Assignment 3 MXB100 PDF

Universe Terms-TRM 4 - Exam wk7 or wk8 - Multiple choices - Short and long responses [Key Words] **Space-** Everything outside of the Earth's atmosphere **Universe-**Is made up of all existing matter and space considered as a whole; the cosmos Includes: Planets, Moons, stars, galaxies a...

Universe Terms-TRM 4 - Exam wk7 or wk8 - Multiple choices - Short and long responses [Key Words] **Space-** Everything outside of the Earth's atmosphere **Universe-**Is made up of all existing matter and space considered as a whole; the cosmos Includes: Planets, Moons, stars, galaxies and all matter and energy **Galaxies-** a system a millions or billions of stars, together with gas and dust, held together by gravitational attraction yet separated by space. The galaxy that we are apart of is called the Milky way-200 billion stars -There are 1500 galaxies **Light Years-** The distance light travels in 1 year. Light travels at 300,000km per second which ius the equivalent to travelling 9.46 trillion km 1 year **Travelling at the speed of light would take:** 1.3 seconds to reach the moon 8 minutes to reach the sun - The nearest star to the earth (other than the sun) is 4.2 light years away - The nearest galaxy to the Milky Way is 2.5 million light years away - The Milky Way is 100,000 light years across **Solar System** All the planets that revolve around out sun M=Mercury V=Venus E=Earth M=Mars J=Jupiter S=Saturn U=Uranus N=Neptune **Stars** A star is a luminous sphere of plasma held together by its own gravity The sun is the star at the centre of the solar system. It is nearly perfect sphere of hot plasma. Due to its huge gravity, it keeps all the planets in the solar system orbit. **Planet** A planet is a larger body than an asteroid or comet, lit by light from a star, such as the sun, around which it revolves. **Earth** The earth (otherwise known as the world, in Greek or Latin, Terra) is the third planet from the sun and the densest planet in the solar system. It is the largest of the solar system's four terrestrial planets, and the only astronomical object known to harbor life. **Moon** The Mood is Earth's only permanent natural satellite Natural satellite or moon is an astronomical object that orbits a planet **Nebulas** Nebula is dense clusters of gas and dust which can be observed using the light of the stars around them **Comet** A comet is a small icy body that, when passing close to the sun, heats up and begins to outgas, displaying a visible atmosphere or "Tail" **Asteroid** An Asteroid is a small rocky body orbiting the sun. large numbers of these, ranging enormously in size, are found throughout the universe **Supernova** A supernova is an astronomical event that occurs during the last stellar evolutionary stages of a massive star's life, whose dramatic and catastrophic destruction is marked by one final titanic explosion. For a short time, this causes the sudden appearance of a 'new' bright star, before slowly fading from sight over several weeks or months **Blackhole** A blackhole is a region of spacetime exhibiting such strong gravitational effects that nothing-Not even particles and electromagnetic radiation such as light -can escape from inside it **Big Bang Theory** A theory in astronomy that the universe originated billions of years ago in a rapid expansion from a single point of nearly infinite energy density **Astronomy** Astronomy is the study of celestial objects (such as stars, galaxies, planets, moons, asteroids, comets and nebules), processes, and evolution of such objects and processes, and more generally all phenomena, and more originate outside the atmosphere of earth. **Telescopes** It is above the Earth's atmosphere it produces image 10 times better than those from telescopes on earth It can see objects 100 times further away **2/10/2024** **The Big Bang Theory** The broadly accepted theory for the origin and evolution of our universe is the big bang theory, which states that the universe began as an incredibly hot, dense point roughly 13.7 billion years ago [Misconception on the Big Bang theory] - There was no explosion; there was (and continues to be) an expansion - Space began inside of the singularity. Prior to the singularity, *nothing* existed, not space, time, matter, or energy-nothing [Big Bang theory Timeline] 1. **Time begins** The universe begins 13.7 billion years ago A violent [explosion] All matter and space were created from a single point of pure energy in an instant - 0.000001 seconds-The rate of expansion slows, but the universe becomes less dense and cool. The first gravity comes into effect and then the force, which holds the nuclei of atoms together - 1 second- all the subatomic particles have been created 2. **3 minutes after the big bang** E=mc^2^ Energy frozen into matter Energy forms matter into clumps (Protons, neutron and electrons) 3. **Several hundred thousand years later** Atoms form (specifically hydrogen and its isotopes with a small amount of Helium) Early universe was about 