Chapter 1: Earth as a Chapter 1: Earth as a SystemSystem

Chapter 1.1Chapter 1.1

A New View of EarthA New View of Earth

Past Perceptions Meet Past Perceptions Meet New IssuesNew Issues•Scientist in Earth Science use to Scientist in Earth Science use to

specialize, one would steady the specialize, one would steady the rocks on a mountain while another rocks on a mountain while another study the water and another life study the water and another life forms.forms.

•Today Scientists realize that Earth is Today Scientists realize that Earth is more than a collection of parts. more than a collection of parts. Earth System Science is the study of Earth System Science is the study of and interaction of all parts.and interaction of all parts.

The rise of Earth System The rise of Earth System ScienceScience

•Came about due to advances in Came about due to advances in TechnologyTechnology– Satellites, deep diving subs, Satellites, deep diving subs,

geographic information systemsgeographic information systems

•Better models to represent Better models to represent objects, processes and objects, processes and phenomenon.phenomenon.

What is a system?What is a system?

• It’s a kind of model that can be defined as part of It’s a kind of model that can be defined as part of the universe that can be studied separately.the universe that can be studied separately.– Include time as a variable – figure future or Include time as a variable – figure future or

pastpast

• Closed System – something enters but can’t leaveClosed System – something enters but can’t leave– Sun tea – the closed jar doesn’t share matter Sun tea – the closed jar doesn’t share matter

with its surroundings.with its surroundings.

• Open Systems – the system and its surrounding Open Systems – the system and its surrounding freely exchange both energy and matterfreely exchange both energy and matter

• Earth System Science – scientists study the flow Earth System Science – scientists study the flow of energy and matter between the components of of energy and matter between the components of the Earth System.the Earth System.

A Planetary SystemA Planetary System

•Earth is considered a closed Earth is considered a closed system. However, it is not system. However, it is not entirely closed. The atmosphere entirely closed. The atmosphere looses hydrogen atoms to space looses hydrogen atoms to space and meteorites enter the earth.and meteorites enter the earth.

•Considered closed because the Considered closed because the resource of earth are finite resource of earth are finite (limited)(limited)

Nature, Science and Nature, Science and Human PolicyHuman Policy•Changes humans are making after Changes humans are making after

realizing their impact on Earth.realizing their impact on Earth.– RecycleRecycle– Environmental concerns before growthEnvironmental concerns before growth

•Flagstaff AZ ---waterFlagstaff AZ ---water

– Not easy to balance human needs and Not easy to balance human needs and wantswants

– Global warmingGlobal warming– OzoneOzone– Water and air pollutionWater and air pollution

Chapter 1.2Chapter 1.2

The Earth System’s Four The Earth System’s Four SpheresSpheres

•The four systems interact The four systems interact continually affecting the others.continually affecting the others.

AtmosphereAtmosphere

• It’s the gaseous envelop that It’s the gaseous envelop that surrounds the Earth.surrounds the Earth.

• It provides oxygen, CoIt provides oxygen, Co22, ozone, water, , ozone, water, vapor, clouds, rains, and snow.vapor, clouds, rains, and snow.

• It is the only atmosphere in the solar It is the only atmosphere in the solar system to contain free oxygen.system to contain free oxygen.

GeosphereGeosphere

•Made up of all physical features on Made up of all physical features on the planet except waterthe planet except water– Rock, mountains, beaches, rock layers, Rock, mountains, beaches, rock layers,

ocean basins, mantle, core, volcanoesocean basins, mantle, core, volcanoes

HydrosphereHydrosphere

• Contains all the water on Earth’s surfaceContains all the water on Earth’s surface– Liquid, gas, iceLiquid, gas, ice

• Most of Earth’s water is salty.Most of Earth’s water is salty.

• Only 3% is fresh of that 70% is in the Only 3% is fresh of that 70% is in the form of ice.form of ice.

• Only ½ of 1% is usable fresh water.Only ½ of 1% is usable fresh water.

• All water is recycled. The water you All water is recycled. The water you drank today may have been some of the drank today may have been some of the same water a dinosaur drank before.same water a dinosaur drank before.

BiosphereBiosphere

• Includes all living things on Earth Includes all living things on Earth even people.even people.

