Physical Geography FINAL EXAM
Latitude - East/West lines that determine North/South locations.
Each parallel to the next
Sometimes called parallels
Expressed in degrees
90 degrees is the maximum amount of latitude
Longitude - North/South lines that determine East/West locations
Are not parallels; converge at the poles
Sometimes called meridians
Expressed in degrees
Greenwich Meridian Prime Meridian
0 degrees longitude
Line from which lines of longitude are numbered
Whenever you write coordinates, by convention, latitude MUST COME FIRST!
Latitude FIRST, Longitude SECOND
Tropic of Cancer
23.5 Degrees North
The northern most point on earth that experiences the direct rays of the sun
Tropic of Capricorn
23.5 Degrees South
The southern most point on earth that experiences the direct rays of the sun
Arctic Circle
66.5 Degrees North
The farthest point from the North Pole, in the northern hemisphere, that experiences at least one day when the sun does not rise and at least one day when the sun does not set.
Antarctic Circle
66.5 Degrees South
The farthest point from the South Pole, in the southern hemisphere, that experiences at least one day when the sun does not rise and at least one day when the sun does not set.
9/8/23
International Dateline - Line marking the point where each day ends and begins
24 time zones
Maps - Primary tool of the geographer
A map is a scaled representation of all 4 portions of the earths surface.
All maps in geography are reductions
CHECK PHONE PHOTOS FROM 9/8/23 FOR PICTURE OF EXAMPLE OF THE GRAPH THING
3 Methods of Scale Representation - Three ways that the cartographer can present map scale to us
Graphic Scale
Stated Scale - 1 inch = 1 mile
Representative Fraction (RF) - 1 : 24,000 (1 unit on the map is 24,000 of that same unit in real life)
All three shown in legend
9/11/23
U.S.G.S - United States Geological Survey
IN charge of overseeing any geological issue in the country, even the world. Floods, earthquakes, tidalwaves, etc...
Our Country's Mapping Agency
Small Scale Maps
Show a lot of area - little detail
EX: World Map
R.F. = 1:24,000,000
Large Scale Maps
Little area - lot of detail
R.F. = 1:24,000
3 Basic Types of Maps
Planimetric
Thematic
Topographic
Planimetric
Show two dimensional information only (2D)
No reference to altitude (Not needed)
EX: Road Map
Thematic (Topical) Maps
Present a theme or topic
Maybe of greatest use in presenting geographic information
Topographic Maps
Show Three Dimensional Information (3D)
Altitude Values are shown
Topographic from Topography
Topography - The surface features of the earth and their arrangement.
Ways to show 3D information
Raised Relief
Colors
Contour Lines
Raised Relief
Colors
Contour Lines - (Isolines) Connects points of equal altitude
9/13/23
Map Projections
The way that the surface features of the Earth are projected onto the map surface.
Great Circle
A great circle is any line which bisects the Earth into two equal half spheres
Significance - Any portion of a great circle represents the shortest distance between two points on Earth.
Great Circle Routes
9/15/23
The Universe - All Things
Cosmology - The study of the Universe
Astronomy - The study of space
Speed of Light - 186,000 Miles Per Second
The Light Year - The distance that light will travel in one year's time.
6,000,000,000,000 Miles
The Light Year is a measure of DISTANCE, NOT a measure of TIME!
How old is the Universe?
The Big Bang - Occurred between 13.6 - 14.0 billion years ago
How big is our universe?
The distance to the edge of the known universe is estimated to be about 14 billion light years
Galaxies - An organized group of stars.
Andromeda Galaxy
Barred Spiral
Hubble Deep Field Photo
Ring Nebula
9/18/23
Formation of Planets
Proto Earth
Terrestrial Planets
Relatively small size, rocky composition, dense, few moons
Mercury, Venus, Earth, Mars
Jovian Planets
Large in size, gaseous composition, not dense, many moons, ring systems
Jupiter, Saturn, Uranus, Neptune
The Solar System
Asteroids
Pieces of space rocks
Asteroid Belt
Comets
Meteors
Geography 9/20
Asteroids
Asteroid Belt
Comets
Comet Hale-Bopp
Comet 67P
Meteor
Meteors that survive the burn and reach the ground are called Meteorites.
Meteor Showers
Geography 9/22/23
Earth
Diameters of the Earth
Equatorial Diameter - 7,926 Miles
Polar Diameter - 7,900 Miles
26 Mile Difference
Polar Flattening
Relief
The difference in altitude between the highest and lowest points of an area or region
Relief of the world
Highest Point - Mount Everest: 5.5 Miles High
Lowest Point - Marianas Trench: 7.0 Miles Deep
Total Relief of the World - 12.5 Miles
Relief of Maryland
Lowest Point - Ocean City, MD: Sea Level: 0 Feet
Highest Point - Backbone Mountain: 3,360 Feet
Total Relief of Maryland - 3,360 Feet
Types of Terrain
Low Relief - Ex. Maryland's Eastern Shore
High Relief - Ex. Mountains in Western Maryland
High Rugged Relief - Ex. Rocky Mountains
Geography 9/25/23
Rotation
The spinning of the Earth around it's axis.
Axis - Imaginary line passing through the center of the Earth and intersecting the surface at the poles.
Period and Speed of Rotation
Period - 24 Hours (1 Day)
Speed - Varies with Latitude
Fastest at equator - 1040 MPH
Speed decreases with increasing latitude
At the poles - 0 MPH
Revolution
The movement of the Earth in its orbit around the Sun.
The Earth describes an elliptical orbit around the Sun.
93,000,000 Miles = 1 A.U. (Astronomical Unit)
Period and Speed of Revolution
Period - 365.25 Days (1 Year)
Speed - Varies depending on position in orbit.
Slower at Aphelion
Faster at Perihelion
Average speed - 67,000 MPH
The Seasons
The seasons are caused by a combination of the Earth's revolution and its inclination (tilt) to the ecliptic.
The Seasons
Vernal Equinox - First Day of Spring - March 21
Summer Solstice - First Day of Summer - June 21
Autumnal Equinox - First Day of Fall - Sept 21
Winter Solstice - First Day of Winter - Dec 21
The Seasons
The seasons are caused by a combination of the Earth's revolution and its inclination (tilt) to the ecliptic.
Geography 9/27/23
The Seasons
The Seasons are caused by a combination of the Earth's revolution and its inclination (tilt) to the ecliptic
Constellation
An arbitrary grouping of stars that today serve as reference points in the night sky
Geography 10/2/23
The Sun
Sun's Energy
Produced by Nuclear Fusion
4 Hydrogen atoms fused to form one Helium atom
The Sun is estimated to be converting Hydrogen to Helium at 400,000,000 tons per second
Electromagnetic Spectrum
Composition of Sun's Energy
51% Infrared or Longer Wavelength
41% Visible Light
8% Ultraviolet or Shorter Wavelength
Distribution of Insolation
30% - Wasted (Not Used)
20% - By Clouds
6% - By Particulates (Dust)
4% - By Surface
Insolation
In - Incoming
Sol - Solar
Ation - Radiation
Distribution of Insolation
Distribution of Insolation (Continued)
70% - Absorbed (Used by Earth System)
19% - By Clouds
51% - By Surface
Albedo
The amount of reflectance of an object or substance
Earth's Albedo = 30%
Geography 10/4/23
Primary Gases (Nonvariable Gases)
Nitrogen (N2) - 78%
Oxygen (O2) - 21%
Argon (Ar) - 1%
Important Long Term Variable Gases
- Carbon Dioxide (CO2) (Triatomic)
Important Greenhouse Gas
Essential component in the Carbon Cycle
Needed by plants
- Ozone (O3) (Triatomic)
An irritant and pollutant at the surface
Blocks UV radiation aloft
Trace Gases
- Examples:
Helium
Radon
Sulfur Dioxide
Carbon Monoxide
Methane
Thousands of others
Short Term Variable Constituents
Water Vapor (H2O)
Important Greenhouse Gas
Essential to the Hydrologic (Water) Cycle
Particulates (Dust)
Essential to the Hydrologic (Water) Cycle
Cooling effect on Atmospheric Temperatures
Geography 10/6/23
Troposphere
Temps go down with altitude
Tropopause - Upper boundary of the Troposphere
Troposphere is 5-11 miles thick
Stratosphere
Temps go up with altitude
Protective layer of ozone concentrated here
Stratopause - The upper boundary of the Stratosphere
Stratopause located at 30 miles above the surface.
Mesosphere
Temps go down with altitude
Mesopause - Upper boundary of mesosphere
Mesopause located 50 miles above surface
Zone of meteor disintegration
Thermosphere
Temps go up with altitude
No distinct upper boundary
Zone of the aurora
Aurora Borealis - Northern hemisphere Aurora Australis - Southern hemisphere
Geography 10/9/23
Weather
The condition of the atmosphere with respect to the weather elements for a SHORT period of time
Climate
The range of weather possibilities and probabilities for LONG periods of time
The Weather Elements
Temperature
Air Pressure
Wind
Moisture
Air Masses
Storms
Atmospheric Temperatures:
The Atmosphere is warmed by the surfaces of the Earth utilizing Sun's energy
Earth's surface absorbs Sun's energy... and converts it to heat energy... and radiates it out to atmosphere
Some heat energy is lost to space... most is trapped in the atmosphere by the "Greenhouse Effect"
The Greenhouse Effect
The heat trapping ability of the Earth's atmosphere
Primary Greenhouse Gases
Carbon Dioxide - CO2
Water Vapor - H2O
Methane - CH4
Geography 10/11/23
Average Noon Sun Angle *** (VERY IMPORTANT)
Latitude - Generally speaking temps decrease with increasing latitude.