75% hydrogen and 25% Helium. Still the same to this day **Predicted timeline** [10000 years]- The universe continues expanding and cooling and radiation waves (x-rays, gamma rays) are stretched into microwaves and light rays [300000 years]- Atoms begin to pick up electrons and more simple elements are created. Protons and neutrons start to combine to form the first simple atoms (hydrogen, helium, lithium) [300 million years-] pockets of gas start to condense into the earliest stars and galaxies 4. **200 to 400 million years** 1^st^ star and galaxies form 5. **9 billion years** The sun forms within a cloud of gas in a spiral arm of the milky way galaxy. A vast disk of gas and debris that swirls around this new star gives birth to planets and moons (one of which is earth) 6. **4.6 million yeas ago-** solar system was formed 7. **10 billion years** The earth has cooled and an atmosphere develops. Microscopic living cells, neither plants nor animals, begin to evolve and flourish in earth's many volcanic environments 8. **13 billion years ago** Primitive animals in the form of flatworms, jellyfish and algae appear 9. **13.5 billion years ago** The first mammals evolved from a class of reptiles 10. **13.635 billion years** The dinosaurs become extinct 11. **13.6994 billion years** Homo sapiens evolve **Summary-** Bing Bang theory snapshot - **Big bang theory-**energy/ expansion - Matter - E-mc^2^ - Protons - Neutrons - Electrons - Atoms - Hydrogen - Helium - Stars and galaxies - Our solar system - Sun and all planets - Earth (present day) - **Stars** are very large balls of mostly hydrogen gas, which produce large amounts of energy, through **nuclear fusion**, over an extended period of time. - Conditions in certain parts of the universe have allowed stars to form - A star's brightness depends on how close it is to Earth, but also on how big the star is. - Stars come in various colours depending on how hot they are. Blue stars are the hottest, white and yellow next, and red the coolest - [Brightness]- considers how large the star is (its magnitude) - [Colours]- depends on the temperature of the star - 1.989 x 1030 kg - 1.409 g/cm^3^ - 4.6 billion years Composition: - 92.1% hydrogen - 7.8% helium - 0.1% other elements Temperature: - 5,500 degrees **The surface of the sun** - Sunspots are temporary darker spots on the surface of the sun that are reduced temperatures - Solar flares are big emissions of energy (ejection of electrons and atoms) from the surface of the sun - The gases ejected from the surface by the solar wind impacts on earth forming auroras and interferes with radio communication **Nuclear Fusion** - The sun's energy is produced by **nuclear fusion** whereby the nuclei of hydrogen atoms are fused together to create helium, releasing large amounts of energy - **Nuclear Fusion** is the process by which two or more atomic nuclei join together, or "fuse", to form a single heavier nucleus - **E.G H + H = He** **Hertzsprung-Russel diagram** - Shows the relationship between a star's temperature and its luminosity - Used to chart a star's life cycle - Once stars exhaust their fuel, they become red giants or white dwarfs **Life cycle of a star** - Prostar -\> main sequences -\> red giant -\> white dwarf/ black dwarf -\> supernova-\> neutron star or black hole - Stars about the same size as our sun initially glow very brightly, the settle into middle-life period of about 10 billion years - Sun has 5 billion years left **Birth of Stars** 1. Stars are born in clouds made of hydrogen gas 2. Gravity pulls the gas molecules into dense cloud 3. This dense cloud develops its own gravity, which begins pulling in more gas and dust from the cloud, increasing the mass and gravity of the dense cloud 4. The centre of the dense clouds becomes tightly packed causing the molecules to bump into each creating heat 5. As the heat increases the cloud begins to glow, this is known as a **Prostar** 6. Once the temperature reaches 10,000,000 degrees the star begins to shine, and a new star is born    **Life cycle of the sun** - Very large stars start in very massive clouds of gas and dust - All stars are born in **Nebulae**-massive clouds of gas and dust in space **Red Giants** - Once the hydrogen in the star s used up it begins to swell, and its surface gets cooler - It is called the red giant because it is red in colour and has swollen to a much bugger size as its core has shrunk **White Dwarf** **Black Dwarf** - Eventually the white dwarf stops giving off light and heat and becomes a black dwarf **Supernova** - Once a star expands to a greater size, the reactions will stop occurring and will collapse on itself, which produces an explosion called a **Supernova** - How minerals such as silver, gold and iron came into existence **Betelgeuse** - 642.5ly away - Any change in the star will ONLY be seen 624.5 years after it takes place **Two outcomes for supernovas** 1. The core of the star is pulled inwards by gravity to form an incredibly dense, small star called a **Neutron star** 