Environemnt Global Wamring Flashcards
Green house effect
1)Incoming short wavelength infrared penetrates atmosphere to reach the surface of the wreath
2) earth radiates longer wavelength infrared such as infrared
3) green house gasses in the atmosphere absorb some of this infrared and re-radiate in all direction and some becomes trapped within the earth atmosphere it back warming the earth
Define global warming
A measurable increase in the temperature of the earth atmosphere or temperature at the surface of the earth
Define climate
The average weather in a relatively large area over a long period of time
Define climate change
Large scale change in global or regional weather patterns that happens over a period of many years
Define weather
The condition in the atmosphere at a particular time of it is sunny or rainy when you go outside
Main sources of methane
Guts of ruminant animals
Landfill sites
Extraction of fossil fuels from underground
Rice paddy fields
Why have the CO2 been fluctuating
Volcanic eruption
Weathering of limestone rocks
Different season absorption of CO2
Frozen isotopes
Drill deep into ice core and analyze the trapped air in the core
( bubbles formed in ancient ice COEs)
The oxygen isotopes reflect the temperature at the time when the core was formed
Atmospheric carbon dioxide levels can also be formed from the core
Temperature records
Industrial revolution causes the atmosphere carbon dioxide to rise
Correlation of CO2 levels and temperature but not causation
But there is strong evidence that CO2 released by humans activities since the industrial revolution is causing an increasing global temperature
Dendrochrology
Using tree growth ring
Tree trunks grow in diameter each growing season as they produce more vascular tissue
—> measure of climate during each year of growth
What does the colour of the tree ring tell us
Rate of growth and season
What does the width of the tree tell us
Type of climate
Light tree ring
Fast
Warm spring summer
Optimal condition
Dark tree ring
Slow
Autum
Non optimal condition
Thick tree ring
Warmer and wetter
Thin tree ring
Cooler and dryer
What are peat bogs
Are partly decomposed plant material since peat is acidic , cool and anaerobic the organic material cannot be decomposed
How the peat be analysed
Peat builds up in layers and be taken from a bog and the layers can be analysed to assess the pollen grain that have become trapped in the peat
—> plant specie were growing around the bog at different points in time can be identified
—> plants present at different times can be used a measure of the climate at that time
What is computer modelling
Any attempt to predict climate change in the future must rely on very complex computer model to extrapolate from what we know to what might happen
In the graph extrapolation
Apply to already known trends to unknown situation to predict what will happen
Limitation of the extrapolation
Only approximation, no exact for particular area
Unknown factors in the future that are not included in the model
Risk of flooding
Rising temperature are causing glaciers to melt , the volume of water in the sea and ocean causing sea level to rise.
Water gets warmer it’s volume increases resulting in an even bigger impact on the sea level
—> may cause flooding this can harm animal , human and plants population causing vast decrease in world biodiversity
What increased atmospheric warming had on climate change
Weather events becoming more extreme eg hotter,longer, heatwaves, and more violent storms
Changes to oceans current leading to altered local climate eg the Gulf Stream that currently brings warm water to the west coast of the UK might change direction, causing parts of the UK climate to cool
Warmer air hold more moisture leading to changes in pattern of rainfall more heavier rainfall in some places could lead to reduced rainfall in other location
Warming climate causes animals to move toward the poles or to higher altitude
A concern is that these species may not be able to compete with, or may even out-compete, the species already present in these habitats, with either result leading to decreased biodiversity
Some species, such as plant species, may not be able to move or change their distribution fast enough to adapt to changing temperatures and may become extinct as a result
Water availability in some habitat is changing
Changes to rainfall patterns can be devastating to species that rely on seasonal rains for their survival e.g. some desert plants rely on rains that may come only once a year and climate change may mean that such seasonal events occur less frequently or stop altogether
Some species may no longer be able to survive in their habitat due to a lack of rainfall; such species may migrate to a new habitat or may become extinct
Seasonal cycles are changing
Plant species are producing flowers earlier in the year
Animals are producing young earlier in the year
Bird migratory patterns may lose their synchronisation with their habitats, leading to a change in migration patterns
E.g. earlier plant growth leads to alterations in invertebrate life cycles, meaning that when a bird species arrives for its summer migration their usual food source is not available
Polar ice and glaciers are retreating; it is thought that there may soon be no summer ice in the arctic if rates of warming there continue
The loss of glacier ice from mountain ranges may affect the water supplies of many people and surrounding wildlife
Sea levels have been rising faster in recent years, putting many more people and animals at risk of being flooded out of their homes
Sea levels are rising due to the expansion of warmer water and due to melting polar ice
Enzyme activity
Some chemical reactions take place faster at higher temperatures
Photosynthesis is essential for converting carbon dioxide into carbohydrates, the process which produces food for producers and other organisms higher up the food chain; it relies on the function of proteins in the electron transport chain and that of enzymes such as rubisco
E.g. blue-green algae, also known as cyanobacteria, photosynthesise at a higher rate in warmer water due to increased enzyme activity; this increases the formation of potentially harmful algal blooms
Some chemical reactions are slowed down at higher temperatures
At high temperatures plants carry out a reaction called photorespiration at a faster rate; this reaction uses the enzyme rubisco and so slows down photosynthesis
This can reduce crop yields as temperatures rise
Some fish eggs have been shown to develop more slowly at higher temperatures
Many species’ successful egg development is dependent on temperature, with impacts such as
Extreme temperature fluctuations can reduce hatching rates in some invertebrates
The sex of the young inside the egg of some species is determined by temperature, so increasing temperatures can affect the sex ratios in a species
E.g. in alligators
Species may have to change their distribution in response to changing temperatures in order to survive
Species may migrate to higher altitudes or further from the equator to find cooler temperatures
What does great changes in temperature can cause in tropical regions
Environment is relatively stable not like desert regions
(Less environment change -> less selective pressure —> less adaption
Big changes, the organism could be dead before adaption)
How does the temperature affect the changes in enzyme
Temperature changes —> enzyme activity—> plants —> animals then the ecosystem
How does temperature effect the enzyme activity
There is an optimum temperatures at which the enzyme works best , far away from that range and the enzyme will denatur3 no the rate of reaction would decrease.
