The Southern Ocean surrounding Antarctica is the newest ocean, not geologically but in terms of recognition by the National Geographic Society, which didn't recognize the Southern Ocean as a distinct body of water until 2021. For most of 37 years, since calving off the Filchner Ice Shelf, an enormous iceberg has been stuck in a patch of shallow water in the Southern Ocean. This so-called "megaberg," which is described as 1300 feet tall and the area of Rhode Island (or 3x the area of NYC, or with a diameter twice the distance from downtown Washington, DC, to downtown Baltimore) is now on the move and is expected to cross from the Southern Ocean into the South Atlantic in the coming weeks or months, depending on currents and wind speeds. www.washingtonpost.com/weather/2023/12/06/mega-iceberg-antarctica/
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This map highlights deep-sea mining rights, which are emerging as a new frontier in geopolitical contestation over rare-earth metals. The Clarion-Clipperton Zone between Mexico and Hawaii, for example, is believed to contain up to 6x the cobalt and 3x the nickel of all land-based deposits. (Map from www.washingtonpost.com/world/interactive/2023/china-deep-sea-mining-military-renewable-energy/.)
For those looking for something to read that combines adventure, science, and geography, Science News reviews The Deepest Map, a new book by journalist Laura Trethewey about "the high-stakes race to chart the world's oceans": www.sciencenews.org/article/deepest-map-chart-ocean-earth
This map, from The Wall Street Journal, shows global ocean temperatures from mid-July to mid-August as compared with historical averages (red=hotter, blue=colder). The map is used in the context of an article discussing how warming oceans and migrating sea life are forcing changes in fishing and allied industries (from www.wsj.com/us-news/climate-environment/heating-waters-force-change-in-industries-that-depend-on-the-ocean-efd471d6).
If you're thinking about an exotic fall getaway, September and October are usually the peak months for the Maldives' bioluminescent beaches. Vaadhoo Island at the northern end of the archipelago is the best known spot to see the "sea of stars," but this tourism piece highlights a number of other possible, and less remote, locations as well: samudramaldives.com/maldives-glowing-bioluminescence-beaches/
This map highlights the growing militarization of the Arctic Ocean and its periphery. (Map from www.wsj.com/articles/americas-military-falls-behind-russia-china-race-for-melting-arctic-2a71dfac.)
AMOC (pronounced "ay-mock")-- the Atlantic Meridional Overturning Circulation -- is a network of Atlantic Ocean currents, including the Gulf Stream, that plays a pivotal role in keeping Western Europe warm relative to its latitude and distributing heat around the planet. Multiple studies have found AMOC is weakening and is now perhaps the weakest it has been in 1,000 years. The massive melting of the Greenland ice sheet, which is dumping an estimated 250 billion metric tons of ice and cold, fresh meltwater into the northern Atlantic each year, is eyed as a possible culprit. Last week a study by Danish researchers of 150 years of weather data concluded that AMOC could collapse -- as it did 12,800 years ago -- by the end of the century, perhaps even within a few years. This article from Scientific American explains the science, the unknowns, and AMOC's significance: www.scientificamerican.com/article/is-a-mega-ocean-current-about-to-shut-down/.
To paraphrase Jurassic Park's Dr. Ian Malcolm, life finds a way. This article looks at the creatures living in the North Pacific Gyre's "Great Pacific Garbage Patch." www.wsj.com/articles/pacific-ocean-garbage-patch-is-bursting-with-life-e57b04f3
Scientists associated with China's Institute of Oceanology have deployed a long-term ocean observation platform to study cold seeps in the South China Sea. What are cold seeps, you might ask? This useful pair of videos from the U.S. National Oceanic and Atmospheric Administration (NOAA) explains what a cold seep (also known as a methane seep) is, what a hydrothermal vent is, and how they are different: oceanexplorer.noaa.gov/facts/seeps-vents.html
The Chagos Islands have been in the news this week. The Chagos Archipelago is in the Indian Ocean, northeast of Madagascar and Mauritius and south of the Maldives. In the 1960s and '70s, the British government forced more than 1,000 residents of the Chagos Islands to leave their homes to make way for a military base on the largest of the islands, Diego Garcia, that was then leased to the United States. The Chagossians have fought for their return ever since. This week Human Rights Watch called for Britain to pay reparations to the Chagossians and allow for their return to their homes.
www.thetimes.co.uk/imageserver/image/%2Fmethode%2Ftimes%2Fprod%2Fweb%2Fbin%2F21f707ea-3949-11e9-8581-34e77e2582ca.png Nearly 11 billion snow crabs have disappeared from the northern Pacific and Arctic. Yes, climate change almost certainly played a role, but is the more complex truth that we counted wrong and ate them? nautil.us/where-have-all-the-snow-crabs-gone-248247
According to the National Oceanic and Atmospheric Administration (NOAA), this year high-tide or "sunny day" flooding -- when water floods streets and bubbles up through storm drains without storm activity -- on the East Coast of the U.S. is expected to show an increase of more than 150% since 2000. NOAA's calculations are based on data from a network of water-level stations along the U.S. coasts and Great Lakes. This interactive mapping site shows past, present, and anticipated 2050 sunny day flooding levels. (In Washington, DC, for example, the average number of high-tide flooding events in 2000 was three; in 2021, it was five, and by 2050, it is forecast to be 55-85.) tidesandcurrents.noaa.gov/HighTideFlooding_AnnualOutlook.html
Oceans cover nearly three-fourths of our planet's surface, but what goes on under the water is usually out of sight and, often, out of mind. This article brings to the surface changes in the biogeography of the waters off Maine: divemagazine.com/scuba-diving-long-reads/i-dived-the-gulf-of-maine-and-saw-one-fish
When a U.S. submarine ran into an unmapped seamount in the South China Sea two months ago, many wondered how that could happen. It turns out only 19% of the world's sea floor has been mapped. Moreover, the South China Sea is known to have particularly tricky underwater terrain. You can use this mapping tool from the General Bathymetric Chart of the Oceans (GEBCO) to visualize ocean topography: download.gebco.net/ GEBCO is working to produce a complete, publicly available map of the world's oceans by 2030.
