Name: 關於氣候變化，他們沒有告訴你的是什麼？ (What They Haven't Told You about Climate Change)
Uploaded: 2021-01-14T06:35:04.000Z
Duration: 4 min 55 s
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情態副詞

That's true about life. And it's true about
the climate. The climate has been constantly

基礎被動語態

changing since the earth was formed 4.6 billion
years ago.

For example, in just the past 2000 years,
we have seen the Roman Warm Period,

when it was warmer than today...Then came the cooler
Dark Ages... Followed by the Medieval Warm period,

when it was at least as warm as today...
Then we had the Little Ice Age -- that drove

the Vikings out of Greenland. And, most recently,
a gradual 300-year warming to the present day.

That's a lot of changes. And, of course,
not one of them was caused by humans.

During the past 400,000 years, there have been
four major periods of glaciation

-- meaning that vast sheets of ice covered a good part
of the globe -- interrupted by brief interglacial periods.

We are in one of those periods right
now. This is all part of the Pleistocene Ice Age

which began in earnest two and a half
million years ago. It's still going on,

which means that we are still living in an ice age.
That's the reason there's so much ice at the poles.

Thirty million years ago the earth
had no ice on it at all.

So, then, what about carbon dioxide, the great
villain of the Global Warming alarmists?

Where does that fit in to this picture? Not as neatly
as you might think.

Temperatures and carbon dioxide levels do
not show a strong correlation. In fact,

over very long time spans -- periods of hundreds
of millions of years --

they are often completely out of sync with each other.

Over and over again, within virtually any
time frame, we find the climate changing

-- for reasons we do not fully understand. But we
do know there are many more factors in play

than simply the concentration of CO2 in the
atmosphere -- factors such as the shape and

size of the earth's elliptical orbit around
the sun, activity from the sun, and the amount

of wobble or tilt in the earth's axis, among
many others. Even the relatively short 300-year

period from the peak of the Little Ice Age
to the present has not been steady.

The latest trend has been a warming one, but it began
nearly a century before there were significant

carbon dioxide emissions from burning fossil
fuels. And, there has been no significant

warming trend in the 21st century. Contrary
to media headlines,

the trend over the past couple of decades has been essentially flat.

Meanwhile human-caused CO2 emissions are higher
than ever. About 25 percent of all the CO2

emissions from human sources have occurred
during this period of no net warming.

So, what are we in for next? Will the temperature
resume an upward trend?

Will it remain flat for a lengthy period? Or, will it begin to
drop? No one knows.

All the information I've presented -- the
increases, decreases and plateaus in temperature

over the ages and into the last centuries
-- is available to anyone who wants to seek it out.

Yet to state these simple facts is
to risk being called a "climate change denier."

Not only is that absurd, it's mean-spirited.
It's absurd because no one, not even the most

fervent skeptic, denies that the climate is
changing. And it's mean-spirited because to

call someone a climate change denier is to intentionally link them to people who deny the Holocaust.

So, maybe it's time to stop
the name-calling.

Predicting the climate, one of the most complex
systems on earth with thousands of inputs,

many of which we don't understand, isn't an
exact science, or anything close to it.

Maybe it's just a tad arrogant to suggest that we
can predict the weather or the climate

or just about anything 60 years from now.

The science is not "settled." The debate is
not over. The climate is always changing.

I'm Patrick Moore, Co-Founder of Greenpeace, for 
Prager University.