C6.3 - Earth Systems Flashcards
Done
describe the theory of how the atmosphere was originally formed
- intense volcanic activity released gases (like CO2 and water vapour) = formed early atmosphere
- as Earth cooled, water vapour condensed - it fell as rain to form oceans
- leaving an atmosphere of mostly carbon dioxide
-probably with small amounts of
ammonia, methane - BUTlittle/no oxygen
what kind of gases did the volcanoes release in the early atmosphere?
- huge volumes of water vapour
- carbon dioxide
[[- small amounts of nitrogen ]???ignore]
how has an oxygen-rich atmosphere developed over time?
- plants and algae made their own food through photosynthesis
- took in carbon dioxide + water and released oxygen
Carbon dioxide + water —> glucose + oxygen
describe the four steps of the greenhouse effect
1) energy transferred by radiation from Sun reaches Earth’s surface
2) radiation warms up the earth’s surface
3) Infrared radiation is emitted by the earth’s surface
- some goes directly into space
- some is absorbed by greenhouse gas molecules in the atmosphere
4) greenhouse gas molecules emit infrared radiation in all directions, warming the Earth’s surface and atmosphere
ENHANCED GREENHOUSE EFFECT
what human activity increases levels of greenhouse gases in the atmosphere?
- for CO2 (1) + methane (4)
- combustion of fossil fuels (release CO2)
- rice paddy fields, cattle farming, landfill waste sites, use of natural gas (methane)
what evidence causes uncertainty that human activity is contributing to climate change?
- will lead to global climate change (not a specific area)
- so is difficult to model (very complex system)
- causes simplified models (and media, opinions based on only some parts of evidence)
FIRST effect of increased levels of carbon dioxide + methane on earth’s climate
- causes an enhanced greenhouse effect
- increasing the temp. Of the Earth’s atmosphere — increase in average global temperatures
how can greenhouse gas emissions be reduced? (3)
- reduce consumption of fossil fuels, for example by using BIOFUELS
- renewable energy resources, i.e. wind/solar energy to generate electricity
- stopping carbon dioxide escaping when fuels are used by using CARBON CAPTURE
Carbon monoxide? - produced how
+ 2 examples
- produced during incomplete combustion of fuels that contain carbon
- can happen when coal, wood, natural gas are burned in a poor supply of air
- also in vehicle engines
Describe carbon monoxide?
…. gas
features
- is a toxic gas
- has no colour, taste smell
3 examples of fossil fuels
Coal, oil, and natural gas
problems of increased amount of sulfur dioxide? 2
- causes acid rain
- breathing difficulties
oxides of nitrogen?
- formed where
- then?
- called what?
-nitrogen and oxygen, the main gases in air, do not normally react together
- nitrogen major gas in air reacts with oxygen at high temperatures in vehicle engines, forming nitrogen monoxide NO
- this is then oxidised in air to form nitrogen dioxide, NO2
- these oxides of nitrogen are jointly called NOx
What happens with nitrogen dioxide
- nitrogen dioxide dissolves in the moisture in clouds, forming an acidic solution, which eventually falls as acid rain
what is the problem with acid rain?
- erodes stonework + corrodes metal
- can kill trees
- can kill living things in rivers/lakes
main source of particulates in atmosphere?
- produced in industrial processes like metal extraction
- incomplete combustion of fossil fuels
- in vehicle engines
what are particulates?
How they produced? (2)
- small particles
- produced in industrial processes such as metal extraction
- like CO, they are also produced during incomplete combustion and in vehicle engines
problem caused by increased amount of particulates in the atmosphere
[- global dimming?ignore?]
- small particles settle deep in lungs, when they are breathed in
= diseases e.g. bronchitis + other breathing problems; also increases chance of heart disease
where does tap water come from originally?
