In a massive new report, federal scientists contradict President Trump and assert that climate change is an intensifying danger to the United States. Too bad it came out on a holiday.
On
Friday, the busiest shopping day of the year, the federal government published
a massive and dire new report on climate change. The report warns, repeatedly
and directly, that climate change could soon imperil the American way of life,
transforming every region of the country, imposing frustrating costs on the
economy, and harming the health of virtually every citizen.
Most
significantly, the National Climate Assessment—which is endorsed
by nasa, noaa, the Department of Defense, and 10
other federal scientific agencies—contradicts nearly every position taken on
the issue by President Donald Trump. Where the president has insisted that
fighting global warming will harm the economy, the report responds: Climate
change, if left unchecked, could eventually cost the economy hundreds of
billions of dollars per year, and kill thousands of Americans to boot. Where
the president has said that the climate will “probably” “change back,” the report
replies: Many consequences of climate change will last for millennia, and some
(such as the extinction of plant and animal species) will be permanent.
The
report is a huge achievement for American science. It represents cumulative
decades of work from more than 300 authors. Since 2015, scientists from across
the U.S. government, state universities, and businesses have read thousands of
studies, summarizing and collating them into this document. By law, a National
Climate Assessment like this must be published every four years.
It may
seem like a funny report to dump on the public on Black Friday, when most
Americans care more about recovering from Thanksgiving dinner than they do about
adapting to the grave conclusions of climate science. Indeed, who ordered the
report to come out today?
It’s a
good question with no obvious answer.
The
report is blunt: Climate change is happening now, and humans are causing it.
“Earth’s climate is now changing faster than at any point in the history of modern
civilization, primarily as a result of human activities,” declares its first
sentence. “The assumption that current and future climate conditions will
resemble the recent past is no longer valid.”
At this
point, such an idea might be common wisdom—but this does not make it any less
shocking, or less correct. For centuries, humans have lived near the ocean,
assuming that the sea will not often move from its fixed location. They
have planted wheat at its time, and corn at its time, assuming that the harvest
will not often falter. They have delighted in December snow, and
looked forward to springtime blossoms, assuming that the seasons will not shift
from their course.
Now,
the sea is lifting above its shore, the harvest is faltering, and the seasons
arrive and depart in disorder.
The
report tells this story, laying simple fact on simple fact so as to build a
terrible edifice. Since 1901, the United States has warmed 1.8 degrees
Fahrenheit. Heat waves now arrive earlier in the year and abate later than they
did in the 1960s. Mountain snowpack in the West has shrunk dramatically in the
past half century. Sixteen of the warmest 17 years on record have occurred
since 2000.
This
trend “can only be explained by the effects that human activities, especially
emissions of greenhouse gases, have had on the climate,” the report says. It
warns that if humans wish to avoid 3.6 degrees of warming, they must
dramatically cut this kind of pollution by 2040. On the other hand, if
greenhouse-gas emissions continue to rise, then the Earth could warm by as much
as 9 degrees by 2100.
“It
shows us that climate change is not a distant issue. It’s not about plants, or
animals, or a future generation. It’s about us, living now,” says Katharine
Hayhoe, an author of the report and an atmospheric scientist at
Texas Tech University.
The
report visits each region of the country, describing the local upheavals
wrought by a global transformation. Across the Southeast, massive wildfires—like
those seen now in California—could soon become a regular occurrence, smothering
Atlanta and other cities in toxic smog, it warns. In New England and the
mid-Atlantic, it says, oceanfront barrier islands could erode and narrow. And
in the Midwest, it forecasts plunging yields of corn, soybeans, wheat, and
rice.
Its
projections of sea-level rise are just as ominous. If carbon pollution
continues to rise, a huge swath of the Atlantic coast—from North Carolina to
Maine—will see sea-level rise of five feet by 2100. New Orleans, Houston, and
the Gulf Coast could also face five feet of rising seas. Even Los Angeles and
San Francisco could see the Pacific Ocean rise by three feet.
Even if
humanity were to reduce the burning of fossil fuels, the report forecasts
that New Orleans could still see five feet of
sea-level rise by 2100.
Please
continue this article here: https://www.theatlantic.com/science/archive/2018/11/national-climate-assessment-black-friday/576589/
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