Season - Lower sun angles in winter; higher sun angles in summer (When sun is higher up, its more concentrated on one area; when sun is lower, its more spread out)
Land/Water Distribution
Northern Hemisphere - 52% Water (Ocean), 48% Land
Southern Hemisphere - 88% Water (Ocean), 12% Land
Temperatures more evenly distributed in Southern Hemisphere
Isothermal Map
Isotherm - Another example of an Isoline (Lines which connect points of equal value)
An Isotherm is a line that connects points of equal TEMPERATURE
Ocean Currents
Warm Currents - Flow along East coasts of continents
Cold Currents - Flow along West coasts of continents
East Coasts tend to be warmer
West Coast weather generally more stable
Gyres - A large system of rotating ocean currents.
Global Heat Balance - The global heat balance is the balance between incoming and outgoing heat on Earth. (Ocean currents mix warmer water with cooler water to balance the temperatures)
Altitude
Normal Lapse Rate - Average rate at which temperature goes down with altitude. Temperatures decrease 3.5 Degrees F/1,000 Feet
High mountainous areas are colder
Factors Affecting Temperature Distribution (RECAP)
Average Noon Sun Angle (MOST IMPORTANT)
Land/Water distribution
Ocean Currents
Altitude
Geography 10/16/23
Wind Chill - The subjective amount of cold brought about by the combination of temperature and wind speed. (Wind makes it feel colder)
Wind Chill Index
Heat Index - The subjective amount of heat brought about by the combination of temperature and humidity. (The humidity makes it feel hotter)
Blank area is where dewpoint > 85F
Radiation - Heat transfer without contact Conduction - Heat transfer with contact Convection - Heat transfer through movement
Urban Heat Island - When cities replace natural land cover with dense concentrations of pavement, buildings, and other surfaces that absorb and retain heat.
Annual Temperature Range - The difference between the hottest and the coldest months by taking monthly mean temperatures in each case.
Changes seasonally
Highest annual temperature ranges are found in the high altitudes. Lowest annual temperature ranges are found in the low altitudes.
Geography 10/18/23
Same things: Air Pressure Atmospheric Pressure Barometric Pressure
Weight of the Atmosphere: 6 Quadrillion Tons
Weight per unit area: 14.7 lbs per square inch
We measure are pressure with a device called a Barometer
Mercurial Barometer - Called that because it uses Mercury Air pressure as measured by the Mercurial Barometer: 29.92 Inches of Mercury (Hg)
Aneroid Barometer: Has a small capsule with flexible sides that has had the air pumped out of it. Air pressure as measured by the Aneroid Barometer: 1013.2 Millibars (mb)
Normal air pressure at sea level: 14.7 lbs per square inch 29.92 inches (Mercurial Barometer) 1013.2 mb (Aneroid Barometer)
Air pressure decreases with increasing altitude Rate of decrease: 1/30 per 900 feet
Geography 10/23/23
High Pressure Centers
Called Anticyclones
Symbol on a weather map = H or High
Generally results in fair weather (No rain or snow, depending on season)
Low Pressure Centers
Called Cyclones
Symbol on a weather map = L or Low
Generally results in poor weather (rain or snow, depending on season)
Hurricanes and Tornadoes represent centers of extremely low pressure.
All tornadoes are cyclones, but not all cyclones are tornadoes.
Weather Map
Constantly changes from day to day as pressure centers are on the move (West to East).
Wind and Air pressure are intimately linked.
Wind: Air in motion. It is a vector quantity, meaning we have to measure speed and direction.
Anemometer: An instrument for measuring the speed of the wind, or of any current of gas.
Consists of 3 cups that freely spin, the faster the wind is blowing, the faster the spinning. That information is transferred and measured. The faster the wind, the faster the cups spin, the faster the speed shows.
Wind speed is reported in MPH for us. Weather service measures wind speed in knots.
A wind vane/weather vane is an instrument used for showing the direction of the wind.
Wind direction is always expressed by the direction FROM which the wind is blowing.
If the weather channel says there is a North wind, the wind is coming FROM the North
These instruments should be mounted up high, so there is nothing blocking them.
Hand held Anemometer
Used to determine wind speed out in the field.
Wind sock
Used in aviation (smaller airports, private planes) Wind enters large opening, funnels through to small opening on the other end.
Measures the direction the wind is blowing TO.
Factors affecting wind speed
Steepness of pressure gradient:
Pressure Gradient: The difference between high pressure and low pressure.
If there is a big difference between high pressure and low pressure (Steeper gradient), the air is going to move very fast. Same idea for other way around.
Friction:
Slows wind speed down
Nature of surface plays a role in friction
Factors affecting wind direction
Pressure Gradient Orientation:
The surface arrangement of the pressure centers.
Pressure centers are constantly on the move. As they move, they change the direction of wind
Wind is ALWAYS going to blow from the HIGH to the LOW.
Coriolis Force (Sometimes called Coriolis Effect):
The deflection in the course of a moving object, especially gases and fluids, brought about by the rotation of the Earth.
Effects ALL moving objects, but especially gases and fluids.
Deflection is to the right of the intended path in the Northern Hemisphere; to the left in the Southern Hemisphere.
The strength of the Coriolis force increases with increasing latitude.
Non existent at the Equator; In full force at the poles.
Geography 10/25/23
Coriolis Force: The Deflection in the course of a moving object, especially gases and fluids, brought about by the rotation of the Earth.
Deflection is to the right of the intended path in the Northern Hemisphere; To the left in the Southern Hemisphere.
The strength of the Coriolis Force increases with increasing latitude
Non existent at the equator; in full force at the poles.
'H' Indicates point of highest pressure (All areas around that will be lower pressure).
Divergence: The process of air moving AWAY from a specific location. Convergence: The process of air moving TOWARD a specific location.
Northern Hemisphere: Clockwise airflow around high pressure centers. Southern Hemisphere: Counter clockwise airflow around high pressure centers.
Conterminous: Having a common border. Refers to United States (Excluding Alaska and Hawaii)
Geography 10/27/23
Trade Winds: Best developed wind system in the world.
Blow between the 2 strongest pressure belts (Subtropical Highs and Equatorial Lows).
Most extensively developed wind system (cover more surface than any other wind system).
Consistent in both speed and direction.
Excellent sailing winds.
Westerlies
Winds of the temperate world
Wind of the conterminous United States
All of our weather systems come from the west
Polar Easterlies
Weakest of the major surface wind systems
They blow between the two weakest pressure belts
Affect no major population centers
Winds Within the Pressure Belts
Equatorial Low: Strong winds with thunderstorms, otherwise calm. Sometimes referred to as the "doldrums" or "ITCZ" (Intertropical convergence zone).
Polar Highs: Generally light winds although sometimes strong in Antarctica.
Subpolar Lows: Strong winds associated with storms, otherwise calm.
Subtropical Highs: Characterized by variable light winds and calms. Sometimes referred to as the "Horse Latitudes".
Wind Records are usually based on estimates of damage (wind speeds are too high and damage anemometers).
Sustained Wind: Constant speed, no let up.
Gust: A momentary increase in wind speed.
Hurricanes: Typically 75-120 MPH, optimally 200 MPH Tornadoes: Typically 100-250 MPH, optimally 300-400 MPH Highest sustained surface wind ever recorded - 231 MPH (Recorded at the top of Mount Washington).
Tornadoes have stronger winds but affect smaller areas.
100 MPH is sufficient to flip an automobile.
Mount Washington is the highest peak in the Presidential Range.
The Presidential Range refers to a prominent mountain range located in the White Mountains of New Hampshire, USA. It is named after the U.S. presidents, and it includes several notable peaks, with the highest being Mount Washington, which is famous for its extreme weather conditions.
Humidity: General term referring to the moisture in the air.
Water Vapor (Primary Greenhouse Gas) Invisible, Colorless, Odorless, Tasteless.
3 Expressions of HumidityL Absolute Humidity Specific Humidity Relative Humidity (This is the one we hear when we get weather reports)
Relative Humidity: The ratio of the amount of water vapor actually in the air (at time of measurement) to the maximum amount that the air can hold at that temperature (Expressed in %). Example: Weather report says 63% relative humidity, means the air is holding 63% of the water vapor that it can hold.
2 ways to change relative humidity: Add or subtract water vapor Change temperature
Dew Point: The temperature at which relative humidity reaches 100% (Sometimes called the Dew Point Temperature).
Geography 10/30/23
Monsoon: A seasonally reversing wind flow system characteristic of South and South East Asia
Results in a rainy Summer and a dry Winter
On-shore winds in the Summer (From ocean to land) Off-shore winds in the Winter (From land to ocean)
Reversing Wind Flow
Monsoon Flooding
Monsoon Tendency gives us our humid Summers
The Jet Stream: Serves as the steering current for surface weather disturbances.