2. When massive stars (our sun x10) explode, the core collapses in on itself and keeps collapsing. This create a **Black hole** **Neutron star** - A neutron star of very small and very high density composed predominantly of closely packed neutrons - If the star is insufficiently massive it will not produce a black hole **Black Holes** - Some of the biggest stars are 3 times bugger than our sun - When these stars collapse, the star is reduced to a point smaller than a needle, with high amounts of gravity - The gravity is so big, that even light can't escape from this point - **Blackholes-** Points in space made by the death of huge star, which have huge amounts of gravity and pull matter into them and prevent even light from escaping **9/10/24 Star Spectra** Which star would be the closest? -The closest star in this image would be the **white** star. This is because it is [much larger in the picture] that has been taken, yet they are the same **size**. This would indicate that it is closer to earth in comparison to where the blue star is located in the universe. The white star is **brighter** which would indicate that it is closer. Based on knowledge of the light spectra, the blue star would be the **hottest as blue stars** range from [40,000 -- 10,000 degrees], whereas white stars can range from [10,000 - 7000 degrees] **Exploring spectra analysis** One of the ways in which astronomers study distant stars, nebulae gas/dust clouds and other celestial bodies is by the use of spectral analysis They analyse the visible spectrum using equipment such as a *spectroscope* Newtons was one of the early scientists to experiment with glass prisms to diffract visible light into its component wavelengths for analysis A similar effect can be seen when light passes through a soap bubble or water droplet to produce a rainbow **Spectra of stars** White light is made up of all the colours of the rainbow. It can be split into its colours by a prism or a spectroscope. This produces a spectrum with blue at one end, red at the other and all the other colours in between. Red stars produce more red light than any other colour, and blue stars produce more blue light. Astronomers have also found that the spectrum of a star has thin dark lines along it as shown below, as if some parts of the spectrum are missing. These lines are like the lines when seeing a hot gas through a spectroscope   **Stars have cooler gases around them which absorb certain colours. So when the light from a star reaches Earth these colours are missing from its spectrum. If there is a dark line where the yellow sodium line should be, people can infer that the star contains the element of sodium. So the absorption lines in the spectra of stars are like fingerprints for the various elements.** **Star Spectra** -The spectrum (spectra in plural form) in this case is a graph of the amount of light given off by something. It is divided into wavelengths -By looking at these wavelengths we can tell the colours of the star and their brightness. These are not visible to the naked eye.   Instead of seeing a continuous spectrum there are absent wavelengths. These are absorption lines in the spectrum -These are caused by a specific electron jump. This absorbs a specific wavelength of light. When able the electron will release the energy and drop back down. It will be the same wavelength as before. -The colours (wavelengths of light) emitted and absorbed correspond with both the energy level of the electron and the element involved   ** **A diagram of light by hydrogen Description automatically generated -We can use a lowing nebulas emission spectrum to find out what gases it is made of based on the colour it is emitting. We are also able to do this with its absorption spectrum -An element spectrum is like a fingerprint -Different elements have different spectra because they have different numbers of protons, electrons and neutrons in their atom -Can also determine the temperature and density of those elements in a star from its spectra -Can also discover the magnetic fields of the star, how fast the material is moving -To summarise, can find out what celestial bodies are made of an atomic level, its temperature and its intrinsic luminosity  **Red shift** -in 1920, Edwin Hubble first noticed that galaxies moving away from the milky way galaxy were emitting more reddish light than expected. He had noticed red shift : **the shift of spectral lines in the absorption spectra towards the red end of the visible spectrum** Later, Hubble used red shift as evidence stars were moving away from our galaxy and as evidence for an expanding universe **Note: the 'red shift' and 'blue shift' are not the same as a change in the colour of an object. Changes in overall colour are very slight for shifts within our galaxy and in nearby galaxies. These changes are detectable in spectroscopes rather than being visible.