individual’s determination can combat global warming, restore biodiversity, and inspire communities to embrace a greener future.

From entrepreneur to green crusader

Born in Kasaragod, Kerala, R.K. Nair’s path to becoming India’s “Green Hero” was anything but conventional. After failing his 12th-grade exams, he took on a series of odd jobs, eventually rising to become a successful entrepreneur in the garment industry. But a pivotal moment came in 2011, in Umargam, Gujarat, when he witnessed the felling of 179 ancient trees for road construction. The cries of displaced birds and the destruction of their habitat struck a deep chord.

“I felt the birds were speaking to me,” Nair recalls. “That day, I vowed to create forests where no one would harm them.”

This epiphany led to the founding of Forest Creators with his friend Deepan Jain in 2014. Using corporate social responsibility (CSR) funds, Nair began planting trees—starting with 1,500 saplings on a single acre. Today, he has planted over 3.2 million trees across 12 Indian states—from Gujarat to Chhattisgarh, Rajasthan to Uttar Pradesh. His approach blends the Japanese Miyawaki method, known for rapid and dense forest growth, with a localized adaptation he calls Bharatavanam, tailored to India’s diverse ecosystems.

Smritivan: A green miracle in the Desert

Nair’s crowning achievement is Smritivan, a sprawling forest in Bhuj, Gujarat, established in memory of the 13,805 victims of the 2001 Gujarat earthquake. Originally conceived in 2004 but long stalled, the project gained new life when Nair took charge. Despite the 470-acre terrain being arid and hilly, he began planting in July 2021. “By August 2022, when Prime Minister Narendra Modi inaugurated the memorial, the forest had reached an astonishing 16 feet in height, with 223,555 saplings planted in the first phase alone. Today, Smritivan houses over 525,000 trees, with plans to add 40,000 more,” Nair says, in an interview with EdPublica.

A report from the Gujarat Ecology Commission, accessed by EdPublica, highlights Smritivan’s ecological transformation. Now home to 117 tree species, the forest supports 79 bird species, 28 types of butterflies, 21 reptiles, nine mammals, and two species of fish. The dense canopy and mulched soil prevent erosion, retain moisture, and enrich the land with organic matter. “With an 86% tree survival rate, species like neem and casuarina are flourishing,” according to the report published in 2023.

The forest has also led to localized temperature reductions, while its 50 check dams help replenish groundwater. A one-megawatt solar plant further bolsters its sustainability, making Smriti Van a global model of eco-restoration.

A report from the Gujarat Ecology Commission, accessed by EdPublica, highlights Smritivan’s ecological transformation. Now home to 117 tree species, the forest supports 79 bird species, 28 types of butterflies, 21 reptiles, nine mammals, and two species of fish

Industrialist Anand Mahindra recently shared a viral post on X, praising Nair for building the world’s largest Miyawaki forest.

Ecological impact: Restoring balance

Nair’s forests are more than green patches—they are ecological engines. “In Chhattisgarh, the coastal forest of 103,000 trees raised groundwater levels dramatically—from 160 feet to just 12 feet—reviving wells and sustaining communities,” Nair claims. Across India, his forests have restored biodiversity, attracted wildlife, and helped rebuild natural food chains.

The Gujarat Ecology Commission underscores Smriti Van’s role in carbon sequestration, a vital tool against climate change. Experts recommend ongoing assessments to quantify its carbon storage potential, which could significantly offset emissions.

Nair’s method ensures long-term ecological success. He doesn’t merely plant trees—he nurtures ecosystems. By selecting native species suited to local conditions, his forests are resilient and sustainable. They grow 10 times faster than natural forests, mimicking 150-year-old ecosystems in just 10–15 years. Dense planting (3–4 saplings per square meter) encourages vertical growth, mimicking natural competition for sunlight.

A Vision for the future

Nair’s ambition is bold: planting one billion trees by 2030. Backed by governments, corporations, and citizens, Forest Creators is scaling up to meet this audacious goal. His work has earned international acclaim, including an invitation to represent India at a NASA conference and a UNESCO Prix Versailles award for Smritivan.

Yet, Nair remains grounded—dressed in his signature white mundu, shirt, and cap—a nod to his Malayali roots and the spirit of India’s farmers.

Beyond ecology, Nair’s forests are also community spaces. Smriti Van has become a popular destination for its tranquil trails and vibrant festivals, with 94% of surveyed visitors citing its fresh air and peacefulness. Future plans include guided tours and educational programs to engage youth in environmental stewardship.

A Global inspiration

R.K. Nair’s story is a clarion call for individual action in the face of global crises. His 122 forests—especially the monumental Smritivan—showcase what one person’s vision and persistence can achieve. By restoring biodiversity, cooling urban climates, and sequestering carbon, Nair’s work supports global efforts to fight climate change. As he marches toward his billion-tree goal, he reminds us that a single seed, planted with purpose, can grow into a forest of change.

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.