Storms form along the polar front, low pressure centers form along the polar front.
Polar front is constantly undulating
Winds in jet stream can vary from 50 MPH to 250 MPH
Pressure Belts shift northward in summer, and shift southward in winter.
The Sahel is a region in Africa that spans across the northern part of the continent, just south of the Sahara Desert. It is a transitional zone between the arid Sahara to the north and the savannas and more fertile areas to the south.
Going over relative humidity
In melting and evaporation, heat energy is absorbed, so they are cooling processes.
When gaseous water vapor turns to liquid and when liquid freezes to solid, heat is released.
Storms get energy from heat released when water vapor condenses.
Evaporation and Condensation have much more heat energy.
Warm air holds more water vapor than cold air!
As temperature goes up, the air can hold more and more water vapor. As temperature goes down, the air can hold less and less water vapor.
Usual case: Lowest relative humidity in late afternoon and highest relative humidity in early morning.
Products of Condensation: Dew (Surface level form of condensation. Ex: Water on wind shield in morning) Fog (Collection of countless microscopic particles of water, so tiny that they remain suspended) Clouds (Same as fog, just different location, off ground) Rain/Drizzle (Molecules of water falling)
Only difference between Cloud and Fog: Cloud has to be detatched from ground. Location is different.
Products of Sublimation: Frost (Ice crystals formed directly on cold surfaces) Snow (Ice crystals falling from the sky) Ice Crystal Clouds (Cirrus) (Clouds made up entirely of ice crystals)
Geography 11/1/23
Precipitation: General term used to describe water falling from Atmosphere.
Rain Drizzle Sleet - Tiny particles of ice falling from atmosphere. Occurs usually between rain to snow or snow to rain. Good indicator of improving or deteriorating weather conditions. Freezing Rain - Rain that hits the surface as rain, and immediately freezes (Freezes on contact with the surface). (Winter only type of precipitation) Snow Hail - Ice falling from atmosphere (Summer only type of precipitation). To produce hail, there needs to be a severe thunderstorm. Can range from BB size to Baseball size.
Rain Gauge - A meteorological instrument used to measure the amount of precipitation, typically rainfall, that has fallen over a specific area during a specified period of time. Funnel that directs the collected rainwater into a graduated container or measuring tube. The depth of the water in the measuring tube provides an accurate measurement of the rainfall in millimeters or inches, depending on the scale used.
Precipitation records are always kept in liquid form.
Geography 11/6/23
Exam 2 - 11/17
The Hydrologic Cycle: The continuous or cyclical path of water from the Earth to the atmosphere and back to the surface.
Importance: The Hydrologic Cycle replenishes our water supply. If there is no Hydrologic Cycle, there would be no fresh water. All living things need fresh water.
Aquifers
3 Lakes that supply water in Baltimore:
Liberty Lake
Pretty boy reservoir
Loch raven dam
Submersible Well Pump
Well Pump System
Septic Tank:
Conventional Septic System:
Writing Assignment - Due December 6th
Categories of Clouds: Low, Middle, High, and Clouds of Vertical Extent
Cumulous Clouds - Flat bottoms represent atmospheric dew point
Cirrus Clouds:
High altitude clouds.
Made up of ice crystals.
Usually precede a warm front (means rain or snow is coming).
Cumulonimbus Cloud
Dense, towering vertical cloud, typically forming from water vapor condensing in the lower troposphere that builds upward carried by powerful buoyant air currents.
Altitude: 2,000-52,000 ft
Contrails
Formed by jets.
Rising Air (Characteristics):
Temperature goes down
Pressure goes down
Volume expands
Relative humidity goes up
Descending Air (Characteristics):
Temperature goes up
Pressure goes up
Volume contracts
Relative humidity goes down
Geography 11/8/23
4 Types of Atmospheric Lifting:
Orographic Lifting - The rising of air over high mountains.
'Oro' as a prefix has to do with mountains
Frontal Lifting - The rising of air over weather fronts.
Fronts on a weather map:
Cold air and warm air do not get along
Warm air is always going to rise relative to the cold.
Convectional Lifting - The spontaneous rising of heated air.
Cyclonic Lifting - The upward spiral of air into the low of a well developed storm.
The characteristic of tornadoes and hurricanes.
reminder to get my vaccines
Latitude (Pressure Belts)
High Pressure Belts - N & S Subtropical Highs - N & S Polar Highs - Fair weather - Little precipitation Low Pressure Belts - Equatorial Low - N & S Subpolar Lows - Por weather - More precipitation
Continentality - Term used to describe how deep within a continent a place is located.
Example: Maryland is a coastal location, whereas Kansas is in the middle of the conterminous US.
The farther away from an ocean, the less water vapor and vise versa:
Continental Locations - Drier - Farther from oceanic water vapor source Coastal Locations - Wetter - Closer to oceanic water vapor source
Ocean Currents - Temperature of the water in the current effects the temperature of the air above the current.
Warm ocean currents flow along East coasts - East costs generally wetter Cold ocean currents flow along west coasts - West coasts generally drier
Mountain Barriers (Rainshadow Effect)
Found in high mountain regions - Windward side (facing the wind) - wetter - Leeward side (facing away from the wind) - Drier
Rainshadow Effect
Temperate Rain Forest: A type of woodland that is characterized by heavy rainfall and a mild climate. It is usually located within the temperate zone and is dominated by a mix of broad-leaved or coniferous trees. The temperate rainforest is distinguished from a tropical rainforest by the presence of a dominant tree.
World Precipitation Map
Isohyet - Lines that connect points of equal precipitation.
Precipitation plays a big role in agriculture.
Precipitation Variability - How much precipitation varies month to month, year to year. Plays a big role on what is grown in various parts of the world.
As we get farther West (more continental), precipitation variability is greater.
Air Mass - A large body of air with fairly uniform temperature and moisture characteristics.
Uniform Temperature Characteristic means if it is a cold air mass, it will be cold throughout.
Uniform Moisture Characteristic means if it is a wet air mass, it will be wet throughout.
Most Important Air Masses for the U.S.
- Maritime Tropical
- Maritime Polar
- Continental Polar
Types of Fronts
- Cold Front
- Warm Front
- Occluded Front
- Stationary Front
Geography 11/10/23
Front: Leading edge of an air mass; boundary between warm and cold air.
Cold Front: Cold air moves into warm air Occluded: Cold front catches up to and merges with a warm front. Marks the end of the midlatitude cyclone. Stationary: Fronts stop moving, airmasses and fronts stop moving. Warm front: Warm air moves into cold air
Mid Latitude Cyclone
DJ KAHLED ANOTHA ONE
Hurricane: A well developed whirl of air around a calm eye. Hurricane Season June 1st to November 30th
Hurricane Fran:
Hurricane Eye is characterized as completely calm weather.
Hurricanes form in all of the tropical oceans of the world except for the Tropical South Atlantic ocean.
Hurricanes only form between 6 and 30 degrees North and South. Hurricanes don't form near the equator because of the Coriolis Force, and because of the cooler water temperatures.
Storm Nomenclature
Atlantic, Gulf, and Eastern Pacific: Hurricanes
Western Pacific: Typhoons
Indian Ocean: Tropical Cyclones
Storm Categorization
Wind Speed: < 40 MPH = Tropical Depression - Assigned a number < 74 MPH = Tropical Storm - Given a name ≥ 74 MPH = Hurricane - Same name
Saffir-Simpson Hurricane Wind Scale:
Geography 11/13/23
4 Damaging Aspects of the Hurricane
High Winds - By definition hurricane winds must be at least 74 MPH sustained. Optimally winds can reach 200 MPH.
Torrential Rains - Rainfall amounts typically 5-10 Inches, can exceed 20 Inches, and be as great as 50-60 Inches in mountainous areas. Rain usually outlasts the storm.
Large Waves - Large breakers cause beach erosion and can damage beachfront structures.
Storm Surge (Most Damaging) - The most damaging aspects of the hurricane. Most of the great historical hurricane disasters were the result of large storm surges. Can range from a couple of feet to 30 feet.
Carolina Bite - Protects from hurricane damage in the mid atlantic except for the rain.
Tornadoes occur on all continents except antarctica.
Tornado Alley - A loosely defined location of the central United States and Canada where tornadoes are most frequent. Texas up to the Dakotas.
Fujita Scale
Tornadoes are always associated with cumulonimbus clouds.
Most tornadoes are small in size.
https://www.tornadofacts.net/tornado-scale/f0-tornado.html
Tornadoes commonly have a limited path of destruction.
Cumulonimbus clouds are associated with thunderstorms; occur in the tropics.
Squall Line - A line of severe thunderstorms that can form along or ahead of a cold front. These lines are often characterized by a narrow band of intense, active thunderstorms with strong winds, heavy rain, and sometimes tornadoes. Squall lines can extend for hundreds of miles and are associated with rapidly changing weather conditions.
If you can hear the thunder: you are within 15 miles of the storm.
If you can see the lightning: count 5 seconds for every mile, starting at when you see the lightning strike, and ending count when you hear thunder.
Geography 11/15/23
Air Masses can change their characteristics as they move.
Cold Air Masses that move south might become warm; Dry air masses might become wet.
Classic Example of Air Mass Modification: Great Lakes Effect (Lake Effect).
