Author: Derrick Lester

The deep, wind-driven cold of the open ocean in midwinter, when the water’s surface temperature is only a few degrees above freezing and the wind across it removes heat quickly enough to produce visible steam rising from wave crests, is what the North Atlantic experiences in January at about 60 degrees north latitude. This is not the static cold of high altitudes. One of the most significant physical processes in the global climate system takes place here: warm, salty water that has moved north from the tropics cools at the surface until it becomes dense enough to sink, sliding down…

You can see what dredging machinery and years of massive clam harvesting have left behind at low tide on Scarborough Shoal, when the water lowers sufficiently to reveal the upper borders of what was once a reef shelf. The coral formations that make the Spratly and Paracel archipelagos one of the world’s most biodiverse reef systems—equivalent to the Amazon basin in terms of species density in terms of ecological richness—remain in much reduced form throughout a sizable portion of the South China Sea. Meters of sand blasted up from the nearby reef cover the seafloor beneath China’s man-made islands in…

Climate experts had been reading and rereading a report that was published in Nature before the end of 2018. Laure Resplandy, a researcher at Princeton University’s Department of Geosciences, was the primary author. The findings were so striking that they deviated from the typical incremental contributions to the literature on ocean heat. Her team’s findings revealed that the world’s oceans were absorbing almost 60% more heat each year than earlier UN climate predictions had indicated. Not a small change. a significant discrepancy between the findings of an independent measurement approach and what the models and reporting frameworks had been telling…

A crew from Kraken Robotics has been testing equipment that most people would never see and wouldn’t immediately identify if they did, at a harbor in Newfoundland where the water is consistently chilly enough to make you consider how long you’d endure if something went wrong. The KATFISH sonar system creates images of the seafloor that resemble aerial photography rather than sonar data. It is towed behind an unmanned surface vessel that moves across the surface while the sensor body runs below on a cable. A traditional sonar system would return a blurry smear, but the KATFISH system produces clear,…

A few years ago, a senior executive from a deep-sea mining company gave a presentation in a conference room at a mining industry event in London. The presentation began with pictures of Indonesian open-pit nickel mines, with red laterite soil scraped to the horizon, an orange river flowing downstream, and communities forced off their land to make way for extraction. Then he clicked to a different picture of the deep ocean, which was dark and seemed to be featureless, displaying nothing but a huge, peaceful body of water. The argument was the contrast. He asked, “Would you prefer this or…

Something that shouldn’t be there gets pulled up by a fisherman in August when he is carrying traps off the coast of Maine. Not a lobster, which are becoming more difficult to locate in the shallower inshore seas where they were formerly dependable. He pulls up a fat, hostile blue crab that you would expect in the Carolinas or the Chesapeake Bay, not this far north. He tosses it back, notes it in his manner of noting things (not on paper, but in the area of his memory dedicated to things that are evolving), and continues working. A few miles…

A Pacific footballfish, a rare and unusual species with a globular body, fang-like teeth, and a long filament extending from its head with a bulbous, lighted tip, washed up on a San Diego beach in early 2023. People took pictures of it and shared them online, and the response was predictable: fascination combined with something that deep-sea fish sometimes create but is difficult to pinpoint. The animal resembles something put together from disparate parts rather than a fish since it is designed for a setting so dissimilar from the surface world. Most people initially spotted the light at the end…

A few hundred meters below the surface, there is a region in the Eastern Tropical Pacific where oxygen runs out. Not entirely, not to the point of total anoxia, but low enough that the microorganisms carrying out their regular tasks in the water column switch to alternative metabolic pathways, using nitrate rather than oxygen to decompose organic matter. Nitrous oxide is a result of that process. Over time, it builds up in these oxygen minimum zones, accumulating in the cold, dark water where the gas has nowhere to go until it is forced toward the surface. There’s an upwelling. The…

There are polymetallic nodules on the bottom in the Pacific Ocean somewhere in the Clarion-Clipperton Zone, an approximately 4.5 million square kilometer length of abyssal plain between Hawaii and Mexico. No one has yet discovered a commercially feasible method to gather these nodules at scale. There are nodules. They contain actual, verified manganese, cobalt, nickel, and copper. Despite decades of exploratory permits and hundreds of millions of dollars spent, a profitable mining operation has yet to emerge. As of 2026, the commercial case for deep-sea mining is still a forecast rather than an established reality. Nevertheless, the projects go on,…

When you drive along the Louisiana Gulf Coast on a summer afternoon, you pass an environment that was once much larger than it is now, past the marinas, fish camps, and rusted signs advertising shrimp boats for charter. The vast, fertile, esthetically nondescript but biologically significant wetlands that originally stretched miles inland from the shoreline have been disappearing for decades. The marshes have been simultaneously being eaten away by subsidence, sea level rise, and the channelization of the Mississippi River, which used to replenish them with sediment. The remaining material holds, absorbs, and filters less than it did during the…