Polar bear

CLIMATE CHANGE AND LIFE ON EARTH

Climate change presents the gravest threat to life on Earth in all of human history. The planet is warming to a degree beyond what many species can handle, altering or eliminating habitat, reducing food sources, causing drought and other species-harming severe weather events, and even directly killing species that simply can’t stand the heat. In fact, scientists predict that if we keep going along our current greenhouse gas emissions trajectory, climate change will cause more than a third of the Earth’s animal and plant species to face extinction by 2050 — and up to 70 percent by the end of the century. Such a catastrophic loss would irreversibly diminish biodiversity, severely disrupt ecosystems, and cause immense hardship for human societies worldwide.

Since the Center was established, our mission has been to help protect species facing extinction, and as the threat of climate change has spread, our focus on the issue has intensified. The list of species we’ve petitioned and litigated to protect specifically from warming’s effects is constantly growing, and since today truly all species are threatened by climate change in one way or another, we’ve made fighting climate change central to our mission.

LIFE IN THE ARCTIC (AND ANTARCTIC)

The first creatures to be dramatically and visibly affected by climate change have been those in the Arctic, where the impacts of rising temperatures have been felt earlier and more intensely than anywhere else. As warmer air melts the vast expanses of sea ice that help define the Far North, all the animals depending on that ice for hunting, resting, reproducing, and other key life activities lose the platform on which their existence depends.

Iconic polar bears, fast losing the sea-ice habitat beneath their feet, have become a broadly recognized symbol of the harm climate change is causing in the fragile Arctic — mainly because of the Center’s multi-year, ongoing campaign to earn meaningful federal protection for the species. We’re also fighting to keep numerous other Arctic species — including Pacific walruses; bearded, ringed, spotted, and ribbon seals; Cook Inlet beluga whales; and yellow-billed loons— from being snuffed out by climate change.

At the other end of the Earth, around the South Pole, emperor penguins are also facing enormous threats from climate change, which causes profound changes in the Antarctic ecosystem and hurts penguins in diverse ways, from reducing prey species to causing ice shelves to collapse. Thanks to a petition and lawsuit by the Center, emperor penguins and other penguin species hailing from around the southern hemisphere are now protected under the Endangered Species Act.

LIFE BETWEEN THE POLES

The polar regions are by no means the only parts of the planet already affected by climate change. As temperatures rise worldwide, many species are forced to flee warming temperatures by moving up in elevation — like American pikas — or by moving northward or southward, away from warmer equatorial areas. Snow-dependent species like American wolverines are finding less and less of the snow they need, while forest-dwelling species like West Virginia northern flying squirrels are threatened right along with their arboreal habitat. Amphibians and fish are threatened by the drought that accompanies climate change, while reptiles like loggerhead sea turtles have been found altering their centuries-old nesting habits because of warmer ocean temperatures. Even insects are affected: Beautiful Bay checkerspot butterflies, for example, are at risk as climate change reduces food availability for their larvae. The Center works for all these species and many others.

LIFE BENEATH THE SEA

As greenhouse gases pile up in our air, the world's oceans are far from immune to the problem. First of all, with climate change comes ocean acidification, an increasingly serious threat to marine species. Much of the human-generated CO 2 spewed into the atmosphere eventually ends up in the oceans, changing seawater chemistry to make it more acidic and depleting seawater of the compounds that organisms like corals, crabs, seastars, sea urchins, and zooplankton need to build the protective shells and skeletons crucial for their survival. Because plankton are at the base of the delicate ocean food chain, ocean acidification could disrupt the entire marine ecosystem.

Climate change harms marine species in lots of other ways. Warmer water temperatures have been shown to slow the growth of phytoplankton — the microscopic plant counterpart to zooplankton — imperiling not only the species that eat these tiny plants, but all species in the ocean food chain. Climate change also causes coral bleaching, in which the stress caused by too-warm seawater induces corals to expel the symbiotic algae that give them their spectacular color. Meanwhile, sea levels rise as warmer temperatures melt Arctic ice, threatening species like Hawaiian monk seals, whose pupping beaches are increasingly engulfed by rising waters. The Center is working hard to help monk seals by litigating for more critical habitat.

Ever since the threats became clear, we've been calling attention to climate change’s effects on oceans and pressing for federal protection of species at risk. Those include the first species to ever get Endangered Species Act protection because of climate change and ocean acidification, elkhorn and staghorn corals, as well as a long list of species of all taxa, from Atlantic salmon to sea otters to Xantus’s murrelets.

Polar bear photo via Pixabay.