AP Environmental ScienceEarth Systems

In the beginning….•Our Universe began as a very

hot, very dense cloud of high energy hydrogen plasma

• The “Big Bang” is the finite point, 13.7 BYA when for some reason the universe started to expand in all directions

•The universe has expanded and cooled ever since this point

• In the first microseconds after the big bang, elementary particles (quarks and leptons) dominated the universe independently

•As the universe cooled, layer upon layer of structure began to form, first neutrons and protons atomic nuclei atoms stars galaxies galaxy clusters

•Our universe is now populated by an estimated 100 billion galaxies, each with 100 billion stars each of those having planets orbiting

How do we know, why do we think..

•1) We know that the universe is expanding▫By looking at the color of distance stars we

can tell whether they are approaching or receeding

▫If the color of the star appears blue (blueshift) then the star is approaching earth, shortening the wavelengths of light turning it blue

• If the color appears red(redshift) then the distance between us and the star is increasing stretching the wavelengths of light shifting them toward the longer red wavelengths

• The further the distance between us and the star the greater the redshift because they are travelling at higher speeds (Edwin Hubble,1929)

• This is known as a Doppler wobble or Doppler shift

http://diagrammar.wordpress.com/

•2)Helium and Deuterium is universally abundant, and predates the formation of stars. ▫The only things today beside nuclear bombs

that can create these elements are stars•3) Cosmic Background Radiation▫When looking at the sky with a radio telescope,

there is a universal “glow” of microwaves the blankets the universe.

▫The uniformity indicates one original source of the radiation, the big bang

http://www.ugcs.caltech.edu/~yukimoon/BigBang/BigBang.htm

Temperature variations of the cosmic background radiation as measured by WMAP ( difference between colors is 0.0002 Kelvin, average temperature 2.75 Kelvin)

http://faculty.washington.edu/

Home Sweet Home in the Milky Way

•The Milky Way is a barred spiral galaxy•100,000 light years in diameter•1000 light years in thickness•100 -400 billion stars•Oldest star is 13.2 BYO•We are located 26,000 light years from the

galactic center•We are spiraling at roughly 552km/s

Infrared image of the center of the Milky Way Galaxy taken by the Spitzer Space Telescope

Photograph of the night sky highlighting our galaxy as the hazy band of stars across the sky

Our location on one of the spiral arms

Howdy Neighbor..•The Andromeda Galaxy is our

nearest relative • It contains roughly 100 trillion stars•Located 2,500,000 light-years away •220,000 light-years in diameter• It is approaching us at roughly 140

km/s and we will collide in about 2.5 billion years to possibly form one giant galaxy

Infrared Image of Andromeda Galaxy taken by the Spitzer Space Telescope

©John Lanoue

Twinkle, Twinkly little star…•Space is thinly filled with gas (H2 & He) and

dust ( carbon & silicon) called interstellar medium

• In some places the gas and dust collect into large clouds called nebula- the birthplace of stars

•The nebula contains pockets of higher gravity that cause the matter to clump together, the clumps get bigger and bigger in a process called accretion

•The continued process of accretion will eventually form a protostar

•The functional life of a star is complicated balancing act between the gravity pulling atoms inward and the physical forces pushing heat and light away from the center

•When equilibrium is first reached the star ignites- ▫if because of temperatures it fails to ignite it

becomes known as a brown dwarf▫If it does ignite, nuclear fusion begins to happen

and the star is born

Eagle Nebula-Pillars of Creation Star Forming Region of Doradu Nebula

Turbulent Gases in the Omega/ Swan Nebula

The Orion Nebula

http://hubblesite.org

•A star spend the majority of its life in what is known as the main sequence- where it constantly fuses hydrogen into helium

•Stars constantly contract during their life, about 50 million years for a medium size star, increasing the temperature and pressure inside the star to compensate for the loss of heat and energy

The Death of a Star•Once the hydrogen fuel source in the core

is gone it will start burning helium. •The outer shell will burn the last bits of

hydrogen causing the outer shell to expand aiding in the release of heat from the core creating a red giant

