You have a preview view of this article while we are checking your access. When we have confirmed access, the full article content will load.
Credit...Photo Illustration by Andrea D'Aquino

The Science of Climate Change Explained: Facts, Evidence and Proof

Definitive answers to the big questions.

Ms. Rosen is a journalist with a Ph.D. in geology. Her research involved studying ice cores from Greenland and Antarctica to understand past climate changes.

The science of climate change is more solid and widely agreed upon than you might think. But the scope of the topic, as well as rampant disinformation, can make it hard to separate fact from fiction. Here, we’ve done our best to present you with not only the most accurate scientific information, but also an explanation of how we know it.

Image

Climate change is often cast as a prediction made by complicated computer models. But the scientific basis for climate change is much broader, and models are actually only one part of it (and, for what it’s worth, they’re surprisingly accurate).

For more than a century, scientists have understood the basic physics behind why greenhouse gases like carbon dioxide cause warming. These gases make up just a small fraction of the atmosphere but exert outsized control on Earth’s climate by trapping some of the planet’s heat before it escapes into space. This greenhouse effect is important: It’s why a planet so far from the sun has liquid water and life!

However, during the Industrial Revolution, people started burning coal and other fossil fuels to power factories, smelters and steam engines, which added more greenhouse gases to the atmosphere. Ever since, human activities have been heating the planet.

Where it was cooler or warmer in 2020 compared with the middle of the 20th century

–1˚C

+1˚

+2˚

+3˚

No data

Where it was cooler or warmer in 2020 compared with the middle of the 20th century

–1˚C

+1˚

+2˚

+3˚

No data

Where it was cooler or warmer in 2020 compared with the middle of the 20th century

–1˚C

+1˚

+2˚

+3˚

No data

Where it was cooler or warmer in 2020 compared with the middle of the 20th century

–1˚C

+1˚

+2˚

+3˚

No data

Source: NASA Goddard Institute for Space Studies

By Veronica Penney

+1.2°C

Global average temperature compared with the middle of the 20th century

+0.75°C

+0.50°

+0.25°

–0.25°

1880

1900

1920

1940

1960

1980

2000

2020

+1.2°C

Global average temperature compared with the middle of the 20th century

+0.75°C

+0.50°

+0.25°

–0.25°

1880

1920

1960

2000

+1.2°C

Global average temperature compared with the middle of the 20th century

+0.75°C

+0.50°

+0.25°

–0.25°

1880

1920

1960

2000

By The New York Times

Source: NASA Goddard Institute for Space Studies

By Veronica Penney

30 billion metric tons

Carbon dioxide emitted worldwide 1850-2017

25

India

Rest of world

20

China

15

Russia

Other developed

10

European Union

5

Developed economies

Other countries

United States

1850

1900

1950

2000

30 billion metric tons

Carbon dioxide emitted worldwide 1850-2017

25

India

Rest of world

20

China

15

Russia

Other developed

10

European Union

Developed economies

5

Other countries

United States

1850

1900

1950

2000

30 billion metric tons

Carbon dioxide emitted worldwide 1850-2017

India

20

Rest of world

China

Russia

10

Other developed

E.U. and U.K.

Developed economies

Other countries

United States

2017

1850

30 billion metric tons

Carbon dioxide emitted worldwide 1850-2017

Rest of world

20

China

Russia

10

E.U. and U.K.

Developed economies

Other countries

United States

2017

1850

The New York Times

Note: Total carbon dioxide emissions are from fossil fuels and cement production and do not include land use and forestry-related emissions. Russia data includes the Soviet Union through 1991, but only the Russian Federation afterward.

Source: Research Institute for Environment, Energy and Economics at Appalachian State University

By Veronica Penney


Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.


Thank you for your patience while we verify access.

Already a subscriber? Log in.

Want all of The Times? Subscribe.

Advertisement

SKIP ADVERTISEMENT