Flashcards in Lecture #6 Deck (47):
Climate is a function of the interactions of which 5 spheres?
Because climate change is nothing new, why are we so concerned?
Concern today is the rate at which the temperature is changing
What was the last ice age?
18 000 years ago
-Canada under 3km of ice
What is the hockey stick graph?
The rapid increase in temperature in the past 100 years
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
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)
When does the sun tent to emit more energy?
During periods of high sunspot activity
-cycles of every 11 years
what is the residence time of CO2?
-effects will not be felt for decades
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
What is dendrochronology?
study of tree rings,
bigger the ring the better the year
As Pangea was separating what did it create at the same time?
new ocean currents
What is the Malankovitch Theory?
The theory proposes that 3 separate phenomena relating to earth orbit lead to climate change
What are the 3 Milankovitch Cycles?
What is Eccentricity?
Changes in the shape of earth orbit from circular to elliptical
-100,000 year cycle
-accounts for ice ages
What is Precession?
The wobble of earth axis?
-23,000 year cycle
What is Obliquity?
Changes in the tilt of earths Axis
-41,000 year cycle
-further the angle, the more ice you'll get
Why does the Greenhouse effect exist?
GHG's allow solar radiation to pass through but they absorb infrared radiation
What are the 3 main GHG's?
What is the concern with greenhouse effect?
Humans are enhancing the greenhouse effect by adding more gases to the atmosphere
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
What chemicals destroy the O3 layer?
CFCs which were found in appliances, spray cans etc.
How did we get rid of the CFCs?
Montreal protocol in 1987- worldwide agreement amoung countries to reduce the CFC concentrations
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
What does a decrease in O3 mean for us?
Increase UV radiation which causes skin cancer
Acid rain definition
Precipitation the combines with pollutants that turn the precipitation acidic
What are the elements that render rain acidic?
Sulfur and nitrogen oxides
what is the normal pH of rain?
Positive feed back definition
A process in a system that encourages the continuation of the original process
What is an example of a positive feedback?
Melting of the polar ice
What are climate models?
Estimating how much eh earth will warm.
-Forecasts for the next 100 years, earth will warm by 1.5 degrees
What protocol was meant to slow climate change?
-objective was to reduce GHG emission to 5% below 1990 levels by 2010
-DIDNT WORK LOL
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
What happen when the polar ice melts?
Sea levels rise
-Populated coastal cities are at risk here
What can Island countries do to prevent sea level rising?
Sea walls (not too much)
-poor island countries can't afford to do this
What is the most serious impact of climate change that effects humans the most?
Sread of Malaria
-mosquitos thrive in warm and wet climates
What impacts will CC have one biodiversity?
-Loss of flora and fauna
How many deaths has climate change caused?
-mostly due to malaria and malnutrition
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)
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)
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
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
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
What are some renewable energies?
How much power can one wind turbine generate?
-enough to power a lot of homes
What are some issues with Wind energy?
Best places to put wind turbines in Ontario?
Southwestern because we can't put them in the middle of the lakes