•

Supernova of a star first seen in 1987 by the Hubble Telescope

•The expanding gases will then be cast off producing one of the following▫Small stars- white dwarf ( size of Earth) and

a planetary nebular▫Medium stars – supernova producing a

neutron star( size of a city)▫Large stars – form black holes

• It is the death of stars that is responsible for the creation of the heavier elements

White Dwarf in the center of a planetary nebula, the result of the death of a smaller star, like ours

http://sunshine.chpc.utah.edu/

The Crab Nebula is a pulsar wind nebula associated with a 1054 BCE supernova

Another Trip Around the Sun•From the nebula come not only stars but

also protoplanetary disks of gas and dust•Our solar system might have formed from

the disruption caused by a nearby supernova

•Accretion in this disks once again causes the dust to pile up and it will start to rotate around the solar center, the center become the star and the outer bands form planets

•The gravity of the disk pulls heavier materials toward the center giving way to rocky planets such as Earth, Venus and Mars

•Lighter icy materials remained in the outer reaches of the spiral forming the giant planets like Jupiter

•From studying meteorites it is believed that our solar system is 4.6 billion years old

http://www.windows.ucar.edu

A diagram of our solar system

http://www.diagramofsolarsystem.com/

•Our Sun▫Age- 4.5 billion years old▫Distance from Earth-150,000,000 km▫Diameter-109x the size of Earth▫ ( 1,390,000 km)▫Mass- 333,000x the mass of Earth▫Composition -73 % hydrogen, 25% helium, 2%

other ( carbon, iron, neon, nitrogen, silicon, magnesium, sulfur)

The Inner Planets•Terrestrial Planets•Dense rocky compositions•Few or no moons, no ring systems•Silicate minerals form their crust• Iron and nickel cores•3 of 4 have atmospheres ( Venus, Earth,

Mars) and weather patterns•Mercury’s was blown off by stellar winds

Size comparison of the inner planets ( NASA)

Asteroid Belt•Asteroid- small solar system bodies that

orbit the sun•Located between the planets Mars and

Jupiter•From a few feet to hundreds of miles wide▫It contains over 40,000 rocks over ½ mile

across

The asteroid belt between Mars and Jupiter

The Outer Planets•Gas Giants• Jupiter and Saturn consist of a large

amount of hydrogen and helium•Uranus and Neptune possess a greater

proportion of ices ( frozen water, ammonia, methane)

•All of the gas giants have ring systems but only Saturn’s is observable from earth

The outer Jovian Planets

BBC-Jupiter Explosion Video

The orbits of the solar system

Earth-Sun, Like peas in a pod•The Earth’s orbit around the sun is called a

revolution, this revolution takes 365.26 days

•Hence every four years we have a leap year to catch up

•The orbit is elliptical, causing our distance from the sun to vary, and our energy from the sun fluctuates by about 6%

Round and Round we go..•On January 3rd the Earth is closest to the

sun(147.3 million Km), this is called the perihelion

•On July 4th the Earth is the farthest from the sun(152.1 million Km), this is called the aphelion

•The average distance from the sun is 149.6 million Km

Earth’s Orbit

•There are two major events in the Earth’s orbits- the solstice and the equinox

•The solstices occur in the winter (Dec 21/22) and in the summer (June 21/22)

•The equinoxes occur in the spring (Vernal, March 20/21) and the fall (Autumnal, Sept. 22/23)

•During the equinoxes there are 12 hours of day/12 hours of night

•The summer solstice is the longest day of the year

You spin me right round…•The Earth rotates on an axis, and

imaginary line that runs through the poles of the Earth

•Earth’s axis is not completely vertical, it is tilted 23.5o from perpendicular

• It is the relationship between Earth’s tilt and its orbital revolution that creates the seasons

http://www.physicalgeography.net/fundamentals/6h.html

Earth’s Orbit and the seasons

Summer Solstice Winter Solstice

Vernal and Autumnal Equinox

How the tilt of the Earth affects which hemisphere is facing the sun

•Earth is actually closest to the sun in the winter time, and furthest away in the summer