- water stored in lakes, reservoirs
- or in aquifiers
- from rivers/waste water
7 main steps in water treatment, from reservoir to potable water
1) as water enters the water treatment works, it passes through screen (metal bars placed close together which trap large objects like leaves + twigs)
2) passes through settlement tank (where soil + sand settle out)
3) aluminium sulfate + lime added to the water (causes small particles of dirt to clump together + sink to bottom)
- the sludge that collects like this is dumped in a landfill site where it forms mud
4) water passed through a filter made of fine sand (removes remaining particles of mud/grit, so water is clear)
5) chlorine added to kill bactera
6) pH checked + corrected so that it is neural
- the water is then stored in large tanks and service reservoirs, ready to be pumped to homes/schools/offices/factories
what is groundwater?
water found underground in cracks/spaces in soil/sand/rock
where is groundwater stored (and where and how does it move)?
- stored in geological formations of soil, sand, rock
- moves slowly through aqufiers
? WHO CARES ?
where is salt water found?
sea water
what is the name of the process used to treat salt water?
desalination
how to treat salt water on a small scale?
- ‘reverse osmosis’ using ‘ultrafilters’ used to filter out the salts
how to treat salt water on a large scale?
For large scale desalinisation, simple distillation is used
what factors would affect whether desalination would be worthwhile in a country?
(and give an example where they use it)
- where freshwater supplies are limited
- or where the cost of energy resources is low
- ie. coast on middle east
what characteristics must water have to make it potable?
- low levels of microbes
- low level of contaminating substances
what does it mean if water is potable?
safe to drink
3 most abundant gasses in atmosphere today
Nitrogen (78), oxygen (21), Argon (0.9%)
Carbon dioxide (0.04)
What happened to the atmosphere, as a result of plants and algae appearing?
- photosynthesis reduced the amount of carbon dioxide in the atmosphere
- it also released oxygen
What did the oxygen from the plants + algae do over time
- at first, the oxygen reacted with metals in rocks to produce metal oxides
- later, as most of the metals became oxidised, free oxygen began to accumulate in the atmosphere
- eventually, the oxygen-rich atmosphere that you have today developed
How carbon dioxide disappeared into oceans?
Carbon dioxide is a very soluble gas. It dissolves readily in water. As the oceans formed, carbon dioxide dissolved and the amount of it in the atmosphere decreased.
From - 3 most abundant to here
🏠
What is the greenhouse effect in2 sentences - incl, its purpose
- greenhouse gases such as carbon dioxide and methane absorb infrared radiation radiated by the earth’s surface, then emit it in all directions
- this greenhouse effect keeps the Earth and its atmosphere warm enough for living things to exist
Name 3 greenhouse gases
Carbon dioxide, methane and water vapour.
Potential EFFECTS of global warming (3)
- melting ice caps
- rising sea levels
- and climate change
Effects of climate change
- altered weather patterns
= flooding/droughts - problems with farming and disease control
Anthropogenic meaning
(chiefly of environmental pollution and pollutants) originating in human activity
The extra carbon dioxide is causing an enhanced __ effect, greater than would happen naturally. There is a __ between the increase in atmospheric carbon dioxide concentration, and t__ change. As the concentration of carbon dioxide has increased, the global a__ temperature has generally increased too.
The extra carbon dioxide is causing an enhanced greenhouse effect, greater than would happen naturally. There is a correlation between the increase in atmospheric carbon dioxide concentration, and temperature change. As the concentration of carbon dioxide has increased, the global average temperature has generally increased too.
SO WHATS THE ISSUE with the steps to reduce greenhouse gas emissions
- but what else?
- such steps are expensive (biofuels, renewable energy resources, carbon capture)
- but so are steps to protect against the effects of global warming
In the meantime, there are ways to mitigate the effects of climate change. These include: (4)
- building flood defences to manage floods from rivers and seas
- designing buildings to withstand high winds
- planting different crops, better adapted to a new climate
- building irrigation systems to provide water in droughts
Problems with steps to mitigate effects of climate change - 3
These steps are expensive, need to be on a large scale, and may themselves harm the environment.