Great Lakes Effect:
Happens in the winter time primarily.
Continental Polar Air Mass (Cold Dry Air Mass) moves southward and over the great lakes.
As dry air mass moves over lake, water in lake causes warm air to rise, causing snow to fall.
Snowbelts occur on windward side.
Great Lakes Effect is an example of Air Mass Modification.
Climate Classification:
Climate: The long-term patterns of temperature, humidity, wind, precipitation, and other atmospheric conditions in a particular region.
The Most widely used climate classification system in use is the: KOPPEN SYSTEM
One could argue that every area has its own climate.
In the Koppen Climate System, we identify a dozen major climate groups, and each major group has 2 or 3 climate types.
Map of World Climates using the Koppen System:
Humid Subtropical: Baltimore's Climate Group
Highland Climate:
A number of climates existing in close proximity.
Found in high mountainous areas.
Climate Data can be presented in a number of ways.
Climograph:
Paleoclimatology: The study of prehistoric climates.
The Last Glacial Advance:
Climate can also change by movement of continents.
Paleoclimatology
Methods of Determining Past Climates:
- Dendrochronology - Tree Ring Analysis - Oxygen Isotope Analysis - 18^O/16^O Ratio - Oceanic Sediments - Ice Cores - Pollen Analysis - Radiocarbon Dating
Geography 11/20/23
Writing Assignment due December 6th
Geologic Time - The age of the Earth (4.6 Billion Years)
Geologic Time Scale
We don't know much about the Precambrian because there were not many fossils.
Dinosaurs - Dinosaurs ruled the Earth for over 200 million years. Humans have only been around for 3-4 million years.
Paleontologists can take bones found and make a reconstructed skeleton.
Archaeopteryx - Modern birds might be the descendants of dinosaurs (very similar skeletons).
Core - (Inner and Outer) - About 4400 miles in diameter. Inner core - solid Outer core - liquid
Mantle - About 1800 miles thick. Largest portion of the Earth's interior. Rocks of the mantle exhibit a plastic type behavior (easily deformed).
Crust - 2.5-40 miles thick Thinnest under the ocean (oceanic crust) Thickest under continents (continental crust)
Both the density and temperature increase towards the center of the Earth.
Temperature of core of earth is around 5000 degrees.
Earth's temperature comes from Radioactive Decay and residual heat formation.
Geography 11/27/23
Crust of Earth is made up of rock, but we don't necessarily see that rock.
Below topsoil is clay
Below clay is stones (from bedrock)
Rocks -> Minerals -> Elements
Types of rock:
Igneous
Sedimentary
Metamorphic
Igneous - Formed by the cooling of molten rock (occurring underground)
Granite is the best known Igneous rock.
Granite is very hard and durable.
Size of crystals is determined by the speed at which the rock cools down underground. Slower cooling = Larger crystals and Faster cooling = Smaller crystals
Basalt - The cooling is very fast, not making any visible large crystals.
Usually ground up into smaller pieces, used on railroad tracks.
Pumice - Product usually of volcanic eruptions, cooling almost immediately after eruption, trapping air in it.
Sedimentary rocks - Formed of sediments Particles of rock Shells Vegetative material
Most common sedimentary rock - Limestone
Fossiliferous Limestone At the bottom of the ocean, the sea floor is composed of shells and bones that are called ooze, but Lithify and become limestone.
Lithify - transform (a sediment or other material) into stone.
Sandstone - from the bottom of deserts, from wind blown soil is aeolian sandstone.
Coal is the lithifies remains of plants.
Metamorphic Rocks: Changed shape Most igneous and sedimentary rocks have their metamorphic counterparts.
Gneiss - Metamorphosed Granite
Schist - Has a very laminar structure
Marble - Metamorphosed Limestone
Metamorphosed is from exposed to additional stress and pressure.
Result of prehistoric plants Coal, Oil, and Natural gas. Often found in same area together
Formed during carboniferous period
Coal Mining
Deep Shaft Mining if coal seam deep in surface. Surface Mining AKA Strip Mining when coal seam is near the surface.
Geography 11/29/23
All 3 of the fossil fuels are usually found together.
3 Major Producing Areas in the United States: Gulf of Mexico, Gulf Coast States (Particularly Texas), and the North Slope of Alaska
Trans-Atlantic Pipeline System
Keystone Pipeline
Three Physiographic (Geologic) Provinces: - Atlantic Coastal Plain - Piedmont (Plateau) - Valley and Ridge
Geography 12/1/23
Atlantic Coastal Plain
In Maryland:
All of Maryland on the Delmarva Peninsula and the western shore adjacent to the bay.
Loose alluvial soils and sediments.
Delmarva Farmland: listen to recording to hear
Delmarva Poultry Farm: listen to recording to hear
Blackwater NWR (National Wildlife Refuge): Largest unbroken wetland on the east coast (26,000 acres).
Piedmont
In Maryland:
From fall line to Blue Ridge mountains
Mostly metamorphic rock
Hills and Valleys
Carroll County Piedmont
Frederick County Piedmont
Valley and Ridge Province
In Maryland:
From Blue Ridge mountains to western border of state
Mostly sedimentary rock
Garret County Farmland: Livestock principle farmland, fruit
The Narrows: A water gap
Volcanic Dyke at Mary's Rock Tunnel
a RIG originally
Fall Line: The Geologic boundary between the Piedmont and the Atlantic Coastal Plain.
Potomac River Upstream: Splits between Maryland and Virginia
Great Falls of the Potomac
Cultural Significance: Falling water provided as power for electricity during Industrial Revolution.
Grist Mills
Ground corn, wheat, and other grains into usable food products such as flours and meals
Many Grist Mills once existed in Baltimore County
Owing's Upper Mill (1791)
"Groff's Mill"
Oldest and largest mill building surviving in Baltimore County
Woodberry Mills in Hampden
The Woodberry Mills in their day, at the height of production, were the worlds largest manufacturers of Cotton duck
Cotton duck used in sails
Wilkins and Rodgers
Ellicott City, Maryland
Fall Line Cities
Geography 12/4/23
Alfred Wegner
Theory of Continental Drift (1915) - Continents at one time were all together as a super continent called Pangea (All Earth).
Tectonic Plates: Massive slab of solid rock made up of Earth's lithosphere (crust and upper mantle). Also called lithospheric plate.
Found the rocks in the center of Atlantic ocean were much younger than the rocks on the edge of the Atlantic ocean.
Rift: Plates pulling away from each other.
Mid Atlantic Ridge
Plate Boundary: Boundaries between plates Rift: Plates pulling away from each other Crack forms and exposes molten Forms mid ocean ridge (under water mountain range)
Iceland: Iceland is facing a potential volcanic eruption that could happen with just 30 minutes warning. The country sits on the Mid-Atlantic Ridge, where two tectonic plates are moving apart. This causes magma to rise to the surface and create pressure.
Plate Collision: Plates colliding with one another.
Constant collisions
Mount Everest
Subduction Zone: One plate diving under another. Another example of plates coming together, but different from plate collision because one plate is significantly weaker than the other.
Constant collision
Pacific Ring of Fire: The coastlines of the Pacific Ocean characterized by numerous volcanoes and earthquake activity.
Numerous volcanoes and earthquakes found in this area.
Geography 12/6/23
Mount Aconcagua
Mexican Volcano
Japan's Mount Fuji
Mount Pinatubo 1991 - Largest volcanic eruption of the 20th century
Plate Boundaries continued
Transform Fault - Plates moving side to sid
San Andreas Fault - Most researched transform fault in the world, because it passes through heavily populated areas.
Earthquakes are common along active faults
Earthquake - Ground shaking energy released by sudden movement of the Earth's crust. Usually the result of displacement along a fault.
*** Seismology - The science that studies earthquakes *** Seismograph - Instrument used to record earthquakes Seismogram - A tracing of earthquake's energy
Portable Seismograph
Earthquake Terms
Focus - The underground center of motion Epicenter - The point on the Earths surface directly above the focus
Charles Richter
Richter Scale - Rating Earthquake intensity.
Open ended logarithmic scale
As you go higher up on scale, intensity of earthquakes become much higher.
Earthquake Hazards
Building Collapse
Fire
Landslides
Tsunami
Soil Liquefaction - Fill and soft sediments become liquefied due to ground shaking.
Anchorage Alaska 1964 - Highest rated earthquake on Richter Scale (9.4).
Marina District 1989 - Building collapsed, natural gas pipe ruptured.
Tsunami - Seismic sea wave generated by an earthquake under the sea floor.
Indian Ocean Tsunami - December 2004 Tohoku Earthquake - March 2011
California's Subsidiary Faults
Loma Prieta Earthquake - October 1989
New Madrid, Missouri
3 Earthquakes December 1811 - February 1812
Predicting Earthquakes - No success
Earthquakes in Maryland
Most 2 Magnitude or less
Largest Earthquake - 3.8 Phoenix, MD 1939
Many felt in Maryland occur elsewhere
Great Baltimore Fire - 1904
Downtown destroyed
Geography 12/8/23
Landform Producing Forces
Tectonic Forces - Forces that build up landforms.
Endogenetic Forces - Forces that originate from within the Earth.
