Global Systems Flashcards
Water cycle effects on spheres
Atmosphere: precipitation, condensation, transpiration, evaporation
Lithosphere: percolation, evaporation, transpiration, run off
Hydrosphere: all
Earthquakes effect on spheres
Lithosphere: cracks and movement causing mud and landslide, destroying ecosystems and habitats.
Causes liquification (when soils loose their structure and act as liquid).
Atmosphere: little effect
Hydrosphere: create tsunamis in the ocean, create floods by breaking dams, change cause of river
Volcanoes effect on the spheres
Atmosphere: creates lightning with ash particles and water vapour, ash clouds block sunlight having a cooling effect, Hydrosphere: Sulfur dioxide from volcano in atmosphere makes acid rain, effects water ways and characteristics of water with toxins
Lithosphere: can create mountains and islands and also make them disappear
Biosphere: lava burns plants and animals, toxic gases from ash suffocate animals
Cyclones effect on spheres
Develop as low pressure systems in warm tropics over the sea, build and spiral inland
Hydropshere: heavy rains causing floods, storms, increases sea level, movement of salt water across low lying areas, destruction/ creation of rivers
Atmosphere: winds, dust, debris, intense low pressure system
Lithosphere: erosion, sediment in river, uproot trees, destroy habitats
How does the water cycle allow for interactions between the spheres
Water moves through the three phases (gas, liquid, solid) over the four spheres in a cycle. It allows the water to change state and exchange it between spheres.
How does the nitrogen cycle allow for interactions between the spheres
Nitrogen cycles throughout the spheres in different states. All living things need nitrogen. It allows the spheres to interact as nitrogen moves from the non living to the living in a connected cycle through the spheres.
Nitrogen cycle effect on spheres
Atmosphere: atmospheric nitrogen, denitrifying bacteria, lightning
Lithosphere: nitrogen fixing bacteria, ammonium, nitrates, decomposers, plants, denitrifying bacteria
Hydrosphere: eutrophication, nitrifying bacteria in soil under water, plants, decomposers,
Natural disasters effect on built environment
Destroy homes, buildings, towns, cities, roads, cars, boats, kill people
Climate
Long term averages of weather conditions (over 30 years)
Weather
Short term localised atmospheric conditions
Surface of the earth - influence on climate
Characteristics of the earth’s surface determine how much of the Suns energy is reflected back into space. Clouds and ice reflect most of the Suns energy (84%), dark forests are unable to reflect as much (14%) and instead absorb the energy. If the earth was all forest it would be a lot warmer
Gases in the atmosphere - influence on climate
Energy coming from the sun is short wave radiation that gets absorbed by clouds and the earth’s surface and radiated back as long wave radiation. Oxygen and nitrogen make up most of the atmosphere and have no effect on this radiation. Other gases in the atmosphere - water vapour, CO2, methane, nitrous oxide and ozone allow the short radiation in but absorb the out going long wave radiation and they re-emit the heat in all directions. Some radiated back to earth’s surface. The gases trap the heat close to the earth’s surface warming it and having a greenhouse effect. These are called greenhouse gases. Without them, the earth’s ave. temp. would be -18°C, not 15°C.
Orientation of the earth - influence on climate
The earth is roughly spherical. It orbits around the sun on a tilted axis of 23.5°. This tilt causes some parts of the earth to be closer to the sun and others to be far away creating the seasons
Ocean currents - influence on climate
Ocean currents are continuous movements of water that determine the climate of many of earth’s regions. Caused by: wind, temperature, salinity, earth’s axis and gravity. Surface currents are caused by wind and occur in a circular pattern called gyres. Deep currents began at the poles with very cold water along the bottom of the ocean. Surface and deep currents interact. As water heats it rises to the surface and sinks as it cools, forming the thermohaline or global conveyor belt. Takes 1600yrs to complete. It distributes heat and precipitation around the globe and regulates global climate.
