Lecture #6 Flashcards Preview

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Flashcards in Lecture #6 Deck (47):
1

Climate is a function of the interactions of which 5 spheres?

Atmosphere
Hydrosphere
Lithosphere
Cryosphere
Biosphere

2

Because climate change is nothing new, why are we so concerned?

Concern today is the rate at which the temperature is changing

3

What was the last ice age?

18 000 years ago
-Canada under 3km of ice

4

What is the hockey stick graph?

The rapid increase in temperature in the past 100 years

5

What are the 4 general causes of climate change?

1. Variation in solar radiation
2. Changes in composition of the atmosphere (this is the only one we can change)
3. Changes in earths surface
4. Variations in earths orbit

6

What is a sun spot?

A cool region of high magnetism on the sun
-cool areas on the sun that are surrounded by faculae (bright areas that emit high amounts of energy)

7

When does the sun tent to emit more energy?

During periods of high sunspot activity
-cycles of every 11 years

8

what is the residence time of CO2?

100 years
-effects will not be felt for decades

9

What are ice cores used for?

Can glimpse into the past climate as ice layers are formed every year, and air bubbles are trapped within
-we have climate data up to 600,000 years in the past

10

What is dendrochronology?

study of tree rings,
bigger the ring the better the year

11

As Pangea was separating what did it create at the same time?

new ocean currents

12

What is the Malankovitch Theory?

The theory proposes that 3 separate phenomena relating to earth orbit lead to climate change

13

What are the 3 Milankovitch Cycles?

1. Eccentricity
2. Precession
3. Obliquity

14

What is Eccentricity?

Changes in the shape of earth orbit from circular to elliptical
-100,000 year cycle
-accounts for ice ages

15

What is Precession?

The wobble of earth axis?
-23,000 year cycle

16

What is Obliquity?

Changes in the tilt of earths Axis
-41,000 year cycle
-further the angle, the more ice you'll get

17

Why does the Greenhouse effect exist?

GHG's allow solar radiation to pass through but they absorb infrared radiation

18

What are the 3 main GHG's?

CO2
H2O vapour
CH4

19

What is the concern with greenhouse effect?

Humans are enhancing the greenhouse effect by adding more gases to the atmosphere

20

Does O3 occur naturally?

Yes it does in the stratosphere but there is a little bit towards the earths surface int h troposphere
-we need it to survive

21

What chemicals destroy the O3 layer?

CFCs which were found in appliances, spray cans etc.

22

How did we get rid of the CFCs?

Montreal protocol in 1987- worldwide agreement amoung countries to reduce the CFC concentrations

23

How do CFCs destroy the O3 layer?

UV radiation breaks the CFC molecule apart and causing Cl to roam free
-Cl rapidly destroys the layer
-CFC molecule has a long residence time

24

What does a decrease in O3 mean for us?

Increase UV radiation which causes skin cancer

25

Acid rain definition

Precipitation the combines with pollutants that turn the precipitation acidic

26

What are the elements that render rain acidic?

Sulfur and nitrogen oxides

27

what is the normal pH of rain?

~5.5
-naturally acidic

28

Positive feed back definition

A process in a system that encourages the continuation of the original process

29

What is an example of a positive feedback?

Melting of the polar ice

30

What are climate models?

Estimating how much eh earth will warm.
-Forecasts for the next 100 years, earth will warm by 1.5 degrees

31

What protocol was meant to slow climate change?

Kyoto 1997
-objective was to reduce GHG emission to 5% below 1990 levels by 2010
-DIDNT WORK LOL

32

What are some of the potential impacts of climate change?

-Polar areas warm the most
-Boreal forest extending North
-Agriculture shifting north
- Precipitation changing thus affected habitats

33

What happen when the polar ice melts?

Sea levels rise
-Populated coastal cities are at risk here

34

What can Island countries do to prevent sea level rising?

Sea walls (not too much)
-poor island countries can't afford to do this

35

What is the most serious impact of climate change that effects humans the most?

Sread of Malaria
-mosquitos thrive in warm and wet climates

36

What impacts will CC have one biodiversity?

-Species extinction
-Coral bleaching
-Loss of flora and fauna

37

How many deaths has climate change caused?

160,000
-mostly due to malaria and malnutrition

38

What are the 2 different philosophies on the relationship between humans and nature?

1. humans are simply one component of the natural world (more egalitarian view)
2. Humans are separated from nature (We are better than all other species)

39

What are the 2 different philosophies that dictate our actions based on our relationships with nature?

1. Living in harmony (sustainable development)
2. Exploiting nature for economic gain (ignoring the cost of resource extraction)

40

What are the 2 realities of natural resources?

1. Many natural resources are finite
2. using resources creates waste products
-but we've created a society and economy in which these 2 realities are neglected

41

What is the Precautionary Principle?

When there is a risk involved, to either humans or the environment, we should still act even if there is some uncertainty about the risk. there is a social responsibility to protect the public and the environment from harm

42

How does the Precautionary principle relate to climate change??

We want to be 100% sure the gases are causing the change but science isn't 100% correct so we should try and fix our ways anyways just incase

43

What are some renewable energies?

Solar
Wind
Hydro

44

How much power can one wind turbine generate?

6 MW
-enough to power a lot of homes

45

What are some issues with Wind energy?

Cost
Coise
habitat distribution
NIMBY

46

Best places to put wind turbines in Ontario?

Southwestern because we can't put them in the middle of the lakes

47

Problems with hydroelectric?

Loss of land
Displaced population
Chemical leaching
destruction of habitat