** **15/10/2024 Evidence for the big bang** 1. Redshift of galaxies 2. Microwave background 3. Mixture of elements 1. **Red Shift** -The light we observe from galaxies has been stretched by time it reaches us and as a result it looks redder than it should -The redshift is the result of galaxies moving away from us (blue is moving towards -The universe is expanding which follows the idea that logically conclude that everything once was in the same place 2. **Cosmic Microwave background (CMB)** -In the 1960s scientists found that background radio emission was coming from every direction in the sky-both day and night-and this glow was a few degrees above zero -This is because over time and expansion, the universe has cooled from being very hot to quite cold -This discovery supports the Big Bang theory as it predicts that this glow should exists and should be detectable as microwave light -The CMB is the remnant of that earliest at the beginning of time -This supports the theory as it predicts the glow should exist and be detected by microwave light -The CMB began as very hot and energetic photons in early universe and was emitted into the atmosphere 13.7 billion years and since it has been expanding and cooling to -273 degrees -No observable space outside of CMB, because it is the first thing to be emitted after the universe became transparent -Universe became transparent when plasma was able to form into first atoms -matter was too dense for light to travel freely -At this time there were also no stars or galaxies in existence -Any star or galaxy that we have observed has been inside the background radiation -The 'fossil' radiation, the furthest that any telescope can see, was released soon after the big bang. Considered as an echo or 'shockwave' of the big bang **Steady State Theory** - The universe is always expanding but maintaining a constant average density, with matter being continuously created to form new stars and galaxies at the same rate that old ones become unobservable as a consequence of their increasing distance and velocity of recession. - The law of conservation of mass among other things disproved this theory - Elements like hydrogen and helium were examples of chemical creations after the big bang. The big bang theory predicts how much of each element was made in the early universe. When astronomers look at very old galaxies and stars, the amount of each chemical they see agrees with the Big Bang Theory. - Cannot look for this in new stars. This is because they contain old elements made from older stars, so the chemical make-up of new stars is very different from stars which existed soon after the big bang  A diagram of a plasma structure Description automatically generated with medium confidence **Elements** \- The relative abundance of light elements like hydrogen and helium, which make up almost 100% of the elements available, supports the big bang theory through nucleosynthesis -[Nucleosynthesis is the process of creating new atomic nuclei at a very high temperature] \- all hydrogen and majority of helium has emerged from this process   **16/10/24 Global system, earth science** [Earth's sphere's] **The outside of the earth has four main components** - **Atmosphere** - **Hydrosphere** - **Biosphere** - **Lithosphere (the outer rocky surface)** - **cryosphere** **Called 'spheres' because they are roughly the size and shape of earth** **Lithosphere** The lithosphere contains all hard solid land of the planet's crust (surface) **Hydrosphere** The hydrosphere contains all the solid, liquid and gaseous water of the planet **Atmosphere** The atmosphere contains all air in the earth's system **Biosphere** The biosphere contains all the planet's living things. This sphere includes all of the microorganisms, plants, and animals of earth. [Analysing interactions between spheres] For plants, matter comes from the atmosphere, the lithosphere and hydrosphere in the form of carbon dioxide, soil nutrients and water. For animals, matter and energy inputs are often in the form of plants or prey from the biosphere, or as oxygen and carbon dioxide from the atmosphere, when they breathe in and out. +-------------+-------------+-------------+-------------+-------------+ | SPHERES | Lithosphere | Hydrosphere | Atmosphere | Biosphere | +=============+=============+=============+=============+=============+ | Lithosphere | Ocean | Hurricanes | Hurricanes | hurricanes | | | basins | | | | | | | Tsunami's | Tsunami's | | | | Continents | | | | | | | Erosion | Volcanoes | | | | Volcanic | | | | | | | Wave action | Wave action | | | | eruptions | | | | | | | tectonics | earthquakes | | +-------------+-------------+-------------+-------------+-------------+ | Hydrosphere | waves | Wave action | El nino | Photosynthe | | | | | | sis | +-------------+-------------+-------------+-------------+-------------+ | Atmosphere | Ozone | El nino | winds | Ozone | | | change | | | change | | | | Ozone | | | | | | change | | Photosynthe | | | | | | sis | +-------------+-------------+-------------+-------------+-------------+ | biosphere | | photosynthe | photosynthe | Predator-pr | | | | sis | sis | ey | +-------------+-------------+-------------+-------------+-------------+ **18/10/2024 Climate & sphere** **Weather** is the conditions of the present time; sunny, rainy, windy, snowy etc. and temperature. Weather is [based on hour to hour or day to day observations] **Climate** is the average temperature and rainfall [over a long period of time**.