Chapter 1: Intro to climate change

Question 1

Global warming is

Answer 1

the gradual rise in the earth’s temperature caused by high levels of CO2 and other greenhouse gases (GHGs) in the atmosphere

Question 2

Global warming occurs when

Answer 2

the radiation balance of the planet is disrupted

Question 3

As global climate is determined by the …………………………. global warming results in ……………………

Answer 3

radiation balance of the planet

corresponding change in climate

Question 4

There are three fundamental ways the Earth’s radiation balance can change, thereby causing a climate change:

Answer 4

1. changing the incoming solar radiation (e.g., by changes in the Earth’s orbit or in the Sun itself),
2. changing the fraction of solar radiation that is reflected (this fraction is called the albedo – it can be changed, for example, by changes in cloud cover, small particles called aerosols or land cover), and
3. altering the longwave energy radiated back to space (e.g., by changes in greenhouse gas concentrations).

Question 5

local climate also depends on

Answer 5

how heat is distributed by winds and ocean currents

Question 6

A greenhouse gas (GHG) is

Answer 6

any gas in the atmosphere that absorbs and emits radiation in the thermal infrared range. These are the fundamental cause of the greenhouse effect, which results in global warming.

Question 7

explain how the green house effect warms the earth

Answer 7

• short wave energy heats the surface
• long wave energy radiate into atmosphere then into space
• GHG absorb some of the energy and trap it in the LOWER atmosphere and emit heat energy in all direction
• less heat radiate into space
• earth is warmer

Question 8

Thus, the greenhouse effect is a natural occurrence that maintains Earth’s average temperature at approximately ………., warmer …………… than it would be otherwise ………………..

Answer 8

288 K (15 c)

33 K

255 K (-18 c)

Question 9

Many greenhouse gases occur

Answer 9

• NATURALLY: Carbon dioxide, methane, water vapor, and nitrous oxide are naturally present in Earth’s atmosphere.
• HUMAN MADE: such as chlorofluorocarbons (CFCs), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6)

Question 10

Each molecule of greenhouse gas becomes energized by

Answer 10

the long wave radiation.

• The energized molecules of gas then emit heat energy in all directions.
• By emitting heat energy toward Earth, greenhouse gases increase Earth’s temperature.

Question 11

……………….. resulted in a sharp rise in GHG emissions

Answer 11

Increasing population and dependence on fossil fuels for energy

Question 12

For example, CO2 concentrations were fairly stable at …………….. before the Industrial Revolution (1950). Now, they hover around ……………….. and more

Answer 12

280 ppm

370 ppm

Question 13

Climate sensitivity is the term used to express

Answer 13

the relationship between the human-caused emissions like CO2 and other GHGs that add to the Earth’s greenhouse effect and the temperature changes that will result from these emissions.

• how much the average global surface temperature will increase if there is a doubling of greenhouse gases in the air.
• direct measure of how the earths climate will respond to doubling

Question 14

That value, according to the most recent IPCC report, is ………….. degrees Celsius, with a range of uncertainty from……………

Answer 14

3

2 to 4.5 degrees.

Question 15

This sensitivity depends primarily on

Answer 15

all the different feedback effects, both positive and negative, that either amplify or diminish the greenhouse effect.

Question 16

There are three primary feedback effects —

Answer 16

• clouds,
• sea ice and
• water vapor;

these, combined with other feedback effects, produce the greatest uncertainties in predicting the planet’s future climate.

Question 17

With no feedback effects at all, the change would be

Answer 17

1 degree celcius

Question 18

Clouds are a good example. Clouds can have ……………. feedback. depending on ………..

Answer 18

positive or negative

• their altitude and
• the size of their water droplets

Question 19

Clouds are a good example. Clouds can have either a positive or negative feedback effect, depending on their altitude and the size of their water droplets. Overall, most scientists expect this net effect to be

Answer 19

positive, but there are large uncertainties

Question 20

It is important to note that climate sensitivity is figured on the basis of an overall

Answer 20

doubling, compared to pre-industrial levels, of CO2 and other GHGs

Question 21

It is important to note that climate sensitivity is figured on the basis of an overall doubling, compared to pre-industrial levels, of CO2 and other GHGs.