— water
🚿 🚿 🛁
Water from all the sources (lakes, reservoirs, aquifers, rivers, waste water) contain what (3)
- microorganisms
- insoluble materials such as leaves, and particles from rocks and soil
- soluble substances, including salts, and pollutants such as pesticides and fertilisers
- most of these must be removed at treatment works to make the water safe to drink
Why must desalination be done
- seawater contains high concentrations of dissolved salts
- to make this water potable, these must be removed in a process called desalinisation
Treating seawater
Seawater contains too much dissolved salt to make it suitable as drinking water. However, pure water can be produced from seawater by simple distillation.
The seawater is boiled and the water vapour is then cooled. It condenses to form pure water, leaving the salt behind.
CON + PRO
It is expensive to produce drinking water this way because large amounts of energy are needed to heat the seawater.
However, water produced by distillation is useful in the laboratory for dissolving substances. It does not contain any dissolved ions that might interfere with a chemical analysis.
—— pollution + the atmosphere—-
🌌 🌌 🌌
Pollutants vs atmospheric pollutants (how released)
- pollutant are substances released into the environment that may harm living things
- atmospheric pollutants are released into the air — many of them are released as a result of burning fossil fuels
4 examples pf atmospheric pollutants
- carbon monoxide
- particulates
- oxides of nitrogen
- sulfide dioxide
WHY carbon monoxide bad - examples + WHy
- when breathed in, CO attaches to the haemoglobin protein in RBCs = reduces amount of oxygen that bloodstream can carry
- causes drowsiness/difficulty breathing/even death
What do many homes have. - because of carbon monoxide
Carbon monoxide monitors - sound an alarm if faulty gas boilers or cookers produce carbon monoxide
PM10 particles?
- PM10 particles are 10um or less
- there is a link between their concentration in air and health problems
3 examples of fossil fuels
Coal, crude oil, natural gas
What do fossil fuels naturally contain
- and what does this form
- Fossil fuels (coal, crude oil, natural gas) naturally contain small amounts of sulfur compounds
- these impurities form sulphur dioxide when the fuel is burnt
Problems with sulfur dioxide (2)
- causes acid rain
- can cause breathing difficulties
Hydrocarbonfuels can undergo complete combustion or incomplete combustion, depending on the amount of oxygen available.
Complete combustion happens when there is a g__ supply of air. Carbon and hydrogen atoms in the hydrocarbon fuel react with oxygen in an exothermic reaction:
- c__ dioxide and w__ are produced
- e__ is given out
Carbon dioxide is an atmospheric p__. Incomplete combustion produces other pollutants.
Hydrocarbonfuels can undergo complete combustion or incomplete combustion, depending on the amount of oxygen available.
Complete combustion happens when there is a good supply of air. Carbon and hydrogen atoms in the hydrocarbon fuel react with oxygen in an exothermic reaction:
carbon dioxide and water are produced
energy is given out
Carbon dioxide is an atmospheric pollutant. Incomplete combustion produces other pollutants.
Incomplete combustion
Incomplete combustion happens when the supply of air or o__ is poor. Water is still produced, but carbon m__ and c__ are produced. Less e__ is released than during complete combustion.
For example, here is one possible equation for the incomplete combustion of propane:
propane + oxygen → carbon + carbon monoxide + water
C3H8 + 3O2 → C + 2CO + 4H2O
Incomplete combustion
Incomplete combustion happens when the supply of air or oxygen is poor. Water is still produced, but carbon monoxide and carbon are produced. Less energy is released than during complete combustion.
For example, here is one possible equation for the incomplete combustion of propane:
propane + oxygen → carbon + carbon monoxide + water
C3H8 + 3O2 → C + 2CO + 4H2O
Salt water treated using reverse osmosis?
Pressure is applied to salt water where it then passes through a partially permeable membrane where only water molecules can pass through.
Filtered water remains.
