Introduction to Earth and Space Science

Earth and Space Science are split into several different sciences…Geology-study of the physical EarthOceanography-study of the Earth’s seasMeteorology- study of Earth’s atmosphereAstronomy- Study of the Universe

What is the Earth?

The Earth is… a large mass of solid, liquid, and gaseous matter…that revolves around the sun…rotates on an axis…and has one solid moon that revolves around it

What is the difference between rotation and revolution?

Rotation- turning around an axis

Revolution- moving around another object

Earths rotation affects us every day.-it gives us our 24 hour day-it causes us to alternate between night and day

Earth’s revolution also affects us.-Earths axis causes us to have seasons as it revolves around the sun.

Inside the Earth

What is the earth made of?

The earth is divided into three main layers, the crust, the mantle, and the core.

The Core - dense center of the earth made mostly of iron with small amounts of nickel. -it has two parts, the inner core (solid) and the outer core (liquid)-the movement of the metals inside the core create earth’s magnetic field

The Mantle-molten rock layer between the crust and the core-it has three parts, the mesophere (part extending down to the core), the

asthenosphere (part on which the pieces of the lithosphere slide), and the lithosphere (the rocky crust and mantle with which it interacts)

The Crust- thin, solid outer layer of earth above the mantle and below the atmosphere.

-There are two types of crust, continental (thicker but less dense part on which we live) and oceanic (thinner but denser between the continents)

What are tectonic plates?

The Lithosphere is broken into pieces called tectonic plates that float and move on the denser Mantle.

These plates include some oceanic crust, continental crust, and some of the mantle beneath them.

Earth’s Tectonic Plates

What is going on inside the earth?

• The particles of fluids (like most of the inside of the earth) can move freely.

• They move from warmer areas to cooler areas, from higher pressure areas to lower pressure areas.

• The hotter things become, the more particles spread out, the less dense they become and the better they float…

This means…

• That the liquid outer core flows in a current around the inner core.– When metals spin close to other metals,

electrons start to be pulled around and a magnetic field is produced.

• That the fluids in the mantle heat up and rise towards the surface. As they near the surface, they cool and sink back down. – These patterns of rising and falling are called

convection currents

• Moving fluids in the mantle push around and occasionally break through the tectonic plates.– This results in continental drift, earthquakes,

and volcanoes.

• The magnetic field produced by the spinning core protects us from radiation from the sun and helps maintain our atmosphere.

Climate, Weather, and the Atmosphere

One way to describe a place is to examine its climate. What is a climate?

Climate is similar to weather but more general and over a longer period.

Describing what it is like right now is describing the weather.Describing what it is usually like is describing the climate. Climate is the average weather conditions for a particular area.

The two things that make one climate different than another is the precipitation (amount and how it falls) and temperature (how hot, cold, and variable).

Precipitation- it could rain a small amount frequently, it could rain a large amount seasonally, or it could barely rain at all.

Temperature- it could be cold most of the year (polar), it could be hot most of the year (tropic), or it could change a lot being hot in the summer and cold in the winter (temperate).

Climate affects the type of plants that grow in a particular area and the type of soil.

Climate is decided by the amount of solar radiation (heat from the sun), the movement of the atmosphere, and the movement of the oceans.

-The oceans and atmosphere move because of temperature gradients caused by uneven solar radiation (different parts of the earth getting more heat from the sun) and the rotation of the earth. ***more detail on ocean and atmospheric currents will come later in the unit

How much sun a place gets is decided by its distance from the equator (latitude) and the revolution of the earth, on an axis, around the sun (causing seasons).

Elevation can also affect temperature.Atmospheric pressure decreases at higher elevations, so temperatures also decrease.

Large bodies of water also affect temperature.Water transfers heat slower than land does, so areas around large bodies of water have more moderate temperatures.

Because climate varies so much place to place, areas of earth are categorized into different biomes.

-Biome- a region of earth with a certain type of climate and certain types of plant communities.