If temperature increases then enzyme activity increases causing plants to grow and absorb more. O2 out of the atmosphere which decrease the conc of COW
If temperature are too high then animals and plants would die out
Temperature changes may cause selection pressure to some organism causing them to migrate or die out
Atmospheric carbon dioxide
Why have CO2 risen up
Since the industrial revolution has risen yo to the highest
Correlation vs causation
Data show the correlation between CO2 and temperature
—> carbon dioxide in the atmosphere is not thought to be the only factor but there is a strong evidence to suggest CO2 released by humans activities since the industrial revolution is causing increasing global temperature
How does peat work
Peat build up in layers
-top layers are more recently formed then peat at the bottom as you go down
Peat bogs accumulate in layers so the age of the preserve pollen increases with depth
What does the peat core tell us
Peat cores can be taken from a bog and layers can be analysed to assess the pollen grains that have been trapped in the peat
How can the climate be identified from pollen grains
Pollen grains from peat sample can be observed under a microscope and because the pollen grains of each plant specie are unique to that plant the plant specie that were growing around the bog at different points in time can be identified
What does a increase in pollen tell us
That more successful in warmer climate would show a rise in temperature
Different plant species grow under different climatic conditions so the plants present at different times can be used to measure of the climate at that time
An increase in the number of plants species that grow better in warmer climate combined with a decrease in the number of plant specie that grow better in cooler climates indicates a gradual warming of the climate
Causes of anthropogenic climate changes
The industrial revolution began in the late 1700s when the combustion of fossil fuels to power factories, transport, and homes became commonplace
Fossil fuel combustion releases carbon dioxide
A clear correlation can be seen between increasing levels of carbon dioxide since the industrial revolution and increasing global temperatures, providing evidence for the role of human activities in causing global warming
Note that a correlation alone is not enough to prove causation, but this evidence can be taken alongside what we know about greenhouse gases and other evidence to provide a growing body of proof
In addition to the burning of fossil fuels, carbon dioxide is also released into the atmosphere when natural stores of carbon are damaged or destroyed by human activities
These carbon stores are known as carbon sinks
Carbon sinks include trees, soils, peat bogs, and the oceans
Deforestation, soil degradation, peat harvesting, and ocean warming all contribute to the addition of carbon dioxide to the atmosphere
Carbon cycle
Carbon is present in the atmosphere in the form of carbon dioxide
Carbon dioxide is removed from the atmosphere by producers during photosynthesis
Producers incorporate carbon into their biomass in the form of carbohydrates and other biological molecules
Carbon is transferred to and between consumers as a result of feeding
Carbon is transferred back into the atmosphere by both plants and animals as a result of respiration
Respiration releases carbon dioxide as a product
Carbon dioxide can also be removed from the atmosphere by dissolving in the oceans
Dissolved carbon can be taken in by marine plants when they photosynthesise or by other marine organisms as they build calcium carbonate exoskeletons
When living organisms die their tissues are broken down by decomposers such as bacteria and fungi
When these organisms respire, they too release carbon dioxide back into the atmosphere
Any living tissue that is not fully decomposed can go towards the formation of peat or fossil fuels over millions of years; carbon can be stored in these sinks for long periods
The combustion of peat and fossil fuels releases carbon dioxide back into the atmosphere
The combustion of biomass such as wood also returns carbon to the atmosphere
Limitation of climate change prediction model
The IPCC has produced models based on several emissions scenarios, and we do not know which of these scenarios is most likely
I.e. we don’t know how successful humans will be at cutting greenhouse gas emissions
We do not know whether future technologies will be successful at removing greenhouse gases from the atmosphere e.g. carbon capture technologies may or may not be effective
It is unknown exactly how atmospheric gas concentrations might affect global temperatures
Global climate patterns are complex and therefore predictions are difficult
It is possible that a certain tipping point in global temperatures could lead to a sudden acceleration in global warming e.g. permafrost melting may cause a sudden increase in atmospheric methane
Permafrost is ground that is frozen all year round
We don’t know exactly how factors other than human activities may affect climate in the future e.g. a volcanic eruption could increase ash in the atmosphere, reflecting radiation back into space and cooling the earth
Limit of the model of future climate
1) we don’t know how green house gasses emission will change
2) we don’t know how much each emission scenario will cause the global temperature to rise by
3)The change in atmospheric greenhouse has concentration due to natural causes isn’t known
4)we don’t know what attempt there will be to manage the atmosphere concentration of green house bases or how successful they will be
