Miss Loulousis
Began with careful observation Scientists in China began keeping records of earthquakes as early as 780BCE Maya tracked movements of the sun, moon, and planets Created calendars from observations Invention of microscopes and telescopes expanded understanding of the Earth revealing new things All discoveries up to this point made with unaided eye
Earth science is the study of Earth and of the universe around it. Like other sciences, assumes that the causes of natural events, can be discovered through careful observation and experimentation Branches: Geology- study of solid Earth Oceanography- study of the ocean Meteorology- study of Earth s atmosphere Astronomy- study of the universe
Geology study of the origin, history, processes, and structure of solid Earth Has many specialized areas of study Oceanography Oceans cover three-fourths of Earth s surface Some research waves, others currents or ocean floor
Meteorology Use satellites, radar, and other technologies to study atmospheric conditions that produce weather Some study climate-patterns of weather that occur over long periods of time Astronomy One of the oldest branches of Earth Science
Not a main branch, but still important These scientists study the way in which humans interact with their environment Relatively new field of science Study many issues such as use of natural resources, pollution, and health of plant and animal species on Earth Some study effects of industries and technologies on environment
Only known planet that has liquid water on its surface, and has atmosphere with large amounts of oxygen It is the only known plant to support life Earth is the 3 rd planet from the sun Formed about 4.6 billion years ago, made mostly of rock 71% of surface covered by thin layer of water called global ocean Oblate spheroid (slightly flattened sphere) shape Surface relatively smooth, with 20km between deepest ocean trench and tallest mountain
Knowledge based on indirect methods of study versus direct observation-seismic waves- have been helpful Earth made of 3 major compositional zones: Crust Mantle Core Earth made of 5 major structural zones: Lithosphere Asthenosphere Mesosphere Outer core Inner core
Outermost zone of Earth is the Crust Makes up 1% of Earth s mass Oceanic crust is only 5-10km thick Continental crust is ranges between 15-80km The mantle is the layer underneath the crust About 2,900km thick and makes up 2/3 of Earth s mass The Core, is the inner most layer of Earth About 3,500km in radius Made mainly of iron and nickel
Lithosphere-rigid layer 15-300km thick Cool and brittle Crust and uppermost part of mantle Asthenosphere-has solid rock with ability to flow, called plasticity Large amounts of heat and pressure Mesosphere-below the asthenosphere is a layer of solid mantle rock Outer core- dense liquid(2,900km) Inner core-dense, rigid solid (5,150km) Inner and outer core together make up 1/3 of Earth s mass
From studying earthquakes and the seismic waves they produce Monitoring waves can dive evidence of structure and consistency of the medium that they travel through Earthquakes produce 2 types of waves: P and S waves S waves do NOT travel through liquids P waves do travel through Liquids Both travel through solids
Earth has 2 magnetic poles, North geomagnetic pole and South geomagnetic pole Earth s magnetic field extends beyond the atmosphere into space, called the magnetosphere Scientists are unsure of the source of Earth s magnetic field Best hypothesis is the magnetosphere is caused by the liquid iron of outer core Could be a different source because sun and moon do not have large amounts of iron and both have magnetic fields.
Functions in protection of Earth from Solar winds. Similar to how your skin protects body from substances Sun sends out projection into space of plasma called coronal mass ejections Takes ejections about 3-4 days to reach Earth Earth s magnetosphere cause ejections to pass around Earth similar to how water goes around a stone Some slip in and can cause major disruptions to technology The interaction of the magnetosphere and solar winds causes auroras
Gravity- force of attraction between all mater in the universe Isaac Newton s Law of gravitation: the force of attraction between any two objects depends on the masses of the objects and the distance between them Larger masses=stronger force of gravity Small distance between objects=stronger force of gravity
Weight is a measure of the strength of the pull of gravity on an object Measured in newtons (N) Weight changes as the distance between objects change Mass is a measurement of how much matter an object has Measured in kilograms (kg) Mass does not change
Weight therefore can vary depending on location Weight is less near the equator and greater at the poles due to the distance between Earths core and the surface What does the difference in a person s weight at the poles versus the equator tell us about Earth s shape?