** ]Generally averages recorded over at least a 30 year period **Climate is what we expect and weather is what we get** -Each season is approximately 3 months long **[Temperature]** -Air is heated indirectly from the earth's surface, by heat energy. -This energy is absorbed by naturally occurring greenhouse gases (ghg) such as water vapour and carbon dioxide **[Heating liquids and gases]** -**convection currents** occur when heat is transferred by the mass movement of particles in a fluid. Thye are very important for the atmosphere because of its influence. -Can occur in a gas such as air -Also in liquids such as water -Convection currents affect winds and ocean currents -If occur in water affect the hydrosphere -The transfer of heat between the hydrosphere and atmosphere can change conditions in the atmosphere **[Hydrosphere: Surface ocean currents]** -upper 10 m of ocean water is moved by prevailing winds -Areas of warm water have a higher rates of evaporation (and potentially more rain) than areas of cold water **[Rainfall]** -Determined by % of water vapour -Warm air can contain more water vapour than cold air -Condensation occurs when temperatures fall and relative humidity is high **[Influences of climate:]** interactions between the atmosphere and the hydrosphere result in weather and climate (then has an impact on biosphere) **[The Greenhouse effect]** The **greenhouse effect** is a natural process that warm's the earth's surface. Sun's energy reaches the earth's atmosphere and some is reflected back to space and the rest is absorbed and re-radiated by greenhouse gases **[Climate data]** [ ] This climate graph summarises the monthly temperature and precipitation (rainfall). [\[CHART\]]{.chart} [\[CHART\]]{.chart} **22/10/24 Human Impacts on sphere**   +-------------+-------------+-------------+-------------+-------------+ | **Sphere​** | **Lithosphe | **Hydrosphe | **Atmospher | **Biosphere | | | re​** | re​** | e​** | ​** | +=============+=============+=============+=============+=============+ | **​** | ** Wells:** |  **Aquifers |  **Greenhou |  **Isolatio | | | ​ | :**​ | se gases:** | n:**​ | | **​** | | | ​ | | | | CSG wells | Each gas | | Residents | | **​** | are | well | CSG wells | do not | | | dug hundred | drains mill | and affecte | have anywhe | | **​** | s | ions | d | re | | | of | of litres | bores | to go as | | **​** | metres deep | of water | emit methan | they either | | | in | over its | e | do not want | | **​** | the earths  | lifetime. T | gas, | to move or | | | crust & | his | which is | cannot.​ | | **Environme | can | takes away | highly | | | ntal affect | be spaced | bore water | flammable a | ​ | | ​** | as little | for | nd | | | | as 400m | livestock | toxic.​ | **Rights:** | | | apart.​ | and familie | | ​ | | | | s.​ | ​ | | | | ​ | | | Stress to | | | | ​ | **Toxic | rightful la | | | **Pipes:**​ | | fumes:**​ | ndholders | | | | **Toxic | | against mul | | | Large pipes | waste:**​ | Compressor | tinational  | | | are laid to | | stations em | companies c | | | pipe the | Salty water | it | ourt | | | gas to | and carcino | and | action | | | export | genic | bleach gase | which | | | markets whi | waste | ous | affects | | | ch | are stored | fumes | a persons h | | | can | in huge | into the | ealth​ | | | be 3m deep | ponds that | atmosphere. | | | | and | are not | ​ | ​ | | | stretch for | disposed of | | | | | 1000's |. | ​ | **Health:** | | | of kilometr | This may | | ​ | | | es. ​ | leech | | | | | | into ground | | People | | |  ​ | water | | having gas | | | | sources | | wells sunk | | | | or contamin | | near there  | | | | ate waterwa | | homes | | | | ys. ​ | | are exposed | | | | | | to | | | | | | significant | | | | | |  amounts | | | | | | of toxic | | | | | | chemicals​ | +-------------+-------------+-------------+-------------+-------------+ **Leaching** The leaching process is used in the extraction of substances from solids. This is achieved by dissolving the given substances in a liquid. This can be done via an industrial process or even through a natural process. Leaching removes vital nutrients and micronutrients from the soil In mining, lots of different products are mined using leaching   **23/10/2024 Human impacts on the sphere** -other metals were found with the uranium at Rum Jungle. The graph below shows many tonnes per year of copper, manganese and zinc were leached out of the mine site.   