“Ongoing efforts to enhance the self-sustainability and biodiversity of the Han River ecosystem are yielding substantial results, the Seoul Metropolitan Government said Monday…

Since 2007, the number of trees along the Han River has doubled, with the total now reaching 3.65 million. Additionally, the diversity of species in the area has surged by nearly 30 percent, reflecting a healthier ecosystem.”

From The Korea Times.

“Frontier has facilitated offtake agreements with CarbonRun, a Canadian company using a well-established method of river de-acidification called river liming for carbon removal. Frontier buyers will pay $25.4 million to permanently remove 55,442 tons of CO₂ between 2025 and 2029 at multiple sites, starting with deployments in Nova Scotia, Canada. This is the first carbon removal offtake via river liming.

River liming adds crushed up limestone (alkalinity) to acidified rivers to repair the damage caused by acid rain. It was successful in treating the acid rain problem in Scandinavia. Due to increased costs, the practice is in a state of decline, with many applicable regions having to cease or reduce river liming activities. CarbonRun discovered that adding limestone also boosts rivers’ natural ability to extract CO₂ from the air. The atmospheric and land-based carbon found in rivers combines with the limestone to produce bicarbonate. Bicarbonate in the river water makes its way to the open ocean for permanent storage.

The Frontier offtake focuses on rivers acidified by pollution and climate change, where river liming has both carbon removal and ecosystem benefits such as salmon and shellfish population restoration. Expanding river liming to pH-neutral rivers would give this approach the potential to reach gigaton scale.”

From Frontier.

“At the time of writing, Make Sunsets has deployed 82 balloons, offsetting the warming caused by 53,800 tons of CO2 (the world emits about 37 billion tons of CO2 annually). It has more than 500 customers, including Casey Handmer, founder and CEO of Terraform Industries, a startup using tech to create natural gas from sunlight and air.”

From Freethink.

“Since at least the 1970s, electrochemists have cast their gazes upon the world’s vast, briny seas and wondered how they could harness the endless supply of hydrogen locked within. Though it was technically possible to grab the hydrogen by running an electrical current through the water, the reaction turned the salt in the water into the toxic and corrosive gas chlorine, which made commercializing such a process challenging.

But last year, a startup called Equatic made a breakthrough that not only solves the chlorine problem, but has the potential to deliver a two-for-one solution: commercial hydrogen production and carbon removal. With funding from the Department of Energy’s Advanced Research Projects Agency-Energy, or ARPA-E, the company moved swiftly to scale its innovation, called an “oxygen-selective anode,” from the lab to the factory. On Thursday, it announced it had started manufacturing the anodes at a facility in San Diego.”

From Heatmap.