Climate Change Flashcards
What are the 2 pieces of evidence used to define the start of the Anthropocene?
- The Colombian Exchange
- Atomic Weapons Testing
Describe the Colombian exchange
- New 🌎 species brought to Europe, Old 🌎 species taken to the Americas (the exchange)
- New diseases/bacteria viruses (e.g smallpox) killed around 50 million (90%) indigenous American —>huge areas of farmland abandoned
- forests grew + absorbed huge quantities of CO2 reducing CO2 amounts around the 🌎
- GLOBAL COOLING for 200 years (little ice 🧊age)
Describe the hypothesis of Atomic Weapons Testing
- USA ends WW2 by dropping atomic bombs on two Japanese cities —> as Cold War deepens = development of nuclear weapons
- Radiative material from tests enters atmosphere and spreads all around the world.
- Increase in radiation levels accumulates in sediment and bones/tissues of organisms
- Criticism - though recorded in sediment, impact was small, radiation levels higher than 1945 but within SAFE LIMITS
What is Anthropogenic behaviour?
The Anthropocene = man made climate change, human activity pushes Earth’s climate system beyond natural limits.
What is the Greenhouse effect (simple)?
A natural process that occurs when greenhouse gases in the atmosphere trap heat from the Sun, warming the Earth’s surface
Explain greenhouse effect
- 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
Percentage contribution of CO2, flurogases, methane and nitrous oxides in atmosphere and greenhouse strength (if co2 is 1)
CO2 = 75%, 1
Fluoro-Gases = 2%, approx. 10,000
Methane = 17%, 30
Nitrous Oxide = 6%, 600
Where did the CO2, Fluor-Gases, Methane and Nitrus Oxide come from?
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 🔥
Top 5 Countries responsible for global emissions and 3 common factors
- China
- USA
- India
- Russia
- Japan
- High populations,
- developed (or rapidly developing) economies, - abundant fossil fuel resources (coal, oil, gas)
Explain enhanced greenhouse effect and what increases the concentration of GG in armosphere.
- 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
How have atmospheric carbon dioxide levels changed over time (pre-industrial to present)?
pre-industrial (1800) = 280 ppm (part per mil.)
1958 = 310ppm
2020 = 410 ppm
(increased by 130ppm since 1800)
ROUGHLY 50%
Equation to work out % increase
% increase = final - initial/ initial (x 100)
Describe 5 pieces of evidence that demonstrate the Earth’s climate and natural systems are changing
(key word describe)
- Drought and Extreme Heat 🥵
- Positive Feedback loops 🔁
- Storms ⛈️
- Ice and Oceans 🧊 🌊
- Wildlife Ecosytems 🐼
What is a positive feedback loop and give some examples (melting permafrost in Arctic Tundra)?
- when something happens and in doing so causes itself to happen again more intensely (aka vicious cycle/snowball effect)
- ❄️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
Give another example of a positive feedback loop (wildfires in California)
- increased temperatures = more evaporation
- drier wood, easier to catch fire
- Autumn rainstorms, due to hotter climate, arriving later (extended summer)
- warmer at higher altitude = more pine beetles = weakened forest
- more dry wood and drought = less carbon sequestration
(CO2 emissions into atmosphere, melting glaciers -> rising sea levels and drier wood)
What is the “albedo effect” and give an example (glacier retreat due to wildfires)
- Albedo effect = the ability of a surface to reflect sunlight
- soot and ash from wildfires settles on the ice, darkening the surface and decreasing reflectivity (more ice melts)
What is “carbon sequestration”?
the process of capturing and storing atmospheric carbon dioxide
What is a ‘carbon footprint’ (CO2e) ?
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
How can you reduce your carbon footprint?
- Use public transportation
- eat local food and a plant-based diet (cheese, beef, lamb =ruminants that give off methane and less carbon intensive method of transportation)
- use energy-efficient appliances
- reuse and recycle old items
Who is most responsible for taking action against climate change?
Developed countries and rich countries in the WEST (largest emitters of CO2 ) must lead by example and move forward in a more SUSTAINABLE way.
How can governments make policies to mitigate against climate change?
- 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.
- 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
- promote plant based diets (less meat and dairy = less methane from ruminants)
- Invest in electric vehicles and reduce passenger air travel/aviation
OVERALL = renewable resources
What does “net zero” emissions mean?
net zero= the balance between the amount of GG produced and the amount removed from the atmosphere