A. the thin and solid outermost layer of the Earth above the mantle B. The solid, outer layer of Earth that consists of the crust and rigid upper part of the mantle C. the strong, lower part of the mantle between the asthenosphere and the outer core D. the layer of rock between Earth s crust and core E. The central part of the Earth Below Mesosphere Crust Lithosphere Core Mantle What does the law of gravitation state?
System- an organized group of related objects that interact to create a whole All systems are linked Earth s system is a combination of two basic components: matter and energy Matter- anything that has mass and takes up space Energy- ability to do work
The Earth system is composed of four spheres which store the planet s matter Atmosphere blanket of gases surrounding Earth s surface 78%nitrogen, 21% oxygen 1% other gases Hydrosphere- the water that covers Earth, most of its in the ocean, about 3% is freshwater Geosphere-mostly solid part of Earth, all rock and soil on continents and ocean floor Biosphere- all life forms found on Earth and organic matter not decomposed
Definition- A set of events that repeats itself. EXAMPLES: Water Cycle, Carbon Cycle, Rock Cycle. The cycle will end where it started. Think of it as a merry-go-round. Cycles occur in one or more spheres. The cycles in turn affect the sphere and therefore the Earth System as a whole. MAINPOINT: ANY EVENT OR CYCLE THAT OCCURS IN ANY BRANCH OF SCIENCE AFFECTS EVERYTHING AROUND IT
Closed systems- energy is exchanged with surroundings, but not matter Example: a closed jar Contents of jar are stuck inside but heat, energy, light can still pass Energy has the ability to enter or exit but matter cannot enter or leave. Heat can pass in and out of the jar but more mass or less mass cannot occur due to the closed system If I were to tip the jar, the matter would still be in the jar therefore it is a closed system. But if I put it by the window it would gain and loose energy.
Open System-both energy and matter are exchanged with surroundings Example: an open jar An open jar of water would allow the water to evaporate. If I were to put something into the jar matter/mass would be added to the system.
What types of matter and energy are exchanged between Earth and space? Dust and rock come to Earth from space, while hydrogen atoms from the atmosphere enter space from Earth. IS Earth a closed or open system? Earth as a System is mainly closed because matter exchange is limited Earth is a CLOSED SYSTEM! small amount of rock and dust entering from space
A feedback loop is a mechanism by which change in a variable (example temperature) results in either an amplification (positive feedback) or a dampening (negative feedback) of that change
You get a rash from poison ivy. You know you shouldn't scratch it, but it itches. So you scratch. But scratching makes it itch more, and can even make the rash spread to areas that didn't itch before. The more you scratch, the more it itches. This is a positive feedback loop, because a change in the amount of itching is promoted or increased. Positive feedback loops like this are often called "vicious cycles.
The thermostat attached to an air conditioner helps maintain a constant temperature in your house. During the summer, the sun heats the house and the temperature goes up. When the temperature goes up, the thermostat turns on the air conditioner, causing the house to cool down. When the house is cool again, the thermostat turns the air conditioner off. This is a negative feedback loop, because temperature changes in the system are reduced.
First Law of Thermodynamics: energy is transferred between systems, but energy cannot be created nor destroyed So as energy is transferred through Earth s spheres there is a balance maintained (subtractions and additions always coinciding) Second Law of Thermodynamics: when energy transfer takes place, matter becomes less organized with time So matter spreads out more uniformly over time Matter cannot be created or destroyed
Total distribution of energy to, from, and between Earth s various spheres. Can you name some ways energy and matter are exchanged between spheres? Chemical reactions, radioactive decay, light, heat, growth, decay of organisms
Decay of radioactive atoms keeps Earth s interior hot Causes convection Hot materials from earth s interior moves to surface The heat from the interior is transferred and released at the surface Drives plate motions in geosphere creates mountains
The sun is Earth s most important external source Warms atmosphere and surface The heating generates winds and ocean currents by moving air masses Gravitational energy from moon and sun The pull of the sun and moon on the oceans along with earth s rotation creates tides
Energy and matter cycle through Earth s spheres Can be a short or long cycle Long cycle: carbon is stored in geosphere as a type of rock called carbonate Short cycle: Plants convert Co2 from atmosphere into carbohydrates Organisms break down carbs into CO2 or wastes Can you name any other cycles earth has?