Water, Carbon And Life On Earth (mainly Climate Change) Flashcards
(14 cards)
What is a positive feedback loop in the carbon cycle?
1 . High levels of greenhouse gases in atmosphere causes global temperatures to increase
2. Increasing temperatures cause permafrost to thaw
3. Thawing exposes previously frozen organic matter to decay
4. As organic matter decays it releases co2 and sometimes methane into atmosphere
5. Atmospheric co2 and methane levels increase
Cycle repeats
What is a positive feedback loop in the water cycle?
- Warmer atmosphere can hold more water vapour
- Water vapour is a greenhouse gas
- Warming of the climate system
- increased evaporation of water from earth’s surface
Cycle repeats
What is a negative feedback loop in the water cycle?
Input:
1. Increased co2 in atmosphere
2. Increased greenhouse effect and warmer temperatures
3. Increased evaporation from oceans
Output:
4. Increases cloud cover and albedo
5 Decreased temperatures
6. Back to equilibrium
What is a climate feedback loop
Can be both positive and negative
Positive:
Global warming
Creates change
Speeds up warming
Negative:
Global warming
Creates change
Slows down warming
What are the impacts of climate change on life on earth?
The global precipitation pattern expected to change – wet areas expected to get
wetter and dry areas are expected to get drier, could cause water shortages in some areas, which could lead to conflict in the future. (eg The Sahel, Africa) a region experiencing increasing water shortages and desertification putting pressure on local communities and animals.
Extreme weather events expected to get more frequent - includes storms, floods and
droughts. Although these will affect all continents, less developed countries will probably be worse affected - less able to deal with the impacts. Countries eg) Philippines.
Agricultural productivity is expected to decrease in some areas - could lead to food
shortages. Prices of major crops likely to increase, poorest suffering most. Eg) Sub-Saharan Africa likely to be vulnerable.
Sea levels expected to rise further - flood coastal and low-lying areas, increase rates of coastal erosion. Area at risk include low-lying islands e.g. Maldives and densely populated countries in SE Asia, eg) Vietnam, Bangladesh, Japan. In Europe a number of countries with low-lying, crowded coastlines are at risk, eg)
The Netherlands, the UK and Ireland.
The geographical range of some species will change - arrival of new species in an area may damage the ecosystem, some species may become extinct, e.g. polar bears.
Plankton numbers may decline if temperatures increase - which will have a knock-on effect on marine food changes.
Explain how Carbon Capture and Storage (CCS) can mitigate climate change
A technology that can capture up to 90% of carbon emissions produced from the burning of fossil fuels, preventing it from entering the atmosphere.
First, CO2 is captured and separated from other gases. It is then compressed and transported by pipeline or ship to a storage location.
At the location it is stored deep underground in rocks several km below the Earth’s surface.
Although the technology is proven some environmental campaigners criticize its cost and the fact that it is linked to increased oil production. CO2 injection is used to force oil and gas out of rock, which
helps pay for the CCS.
Explain how afforestation can mitigate climate change
increase carbon uptake by the biosphere
Trees act as carbon sinks, removing CO2 through photosynthesis and storing it within their biomass or the soil.
Trees also release moisture into the atmosphere and help moderate the Earth’s climates.
Explain how carbon farming can mitigate climate change
Using farming methods that reduce greenhouse gas emissions and/or capture and hold carbon in vegetation and soils:
Some crops absorb more carbon than others.
One type of crop can be replaced by a more productive one that will absorb more CO2 from the atmosphere
Reduced or no Ploughing avoids accelerated decomposition of organic matter and depletion of soil carbon.
Crop rotation with pasture or a cover crop increases biomass returned to the soil
Explain how renewable energy can help mitigate climate change
Governments can reduce reliance on fossil fuels for heating and powering homes by increasing the availability and reducing the cost or renewable energy such as wind, solar and tidal.
Explain how international agreements on emissions can mitigate climate change
Countries can work together to reduce emissions.
For example, the Paris Agreement (2015) an international treaty to control the total amount of greenhouse gases released.
Participating countries agree to keep their emissions within set limits.
In reality, the treaties are very hard to enforce, everyone has to agree and limits are often exceeded.
Explain how carbon trading schemes can mitigate climate change
A type of international agreement.
Countries and businesses are given a limit on the emissions they can produce.
If they produce less they can sell the extra credits, if they produce more they need to buy more credits
Explain how increasing energy conservation and efficiency can mitigate climate change
People can choose to use their cars less and buy more energy efficient cars.
Homes and businesses can also be made more energy efficient e.g. with double glazing, insulation and more efficient appliances.
Planners can increase the sustainability of developments e.g. by improving public transport and creating more green spaces.
Climate change adaptation strategy
Drought resistant crops - specially adapted to be able to survive harsh conditions expected to become more frequent as a result of changing precipitation patterns caused by climate change
These adaptation strategies can be put in place more quickly than waiting for carbon levels to be restored and so more beneficial in the short term.
Allows communities to better withstand climate change while longer mitigation strategies are put in place.
Helpful in vulnerable countries eg) Maldives as carbon mitigation strategies may not be fast enough to prevent irreversible damage.
What is a negative feedback loop in the carbon cycle?
increased atmospheric CO2 leads to both warmer temperatures and availability of CO2 for uptake by plants This promotes increased photosynthesis rates and carbon capture/storage by plants
reducing the carbon levels back to state of balance