Tectonic Forces
A. Diastrophism (Solid state, movement of solid rock)
1. Folding (Bending of rock)
2. Faulting (Breaking of rock)
B. Vulcanism (Molten state; 2000 degrees or more)
1. Intrusive (Movement of magma beneath the surface)
2. Extrusive (Movement of lava and other products above the surface)
Black Hills - The Black Hills is an isolated mountain range rising from the Great Plains of North America in western South Dakota and extending into Wyoming, United States.
Mount Rushmore is here; sculpture chose this area because of the granite there.
Volcano Cutaway
Production of Eruptions
Strato volcanoes
Pyroclastic flow - A pyroclastic flow is a fast-moving mixture of hot gas and volcanic matter, such as ash and rock fragments, that travels down the slopes of a volcano during an eruption. These flows are extremely dangerous and can reach high speeds (100+ MPH).
In the conterminous United States (the 48 contiguous states), you can find volcanoes primarily in the Cascade Range in the Pacific Northwest. The Cascade Range extends from northern California through Oregon and Washington to southern British Columbia in Canada. Notable volcanoes in this region include Mount St. Helens, Mount Hood, Mount Rainier, and Mount Shasta.
Geomorphology - The study of landforms.
Forces which wear down
Exogenetic forces (From outside the Earth)
Degradation - The wearing down of rock material
1. Weathering (Breaking down)
a. Chemical
b. Physical
Chemical Weathering occurs primarily through acid precipitation.
Pollutants mix with the water in the air to produce acid, which destroys rock when it comes in contact
Frost wedging
Plant Roots can do the same thing
Rodents also do their part
Mountain Bikes also contribute to physical weathering
2. Erosion (Removal)
a. Water
b. Wind
c. Ice
Stream Erosion
Volume plays a big role. The greater the volume of the water, the more sediments are picked up.
Wind Erosion
Only found in dry environments
Dunes
Mountain Glaciers
A glacier is a river of ice; Mountain glaciers start off in higher elevations with heavy snow, which compacts into ice and over time works it way down the slope, picking up on rocks and boulders, grinding against the ground, being transported down the slope by the ice and eventually to the ocean.
Calving - The process by which large chunks of ice break off from the edge of a glacier and fall into the water, forming icebergs.
Most of the ice from a glacier is under the water because of the density of the ice.
North American Ice Sheet
Greenland
All of the ice in Greenland will probably be gone in the next century or two
b. Aggradation (Depositing) (Aggradational Landform examples below)
1. Beaches (Example: Ocean City)
2. Deltas - Formed where a major river enter into a larger body of water; Deltas feature very fertile soil, usually flat.
3. Dunes
William Morris Davis - By training, he was a geomorphologist. His specialty was streams and rivers.
Geomorphic Cycle - Goes through stages, similar to human conditions (minus the rejuvenation stage).
Youthful Landform - MT. Everest because it is growing, getting taller
Mature Landform - The Rockies because they are not growing
Old Age Landform - Appalachian because it is slowly deteriorating. Over time, it will completely disappear. (No tectonic activity)
Rejuvenation - Plate collision can cause this
Latitude - East/West lines that determine North/South locations.
Each parallel to the next
Sometimes called parallels
Expressed in degrees
90 degrees is the maximum amount of latitude
Longitude - North/South lines that determine East/West locations
Are not parallels; converge at the poles
Sometimes called meridians
Expressed in degrees
Greenwich Meridian Prime Meridian
0 degrees longitude
Line from which lines of longitude are numbered
Whenever you write coordinates, by convention, latitude MUST COME FIRST!
Latitude FIRST, Longitude SECOND
Tropic of Cancer
23.5 Degrees North
The northern most point on earth that experiences the direct rays of the sun
Tropic of Capricorn
23.5 Degrees South
The southern most point on earth that experiences the direct rays of the sun
Arctic Circle
66.5 Degrees North
The farthest point from the North Pole, in the northern hemisphere, that experiences at least one day when the sun does not rise and at least one day when the sun does not set.
Antarctic Circle
66.5 Degrees South
The farthest point from the South Pole, in the southern hemisphere, that experiences at least one day when the sun does not rise and at least one day when the sun does not set.
9/8/23
International Dateline - Line marking the point where each day ends and begins
24 time zones
Maps - Primary tool of the geographer
A map is a scaled representation of all 4 portions of the earths surface.
All maps in geography are reductions
CHECK PHONE PHOTOS FROM 9/8/23 FOR PICTURE OF EXAMPLE OF THE GRAPH THING
3 Methods of Scale Representation - Three ways that the cartographer can present map scale to us
Graphic Scale
Stated Scale - 1 inch = 1 mile
Representative Fraction (RF) - 1 : 24,000 (1 unit on the map is 24,000 of that same unit in real life)
All three shown in legend
9/11/23
U.S.G.S - United States Geological Survey
IN charge of overseeing any geological issue in the country, even the world. Floods, earthquakes, tidalwaves, etc...
Our Country's Mapping Agency
Small Scale Maps
Show a lot of area - little detail
EX: World Map
R.F. = 1:24,000,000
Large Scale Maps
Little area - lot of detail
R.F. = 1:24,000
3 Basic Types of Maps
Planimetric
Thematic
Topographic
Planimetric
Show two dimensional information only (2D)
No reference to altitude (Not needed)
EX: Road Map
Thematic (Topical) Maps
Present a theme or topic
Maybe of greatest use in presenting geographic information
Topographic Maps
Show Three Dimensional Information (3D)
Altitude Values are shown
Topographic from Topography
Topography - The surface features of the earth and their arrangement.
Ways to show 3D information
Raised Relief
Colors
Contour Lines
Raised Relief
Colors
Contour Lines - (Isolines) Connects points of equal altitude
9/13/23
Map Projections
The way that the surface features of the Earth are projected onto the map surface.
Great Circle
A great circle is any line which bisects the Earth into two equal half spheres
Significance - Any portion of a great circle represents the shortest distance between two points on Earth.
Great Circle Routes
9/15/23
The Universe - All Things
Cosmology - The study of the Universe
Astronomy - The study of space
Speed of Light - 186,000 Miles Per Second
The Light Year - The distance that light will travel in one year's time.
6,000,000,000,000 Miles
The Light Year is a measure of DISTANCE, NOT a measure of TIME!
How old is the Universe?
The Big Bang - Occurred between 13.6 - 14.0 billion years ago
How big is our universe?
The distance to the edge of the known universe is estimated to be about 14 billion light years
Galaxies - An organized group of stars.
Andromeda Galaxy
Barred Spiral
Hubble Deep Field Photo
Ring Nebula
9/18/23
Formation of Planets
Proto Earth
Terrestrial Planets
Relatively small size, rocky composition, dense, few moons
Mercury, Venus, Earth, Mars
Jovian Planets
Large in size, gaseous composition, not dense, many moons, ring systems
Jupiter, Saturn, Uranus, Neptune
The Solar System
Asteroids
Pieces of space rocks
Asteroid Belt
Comets
Meteors
Geography 9/20
Asteroids
Asteroid Belt
Comets
Comet Hale-Bopp
Comet 67P
Meteor
Meteors that survive the burn and reach the ground are called Meteorites.
Meteor Showers
Geography 9/22/23
Earth
Diameters of the Earth
Equatorial Diameter - 7,926 Miles
Polar Diameter - 7,900 Miles
26 Mile Difference
Polar Flattening
Relief
The difference in altitude between the highest and lowest points of an area or region
Relief of the world
Highest Point - Mount Everest: 5.5 Miles High
Lowest Point - Marianas Trench: 7.0 Miles Deep
Total Relief of the World - 12.5 Miles
Relief of Maryland
Lowest Point - Ocean City, MD: Sea Level: 0 Feet
Highest Point - Backbone Mountain: 3,360 Feet
Total Relief of Maryland - 3,360 Feet
Types of Terrain
Low Relief - Ex. Maryland's Eastern Shore
High Relief - Ex. Mountains in Western Maryland
High Rugged Relief - Ex. Rocky Mountains
Geography 9/25/23
Rotation
The spinning of the Earth around it's axis.
Axis - Imaginary line passing through the center of the Earth and intersecting the surface at the poles.
Period and Speed of Rotation
Period - 24 Hours (1 Day)
Speed - Varies with Latitude
Fastest at equator - 1040 MPH
Speed decreases with increasing latitude
At the poles - 0 MPH
Revolution
The movement of the Earth in its orbit around the Sun.
The Earth describes an elliptical orbit around the Sun.
93,000,000 Miles = 1 A.U. (Astronomical Unit)
Period and Speed of Revolution
Period - 365.25 Days (1 Year)
Speed - Varies depending on position in orbit.
Slower at Aphelion
Faster at Perihelion
Average speed - 67,000 MPH
The Seasons
The seasons are caused by a combination of the Earth's revolution and its inclination (tilt) to the ecliptic.
The Seasons
Vernal Equinox - First Day of Spring - March 21
Summer Solstice - First Day of Summer - June 21
Autumnal Equinox - First Day of Fall - Sept 21
Winter Solstice - First Day of Winter - Dec 21
The Seasons
The seasons are caused by a combination of the Earth's revolution and its inclination (tilt) to the ecliptic.