Risk of flooding
Rising temperature are causing glacier to melt and sea levels to rise and in this case lands at Low sea level maybe flooded and this can harm animals humans and plant population causing a vast decrease in the world biodiversity
Warming of the climate cause the animals to move towards the poles
A concern is that these species may not be able to compete with, or may even out-compete, the species already present in these habitats, with either result leading to decreased biodiversity
Some species, such as plant species, may not be able to move or change their distribution fast enough to adapt to changing temperatures and may become extinct as a result
Water availability
Changes to rainfall patterns can be devastating to species that rely on seasonal rains for their survival e.g. some desert plants rely on rains that may come only once a year and climate change may mean that such seasonal events occur less frequently or stop altogether
Some species may no longer be able to survive in their habitat due to a lack of rainfall; such species may migrate to a new habitat or may become extinct
Seasonal cycle
Plant species are producing flowers earlier in the year
Animals are producing young earlier in the year
Bird migratory patterns may lose their synchronisation with their habitats, leading to a change in migration patterns
E.g. earlier plant growth leads to alterations in invertebrate life cycles, meaning that when a bird species arrives for its summer migration their usual food source is not available
Define evolution
When frequency of an allele in a population change over time it occurs by natural selection
Natural selection
1)individual within a population vary because they have different allele due to gene mutations
2) some individual that are better adapted to their environment than others
3) individual that have an allele that respe their chance of survival are more likely to survive and report and pass on their genes
4) there will be greater proportion of the next generation inherit the beneficial allele
5) so the frequency of the beneficial allele increase from generation to generation
Define allopathic speciation
That occurs when population become physically or geographically separated
Allopathic speciation process
1) population of individuals
2)physical barrier stop interbreeding and gene flow between population
3)population adapt to new environment
4) allele and phenotype frequency change leading to development of new specie
Define Sympatric speciation
Occurs when organism become reproductively isolated by behavioural , seasonal, mechanical changes
Define reforestation
The replanting of trees in an area where trees have been lost
Depend who reaches a conclusion
Find out whether the statement comes from a trustworthy, unbiased source e.g.
An individual working for an oil company or a particular government is likely to be biased because they have a financial or political interest in the outcome of a study
Several countries wrote to the United Nations in 2021 to ask that urgent recommendations against burning fossil fuels were toned down; all of these countries had economies that depended on the use of fossil fuels
An individual who campaigns passionately for conservation may be biased because they strongly believe that humans are causing climate change and they have an emotional stake in the outcome of a study
An individual who works for a renewable energy company may be biased because they are of the opinion that their technologies are better than fossil fuel technologies as well as having a financial interest in the outcome of a study
Support of biofuels
Biofuels are often cheaper than oil
It is argued that biofuels are ‘carbon neutral’ meaning that they only release carbon that was recently removed from the atmosphere when the plants were alive
They do not release carbon that has been stored away for millions of years as with fossil fuels
Biofuels are a renewable source of energy, i.e. they can be regrown quickly
Against biofuels
They do still release carbon dioxide into the atmosphere
The vast amounts of land required to grow biofuels could otherwise have been used for food production
Creating land for biofuel growth often involves the loss of other types of habitats e.g. rainforest; this is bad for biodiversity
Cutting down mature trees to create land for biofuel growth reduces the removal of carbon from the atmosphere by photosynthesis
Favour of renewable energy
These kinds of technologies are advancing quickly and are becoming cheaper and more efficient to use
No carbon dioxide is released when these technologies are used to generate electricity
Renewable energy disadvantages
Geothermal energy can only be used when there is volcanic activity close to the earth’s surface
Solar energy depends on sunshine hours
Wind energy depends on wind speeds and some conservationists are concerned about the impact of wind turbines on birds and bats
Some are also concerned about the visual impact of wind turbines on the landscape
Tidal energy can only be generated near the coast
Humans can increase photosynthesis by
Stopping the destruction of forests by deforestation
Planting trees, also known as reforestation
If trees are allowed to grow to maturity, they can store huge amounts of carbon in their biomass
Some countries around the world have shown that it is possible to restore lost areas of forest by carrying out reforestation, e.g. Costa Rica now plants seven times more trees than it cuts down
This kind of achievement requires huge government inputs in the form of benefits to landowners