Biodiversity Hotspots Getting Hotter (and That's Not Good)

Biodiversity hotspots are golden places on earth where the number and diversity of animals and plants is exceptional. Environmentalists say that hotspots are the most critical of all places to protect against the ill effects of human development and climate change.

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Biodiversity hotspots are golden places on earth where the number and diversity of animals and plants is exceptional. Environmentalists say that hotspots are the most critical of all places to protect against the ill effects of human development and climate change. The term does not mean that hotter temperatures are helpful, however. And it turns out that the biggest rises in temperature will occur where hotspots are most concentrated.

Last year a team of scientists led by Camilo Mora at the University of Hawaii published a map showing in incredible detail the year in which mean annual air temperature will rise completely out of the normal range established from 1860 to 2005. Even a cool year, then, will be hotter than a hot year from the past. That extreme will be reached by 2047 in many regions if nations continue to emit carbon dioxide at current rates. But the “new abnormal” will arise even sooner in the tropics. Unfortunately, that’s where many hotspots exist. And that’s where animals are least able to adapt to a change in temperature, because they have existed for so long in a climate that has been extremely stable.

The group created eight maps that show the global hotpots for mammals, birds, reptiles, amphibians and fishes, on land and at sea—and laid those maps on top of the map that shows future temperature change. The darker reds in the map below show the regions where temperatures will reach abnormal levels earliest, and the red outlines show the hotspots for terrestrial mammals. The overlap is alarming.


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The seven maps that follow show the same temperature zones, overlaid on the hotspots for other taxa: marine mammals, terrestrial birds, marine birds, terrestrial reptiles, marine reptiles, marine fish and amphibians. Seeing where the different hotspots are located is interesting enough. Realizing the heavy overlap with excessive temperature rise is a wake-up call.

Mark Fischetti was a senior editor at Scientific American for nearly 20 years and covered sustainability issues, including climate, environment, energy, and more. He assigned and edited feature articles and news by journalists and scientists and also wrote in those formats. He was founding managing editor of two spin-off magazines: Scientific American Mind and Scientific American Earth 3.0. His 2001 article “Drowning New Orleans” predicted the widespread disaster that a storm like Hurricane Katrina would impose on the city. Fischetti has written as a freelancer for the New York Times, Sports Illustrated, Smithsonian and many other outlets. He co-authored the book Weaving the Web with Tim Berners-Lee, inventor of the World Wide Web, which tells the real story of how the Web was created. He also co-authored The New Killer Diseases with microbiologist Elinor Levy. Fischetti has a physics degree and has twice served as Attaway Fellow in Civic Culture at Centenary College of Louisiana, which awarded him an honorary doctorate. In 2021 he received the American Geophysical Union’s Robert C. Cowen Award for Sustained Achievement in Science Journalism. He has appeared on NBC’s Meet the Press, CNN, the History Channel, NPR News and many radio stations.

More by Mark Fischetti

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