Geography 9/27/23
The Seasons
The Seasons are caused by a combination of the Earth's revolution and its inclination (tilt) to the ecliptic
Constellation
An arbitrary grouping of stars that today serve as reference points in the night sky
Geography 10/2/23
The Sun
Sun's Energy
Produced by Nuclear Fusion
4 Hydrogen atoms fused to form one Helium atom
The Sun is estimated to be converting Hydrogen to Helium at 400,000,000 tons per second
Electromagnetic Spectrum
Composition of Sun's Energy
51% Infrared or Longer Wavelength
41% Visible Light
8% Ultraviolet or Shorter Wavelength
Distribution of Insolation
30% - Wasted (Not Used)
20% - By Clouds
6% - By Particulates (Dust)
4% - By Surface
Insolation
In - Incoming
Sol - Solar
Ation - Radiation
Distribution of Insolation
Distribution of Insolation (Continued)
70% - Absorbed (Used by Earth System)
19% - By Clouds
51% - By Surface
Albedo
The amount of reflectance of an object or substance
Earth's Albedo = 30%
Geography 10/4/23
Primary Gases (Nonvariable Gases)
Nitrogen (N2) - 78%
Oxygen (O2) - 21%
Argon (Ar) - 1%
Important Long Term Variable Gases
- Carbon Dioxide (CO2) (Triatomic)
Important Greenhouse Gas
Essential component in the Carbon Cycle
Needed by plants
- Ozone (O3) (Triatomic)
An irritant and pollutant at the surface
Blocks UV radiation aloft
Trace Gases
- Examples:
Helium
Radon
Sulfur Dioxide
Carbon Monoxide
Methane
Thousands of others
Short Term Variable Constituents
Water Vapor (H2O)
Important Greenhouse Gas
Essential to the Hydrologic (Water) Cycle
Particulates (Dust)
Essential to the Hydrologic (Water) Cycle
Cooling effect on Atmospheric Temperatures
Geography 10/6/23
Troposphere
Temps go down with altitude
Tropopause - Upper boundary of the Troposphere
Troposphere is 5-11 miles thick
Stratosphere
Temps go up with altitude
Protective layer of ozone concentrated here
Stratopause - The upper boundary of the Stratosphere
Stratopause located at 30 miles above the surface.
Mesosphere
Temps go down with altitude
Mesopause - Upper boundary of mesosphere
Mesopause located 50 miles above surface
Zone of meteor disintegration
Thermosphere
Temps go up with altitude
No distinct upper boundary
Zone of the aurora
Aurora Borealis - Northern hemisphere Aurora Australis - Southern hemisphere
Geography 10/9/23
Weather
The condition of the atmosphere with respect to the weather elements for a SHORT period of time
Climate
The range of weather possibilities and probabilities for LONG periods of time
The Weather Elements
Temperature
Air Pressure
Wind
Moisture
Air Masses
Storms
Atmospheric Temperatures:
The Atmosphere is warmed by the surfaces of the Earth utilizing Sun's energy
Earth's surface absorbs Sun's energy... and converts it to heat energy... and radiates it out to atmosphere
Some heat energy is lost to space... most is trapped in the atmosphere by the "Greenhouse Effect"
The Greenhouse Effect
The heat trapping ability of the Earth's atmosphere
Primary Greenhouse Gases
Carbon Dioxide - CO2
Water Vapor - H2O
Methane - CH4
Geography 10/11/23
Average Noon Sun Angle *** (VERY IMPORTANT)
Latitude - Generally speaking temps decrease with increasing latitude.
Season - Lower sun angles in winter; higher sun angles in summer (When sun is higher up, its more concentrated on one area; when sun is lower, its more spread out)
Land/Water Distribution
Northern Hemisphere - 52% Water (Ocean), 48% Land
Southern Hemisphere - 88% Water (Ocean), 12% Land
Temperatures more evenly distributed in Southern Hemisphere
Isothermal Map
Isotherm - Another example of an Isoline (Lines which connect points of equal value)
An Isotherm is a line that connects points of equal TEMPERATURE
Ocean Currents
Warm Currents - Flow along East coasts of continents
Cold Currents - Flow along West coasts of continents
East Coasts tend to be warmer
West Coast weather generally more stable
Gyres - A large system of rotating ocean currents.
Global Heat Balance - The global heat balance is the balance between incoming and outgoing heat on Earth. (Ocean currents mix warmer water with cooler water to balance the temperatures)
Altitude
Normal Lapse Rate - Average rate at which temperature goes down with altitude. Temperatures decrease 3.5 Degrees F/1,000 Feet
High mountainous areas are colder
Factors Affecting Temperature Distribution (RECAP)
Average Noon Sun Angle (MOST IMPORTANT)
Land/Water distribution
Ocean Currents
Altitude
Geography 10/16/23
Wind Chill - The subjective amount of cold brought about by the combination of temperature and wind speed. (Wind makes it feel colder)
Wind Chill Index
Heat Index - The subjective amount of heat brought about by the combination of temperature and humidity. (The humidity makes it feel hotter)
Blank area is where dewpoint > 85F
Radiation - Heat transfer without contact Conduction - Heat transfer with contact Convection - Heat transfer through movement
Urban Heat Island - When cities replace natural land cover with dense concentrations of pavement, buildings, and other surfaces that absorb and retain heat.
Annual Temperature Range - The difference between the hottest and the coldest months by taking monthly mean temperatures in each case.
Changes seasonally
Highest annual temperature ranges are found in the high altitudes. Lowest annual temperature ranges are found in the low altitudes.
Geography 10/18/23
Same things: Air Pressure Atmospheric Pressure Barometric Pressure
Weight of the Atmosphere: 6 Quadrillion Tons
Weight per unit area: 14.7 lbs per square inch
We measure are pressure with a device called a Barometer
Mercurial Barometer - Called that because it uses Mercury Air pressure as measured by the Mercurial Barometer: 29.92 Inches of Mercury (Hg)
Aneroid Barometer: Has a small capsule with flexible sides that has had the air pumped out of it. Air pressure as measured by the Aneroid Barometer: 1013.2 Millibars (mb)
Normal air pressure at sea level: 14.7 lbs per square inch 29.92 inches (Mercurial Barometer) 1013.2 mb (Aneroid Barometer)
Air pressure decreases with increasing altitude Rate of decrease: 1/30 per 900 feet
Geography 10/23/23
High Pressure Centers
Called Anticyclones
Symbol on a weather map = H or High
Generally results in fair weather (No rain or snow, depending on season)
Low Pressure Centers
Called Cyclones
Symbol on a weather map = L or Low
Generally results in poor weather (rain or snow, depending on season)
Hurricanes and Tornadoes represent centers of extremely low pressure.
All tornadoes are cyclones, but not all cyclones are tornadoes.
Weather Map
Constantly changes from day to day as pressure centers are on the move (West to East).
Wind and Air pressure are intimately linked.
Wind: Air in motion. It is a vector quantity, meaning we have to measure speed and direction.
Anemometer: An instrument for measuring the speed of the wind, or of any current of gas.
Consists of 3 cups that freely spin, the faster the wind is blowing, the faster the spinning. That information is transferred and measured. The faster the wind, the faster the cups spin, the faster the speed shows.
Wind speed is reported in MPH for us. Weather service measures wind speed in knots.
A wind vane/weather vane is an instrument used for showing the direction of the wind.
Wind direction is always expressed by the direction FROM which the wind is blowing.
If the weather channel says there is a North wind, the wind is coming FROM the North
These instruments should be mounted up high, so there is nothing blocking them.
Hand held Anemometer
Used to determine wind speed out in the field.
Wind sock
Used in aviation (smaller airports, private planes) Wind enters large opening, funnels through to small opening on the other end.
Measures the direction the wind is blowing TO.
Factors affecting wind speed
Steepness of pressure gradient:
Pressure Gradient: The difference between high pressure and low pressure.
If there is a big difference between high pressure and low pressure (Steeper gradient), the air is going to move very fast. Same idea for other way around.
Friction:
Slows wind speed down
Nature of surface plays a role in friction
Factors affecting wind direction
Pressure Gradient Orientation:
The surface arrangement of the pressure centers.
Pressure centers are constantly on the move. As they move, they change the direction of wind
Wind is ALWAYS going to blow from the HIGH to the LOW.
Coriolis Force (Sometimes called Coriolis Effect):
The deflection in the course of a moving object, especially gases and fluids, brought about by the rotation of the Earth.
Effects ALL moving objects, but especially gases and fluids.
Deflection is to the right of the intended path in the Northern Hemisphere; to the left in the Southern Hemisphere.
The strength of the Coriolis force increases with increasing latitude.
Non existent at the Equator; In full force at the poles.
Geography 10/25/23
Coriolis Force: The Deflection in the course of a moving object, especially gases and fluids, brought about by the rotation of the Earth.
Deflection is to the right of the intended path in the Northern Hemisphere; To the left in the Southern Hemisphere.
The strength of the Coriolis Force increases with increasing latitude
Non existent at the equator; in full force at the poles.
'H' Indicates point of highest pressure (All areas around that will be lower pressure).
Divergence: The process of air moving AWAY from a specific location. Convergence: The process of air moving TOWARD a specific location.
Northern Hemisphere: Clockwise airflow around high pressure centers. Southern Hemisphere: Counter clockwise airflow around high pressure centers.
