Social Science Section 1

Earth System Science (def + 4 subsystems)

Earth System Science (def + 4 subsystems)

way of studying natural world by isolating earth as 1 system

• geosphere/ lithosphere (land)

• hydrosphere (water, ice, clouds) ; cryosphere (ice)

• atmosphere

• biosphere

Anthropocene (def + origin)

the current geological period where humans cause climate change

• theorized since 1950

Forcings

factors that influence climate change

Order of atmospheric zones low to high “Tiny Squirrels Munch Tasty Eggs’

troposphere

stratosphere

mesosphere

thermosphere

exosphere

Explain how greenhouse gasses relate to sunlight

• green house gases are transparent to sunlight rays

• once sun rays hit earth, heat trapped in lower layers

• rays reradiated as infrared light,

• IR light absorbed by green houses gasses, trapping heat

Milankovitch Cycles (def + 3 intervals)

patterns of Earth’s movements in relation to the sun and how it influences the star’s impact on climate

intervals: different parts of earth receive more / less sunlight

• 100,000

• 41,000

• 26,000

How do volcanoes contribute to cooler temperatures

during eruption, emit layer of dust —> offer shade to large areas / globe

feedbacks

Reactions to climate change caused by forcings

Positive feedbacks

Original forcing and feedback push climate in the same direction

ex) melting polar ice sheets caused by warming. Losing ice further warms the climate

Tipping Point

caused by positive feedbacks when they push the climate to a point of NO RETURN

Negative Feedback

feedback pushes climate in the opposite direction of the original forcing

ex) Weaker Polar vertex

ex) Great Lakes

• Warm conditions: lead to more cloud formation

• Clouds cover sunlight/cause snowstorms = cooler

Archives of Society

Human-produced documents used to learn about climate history

Archives of Nature

Nature is used as a storehouse of information to learn about climate history

Proxy

Something in nature that gives insight into past climate conditions

3 most important proxies in the archives of nature

• ice cores

• trees

• soil

Purpose of ice cores for climate history

reveal previous atmospheric conditions

Purpose of trees for climate history

rings reveal previous weather conditions during specific years

dendrochronology

practice of gathering weather data from trees

Purpose of soil/sediment for climate history

reveal the composition of layers of a body of water

• coral sampling: reveal previous temperatures

In the context of society’s archives, how far do the creation of instruments used to measure climate date back?

~1700 (thermometer invention)

What advantage do the archives of society have over the archives of nature

DATING

ex) trees can describe the rainy conditions for one year, however, human records can give details down to the day and hour

In what year did Pheonix, AZ reach record-breaking temperatures for summer heat? How far do Pheonix records date?

2023

1896

Disadvantage of instrument use for studying climate history

instrumental records for climate trends only go for a century

2 examples of narrative records used as proxies to study climate history are …

1) Weather diaries

2) Ship logbooks

2 non-narrative record proxies used for climate history are…

1) highwater marks during floods

2) Grain prices

Climatology

study of climate using archives of nature

Historical Climatology/ Paleoclimatology

study of climates before 1800

Climate History

study of previous climates using archives of society

Who created the field of Climate History

Christian Pfister

Who created the field of History of Climate and Society (HCS)

Dagomar Degroot

What does scale mean in the field of HCS?

scope of investigation

What current era do we live in? how long ago did it start?

Holocene; started 11.7 thousand years ago

Era before the Holocene is…

Pleistocene, 2.58 Million years ago

Which organization proposed that ANTHROPOCENE should be the official name of the current era?

Anthropocene Working Group

• said 1950, Holocene end, Anthropocene started

In March 2024, what group rejected the proposal of Anthropocene being an official era

International Union of Geological Sciences

• rejected idea, but still wanted to keep term around

Which 2 FRENCH historians included climate in their recounts of global history before 2000

E. Le Roy Ladurie & Fernand Braudel

Climate Determinism

the argument that climate sets up the course of human history

Who wrote Silent Spring, and what was its purpose?

Rachel Carson

• show that pesticides negatively impact environment

• highlight the harmful potential humans have on earth

Dipesh Chakrabarty

believes humans are changing climate faster than natural processes can

the end :D