Evaluate the evidence for human activity creating substantial wastes and the impact of this on the spheres - evidence
Evidence: increase in land fill, higher amount of packaged goods (plastic, shopping, food, wrapping), more pollution, demand for products with population growth, land used for buildings - land, farming and dumping waste, oil spills and use of fossil fuels
Evaluate the evidence for human activity creating substantial wastes and the impact of this on the spheres - atmosphere
Atmosphere: increase in CO2, lower levels of oxygen, higher acidity in atmosphere, depletion of ozone layer, acid rain, high level of organic pollutants
Evaluate the evidence for human activity creating substantial wastes and the impact of this on the spheres - hydrosphere
Changing ph, high turbidity - death of organisms, death of coral, destroyed food chains, high salinity, low dissolved oxygen, toxins in water, plastic and rubbish in water killing animals , polluting water
Evaluate the evidence for human activity creating substantial wastes and the impact of this on the spheres - lithosphere
Erosion, removal of vegetation, soil compaction, land fill, desertification, high salinity
Evaluate the evidence for human activity creating substantial wastes and the impact of this on the spheres - biosphere
Removal and destruction of habitats, plastic and waste in water ways, killing animals, in organisms food sources
Evaluate the evidence for human activity depleting the ozone layer
Ozone (O3) occurs in the stratosphere in what is called the ozone layer. It absorbs UV radiation. The use of products produced by humans containing various combinations of chlorine, fluorine, bromine, carbon and hydrogen deplete ozone molecules, thinning the ozone layer and allowing UV radiation in. Products have been used in refrigerators, air conditioning, foam blowing, cleaning and electronics. Eg: CFCs but have now been band. Evidence gathered from satellite imaging, ozone measuring tools showed hole size increase linked to CFCs manufacture. The hole was at its largest in 2000 with a volcanic eruption but is on the mend with the reduction of ozone depleting chemicals
Global warming
A time when the average world temperature is increasing. This occurs during interglacials - periods between glaciations where ice caps melt causing sea levels to rise. Evidence of the rise and fall of sea level is seen in the patterns of sediments and fossils in coastal rocks. Reasons for the last periods of cooling and warming of the earth are not fully understood. Therefore it is hard to fully assess the contribution humans have to the current period of global warming which started 200 000 years ago.
Evidence for climate change
Glaciers, ice cores, pollen analysis, sea level change
Glaciers
Glaciers: advance when climates are cool and retreat when climates are warm. When they advance they drag and score rocks across the valleys they run through and leave a moraine when they retreat
Ice cores
In some glaciers and ice sheets, enough snow has fallen each year to form layers. Cores can be taken out revealing different layers. By analysing the physical and chemical properties of each layer, we can discover the temperatures, composition of air and levels of CO2 from hundreds of thousands of years ago.
Pollen analysis
Pollen decays slowly and often becomes fossilised. Fossils indicate the species living in the area at the time when the sediment that made the fossil was laid down. Changes in the type of pollen found indicates a change in climate and vegetation
Sea level change
The world wide distribution of sedimentary rocks and the types of fossils found in them indicate that there have been changes in sea level in the past. Eg: sea creature fossils have been found in central Australia.
Human induced vs natural cause of climate change
Naturally occurring factors cause climate change, ocean currents, atmospheric gases, earth’s tilt, volcanoes, the sun. Human activities such as agriculture, urbanisation, deforestation, population growth, fossil fuels, industrialisation have had a more widespread influence on effecting the worlds climate than natural causes.
Evidence for humans creating climate change
The earth is warming and being polluted due to human causes. 2000-09 was the warmest on record. The enhanced greenhouse gas effect is an increase in the natural greenhouse gas effect caused by human activity. Increase in CO2, methane, nitrous oxide. Graphs show a drastic rise in CO2 levels over the last decade. Evidence in ice cores, sea level change, pollen etc
Evidence against humans creating climate change
No evidence. In a intergracial period and global warming is expected, the earth will cool again after this period. Measurements of climate have been taken for little more than a century, trends that drive climate change occur for a lot longer than that - difficult to identify the exact effect of changes by humans
Carbon dioxide in the atmosphere
Largest source is decay of organic matter, this is balanced by natural carbon sinks that remove carbon from atmosphere. Evidence of CO2 in atmosphere came from ice cores before measurements started in 1957. 8000 years ago, CO2 in atmosphere was 20 ppm, now 391 ppm in 2010. Coal and gas are major carbon sinks. When these are burned for energy it releases carbon dioxide into the atmosphere.