Color Quiz

-The atmospheric conditions right now is an area’s ____________.Blue- weather Red- climate-Both precipitation and ____________ affect climate.Blue- plant communities Red- temperature-The revolution of the earth around the sun causes ____________Blue- seasons Red- day and night-As elevation increases, what happens to temperature?Blue- decreases Red- increases- The movement of the oceans can affect an area’s climate?Blue- false Red- true- An area’s ______________ also affects its climate.Blue- latitude Red-longitude-The main driving force of weather/climates on earth is _________________.Blue- ocean movement Red- solar radiation

How would you describe Massachusetts’ climate?

Biome Diversity- These are averages. Local information varies based on geography

Tropical:-Rainforests- 77-82°, 200+ cm precipitation. Heavily leached soil-Savannas- 80-90°, 100cm precipitation, usually poor dry soil-Deserts- 61-120°, 0-25cm precipitation, poor soil

Temperate:-Forests- 32-82°, 76-250 cm precipitation, very fertile soil-Grasslands- 21-78°, 38-76 cm precipitation, most fertile soil-Chaparrals (Mediterranean)- 51-78°, 48-56 cm precipitation, rocky, poor soil-Deserts- 34-120°, 0-25 cm precipitation, poor soil

Polar:-Taiga- 14- 59°, 40-61 cm precipitation, acidic soil (because of pine trees)-Tundra- -17-41°, 0-25 cm precipitation, frozen soil most of the year

What is a microclimate?

A microclimate is the climate for a small, specific area. The size can vary.

e.g. Western Oregon is kept warm by ocean currents and heavy cloud covere.g. Cities are usually a few degrees warmer than the surrounding areae.g. It can be a few degrees cooler in the shade of a blade of grass

The cells of all living organisms are filled mostly with water.It is also a key component in Photosynthesis and other organic processes.

Water is constantly moving, but how?

The water cycle is the continuous movement of water from the surface of the earth to the atmosphere and back,

Water on earth’s surface evaporates (turns into water vapor) and moves up into the atmosphere.

When it cools, it condenses (turns back into liquid water) and sticks to dust particles in the air, forming clouds.

When there is too much water in the air for the clouds to hold (saturation), precipitation (rain, snow, sleet, or hail) falls.

On the ground, water either percolates/infiltrates (seeps into the soil and becomes part of the groundwater) or it runs-off (flows in rivers and streams towards the ocean).

Any time that it is on the surface it has the potential to evaporate again.

Some water molecules can get stuck in the ocean or in glaciers for years, but they always eventually rejoin the water cycle.

All of the water on earth is linked, constantly flowing from one body to the next.

Rivers and streams (runoff) that run into the same body (an ocean, lake, or larger river) together form a river system.

The streams or rivers giving water to larger rivers or lakes are called tributaries.

All of the land contributing water to a particular river system is called a watershed.

Most of the water on earth is in the ocean, but individual water molecules are constantly moving.

Ocean Currents

Surface ocean currents are affected by several things, movement of the air, the Coriolis Effect, the position of continents, and temperature.

Liquids and gases tend to move from warm places (lots of energy and pressure) to cool places (less energy and pressure).

-As a result warm air and water from the equator tends to move towards the poles.

Since the earth is rotating, water trying to go north or south gets pushed to the side.

-This is the Coriolis Effect-In the Northern Hemisphere currents are pushed in a clockwise direction-In the Southern Hemisphere they are pushed in a counter-

clockwise direction

There are also deep ocean currents, but they depend more on temperature and how dense the water is (changes depending on how much salt is in the water).

Ocean Current’s effect on climate

Since water changes temperature much slower than air does, a prevailing wind that comes from over a warm ocean current will be warmer and bring that warm air to the land.

Places like the British Isles and the Pacific Northwest have milder climates because of this warming effect.

These same prevailing winds also send a lot of moisture onto land and cause these places to be frequently cloudy and rainy.

Lands alongside cold ocean currents are often dryer (Southern California)

Water temperatures do change periodically, which affects the ocean currents, and weather around the world (storms, drought, etc).

