Impacts Of Climate Change Flashcards
What is the melting of ice causing and give an example
Water stored as ice returns to the oceans
Greenland and Antarctic ice sheets
What does water returning to the oceans mean there is an increase of and what does it lead to
What is this called
Volume of the water in oceans increases
Causing sea level to rise
Eustatic sea level change
If all remaining ice sheets were to melt, how much would global sea level increase by
60-80 metres
What does increased global temperatures mean and what does it cause
Oceans get warmer and expand
Causes thermal expanse which also increases the volume of water leading to further sea level rise
How much could the sea levels rise for an increase in global temperature of 1degrees
8-80cm
What is global warming causing
Ice to melt
Permafrost to thaw
Other changes in climate
What are prediction of how much sea level will rise in the future like
Uncertain and differ a lot
What does IPCC stand for, who are they and what do they do
Intergovernmental Panel on Climate Change
Group of scientists
Look at the risks of climate change
What do the IPCC think
Sea levels could rise by 18-59cm by the end of the century
Any rise in sea level will have a local/regional/national/global impact
(Which one)
Global
Will the impact of sea level rise be the same everywhere
It will be greater in some places than others
Explain how sea level rise would affect Bangldesh
80% of land area is low lying - any sea level rise will submerge large areas
Would affect lots of people as it has a high population density (1,000 people per km2)
Would be made worse as it is an LIC - vulnerable population with low capacity to cope
Explain how sea level rise would affect the Maldives
Extremely low lying set of islands I’m Indian Ocean - rise of 0.5cm would submerge most of the country
Population not poor but economy is dependent on tourism, which would be threaded by sea level rise
What is permafrost
Ground that has been permanently frozen for two or more years - covers around 20% of the Earth’s land surface
What are areas of permafrost
Natural sinks of CO2
- stored as organic material in the soil
- thawing releases some of this, contributing further to global warming
What could thawing of permafrost lead to
Buildings to collapse and pipelines on it
-may also bring economic benefits though -eg easier to look for/extract natural resources (fossil fuels) in areas of unfrozen ground
What do changes in global temperatures affect
Global weather patterns
- Increase in frequency of extreme weather events -eg increasing in ocean temperatures may mean an increased risk of tropical cyclones over a wider area
- Change in the distribution of climatic regions -eg colder polar regions may shrink and warmer tropical regions may advance to higher latitudes
What does a change in global temperature and weather patterns affect
The ecology (distribution/abundance of organisms) - species will have to migrate to remain in a sustainable climate, if they cannot migrate they will become extinct Agriculture -eg some areas become unsuitable for cultivation as climate factors (temperature and the timings of seasons) alter
Example of a benefit that regional climate changes may bring to some human activities
Economic benefits of tourism where climate has become hotter
What are emissions scenarios used for
To predict impacts of global warming
What is the scientific consensus of what is causing global warming
Human factors (eg CO2 emissions)
How do scientists try to predict the impact of climate change
By predicting how emissions will change in the future
What are the emissions scenarios the IPCC have produced
Predictions of how human CO2 emissions will change up to 2100
What are the scenarios
Emissions not increasing much more (scenario 5)
Emissions continuing to grow as they are now (‘business as usual’)
Emissions increasing a lot (scenario 1)
Emissions being controlled by sustainable management strategies
What do the IPCC put all the different scenarios into to see how much the climate would change with each scenario eg. how much global temperature will rise
Global climate models
What will the different scenarios also show other than how the climate would change
Different climate changes will cause different impacts eg. different levels of sea level change
Scenario 2: rise by 0.23-0.51m
Scenario 3: rise by 0.21-0.48m
Scenario 4: rise by 0.18-0.38m
Reasons why it is difficult to predict the impact of climate change
So much uncertainty:
1. Do not actually know how emissions will change, ie. which emissions scenario is accurate
2. Do not know how of the emissions will be absorbed (eg. natural carbon sinks)
3. Extent of climate change due to natural causes (without human influence) is unknown
4. Do not know what climate changes each emission scenario will
cause
5. Do not know what attempts there will be to mange the impacts of climate change or how successful they will be
What might combined impacts lead to
Tipping point
What is the tipping point
Where a slight rise in temperature would cause catastrophic and irreversible changes to the environment, creating a much more hazardous world
What might the tipping point occur because of
May happen because of the positive feedback loop - where a change in climate is speeded up by impacts already caused
Example of positive feedback loop
Global warming causes melting of Arctic sea ice
As ice melts it leaves darker sea water in its place
Sea water has a lower albedo (amount a surface reflects the Suns radiations) than ice
Therefore more radiation is absorbed by the water
Warm water, then causes more ice to melt, etc
Example of combined effect of positive feedback on several of the impacts of global warming
Ice melt and the destruction of CO2 sinks, may lead to a tipping point