•When it is summer in the northern hemisphere then it is winter in the southern hemisphere

Round and Round..•The Earth rotates east to

west, or counter-clockwise (when viewed from the North Pole)

•The rotation of the Earth takes approx. 24 hours

•Seasonal effects on the Earth▫Changes in solar altitude▫Changes in day length▫Changes in apparent solar intensity ▫Changes in temperature

•Changes in the seasons are the most extreme at the poles and minimized at the equator

Light from the sun•Solar Radiation is received in parallel rays of

energy• Insolation- the measurement of solar energy

received on a given surface( Earth)•Commonly expressed as the average

irradiance, W/ m2 or kWh/(m2*day)• Intensity of incoming solar radiation

(insolation) is related to angle of incidence. Higher angles = higher intensity

•The sun irradiates 63,000,000 W/ m2 •Depending on distance and size of an

object, we can calculate the amount of energy that we receive

A 1 mi sunbeam striking the Earth at 90o disperses it energy over 1mi of surface, while a sunbeam striking at 30o spreads the energy over a surface area of 2 miles

•At the top of the atmosphere- 1,366 W/ m2 of energy is received (2 billionths )

•Atmospheric phenomena such as clouds and weather patterns affect the amount of solar energy that reaches the surface

•Geographic location, time of day and landscape can also affect the amount of energy received

•Perpendicular locations receive roughly 1000 W/ m2 on a clear day

•Earth’s average insolation is 250 W/ m2

http://www.eoearth.org/article/Solar_radiation

Average solar radiation received in the Us

Earth’s energy budget•30% of the sun’s energy is reflected by the

atmosphere and the surface•19 % is absorbed by the clouds and

atmosphere itself, an reradiated back into space

•51% of the energy is absorbed by the landscape and oceans to warm it

•70% of the total energy we receive is reradiated back into space

•0.023 % of that energy is used for Photosynthesis to fuel the food chain

http://www.geology.wisc.edu/homepages/g100s2/public_html/Geologic_Time

Time after time•The geologic time scale is broken up into

several pieces▫Eons ( 4 total, ½ billion years or more)▫Era (12 total, several hundred million years)▫Periods (defines periods of life)▫Epochs( tens of million years)▫Age ( millions of years)

Time after time..•Hadean Eon 4.6-4.0 BYA▫Formation of the Earth’s crust and

bombardment by comets and asteroids•Archean Eon 4.0-2.5 BYA▫First life appears, plate tectonics

established, oxygen poor atmosphere•Proterozoic Eon 2.5 BYA – 542MYA▫First multicellular animals toward the end, 4

major mountain building episodes (orogeny) [ Grenville & Pan-African] and the oldest known and most severe glaciation event

•Phanerozoic Eon 542 MYA-present•Paleozoic Era 542-252MYA▫Cambrian Period- Began with the Cambrian

explosion, first skeletonized animals▫Ordovician Period- ended with a mass

extinction▫Silurian Period-estuarine, freshwater and

terrestrial ecosystems developm, major terrestrial life

▫Devonian Period- age of fishes, first land vertebrates, diversification of the vascular plants

▫Mississippian Period-first terrestrial tetrapods

▫Pennsylvanian Period-”coal age”-major plant fossils that make up the major coal seams

▫Permian Period- the end of this era is marked by the most extensive mass extinction in the past 600 million years rise of dinosaurs and modern critters, lots of insects, major dominance of coniferous plants