Conterminous: Having a common border. Refers to United States (Excluding Alaska and Hawaii)
Geography 10/27/23
Trade Winds: Best developed wind system in the world.
Blow between the 2 strongest pressure belts (Subtropical Highs and Equatorial Lows).
Most extensively developed wind system (cover more surface than any other wind system).
Consistent in both speed and direction.
Excellent sailing winds.
Westerlies
Winds of the temperate world
Wind of the conterminous United States
All of our weather systems come from the west
Polar Easterlies
Weakest of the major surface wind systems
They blow between the two weakest pressure belts
Affect no major population centers
Winds Within the Pressure Belts
Equatorial Low: Strong winds with thunderstorms, otherwise calm. Sometimes referred to as the "doldrums" or "ITCZ" (Intertropical convergence zone).
Polar Highs: Generally light winds although sometimes strong in Antarctica.
Subpolar Lows: Strong winds associated with storms, otherwise calm.
Subtropical Highs: Characterized by variable light winds and calms. Sometimes referred to as the "Horse Latitudes".
Wind Records are usually based on estimates of damage (wind speeds are too high and damage anemometers).
Sustained Wind: Constant speed, no let up.
Gust: A momentary increase in wind speed.
Hurricanes: Typically 75-120 MPH, optimally 200 MPH Tornadoes: Typically 100-250 MPH, optimally 300-400 MPH Highest sustained surface wind ever recorded - 231 MPH (Recorded at the top of Mount Washington).
Tornadoes have stronger winds but affect smaller areas.
100 MPH is sufficient to flip an automobile.
Mount Washington is the highest peak in the Presidential Range.
The Presidential Range refers to a prominent mountain range located in the White Mountains of New Hampshire, USA. It is named after the U.S. presidents, and it includes several notable peaks, with the highest being Mount Washington, which is famous for its extreme weather conditions.
Humidity: General term referring to the moisture in the air.
Water Vapor (Primary Greenhouse Gas) Invisible, Colorless, Odorless, Tasteless.
3 Expressions of HumidityL Absolute Humidity Specific Humidity Relative Humidity (This is the one we hear when we get weather reports)
Relative Humidity: The ratio of the amount of water vapor actually in the air (at time of measurement) to the maximum amount that the air can hold at that temperature (Expressed in %). Example: Weather report says 63% relative humidity, means the air is holding 63% of the water vapor that it can hold.
2 ways to change relative humidity: Add or subtract water vapor Change temperature
Dew Point: The temperature at which relative humidity reaches 100% (Sometimes called the Dew Point Temperature).
Geography 10/30/23
Monsoon: A seasonally reversing wind flow system characteristic of South and South East Asia
Results in a rainy Summer and a dry Winter
On-shore winds in the Summer (From ocean to land) Off-shore winds in the Winter (From land to ocean)
Reversing Wind Flow
Monsoon Flooding
Monsoon Tendency gives us our humid Summers
The Jet Stream: Serves as the steering current for surface weather disturbances.
Storms form along the polar front, low pressure centers form along the polar front.
Polar front is constantly undulating
Winds in jet stream can vary from 50 MPH to 250 MPH
Pressure Belts shift northward in summer, and shift southward in winter.
The Sahel is a region in Africa that spans across the northern part of the continent, just south of the Sahara Desert. It is a transitional zone between the arid Sahara to the north and the savannas and more fertile areas to the south.
Going over relative humidity
In melting and evaporation, heat energy is absorbed, so they are cooling processes.
When gaseous water vapor turns to liquid and when liquid freezes to solid, heat is released.
Storms get energy from heat released when water vapor condenses.
Evaporation and Condensation have much more heat energy.
Warm air holds more water vapor than cold air!
As temperature goes up, the air can hold more and more water vapor. As temperature goes down, the air can hold less and less water vapor.
Usual case: Lowest relative humidity in late afternoon and highest relative humidity in early morning.
Products of Condensation: Dew (Surface level form of condensation. Ex: Water on wind shield in morning) Fog (Collection of countless microscopic particles of water, so tiny that they remain suspended) Clouds (Same as fog, just different location, off ground) Rain/Drizzle (Molecules of water falling)
Only difference between Cloud and Fog: Cloud has to be detatched from ground. Location is different.
Products of Sublimation: Frost (Ice crystals formed directly on cold surfaces) Snow (Ice crystals falling from the sky) Ice Crystal Clouds (Cirrus) (Clouds made up entirely of ice crystals)
Geography 11/1/23
Precipitation: General term used to describe water falling from Atmosphere.
Rain Drizzle Sleet - Tiny particles of ice falling from atmosphere. Occurs usually between rain to snow or snow to rain. Good indicator of improving or deteriorating weather conditions. Freezing Rain - Rain that hits the surface as rain, and immediately freezes (Freezes on contact with the surface). (Winter only type of precipitation) Snow Hail - Ice falling from atmosphere (Summer only type of precipitation). To produce hail, there needs to be a severe thunderstorm. Can range from BB size to Baseball size.
Rain Gauge - A meteorological instrument used to measure the amount of precipitation, typically rainfall, that has fallen over a specific area during a specified period of time. Funnel that directs the collected rainwater into a graduated container or measuring tube. The depth of the water in the measuring tube provides an accurate measurement of the rainfall in millimeters or inches, depending on the scale used.
Precipitation records are always kept in liquid form.
Geography 11/6/23
Exam 2 - 11/17
The Hydrologic Cycle: The continuous or cyclical path of water from the Earth to the atmosphere and back to the surface.
Importance: The Hydrologic Cycle replenishes our water supply. If there is no Hydrologic Cycle, there would be no fresh water. All living things need fresh water.
Aquifers
3 Lakes that supply water in Baltimore:
Liberty Lake
Pretty boy reservoir
Loch raven dam
Submersible Well Pump
Well Pump System
Septic Tank:
Conventional Septic System:
Writing Assignment - Due December 6th
Categories of Clouds: Low, Middle, High, and Clouds of Vertical Extent
Cumulous Clouds - Flat bottoms represent atmospheric dew point
Cirrus Clouds:
High altitude clouds.
Made up of ice crystals.
Usually precede a warm front (means rain or snow is coming).
Cumulonimbus Cloud
Dense, towering vertical cloud, typically forming from water vapor condensing in the lower troposphere that builds upward carried by powerful buoyant air currents.
Altitude: 2,000-52,000 ft
Contrails
Formed by jets.
Rising Air (Characteristics):
Temperature goes down
Pressure goes down
Volume expands
Relative humidity goes up
Descending Air (Characteristics):
Temperature goes up
Pressure goes up
Volume contracts
Relative humidity goes down
Geography 11/8/23
4 Types of Atmospheric Lifting:
Orographic Lifting - The rising of air over high mountains.
'Oro' as a prefix has to do with mountains
Frontal Lifting - The rising of air over weather fronts.
Fronts on a weather map:
Cold air and warm air do not get along
Warm air is always going to rise relative to the cold.
Convectional Lifting - The spontaneous rising of heated air.
Cyclonic Lifting - The upward spiral of air into the low of a well developed storm.
The characteristic of tornadoes and hurricanes.
reminder to get my vaccines
Latitude (Pressure Belts)
High Pressure Belts - N & S Subtropical Highs - N & S Polar Highs - Fair weather - Little precipitation Low Pressure Belts - Equatorial Low - N & S Subpolar Lows - Por weather - More precipitation
Continentality - Term used to describe how deep within a continent a place is located.
Example: Maryland is a coastal location, whereas Kansas is in the middle of the conterminous US.
The farther away from an ocean, the less water vapor and vise versa:
Continental Locations - Drier - Farther from oceanic water vapor source Coastal Locations - Wetter - Closer to oceanic water vapor source
Ocean Currents - Temperature of the water in the current effects the temperature of the air above the current.
Warm ocean currents flow along East coasts - East costs generally wetter Cold ocean currents flow along west coasts - West coasts generally drier
Mountain Barriers (Rainshadow Effect)
Found in high mountain regions - Windward side (facing the wind) - wetter - Leeward side (facing away from the wind) - Drier
Rainshadow Effect
Temperate Rain Forest: A type of woodland that is characterized by heavy rainfall and a mild climate. It is usually located within the temperate zone and is dominated by a mix of broad-leaved or coniferous trees. The temperate rainforest is distinguished from a tropical rainforest by the presence of a dominant tree.
World Precipitation Map
Isohyet - Lines that connect points of equal precipitation.
Precipitation plays a big role in agriculture.
Precipitation Variability - How much precipitation varies month to month, year to year. Plays a big role on what is grown in various parts of the world.
As we get farther West (more continental), precipitation variability is greater.
Air Mass - A large body of air with fairly uniform temperature and moisture characteristics.
Uniform Temperature Characteristic means if it is a cold air mass, it will be cold throughout.
Uniform Moisture Characteristic means if it is a wet air mass, it will be wet throughout.
Most Important Air Masses for the U.S.
- Maritime Tropical
- Maritime Polar
- Continental Polar
Types of Fronts
- Cold Front
- Warm Front
- Occluded Front
- Stationary Front
Geography 11/10/23
Front: Leading edge of an air mass; boundary between warm and cold air.
