Name: 気候科学。科学のクラッシュコースの歴史 #45 (Climate Science: Crash Course History of Science #45)
Uploaded: 2021-01-14T10:29:18.000Z
Duration: 11 min 34 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

基礎受動態

This image is called the Blue Marble, and it was taken in 1972 during the Apollo 17

様態の副詞

It has become a symbol not only of cool space travel, but the environmental movement back

Think about it: when you're on the earth, it seems pretty dang big and solid.

But seen from far above, it's just a blue marble flecked with beautiful green.

Inspiring, isolated, and not really all that big.

And thanks to technologies like air travel and the Internet, and to a booming human population,

And thanks to technologies… and a booming human population… it keeps losing those

Today is the history of climate science, which leads to some dark questions about the future

Scientists tend to be conservative—not politically

conservative, but careful, resistant to big claims.

So evidence for the possible end of the living world took a while to be seen as such.

One problem was the structure of modern science.

Remember how those ancient Greek, Indian, and Chinese natural philosophers tended to

study astronomy, math, the living world, and human society, all at once?

By the 1900s, professional scientists had gone in the other direction, specialization.

Scientists tended to focus on learning about one specific thing, often practically oriented

Another problem was actually epistemic: studying weather patterns in one region is useful,

How many local patterns add up to a global one?

And there are so many elements involved in the earth's systems—solar radiation, human

activity, carbon, nitrogen, water, nonhumans: how do you know which variables matter in

Big Data suddenly becomes not a source of potential answers, but a serious problem.

English inventor Guy Callendar correctly predicted rising atmospheric carbon dioxide concentration

He analyzed measurements of temperatures from the nineteenth century on, correlating them

He saw that temperature had increased and proposed that this was an effect of increasing

Most scientists were skeptical, but Callendar died convinced he was onto something.

And his work influenced a small number of scientists.

In 1957, Revelle published a paper with Hans Suess suggesting that human emissions of greenhouse

gases like CO2 might create a “greenhouse effect”—these

heat-trapping gases would be trapped in the atmosphere, not absorbed quickly enough by

the oceans—which would cause global warming.

Revelle also convinced geochemist Charles Keeling to keep measuring atmospheric CO2

concentrations at Mauna Loa Observatory, starting in 1958.

These measurements showed seasonal variation as well as a clear arc over time: the planet

In 1988, the World Meteorological Organisation established the Intergovernmental Panel on

Climate Change, or IPCC, which has become the premiere body for establishing just what

And in 1996, the governments of the world came together to ban chlorofluorocarbons or

CFCs, a group of odorless chemicals that were used in hair sprays, refrigerators, and lots

of other places… and that were causing a hole in the earth's protective ozone layer.

By the 2000s, many scientists had overcome their conservatism to speak out about global

shifts in climate which were affecting living systems of all sorts, agriculture, cities,

In 2000, atmospheric chemist Paul Crutzen coined a term for these global shifts, and—however

imperfect—it has stuck: the Anthropocene, or the “Age of Man.”

Some scholars have called into question naming this era after “the” human, as if all

Other contenders include Donna Haraway's the Chthulhucene, or Age of Science Fictional

Badness; the Manthropocene, or Age of Dudes, which not so subtly hints at the gender bias

in science; and, catching on with some historians, the Capitalocene, or Age of Political–Economics.

This is a fight among historians over how to discuss longue durée history, or history

It's also a fight among geologists about where to place so-called “golden spikes”—moments

that represent shifts in the very makeup of the earth, usually visible shifts in the fossil

In fact, the Anthropocene is a political fight about the intersection of geological epochs

The problem with the Anthropocene is there are so many good candidates for the golden

Show us, ThoughtBubble: First, there's the original fossil fuel—coal—which

was mined extensively in certain regions starting in the late 1700s and ramping up seriously

in the late 1800s—the Industrial Revolution.

Second, there's radioactive material in the form of strontium-90, which could be traced

all over the world soon after the Trinity atomic bomb test—the

So this date for the beginning of the Anthropocene would be the specific date of July 16, 1945—the

day of the Trinity Test and the birth of the Cold War.

Third, there's plastic, steel, and concrete—but especially plastic.

Humans built stuff and even had plastic before World War Two, but development took off at

This “Great Acceleration” saw rapid, often exponential growth in human population, use

of freshwater, ability to produce and move food, greenhouse gas emissions, temperature

of the earth's surface, and consumption of natural resources of all kinds.

The period of the Great Acceleration also gave rise to the first megacities, or urban

In reaction to massive urbanization, humans have also set aside more land as national

parks or greenways, creating a landscape dominated by industrial agriculture and cities but also

sporting well-defined breaks of deep green.

All of these changes can be seen in the earth's geological record, and they all symbolize

how some humans have changed the physical world.

But perhaps the best candidate is number four: chicken bones!

With more than twenty-three billion alive at any time, chickens—whose bodies have

been heavily designed by humans—are the most common terrestrial vertebrate species

Aliens visiting the ruins of earth could reasonably conclude from our fossil record that the only

life-form that ever mattered on this planet was the chicken.