Conservationists are trying to safeguard the region of the Arctic Ocean that will be the most likely to persist as frozen ice according to climate models. This Last Ice Area, as it is being called, stretches from northwestern Greenland into the Canadian Arctic Archipelago and may serve as a refuge for organisms that depend on sea ice, from polar bears to fish and crustaceans to microbes. www.sciencenews.org/article/arctic-last-ice-area-climate-change
Stronger-than-usual trade winds are shifting water temperatures in the Pacific Ocean, creating a La Niña effect that is expected to influence weather patterns through the winter and into the spring. Because La Niña impacts vary with the location, check out the maps in this article to see what might be in store for you: www.wsj.com/articles/la-nina-is-coming-to-shape-winter-forecasts-what-to-know-11636666122
Released earlier this month, this animation illustrating comparative ocean depths is worth checking out: www.youtube.com/watch?v=Q5C7sqVe2Vg Earlier this week researchers announced the completion of the Allen Coral Atlas, the first ever interactive mapping tool of the world's shallow coral reefs. Building on the work of more than 450 research teams and nearly 2 million satellite images, the atlas is named for the late Microsoft co-founder and philanthropist Paul Allen who was an early supporter of the project. allencoralatlas.org/atlas/#6.00/20.1359/-155.5908
Did you know that there are waterfalls underwater?? The largest waterfall in the world is the Denmark Cataract, 2000 feet under the ocean in the Denmark Strait that separates Iceland and Greenland. Cold, dense water flows over the top of an undersea ridge and rapidly sinks two miles to the ocean floor, creating a "downward flow estimated at well over 123 million cubic feet per second," making this the world's largest and highest waterfall by a long shot. (For comparison, Angel Falls is 0.6 miles tall, and average flow over Victoria Falls is 33 thousand cubic feet per second.) oceanservice.noaa.gov/facts/largest-waterfall.html
The National Geographic Society has (finally) declared the waters around Antarctica to be the world's fifth ocean. The Southern Ocean, defined as the waters in the Southern Hemisphere south of 60 degrees latitude which roughly corresponds to the ocean encircled by the Antarctic Circumpolar Current, can now join the other four oceans -- Atlantic, Pacific, Indian, and Arctic -- on the geography bee :-). National Geographic is late to the party: scientists, the U.S. National Oceanic and Atmospheric Administration, and the U.S. Board on Geographic Names (which is responsible for uniform geographic name usage across the federal government) have recognized the Southern Ocean since the 1990s. www.nationalgeographic.com/environment/article/theres-a-new-ocean-now-can-you-name-all-five-southern-ocean
Like the hurricane season in the northern Atlantic Ocean, the cyclone season in the northern Indian Ocean is generally at its most intense from May to November. Over the last week, the cyclone season began with Cyclone Tauktae (Burmese for "gecko"), the biggest storm to hit the north coastal Indian state of Gujarat in more than 20 years. (Moving nearly 200,000 people in low-lying areas to shelters has also raised concerns about the spread of COVID in the coming weeks.) This satellite image shows Tauktae as it approached Gujarat: c.ndtvimg.com/2021-05/4uaunabc_cyclone-tauktae650_625x300_17_May_21.jpg
This map has been in the news this week as climate scientists are trying to call attention to the impact of cooling waters off Greenland's southeastern coast: www.cbsnews.com/news/climate-change-map-warning/
The Gulf Stream, which carries 30x more water than all the world's rivers combined, has played a pivotal role in shaping climate, biogeography, and human civilization in Europe, North America, Africa, South America, and even Asia. Now, a growing body of scientific research is finding this critical conveyor belt of thermal energy is slowing and weakening. This article from The New York Times walks readers through the science and its implications. www.nytimes.com/interactive/2021/03/02/climate/atlantic-ocean-climate-change.html
A new report finds that the planet is losing 1.2 trillion tons of ice each year, up from 760 billion tons in the 1990s, and the pace of ice loss is accelerating. Scientists used satellite data to study land and sea ice and found the areas experiencing the greatest loss of ice are Greenland and Antarctica, where warming water is eating away at glaciers and ice sheets where they meet the sea. Moreover, the report finds that previous estimates fail "to fully account for the role of ocean undercutting" and sea-level rise from melting ice "may be underestimated by 'at least a factor of 2.'” ... “'It’s like cutting the feet off the glacier rather than melting the whole body,' said Eric Rignot, a study co-author and a glacier researcher at NASA’s Jet Propulsion Laboratory and the University of California at Irvine. 'You melt the feet and the body falls down, as opposed to melting the whole body.'” www.washingtonpost.com/climate-environment/2021/01/25/ice-melt-quickens-greenland-glaciers
Some of the first detailed maps of the seafloor were produced by Marie Tharp, a geologist and cartographer who was barred from ocean-mapping voyages because she was a woman. Instead, she stayed ashore and analyzed the data collected. Her iconic maps -- like this one from 1977 www.sciencenews.org/wp-content/uploads/2021/01/010521_sn100_earth_spotlight-tharp_inline1-1004x580.jpg -- revolutionized the understanding of ocean topography and were instrumental in tipping the scales toward continental drift theory. (from www.sciencenews.org/article/marie-tharp-maps-plate-tectonics-seafloor-cartography)
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