•Mesozoic Era 252-65.5 MYA▫Triassic Period –recovery from previous

mass extinction, rise of the dinosaurs, early mammals, first coral reefs

▫Jurassic Period – “Age of the Dinosaurs”, first birds(aves), first parasites

▫Cretaceous Period- extinction of the dinosaurs, birth of the angiosperms

•Cenozoic Era 65.5MYA – present•Paleogene Period▫Paleocene Epoch – “Age of Mammals”

begins, seeded vascular plants dominant▫Eocene Epoch –maximum extent or warm

and tropical vegetation, evolution of marine mammals

▫Oligocene Epoch- appearance of most of the still living mammal families

•Neogene Period▫Miocene Epoch – most of the extant

marine invertebrates exist, major ocean circulations form, seasonal climates dominate the north hemisphere

▫Pleistocene Epoch- human geographic expansion and cultural development, first major human-influenced extinctions

▫Halocene Epoch- present day- climate warming following the last ice age, continents drying out, polar regions contract, plant communities change with climate

http://paleobiology.si.edu/geotime/main/

Welcome to Earth, third rock from the sun..

•Earth is the fifth largest planet and the largest terrestrial planet

•The shape of the Earth is an oblate spheroid-”squished ball”

•The diameter across the equator is 43 km larger than the pole to pole diameter▫Diameter is roughly 12,742km

•Mass = 5.98 x1024 kg

Tidal forces that cause the planet to be an oblate spheroid

•Chemical composition-▫32.1 % Iron▫30.1 % Oxygen▫15.1 % Silicon▫13.9 % Magnesium▫2.9 % Sulfur▫1.8 % Nickel▫1.5% Calcium▫1.4% Aluminum▫1.2% Other trace elements

•The Earth has several layers▫The Crust- the hard outer shell

Thin and floating on molten mantle (Lithosphere) Two main types Oceanic (6-11km) and

Continental (30 km) Broken up into several large plates called

tectonic plates▫The Mantle

Begins between 10-30km below the crust 2,900km thick, 80% of the Earth’s Volume Divided into the inner and outer mantle

Outer mantle (10-300km) 1,400 - 3,000oC Molten rock, part closest to crust is thicker and

slower moving, plastic-like consistency (Asthenosphere)

Inner mantle (300-2,890km), 3000oC • The Core

•Found 2,900km below the surface•Dense ball of iron and nickel•Two layers•Outer core-molten metal, 2,200km thick

-Rotates around the inner core and creates Earth’s Magnetic field

•Inner core- solid due to pressures, even though its 3,700oC , 1,250km thick

http://mediatheek.thinkquest.nl/~ll125/en/struct.htm

http://www.seismo.unr.edu/ftp/pub/louie/class/100/interior.html

•The Earth is also divided up into four spheres▫Biosphere, Lithosphere, Hydrosphere and

the Atmosphere

•Lithosphere-”rocky sphere” the outermost portion that provides a platform for life, contains the crust and the uppermost portion of the mantle▫The asthenosphere is located just

underneath- moves the tectonic plates•Hydrosphere-”water sphere” the liquid

realm of the Earth, principally the mass of water in the worlds oceans▫70% of the surface is covered with water▫366.3 trillion gallons

•Biosphere-” Life sphere” Most of the biosphere is contained within a thin layer of the planet called the life layer▫Overlaps with all of the other spheres ▫2200-4000 Gigatons of Biomass (2.2-4

Trillion tons)•Atmosphere-” Air sphere” The gaseous

layer that surrounds the Earth. It supplies some of the basic features that support and sustain life on this planet▫4 Major layers, 99% is Nitrogen and Oxygen

http://ga.water.usgs.gov/edu/mearth.html

Mapping our planet..•The Equator divides the world into

Northern and Southern Hemispheres•Latitude-angular measurement of the

distance north or south of the Equator▫Range: 0-90o N or S▫1o is roughly 69 miles on the surface

•Parallels of Latitude - Imaginary lines that connect points of equal latitude, thus slicing the earth into equal “layers” like on a wedding cake

Important Parallels

•The Prime Meridian divides the world into eastern and western hemispheres

•Longitude the angular measurement of distance east or west of the Prime Meridian or Greenwich Meridian.▫Range: 0-180o E or W