• But, the actual increase might be greater in the long run because

Answer 21

greenhouse gas levels in the atmosphere could more than double without strong policies to control emissions.

Question 22

But in the short run, the actual warming could be less than suggested by the climate sensitivity, since due to

Answer 22

the thermal inertia of the ocean, it may take some time after a doubling of the concentration is reached before the climate reaches a new equilibrium

Question 23

anomalies are analysed to

Answer 23

understand the global temperature changes, rather than the actual temperature

Question 24

A temperature anomaly is the

Answer 24

between the temperature that is actually occurring and a long term average temperature (reference temperature).

• In other words, the long-term average temperature is one that would be expected; the anomaly is the difference between what you would expect and what is happening.

Question 25

A positive anomaly means that

Answer 25

the temperature was warmer than normal

Question 26

negative anomaly indicates

Answer 26

that the temperature was cooler than normal

Question 27

The main reason for using temperature anomalies rather than analysing the temperature directly, is that:

Answer 27

• The actual temperature can vary sharply over short distances, but its anomalies are constant over much longer distances.
• This makes the calculation of anomalies more accurate by requiring a less dense measurement network.

Question 28

Using anomalies, the departure from an “average,” allows

Answer 28

more accurate descriptions over larger areas than actual temperatures for easier analysis

Question 29

Arctic sea ice extent 1979-2005

Answer 29

• Sea ice extent is a measure of the surface area of the ocean covered by sea ice.
• The sea ice extent in the Arctic, measured in September of each year (when sea ice extent reaches its annual minimum), has decreased by about 36% since 1979

Question 30

explain how sea ice extent cause warming

Answer 30

• increase in air and ocean temp decrese extent (melting of sea ice)
• reduce area of white surface
• less raduation is reflected
• become dark ocean surface (absorb radiation)
  
  • snow covered absorb 20%
  • ice free area absorb 90%
• warm ocean
• melt ice from below and release heat to the atmosphere before ocean refreezes in winter
• less sea ice
• warmer climate

Question 31

effects of warming due to the decrease of sea ice extent

Answer 31

• wind patterns in NH shift (as Arctic atmosphere warms)
• risk of erosion along coastlines
• changes the presence of marine species in some areas
• effecting commercial fish stocks (and economics of local towns)

Question 32

Impacts of Global Warming

Answer 32

• Sea level rising and increased coastal flooding
• An Increase in Extreme Weather Events
• Heavier precipitation and flooding
• More severe droughts in some areas
• Melting Ice
• Impacts on Agriculture
• Plant and animal range migration

Question 33

Sea level rising and increased coastal flooding

Answer 33

• global sea level increased 8 inches since 1880
  
  • rising faster in some areas
• global warming is
  
  • accelerate the rate of rise
  • increasing flood risk to low laying land and coastal properties (development encouraged by insurance)

Question 34

An Increase in Extreme Weather Events

Answer 34

• global warming causes increase in
  
  • heat waves
  • coastal flooding
  • extreme precipitation events
  • severe drought
  • more powerful hurricanes

Question 35

Heavier precipitation and flooding

Answer 35

As temperatures increase, more rain falls during the heaviest downpours, increasing the risk of flooding events.

Question 36

More severe droughts in some areas

Answer 36

Climate change affects a variety of factors associated with drought and is likely to increase drought risk in certain regions

Question 37

Melting Ice

Answer 37

• temperatures rising in poles
  
  • especifically arctic
• glaciers are melting faster than snow and ice is forming

rate of melting is expected to accelerate and cause more sea level rise

Question 38

Impacts on Agriculture

Answer 38

• global warming
  
  • rising temperature
    
    • heat waves
    • heavy precipitation
    • severe drought

these effect crop production and the food supply

Question 39

Plant and animal range migration

Answer 39

• A changing climate affects the range of plants and animals, changing their behavior and causing disruptions up and down the food chain.
• The range of some warm-weather species will expand, while those that depend on cooler environments will face shrinking habitats and potential extinction