Climate Change

Question 1

What are the 2 pieces of evidence used to define the start of the Anthropocene?

Answer 1

1. The Colombian Exchange
2. Atomic Weapons Testing

Question 2

Describe the Colombian exchange

Answer 2

1. New 🌎 species brought to Europe, Old 🌎 species taken to the Americas (the exchange)
2. New diseases/bacteria viruses (e.g smallpox) killed around 50 million (90%) indigenous American —>huge areas of farmland abandoned
3. forests grew + absorbed huge quantities of CO2 reducing CO2 amounts around the 🌎
4. GLOBAL COOLING for 200 years (little ice 🧊age)

Question 3

Describe the hypothesis of Atomic Weapons Testing

Answer 3

1. USA ends WW2 by dropping atomic bombs on two Japanese cities —> as Cold War deepens = development of nuclear weapons
2. Radiative material from tests enters atmosphere and spreads all around the world.
3. Increase in radiation levels accumulates in sediment and bones/tissues of organisms
4. Criticism - though recorded in sediment, impact was small, radiation levels higher than 1945 but within SAFE LIMITS

Question 4

What is Anthropogenic behaviour?

Answer 4

The Anthropocene = man made climate change, human activity pushes Earth’s climate system beyond natural limits.

Question 5

What is the Greenhouse effect (simple)?

Answer 5

A natural process that occurs when greenhouse gases in the atmosphere trap heat from the Sun, warming the Earth’s surface

Question 6

Explain greenhouse effect

Answer 6

1. shortwave radiation, sun to earth —> atmosphere traps infrared radiation—> Earth heats up and emits long wave radiation —> some infrared radiation escapes in space, earth cools —>in and out radiation is BALANCED, temp. is stable

Natural gases and effects

Question 7

Percentage contribution of CO2, flurogases, methane and nitrous oxides in atmosphere and greenhouse strength (if co2 is 1)

Answer 7

CO2 = 75%, 1
Fluoro-Gases = 2%, approx. 10,000
Methane = 17%, 30
Nitrous Oxide = 6%, 600

Question 8

Where did the CO2, Fluor-Gases, Methane and Nitrus Oxide come from?

Answer 8

CO2= burning fossil fuels to generate electricity⚡️ and to power transport 🚗, deforestation 🌲
Fluoro-Gases= manmade gases 🦠in aerosol cans and refrigerators
Methane = agriculture (cattle 🐄 and rice), melting permafrost 🥶
Nitrus Oxide = Agriculture (fertiliser manufacturer and use 💩), burning fossil fuels 🔥

Question 9

Top 5 Countries responsible for global emissions and 3 common factors

Answer 9

1. China
2. USA
3. India
4. Russia
5. Japan

• High populations,
• developed (or rapidly developing) economies, - abundant fossil fuel resources (coal, oil, gas)

Question 10

Explain enhanced greenhouse effect and what increases the concentration of GG in armosphere.

Answer 10

1. earth surface heats up + emits long wave radiation, trapped in atmos. by GG —> planet heats up bc more energy ENTERS atmos. —> human activity increases GG in atmos. —> in and out radiation is UNBALANCED

more industrial action, human activity thickens blanket = less outgoing radiation escapes into space

Question 11

How have atmospheric carbon dioxide levels changed over time (pre-industrial to present)?

Answer 11

pre-industrial (1800) = 280 ppm (part per mil.)
1958 = 310ppm
2020 = 410 ppm

(increased by 130ppm since 1800)
ROUGHLY 50%

Question 12

Equation to work out % increase

Answer 12

% increase = final - initial/ initial (x 100)

Question 13

Describe 5 pieces of evidence that demonstrate the Earth’s climate and natural systems are changing

(key word describe)

Answer 13

1. Drought and Extreme Heat 🥵
2. Positive Feedback loops 🔁
3. Storms ⛈️
4. Ice and Oceans 🧊 🌊
5. Wildlife Ecosytems 🐼

Question 14

What is a positive feedback loop and give some examples (melting permafrost in Arctic Tundra)?

Answer 14

1. when something happens and in doing so causes itself to happen again more intensely (aka vicious cycle/snowball effect)
2. ❄️melting permafrost in Artic Tundra —> releases methane –> more warming, more permafrost melting. White surfaces replaced with darker ones, the Earth’s albedo (% of sunlight reflected into space) decreases

Question 15

Give another example of a positive feedback loop (wildfires in California)

Answer 15

1. increased temperatures = more evaporation
2. drier wood, easier to catch fire
3. Autumn rainstorms, due to hotter climate, arriving later (extended summer)
4. warmer at higher altitude = more pine beetles = weakened forest
5. more dry wood and drought = less carbon sequestration

(CO2 emissions into atmosphere, melting glaciers -> rising sea levels and drier wood)

Question 16

What is the “albedo effect” and give an example (glacier retreat due to wildfires)

Answer 16

1. Albedo effect = the ability of a surface to reflect sunlight
2. soot and ash from wildfires settles on the ice, darkening the surface and decreasing reflectivity (more ice melts)

Question 17

What is “carbon sequestration”?

Answer 17

the process of capturing and storing atmospheric carbon dioxide

Question 18

What is a ‘carbon footprint’ (CO2e) ?

Answer 18

The total climate change impact of all the greenhouse gases caused by an item, organisation, person or activity.

expressed in terms of amount of CO2 that would have the equivalent impact over 100yrs

Question 19

How can you reduce your carbon footprint?

Answer 19

1. Use public transportation
2. eat local food and a plant-based diet (cheese, beef, lamb =ruminants that give off methane and less carbon intensive method of transportation)
3. use energy-efficient appliances
4. reuse and recycle old items

Question 20

Who is most responsible for taking action against climate change?

Answer 20

Developed countries and rich countries in the WEST (largest emitters of CO2 ) must lead by example and move forward in a more SUSTAINABLE way.

Question 21

How can governments make policies to mitigate against climate change?

Answer 21

1. Invest in renewable energy, using alternative energy such as solar, wind or tidal can reduce the use of fossil fuels and use low carbon intensive tech.
2. Invest in carbon capture and green hydrogen removal of CO2 from waste gases from power stations and then storing it in old oil and gas fields or coal mines underground
3. promote plant based diets (less meat and dairy = less methane from ruminants)
4. Invest in electric vehicles and reduce passenger air travel/aviation

OVERALL = renewable resources

Question 22

What does “net zero” emissions mean?

Answer 22

net zero= the balance between the amount of GG produced and the amount removed from the atmosphere