Interactions among the Interactions among the spheresspheres•All 4 spheres interact with each otherAll 4 spheres interact with each other

– Volcanoes (geo) erupts, sending ash and Volcanoes (geo) erupts, sending ash and gases into the air (atmos) and lava and gases into the air (atmos) and lava and ash down into surrounding forest (bio)ash down into surrounding forest (bio)

Interactions change the Interactions change the spheresspheres• Short change –Short change –

– A late freeze kills vegetable plantsA late freeze kills vegetable plants– A downpour cause roads to cave inA downpour cause roads to cave in

• Long term change – Erosion the continual Long term change – Erosion the continual breakdown and transportation of the solidbreakdown and transportation of the solid

• Humans can be affected by the interaction Humans can be affected by the interaction of the spheres and they can affect the of the spheres and they can affect the spheresspheres

– Burning of fossil fuels leads to more COBurning of fossil fuels leads to more CO22 in the atmospherein the atmosphere

Chapter 1.3Chapter 1.3

Cycles of EarthCycles of Earth

•A cycle is a sequence of events A cycle is a sequence of events that repeatsthat repeats

The Water CycleThe Water Cycle

•A continuous circulation of water A continuous circulation of water through the hydrosphere (p 13 through the hydrosphere (p 13 diagram)diagram)

•Some water evaporates quickly Some water evaporates quickly of breathed out (transpired) by of breathed out (transpired) by leaves of plantsleaves of plants

•Evapotranspiration – cycling of Evapotranspiration – cycling of water into the atmosphere by water into the atmosphere by evaporation and transpirationevaporation and transpiration

The Carbon CycleThe Carbon Cycle

•A biogeochemical cycle involving A biogeochemical cycle involving the element carbonthe element carbon

•Things that release carbon into Things that release carbon into the atmospherethe atmosphere– Breathing, decaying organic matter, Breathing, decaying organic matter,

burning of fossil fuels, forest fires, burning of fossil fuels, forest fires, volcanoesvolcanoes

•Things that remove carbonThings that remove carbon

•Caron Sink – where carbon is stored Caron Sink – where carbon is stored due to the death and burial of due to the death and burial of organisms with carbon in their organisms with carbon in their tissuestissues

•The ocean removes about 40% of the The ocean removes about 40% of the carbon in the atmospherecarbon in the atmosphere

The Energy CycleThe Energy Cycle

• Is the movement of energy into Is the movement of energy into and out of the earth systemand out of the earth system

•The amount of energy in should The amount of energy in should equal the amount out. If it doesn’t equal the amount out. If it doesn’t the climate would get warmer.the climate would get warmer.

•99.985% of the energy on earth’s 99.985% of the energy on earth’s surface comes from the sun as surface comes from the sun as solar energy. Drives; wind, solar energy. Drives; wind, currents and wavescurrents and waves

• .013 is energy from the earth geothermal .013 is energy from the earth geothermal energy. Powers; lithosphere – (plate energy. Powers; lithosphere – (plate movement) volcanoes, geysers earth movement) volcanoes, geysers earth quakes and the rock cyclequakes and the rock cycle

• .0002 is tidal energy due to the pull of .0002 is tidal energy due to the pull of the moon on the ocean’s waters.the moon on the ocean’s waters.

• To maintain the energy budget of the To maintain the energy budget of the incoming energy 40% reflected back to incoming energy 40% reflected back to space the rest is used in the earth space the rest is used in the earth system.system.

Law of ThermodynamicsLaw of Thermodynamics

•11stst Law Energy can not be created Law Energy can not be created or destroyed only changed form or destroyed only changed form one form to another.one form to another.

•22ndnd Law – when energy changes it is Law – when energy changes it is converted from a more useful, more converted from a more useful, more concentrated form to a less useful, concentrated form to a less useful, less concentrated form. Energy can less concentrated form. Energy can never be recycled (like water)never be recycled (like water)

The Effects of Earth’s The Effects of Earth’s SurfaceSurface•Due to the differences on earth’s Due to the differences on earth’s

surface (glaciers, water, light land surface (glaciers, water, light land and dark land) it will reflect solar and dark land) it will reflect solar energy differently.energy differently.

•Albedo – is the percent of energy Albedo – is the percent of energy that is reflected without being that is reflected without being changed.changed.

•Lighter colors have a higher albedo Lighter colors have a higher albedo (e.g. ice) than darker colors (e.g. (e.g. ice) than darker colors (e.g. forest) which have a low albedo.forest) which have a low albedo.

•An areas albedo can change – An areas albedo can change – green field vs. a plowed field, green field vs. a plowed field, summer green vs. winter whitesummer green vs. winter white

Human Activities and the Human Activities and the CyclesCycles•Human Activity can affect the Human Activity can affect the

interaction of the spheres and interaction of the spheres and cyclescycles– Burning fossil fuels adds more carbon Burning fossil fuels adds more carbon

to the atmosphereto the atmosphere

•All the actions of humans have an All the actions of humans have an effect on the earth. Earth Science effect on the earth. Earth Science System tries to figure out how far System tries to figure out how far and deep the effect travels.and deep the effect travels.