There are both economic benefits and environmental consequences to coal seam gas mining +-----------------------------------+-----------------------------------+ | Economic benefits | Environmental impacts | +===================================+===================================+ | -Royalties to state governments | -Is toxic to aquatic life and | | | habitat | | -Trade partners around the world | | | | -terrestrial organisms are affect | | -Multinational corporation | due to the water quality that | | profits | they intake | | | | | -Jobs/employment | \- | | | | | -Energy source | | +-----------------------------------+-----------------------------------+ 1. Tailings are the leftover material from processing mined ore -in this case, "sandy waste carrying sulphur, heavy metals and radioactive materials." 2. When tailings mixes with oxygen and water it makes acidic mine drainage which contains acids radioactive material and ither bad things. This seeps from waste rock into the nearby area causing the ecological destruction of the area. Lots of plants and animals in his died out in the Finniss River area **25/10/2024 The carbon cycle**   Carbon is an element that is vitally important to life one earth because it is a major building block for many important molecules. All animals and plants contain carbon The movement of carbon into and out of these stories is called the **Carbon cycle** **Natural factors to carbon cycle** -Photosynthesis -Fire -The burning of fossil fuels -weathering -Volcanism **Human factors that affect carbon cycle** -Burning fossils -Changing land use -Using limestone to make concrete **Earth as a closed system** -The earth is a closed system where materials such as carbon, cycle between the lithosphere (earth), atmosphere, hydrosphere, and biosphere -Carbon travels through this closed system [Inputs] -An input is a component that moves into a defined system -e.g. CO~2~ moving into a plants leaf through photosynthesis [Outputs] -An output is a component that moves out of a defined system -E.g CO~2~ being released from burning coal Plants absorb **Carbon dioxide** from the atmosphere and turn it into **glucose** during photo synthesis Animals eat the plants for the energy in **glucose** and then release **carbon dioxide** back into the atmosphere during respiration **Photosynthesis** Carbon dioxide + water -\> glucose + oxygen **Respiration** Oxygen + glucose -\> carbon dioxide + water **5/11/2024 Sea level & biodiversity**  Effects of sea level rises -With around 85% of Australia's population living in the coastal zone, rising sea levels and storm surge will have a significant impact on many of our coastal towns -There are many other risks to a range of organisms, ecosystems and biomes from sea level rises. [Monitoring and understanding sea level rises] -The sea level is rising at an increasing rate largely due to man made global waming -The two major causes of global sea-level rise are: -**Thermal expansion** caused by warming of the oceans (since water expands as it warms) -**Loss of land based ice**, such as glaciers and ice sheets, due to increased melting **Threats to Australian Biodiversity** -Climate is predicted to take place faster in the next century. Coupled factors, such as continued land-clearing, this could mean extinction of species at a rate even greater than the dinosaurs disappearance -Some species not under immediate threat of extinction might nonetheless suffer decrease in population size, diminishing intra-species' genetic diversity (therefore face increased vulnerability) -[**Biodiversity**] is the variability among living organisms including the diversity within species, between species, and of ecosystems [Temperature spikes] **-**a number of species will be affected physiologically by climate change. There is evidence that [some species are physiologically vulnerable to temperature spikes] **Coral bleaching & ocean acidification** -[Warmer sea surface temperatures are blamed for an increase in a phenomenon called **coral bleaching**] -[**Ocean acidification** poses yet another challenge for corals because it makes it hard for corals to build their skeletons] **Increase in extreme events** Changes in the intensity, frequency and extent of disturbances such as fire, cyclone, drought and flood will place existing vegetation under stress and favour species able to rapidly colonise denuded areas **Changes in rainfall** Australia is a dry continent, even minor changes in rainfall patterns could have major impacts on wildlife -Predicted decreased rainfall and consequent lower river flows in both regions would have a major impact on aquatic biota **Increased CO~2~ and plant growth** -Increased carbon dioxide in the atmosphere causes increased growth rates in many plant species -this is good news for farmers, but only if this carbon dioxide 'fertilisation' effects is matched by adequate soil moisture and other nutrients **Sea-Level Rise** -Sea level is predicted to ride by 26-98 centimetres by 2100, due to the thermal expansion -World's ocean are crucial to heating earth -Most of the sun's heat is absorbed by the oceans -Warmer waters around the equator retain heat that warms the earth -The earth's atmosphere retains heat by the greenhouse effect -Oceans