The Earths Atmosphere Flashcards
(18 cards)
The atmosphere is
78 percent nitrogen
21 percent oxygen
0.04 percent carbon dioxide
Small amounts of other gasses eg water vapour and argon
Why did carbon dioxide dominate Earth early atmosphere
Highly active volcanos with frequent eruptions resulted in release of lots of co2
Why were carbon dioxide levels reduced?
Levels of nitrogen accumulated steadily
The oceans formed as a result of water vapour condensing, leaving to a significant reduction in co2 in the atmosphere as it dissolved in the oceans
Photosynthesis by algae and other organisms used carbon dioxide as a reactant therefore using it up and removing it from the atmosphere
Marine animals removed carbonates from the ocean as they used these to build there shells and skeletons
How did earth’s concentration of oxygen in the atmosphere increase
Algae was the first organism to photosynthesis
Then more began to evolve
As a result more and more oxygen produced from the c02 and water
Therefore more oxygen began to accumulate in the atmosphere
The process if the greenhouse effect
Sun emits short wavelength radiation that enters the atmosphere and travels towards earth
Earth absorbs part of this radiation but longer wavelength radiation is reflected back into the atmosphere
Greenhouse gasses can’t absorb the short wavelength radiation emitted by the sun but can absorb the reflected radiation
The gasses re radiate this as heat energy, some of which heads back to earth
This increases temperature at earth surface
What hunan activitys cause the concentrations of greenhouse gasses to increase
Burning fossil fuels releases carbon dioxide
Deforestation: less trees means less photosynthesis so less co2 is removed from atmosphere .
Landfill sights : numbers and sizes of these are increasing meaning more mounds of waste decomposing
Decomposition releases methane
Agriculture: animals releases methane during digestion, so as there’s more and more Agriculture more and more methane is released by livestock
Greenhouse gasses and climate change
Increasing greenhouse gasses will lead to global climate change
Some people have reasons to play down contribution of greenhouse gasses to global warming ( eg people in the factory’s)
This can lead to misinformation
Impacts of climate change
Melting ice caps will lead to rising sea levels, leading to flooding and erosion of coastlines
Some species like polar bears will be less successful hunters
Extreme events like storms heatwaves and droughts could increase in frequency and intensity
Change in water availability will effect how species are distributed
Changes in raining patterns could mean regions receive much more or less rainfall than usual, impacting wildlife
Food shortages is a combo of all the others as they all hinder a regions ability to provide
What is a carbon footprint
Measure of total amounts of greenhouse gasses emmited as a result of a particular service product or event
How can carbon footprint be reduced
Minimising our waste
Using renewable energy resources
Imposing emission based taxes
Emmisons licences to a certain cap
Examples of decreasing our carbon footprint
Carbon capture and storage - capturing co2 produced by fossil fuels before it passes into the atmosphere. The stores are kept underground
Carbon off setting : counteract emissions by planting trees which remove co2 via photosynthesis
Carbon neutral products: don’t change atmospheric co2 conc
Factors that make reducing carbon footprints harder
Scientists don’t agree on causes and consequences of climate change, preventing them from making advancements
Many governments worry that making required changes may restrict to economic development of the country
Mostly in developing countries
Countries have different opinions about the right course of action, which spreads uncertainty therefore country’s hesitate to sign anything
People may not want to change their lifestyle
People are not educated about climate changes significance
Common atmospheric pollutants from fossil fuels
Incompete combustion( burning in insufficient oxygen) - 2 by products are carbon monoxide and particulates ( small solid particles containing carbon and unburnt fuel)
Sulphur impurities- when burnt leads to sulphur dioxide
Internal combustion engines in cars- when fossil fuels are burnt in a confined space high temps cause nitrogen and oxygen to react making toxic nitrogen oxides
Properties of carbon monoxide
Binds hemoglobin to blood restricting bloods availability to transport oxygen around the body
Odourless and colourless so difficult to detect
Symptoms from exposure range from fainting to fatality
Properties of particulates
Inhaling them casues respitory issues
Reflect incoming radiation out into space leading to global dimming which decresses levels of sunlight fir photosynthesis
Properties of sulphur dioxide
Inhaling it causes respiratory issues
Reacts with water to form sulphuric acid
Sulphuric acid is a part of acid rain, causing erosion and death of insects plants
Nitrogen oxides
Inhaling can cause respiratory issues
Reacts with water to form nitric acid which is also a key component in acid rain
4 main atmospheric pollutants
Nitrogen oxides
Sulphur dioxide
Particulates
Carbon monoxide