Geographic Grid•The combination of longitude and latitude

that makes every point on this Earth easily identifiable and locatable

World Address of Major CitiesBerlin, Germany

Beijing, China

Paris, France

Moscow, Russia

London, England

Rio de Janeiro, Brazil

World Address of Major CitiesBerlin, Germany -52.9oN 12.5oEBeijing, China – 39.95oN 116.5oEParis, France – 48.8oN 2.25oEMoscow, Russia – 55.8oN 37.6oELondon, England – 51.5oN 0.1oWRio de Janeiro, Brazil - 22.95oS 43.2oW

Map Projections•Mapping the surface of the Earth is

difficult because it is round and maps are typically flat

•3 major types of map projections are used▫Conic▫Cylindrical/Mercator ▫Azimuthal

•Conic Projections▫Good for northern/ southern locations

distorts near the edges-equator•Mercator Projections▫Good for equatorial locations but distorts

near the poles•Azimuthal /Planar ▫Limited scope or area covered, but

preserved the ideas of direction on the map

River Deep, Mountain High•Geomorphology-the scientific study of

landforms and the processes that shape them

Water, water everywhere..•Oceans▫Arctic Ocean

Smallest and most shallow, Partially covered in sea ice, temp and salinity vary, least salty of all oceans

▫Atlantic Ocean Second largest, 25% of water area, currently

growing, Divided into north and south Atlantic by equator

▫Indian Ocean Third largest, 20% of water area, begins at

the 20oE meridian

▫Pacific Ocean Divided up into the north and south pacific Largest ocean, and deepest ocean Currently shrinking

▫Southern/ Antarctic Ocean Fourth largest ocean, completely surrounds

Antarctica

•Sea of Okhotsk•Sea of Japan•Hudson Bay•East China•Andaman•Black Sea•Red Sea

•South China Sea•Caribbean Sea•Mediterranean Sea•Bering Sea•Gulf of Mexico•Arabian sea

Major Seas

http://www.worldatlas.com/aatlas/newart/locator/majorsea.htm

Major Mountain Ranges•Himalayas▫Highest mountain range, “land of snow”,

located in southern Asia, between India and southern Asia, one of the youngest mtn ranges- Mt Everest- 29,029ft tall

•Alps▫Located in south central Europe, one of the

largest and highest mtn ranges, 750 miles long- Mont Blanc 15.771 ft

•Andes▫Located in South America, runs north to south

along western edge of continent•Rockies▫Vast system in western North America,

stretches from Canada to New Mexico, about 3000 miles long-Mount Elbert-14,440 ft

Mtn Ranges by Continent (don’t copy)

• Antarctica: ▫ Antarctic Peninsula,

Transantarctic Mountains▫ The highest mountain,

Vinson Massif in the Ellsworth Mountains, peaks at 4897 m.

• Africa: ▫ Atlas, Eastern African

Highlands, Ethiopian Highlands

• Asia: ▫ Hindu Kush, Himalayas,

Taurus, Elburz, Japanese Mountains

• Australia: ▫ MacDonnell Mountains

• Europe: ▫ Pyrenees, Alps,

Carpathians, Apennines, Urals, Balkan Mountains

• North America:▫ Appalachians, Sierra

Nevada, Rocky Mountains, Laurentides

• South America: ▫ Andes, Brazilian

Highlands

Appalachian Mountains

Rocky Mountains

The Alps

Himalayan Mountains

Mt. Everest 29,029 ft / 8,848 m

Major River Systems•North American▫St Lawrence-2350 mi long, follows a fault line

and drains the Great Lakes▫Rio Grande▫Colorado- 1450 miles long, cut the largest canyon

system in the world including the Grand Canyon▫Hudson- 315 mi long, serves New York and can

be navigated beyond the mtns▫Mississippi River – 3,870 miles long, 1.25 million

mi2 drainage, longest river flowing southward, 25 major cities located on it banks

•North Carolina

North Carolina River Basins

•South America▫Amazon – 3,920 miles long, 2.3 mi2

drainage, largest basin in the world, greatest flow (180,000 m3)