Evaluate the evidence for human activity enhancing the greenhouse effect
Greenhouse effect caused by greenhouse gases. Natural
occurring, although human activity leads to an increase of these gases and the enhanced green house effect
How do humans produce methane
Methane: formed from breakdown of organic matter, produced in stomachs of cows and sheep. Agriculture, farming, coal mines, gas fields, garbage tips, permafrost (bubbles of methane trapped in arctic wetlands) methane is released. Can trap 20 times more heat than CO2
How do humans produce CO2
CO2: burning of fossil fuels & coal for energy, electricity, cars,oil
How do humans produce nitrous oxide
Nitrous Oxide can trap 300 times more heat than CO2. Produced in car exhaust, through industrial processes, burning of forests and use of nitrogen based fertilisers
Importance of ice
Ice reflects Suns rays creating a cooling effect, ice acts as a blanket reducing the amount of heat that moves from the ocean to the atmosphere, water at the surface absorbs CO2 acting as a pump that takes CO2 out of the atmosphere and into the deep water currents. Without this the earth would be a lot warmer. Salt water doesn’t freeze. Ice is fresh, leaving the water with high salinity when ice is formed. Creates denser water which sinks to the bottom to the deep water currents. Changes in amount of ice could change global currents and climate.
Loss of ice, rise in sea level
There is an increase in global temperatures Due to the enhanced green house effect. This is causing ice to melt, break off from Antarctica and glaciers are sending it out into the ocean. The ice is melting and the sea is rising. Increase in temp. also leads to warmer waters. Warm water expands making sea levels rise
Biodiversity
The variety of ecosystems in the biosphere, the variety of species within those ecosystems and the genetic variation in the species.
Evaluate the evidence of human activity leading to increased rates of extinction
As the climate heats up and there is a loss of biodiversity, food sources and habitat, this increases the rate of extinction. Caused by pollution, deforestation, urbanisation, industrialisation, extreme weather events, greenhouse gas, pollution, population growth. Creating loss in habitat, ecosystems, resources, food, biodiversity. Organisms can’t surviveOver 14000 species threatened, 16000 endangered. In the last 500 years, humans forced 800 species into extinction. Extinction rate 1000 times higher than background rate.
Evidence of human activity leading to loss of biodiversity
Species may die out due to the earth’s changing climate. Urban development and land clearing destroys habitats and divides ecosystems making it hard for organisms to survive and move to a suitable place to live. This reduces biodiversity having a huge effect on all ecosystems and spheres. Deforestation, urbanisation, over population, pollution
Biodiversity loss and change examples - coral
Coral can’t cope with a rise in even 1-1.5° warmer temps. Causes coral to become stress and expel the protists which give the coral colour and nutrients. Coral becomes bleached and may not recover. Can no longer compete with the algae that grows and the reef is taken over by algae growth. Organisms rely on coral for food and shelter, effecting the whole ecosystem
Biodiversity loss and change examples - Australian Alps
Kookaburras are hunting on skinks in higher altitude. Skinks don’t recognise the birds as predators and the skink population is decreasing. Wallabies are moving further up to graze on the herb fields. Won’t survive continuous grazing, loss of biodiversity
Biodiversity loss and change examples - long spined sea urchins
Moving south to Tasmania where it could harm the ecosystems due to rising sea temperatures carrying the larvae south.
Human activities affecting increasing carbon
Burning fossil fuels, deforestation, agriculture, urban development, burning waste, landfills, livestock
Carbon cycles through the spheres on earth through
Fossilisation, photosynthesis, respiration, weathering, decomposition, combustion, dissolving of co2 in solution, feeding relationships, formation of carbonates
Photosynthesis and respiration and carbon
Plants absorb co2 from the atmosphere through photosynthesis. Some is returned to the atmosphere immediately through respiration
Decomposition and carbon
All living things contain carbon. When they die and decompose, carbon is released into the atmosphere
Fossilisation and carbon
Dead organic matter can be fossilised storing the carbon. This is also the same with trees and wood
Combustion and carbon
Burning fossil fuels, coal or wood releases long stored carbon into the atmosphere
Weathering and carbon
Carbon in the atmosphere can cause acid rain. This effects weathering, eroding rock and sediments quickly
Dissolving of co2 in solution and carbon
Photosynthesis and respiration that occur in plants under the water
Feeding relationships and carbon
When animals eat plants they convert some of the carbon from the plant into the tissues of their bodies. Some is returned to the atmosphere through respiration and some is added to the soil in manure. Also cycling of carbon through food chain
