Humans Aren’t Just Changing the Climate. We’re Changing ‘Life Itself’
The earth has warmed barely a single degree Celsius, and yet virtually no place on the planet is unaffected by climate change. That’s the conclusion of both a new study published in the journal Science and a popular-science book out this week, The Unnatural World, by David Biello, the science curator at TED and a Scientific American contributing editor.
“This new age is not just climate change,” Biello writes, “it is everything change: the sky, the sea, the land, the rocks, life itself.”
The Science article reviews dozens of field studies and assembles them into a mosaic of ubiquitous change, from the genes of organisms to entire regions. More than 80 percent of the 94 biological and ecological systems surveyed show signs of the changing climate. Led by Brett Scheffers of the University of Florida, a team of 17 scientists trawled academic journals and enumerated observed changes across terrestrial, marine, and freshwater environments. The study’s seven pages are a dense catalog of pervasive, dynamic weirdness that paint a picture of changing ecosystems.
No particular item should strike fear in the hearts of readers but, taken together, the data portray a living world that’s trying to cope. Some highlights: Pink salmon are migrating about two weeks earlier in the summer than they did 40 years ago, spawning in ever-warmer waters and causing the fish’s genome to change. Southern flying squirrels, native to the eastern U.S., are becoming northern flying squirrels, now native to the Pacific Northwest, Canada, and Alaska. Colors—which help determine an animal’s sensitivity to light and consequently its ability to thrive in unfamiliar conditions—are shifting in butterflies, dragonflies, and birds. Some places have new diseases, and old diseases have arrived in new places.
The changes, large and small, illuminate the overarching global and regional changes that scientists have warned about, and now documented, for decades. The chemical and physical stability of many ecosystems, and therefore biodiversity, are under assault. The consequences for human society are both foreseen and unforeseen. “Losing genetic resources in nature may undermine future development of novel crop varieties and compromise key strategies that humans use to adapt to climate change,” the Science authors write.
They also suggest where to start: “It is now up to national governments to make good on the promises they made in Paris” to cut emissions and keep ecosystems safe. President-elect Donald Trump has vowed to leave the historic climate accord, backed by almost 200 countries.
Change is so pervasive that geologists, keepers of the earth’s chronology, are considering the dramatic gesture of creating a new epoch, called the Anthropocene, to mark humanity’s influence.
The Anthropocene is the frame through which Biello peers in The Unnatural World. Read together, the book and the Science article demonstrate the astounding scale of human influence on the natural systems that sustain our planet.
“One of the longest-lived impacts of this new people’s epoch, longer lasting even than all the CO₂ piling up in the atmosphere,” Biello said about the Science paper, “will be our impact on evolution. The question now is: Will the Anthropocene be a blip in the rock record, like an asteroid impact, or can people learn to ameliorate our impacts and lengthen the span of this new epoch?”