•African▫Nile- 4,180 mi long, 1.7 million mi2

drainage, White and Blue Nile tributaries, Egyptians Agricultural is dependent upon seasonal flooding, flows north

▫Congo – 2900 mi long, 1.4 mil mi2 drainage, longest river flowing westward, crosses the equator twice

▫Zambezi – 2,200 mi long, 548,000 mi2 drainage, flows over Victoria falls

•Asian▫Tiger & Euphrates -1795 mi long, home

of ancient Mesopotamia, serves major Iraqi cities

▫Yangtze (Chang Jiang) – 3964 mi long,698,000 mi2 drainage, the lifeline of China

▫Yellow (Huang He) -3,395 miles long, 290,000 mi2 drainage, some of the river is higher than the surrounding area

▫Ganges- 1560 mi long, sacred river of India

•European▫Danube – 1,176 mi long, 320,000 mi2

drainage▫Rhine- 820 mi long, commercially the most

important river of Europe

Structure of a Watershed System- Hydrology

• Inside the geographic divide, all of the water in an area will eventually flow into one river channel

•The very small streams that first collect water at the source of the river are called headwaters

•Headwater tributaries are ranked by size, 1st order are the smallest, when they combine they form 2nd order streams, that will eventually come together and form 3rd order streams, so on and so on…

• Rivers channels are typically made up of a stream bed, with banks on either side, outside of the river banks are called flood plains

• The edge of the floodplain where the land and the stream meet is called a riparian zone or area

• It is usually lined with riparian vegetation, characterized by hydrophilic plants.

• These areas are important because they help prevent erosion, aiding in soil conservation. This is because they buffer the effects of fast moving flood waters

Braided River, multiple channels, New ZealandMeanders of the Rio Cuato

Formation of an Oxbow Lake

•Where the water pours out of a river channel into a larger body of water is called a delta

•The delta is where all of the sediment that is suspended in a stream dumps out, as the water slows

Mississippi River Delta

Migration of the Mississippi river channel and Delta

Amazon River Delta

Types of Rivers▫Youthful Rivers

A river with steep gradient, few tributaries and a rapid flow, the channel is usually deep and narrow

▫Mature Rivers Less steep gradient, flows more slowly. Many

tributaries and higher discharge. Channel becomes wider with time

▫Old Rivers River with a low gradient and very little

erosion, usually have extensive flood plains▫Rejuvenated Rivers

A river that has be lifted by tectonic uplift

Plate Tectonics•Theory was developed to explain large

scale motions of Earth’s lithosphere•Developed by Alfred Wegener•Very important because it maintains the

balance of carbon in the environment•Earth’s crust is broken up into several

major plates(7-8) and various secondary plates

•Continental Drift + Sea Floor Spreading + data = Theory of Plate Tectonics

Tectonic Plate boundaries marked by volcanic and seismic activity

Evidence for Plate Tectonics•Puzzle like fit of the continents•Fossil Distribution, Geologic similarities on

opposing shores•Sea-Floor Polarity patterns•Age of sea floor

Similarities of Geological Formation

•The lithospheric plates ride around on the asthenosphere- plastic-like layer of the upper mantle

•Plates interact with one another at 1 of 3 types of plate boundaries ▫Convergent –collision boundaries where

plates move toward each other▫Divergent –where the plates are moving

away from one another▫Transform boundaries- where plates slide

past each other, side to side

Plate Boundaries•Convergent Boundaries▫Ocean-Ocean

one plate(typically the older one) will subduct under the other volcanic island arc

▫Ocean-Continental The oceanic plate will subduct under the

continental plate melt volcanic arc & trench

▫Continental-Continental Neither plate will subduct plates begin to

fold and crumble mountain ranges

Mariana Trench – deepest part of the world’s oceans

2550 km long, 70 km wide

Challenger Deep11,033 meters deep (36,000 ft)

If Mt. Everest was set in the bottom it would be covered by 6000 ft of water