El Nino- a shift in the Pacific currentsEl Nina- a shift in the Atlantic currents

Atmospheric currents

Air moves from areas of high pressure to low pressure (wind).Pressure is highest at the surface of the earth where there is a lot of atmosphere above pushing down and lowest at high elevations.Pressure is also affected by temperature

-high temperature equals high pressure

Changes in temperature causes air to rise and fall, which brings it into areas of high or low pressure

Air rises, falls, moves from high pressure to low pressure and settles into predictable patterns or convection belts.

There is one belt between 0° and 30° latitude, one between 30°and 60°, and one between 60°and 90°.

Air is also affected by the Coriolis Effect, so it has the same left right movement as the ocean surface currents.

Winds coming from the west are called Prevailing WesterliesWinds coming from the east are called Trade Winds

Most of the world’s deserts are located around 30°N or S, because the cool falling air usually does not contain as much moisture as the air rising from the earth’s surface.

As a result of the ocean current in the Northern Atlantic, the ocean is usually warm.

However, because of the Coriolis effect, most of our weather comes from our west, so our air is not warmed as much by the water as the Pacific Northwest or British Isles.

Our latitude (approximately 42 degrees north) and air currents mean that we get enough precipitation to have healthy forests, but not enough to be rainforests.

-it also means that our days during the winter are shorter than during the summer, which gives us very different temperatures in the winter and summer.

Massachusetts’ climate

Atmospheric composition

The atmosphere is composed primarily of Nitrogen gas (78%).

Oxygen is the next most abundant at 21%.

All other gases, including water vapor and carbon dioxide, combine to make up a total of 1%.

Air is not “nothing”, it is full of matter. It is a mixture of gases that have mass and weight.

Atmospheric pressure is greatest at low elevations because all the mass and weight of high elevation gases push down on the lower gases.

The atmosphere is broken down into layers, each with a different composition and properties (troposphere, stratosphere, mesosphere, and thermosphere).

What things do living things do (biological processes) that affect the atmosphere?

What does the physical earth do (geological processes) that affects the atmosphere?

We constantly pull gases out of the air and put new ones into it.

Cellular respiration- oxygen in, carbon dioxide outPhotosynthesis- carbon dioxide in, oxygen outNitrogen fixation- nitrogen gas turned into usable moleculesDecomposition- some compounds into the ground, others back to the atmosphere

Fires- put carbon dioxide and other gases into the atmosphereVolcanoes- release carbon dioxide and sulfuric gases into the atmosphereEvaporation- liquids (mostly water) turn into gases and enter the atmosphere

How do people affect the atmosphere?

The biggest impact is on the carbon/oxygen ratio.-We burn fossil fuels, putting carbon dioxide and other greenhouse

gases into the air.-We cut down forests, which are responsible for taking out carbon

dioxide and putting in oxygen.

We also release CFCs (chlorofluorocarbons) which bloke the ozone layer’s (upper layer of the stratosphere) ability to absorb dangerous forms of solar radiation.

Why do we need an atmosphere?

The oxygen that almost all living things need for cellular respiration comes from the atmosphere.The carbon dioxide that plants use for photosynthesis comes from the atmosphere.All of the proteins in the bodies’ of every living thing are made of nitrogen atoms that at one time were in the atmosphere.

Animals, like insects and arachnids, that don’t actively suck in oxygen can’t grow very big. However, when oxygen concentrations in the atmosphere are higher, they can evolve larger bodies.

Another reason we need the atmosphere is global warming.

The atmosphere acts like a blanket, keeping some of the heat we receive from the sun here, instead of letting it bounce out into space.

Too thin an atmosphere and temperatures become extreme, too hot during the day and too cold at night.

Too thick an atmosphere and earth retains too much heat.

The moon doesn’t has an atmosphere:-233°C at night, 123°during the dayVenus has a thick atmosphere: 460°C all dayEarth has a moderate atmosphere:10°C at night, 20°C during the day

Increasing the amounts of greenhouse gases in the atmosphere (e.g. carbon dioxide and water vapor) makes our atmosphere thicker.

So what is weather?

Weather is atmospheric conditions right now.

It is a result of the temperature, atmospheric pressure, moisture, and movement of the atmosphere over a given area.

These things are ultimately controlled by the same things as climate, the movement of the earth, radiation from the sun, and the earth’s physical and chemical features. When they change weather changes.