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Flashcards in Chapter 21 Deck (40)
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1

Climate system

multidemensional system of many interacting parts
includes: atmosphere, hydrosphere, geosphere, biosphere, cryosphere

2

Climate impacts geologic processes

weathering, flooding, mass wasting

3

Geologic process affect climate

volcanism and mountain building

4

paleoclimatology

reconstructing past climate change
Instructional records only go back a couple of centuries

5

Scientists use proxy data

indirect evidence of climate change

6

Seafloor Sediments

Storehouse of Climate Data: Abundance and types of organic remains are indicative of past sea-surface temperatures

7

Oxygen Isotope Analysis

precise measure of the ratio of O18/O16
Higher ratios indicate climate was colder
-ratios trapped in calcium carbonate shells of marine organisms
-ratios vary with amount of sea ice and water temp

8

ice can be analyzed for

-oxygen isotope analysis
-Carbon dioxide ad methane (air bubbles trapped in the ice)
-Dust, volcanic ash, pollen

9

Tree Rings

Archives of environmental history
-growth rings are added each year (thickness and density of rings reflect environemental conditions

10

Other types of Proxy Data

-Fossil Pollen: Pollen can provide high-resolution records of vegetation
Best type of paleovegetation indication
-Corals- Through oxygen isotope analysis, corals are used as paleothermometers and precipitation proxies
-Historical Data

11

Composition of the Atmosphere

-Air is a mixture of many discrete gases
-Clean dry air: mostly nitrogen and oxygen, carbon dioxide is a minute component of air but can absorb and affect global climate

12

Water Vapor in atmophere

-amount varies from none to 4% of air
-source of clouds and precipitation
-can absorb heat and affect global climate

13

Ozone (Atmosphere)

-A combination of three oxygen atoms in one molecule in one molecule
-Thin layer of gas concentrated in the stratosphere
-Absorbs harmful ultraviolet radiation

14

Aerosols in atmosphere

-tiny solid and liquid particles found in the air
-Can attract moisture for cloud formation
-can block sunlight from reaching earth

15

Pressure changes with ____

height

16

Pressure in the atmosphere structure

is the weight of the air above
-Pressure at higher altitudes is less
-Average sea level pressure is 1 kilogram per centimeter

17

Earth's atmosphere is divided into four layers based on temperature

Troposphere
Stratosphere
Mesosphere
Thermosphere

18

Troposphere

-Bottom layer of atmosphere
-We live in it
-Temp decreases with increase in altitude
-Where weather occurs
-Bounded on top by tropopause

19

Stratosphere

-Temp remains constant until 20 Km then it increases
-Ozone is concentrated here
-Bounded on top by stratopause

20

Mesophere

-Temp decreases with height to mesopause
-Coldest temperatures in atmosphere

21

Thermosphere

-tiny fraction of atmosphere
- Temp increases due to absorption of solar radiation
-no defined upper limit

22

The sun emits _______ ______ in the form of rays and waves

electromagnetic radiation

-as an object absorbs radiation, molecule movement increases causing temp to rise
-key difference among electromagnetic radiation is the wavelengths

23

Basic laws governing radtiation

-All objects emit radiant energy
-Hotter objects radiate more total energy than do colder objects
-The hotter the radiating body, the shorter the wavelengths of maximum radiation
-Objects that are good absorbers of radiation are good emitters as well

24

50% solar energy passes through

atmosphere and is absorbed on Earth's surface

25

20% solar energy

is absorbed by clouds and atmospheric gases

26

30% solar energy is

reflected back to space by clouds, atmosphere, snow and ice

27

Greenhouse Affect

-Shortwave solar radiation passes through the atmosphere and heats Earth
-Longwave radiation emitted by Earth is absorbed by gases in the atmosphere (CO2 and water vapor)

28

Selective absorption and reheating of Earth is called ______ _____ and results in warming of the atmosphere

greenhouse effect

29

Plate Movements

-landmasses move closer or further from equator
-can affect ocean circulation

30

Volcanic Activity and Climate Change

effects volcanic aerosols on climate
Sulfuric acid droplets
lowered global temps
increase in atmospheric CO2