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Sea Levels Rose Faster Than Expected Last Year. Blame Global Warming - But What Happens Next?

1 month 1 week ago
Though global sea levels "varied little" for the 2,000 years before the 20th century, CNN reports that sea levels then "started rising and have not stopped since — and the pace is accelerating." And sea level rise "was unexpectedly high last year, according to a recent NASA analysis of satellite data." More concerning, however, is the longer-term trend. The rate of annual sea level rise has more than doubled over the past 30 years, resulting in the global sea level increasing 4 inches since 1993. "It's like we're putting our foot on the gas pedal," said Benjamin Hamlington, a research scientist in the Sea Level and Ice Group at NASA's Jet Propulsion Laboratory. While other climate signals fluctuate, global sea level has a "persistent rise," he told CNN. It spells trouble for the future. Scientists have a good idea how much average sea level will rise by 2050 — around 6 inches globally, and as much as 10 to 12 inches in the US. Past 2050, however, things get very fuzzy. "We have such a huge range of uncertainty," said Dirk Notz, head of sea ice at the University of Hamburg. "The numbers are just getting higher and higher and higher very quickly." The world could easily see an extra 3 feet of sea level rise by 2100, he told CNN; it could also take hundreds of years to reach that level. Scientists simply don't know enough yet to project what will happen. What scientists are crystal clear about is the reason for the rise: human-caused global warming. Oceans absorb roughly 90% of the excess heat primarily produced by burning fossil fuels, and as water heats up it expands. Heat in the oceans and atmosphere is also driving melting of the Greenland and Antarctic ice sheets, which together hold enough fresh water to raise global sea levels by around 213 feet. Melting ice sheets have driven roughly two-thirds of longer-term sea level rise, although last year — the planet's hottest on record — the two factors flipped, making ocean warming the main driver. [SciTechDaily reports that between 2021 and 2023 the Antarctica ice sheet actually showed an overall increase in mass which exerted a negative contribution to sea level rise.] It's likely that an increase of about 3 feet is already locked in, Notz said, because "we have pushed the system too hard." The big question is, how quickly will it happen? Ice sheets are the biggest uncertainty, as it's not clear how fast they'll react as the world heats up — whether they'll melt steadily or reach a tipping point and rapidly collapse... [I]t's still unclear how processes may unfold over the next decades and centuries. Antarctica is "the elephant in the room," he said. Alarming changes are unfolding on this vast icy continent, which holds enough water to raise levels by 190 feet. Notz describes the ice sheet as an "awakening giant:" It takes a long time to wake up but once awake, "it's very, very difficult to put it back to sleep." The article notes that U.S. coastlines "are tracking above global average and toward the upper end of climate model projections, NASA's Hamlington said." (The state of Louisiana has one of the highest rates of land loss in the world, with some places experiencing nearly 4x the global rate of relative sea level rise.) But it's not just a problem for America. "Over the next three decades, islands such as Tuvalu, Kiribati and Fiji will experience at least 6 inches of sea level rise even if the world reduces planet-heating pollution, according to NASA.... "Entire villages in Fiji have been formally relocated," said Fijian activist George Nacewa, from climate group 350.org, "the incoming tides are flooding our roads and inundating our crops." However, if the pace accelerates rapidly, "it will be very, very difficult to adapt to, because things unfold too quickly," he said. "Humans still have control over how fast sea level rises over the next decades and centuries by cutting emissions, Notz noted." Thanks to long-time Slashdot reader RoccamOccam for sharing the news.

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EditorDavid

'I Broke Up with Google Search. It was Surprisingly Easy.'

1 month 1 week ago
Inspired by researchers who'd bribed people to use Microsoft's Bing for two weeks (and found some wanted to keep using it), a Washington Post tech columnist also tried it — and reported it "felt like quitting coffee." "The first few days, I was jittery. I kept double searching on Google and DuckDuckGo, the non-Google web search engine I was using, to check if Google gave me better results. Sometimes it did. Mostly it didn't." "More than two weeks into a test of whether I love Google search or if it's just a habit, I've stopped double checking. I don't have Google FOMO..." I didn't do a fancy analysis into whether my search results were better with Google or DuckDuckGo, whose technology is partly powered by Bing. The researchers found our assessment of search quality is based on vibes. And the vibes with DuckDuckGo are perfectly fine. Many dozens of readers told me about their own satisfaction with non-Google searches... For better or worse, DuckDuckGo is becoming a bit more Google-like. Like Google, it has ads that are sometimes misleading or irrelevant. DuckDuckGo and Bing also are mimicking Google's makeover from a place that mostly pointed you to the best links online to one that never wants you to leave Google... [DuckDuckGo] shows you answers to things like sports results and AI-assisted replies, though less often than Google does. (You can turn off AI "instant answers" in DuckDuckGo.) Answers at the top of search results pages can be handy — assuming they're not wrong or scams — but they have potential trade-offs. If you stop your search without clicking to read a website about sports news or gluten intolerance, those sites could die. And the web gets worse. DuckDuckGo says that people expect instant answers from search results, and it's trying to balance those demands with keeping the web healthy. Google says AI answers help people feel more satisfied with their search results and web surfing. DuckDuckGo has one clear advantage over Google: It collects far less of your data. DuckDuckGo doesn't save what I search... My biggest wariness from this search experiment is like the challenge of slowing climate change: Your choices matter, but maybe not that much. Our technology has been steered by a handful of giant technology companies, and it's difficult for individuals to alter that. The judge in the company's search monopoly case said Google broke the law by making it harder for you to use anything other than Google. Its search is so dominant that companies stopped trying hard to out-innovate and win you over. (AI could upend Google search. We'll see....) Despite those challenges, using Google a bit less and smaller alternatives more can make a difference. You don't have to 100 percent quit Google. "Your experiment confirms what we've said all along," Google responded to the Washington Post. "It's easy to find and use the search engine of your choice." Although the Post's reporter also adds that "I'm definitely not ditching other company internet services like Google Maps, Google Photos and Gmail." They write later that " You'll have to pry YouTube out of my cold, dead hands" and "When I moved years of emails from Gmail to Proton Mail, that switch didn't stick."

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EditorDavid