Cold Front: Cold air moves into warm air Occluded: Cold front catches up to and merges with a warm front. Marks the end of the midlatitude cyclone. Stationary: Fronts stop moving, airmasses and fronts stop moving. Warm front: Warm air moves into cold air
Mid Latitude Cyclone
DJ KAHLED ANOTHA ONE
Hurricane: A well developed whirl of air around a calm eye. Hurricane Season June 1st to November 30th
Hurricane Fran:
Hurricane Eye is characterized as completely calm weather.
Hurricanes form in all of the tropical oceans of the world except for the Tropical South Atlantic ocean.
Hurricanes only form between 6 and 30 degrees North and South. Hurricanes don't form near the equator because of the Coriolis Force, and because of the cooler water temperatures.
Storm Nomenclature
Atlantic, Gulf, and Eastern Pacific: Hurricanes
Western Pacific: Typhoons
Indian Ocean: Tropical Cyclones
Storm Categorization
Wind Speed: < 40 MPH = Tropical Depression - Assigned a number < 74 MPH = Tropical Storm - Given a name ≥ 74 MPH = Hurricane - Same name
Saffir-Simpson Hurricane Wind Scale:
Geography 11/13/23
4 Damaging Aspects of the Hurricane
High Winds - By definition hurricane winds must be at least 74 MPH sustained. Optimally winds can reach 200 MPH.
Torrential Rains - Rainfall amounts typically 5-10 Inches, can exceed 20 Inches, and be as great as 50-60 Inches in mountainous areas. Rain usually outlasts the storm.
Large Waves - Large breakers cause beach erosion and can damage beachfront structures.
Storm Surge (Most Damaging) - The most damaging aspects of the hurricane. Most of the great historical hurricane disasters were the result of large storm surges. Can range from a couple of feet to 30 feet.
Carolina Bite - Protects from hurricane damage in the mid atlantic except for the rain.
Tornadoes occur on all continents except antarctica.
Tornado Alley - A loosely defined location of the central United States and Canada where tornadoes are most frequent. Texas up to the Dakotas.
Fujita Scale
Tornadoes are always associated with cumulonimbus clouds.
Most tornadoes are small in size.
https://www.tornadofacts.net/tornado-scale/f0-tornado.html
Tornadoes commonly have a limited path of destruction.
Cumulonimbus clouds are associated with thunderstorms; occur in the tropics.
Squall Line - A line of severe thunderstorms that can form along or ahead of a cold front. These lines are often characterized by a narrow band of intense, active thunderstorms with strong winds, heavy rain, and sometimes tornadoes. Squall lines can extend for hundreds of miles and are associated with rapidly changing weather conditions.
If you can hear the thunder: you are within 15 miles of the storm.
If you can see the lightning: count 5 seconds for every mile, starting at when you see the lightning strike, and ending count when you hear thunder.
Geography 11/15/23
Air Masses can change their characteristics as they move.
Cold Air Masses that move south might become warm; Dry air masses might become wet.
Classic Example of Air Mass Modification: Great Lakes Effect (Lake Effect).
Great Lakes Effect:
Happens in the winter time primarily.
Continental Polar Air Mass (Cold Dry Air Mass) moves southward and over the great lakes.
As dry air mass moves over lake, water in lake causes warm air to rise, causing snow to fall.
Snowbelts occur on windward side.
Great Lakes Effect is an example of Air Mass Modification.
Climate Classification:
Climate: The long-term patterns of temperature, humidity, wind, precipitation, and other atmospheric conditions in a particular region.
The Most widely used climate classification system in use is the: KOPPEN SYSTEM
One could argue that every area has its own climate.
In the Koppen Climate System, we identify a dozen major climate groups, and each major group has 2 or 3 climate types.
Map of World Climates using the Koppen System:
Humid Subtropical: Baltimore's Climate Group
Highland Climate:
A number of climates existing in close proximity.
Found in high mountainous areas.
Climate Data can be presented in a number of ways.
Climograph:
Paleoclimatology: The study of prehistoric climates.
The Last Glacial Advance:
Climate can also change by movement of continents.
Paleoclimatology
Methods of Determining Past Climates:
- Dendrochronology - Tree Ring Analysis - Oxygen Isotope Analysis - 18^O/16^O Ratio - Oceanic Sediments - Ice Cores - Pollen Analysis - Radiocarbon Dating
Geography 11/20/23
Writing Assignment due December 6th
Geologic Time - The age of the Earth (4.6 Billion Years)
Geologic Time Scale
We don't know much about the Precambrian because there were not many fossils.
Dinosaurs - Dinosaurs ruled the Earth for over 200 million years. Humans have only been around for 3-4 million years.
Paleontologists can take bones found and make a reconstructed skeleton.
Archaeopteryx - Modern birds might be the descendants of dinosaurs (very similar skeletons).
Core - (Inner and Outer) - About 4400 miles in diameter. Inner core - solid Outer core - liquid
Mantle - About 1800 miles thick. Largest portion of the Earth's interior. Rocks of the mantle exhibit a plastic type behavior (easily deformed).
Crust - 2.5-40 miles thick Thinnest under the ocean (oceanic crust) Thickest under continents (continental crust)
Both the density and temperature increase towards the center of the Earth.
Temperature of core of earth is around 5000 degrees.
Earth's temperature comes from Radioactive Decay and residual heat formation.
Geography 11/27/23
Crust of Earth is made up of rock, but we don't necessarily see that rock.
Below topsoil is clay
Below clay is stones (from bedrock)
Rocks -> Minerals -> Elements
Types of rock:
Igneous
Sedimentary
Metamorphic
Igneous - Formed by the cooling of molten rock (occurring underground)
Granite is the best known Igneous rock.
Granite is very hard and durable.
Size of crystals is determined by the speed at which the rock cools down underground. Slower cooling = Larger crystals and Faster cooling = Smaller crystals
Basalt - The cooling is very fast, not making any visible large crystals.
Usually ground up into smaller pieces, used on railroad tracks.
Pumice - Product usually of volcanic eruptions, cooling almost immediately after eruption, trapping air in it.
Sedimentary rocks - Formed of sediments Particles of rock Shells Vegetative material
Most common sedimentary rock - Limestone
Fossiliferous Limestone At the bottom of the ocean, the sea floor is composed of shells and bones that are called ooze, but Lithify and become limestone.
Lithify - transform (a sediment or other material) into stone.
Sandstone - from the bottom of deserts, from wind blown soil is aeolian sandstone.
Coal is the lithifies remains of plants.
Metamorphic Rocks: Changed shape Most igneous and sedimentary rocks have their metamorphic counterparts.
Gneiss - Metamorphosed Granite
Schist - Has a very laminar structure
Marble - Metamorphosed Limestone
Metamorphosed is from exposed to additional stress and pressure.
Result of prehistoric plants Coal, Oil, and Natural gas. Often found in same area together
Formed during carboniferous period
Coal Mining
Deep Shaft Mining if coal seam deep in surface. Surface Mining AKA Strip Mining when coal seam is near the surface.
Geography 11/29/23
All 3 of the fossil fuels are usually found together.
3 Major Producing Areas in the United States: Gulf of Mexico, Gulf Coast States (Particularly Texas), and the North Slope of Alaska
Trans-Atlantic Pipeline System
Keystone Pipeline
Three Physiographic (Geologic) Provinces: - Atlantic Coastal Plain - Piedmont (Plateau) - Valley and Ridge
Geography 12/1/23
Atlantic Coastal Plain
In Maryland:
All of Maryland on the Delmarva Peninsula and the western shore adjacent to the bay.
Loose alluvial soils and sediments.
Delmarva Farmland: listen to recording to hear
Delmarva Poultry Farm: listen to recording to hear
Blackwater NWR (National Wildlife Refuge): Largest unbroken wetland on the east coast (26,000 acres).
Piedmont
In Maryland:
From fall line to Blue Ridge mountains
Mostly metamorphic rock
Hills and Valleys
Carroll County Piedmont
Frederick County Piedmont
Valley and Ridge Province
In Maryland:
From Blue Ridge mountains to western border of state
Mostly sedimentary rock
Garret County Farmland: Livestock principle farmland, fruit
The Narrows: A water gap
Volcanic Dyke at Mary's Rock Tunnel
a RIG originally
Fall Line: The Geologic boundary between the Piedmont and the Atlantic Coastal Plain.
Potomac River Upstream: Splits between Maryland and Virginia
Great Falls of the Potomac
Cultural Significance: Falling water provided as power for electricity during Industrial Revolution.
Grist Mills
Ground corn, wheat, and other grains into usable food products such as flours and meals
Many Grist Mills once existed in Baltimore County
Owing's Upper Mill (1791)
"Groff's Mill"
Oldest and largest mill building surviving in Baltimore County
Woodberry Mills in Hampden
The Woodberry Mills in their day, at the height of production, were the worlds largest manufacturers of Cotton duck
Cotton duck used in sails
Wilkins and Rodgers
Ellicott City, Maryland
Fall Line Cities
Geography 12/4/23
Alfred Wegner
Theory of Continental Drift (1915) - Continents at one time were all together as a super continent called Pangea (All Earth).
Tectonic Plates: Massive slab of solid rock made up of Earth's lithosphere (crust and upper mantle). Also called lithospheric plate.
Found the rocks in the center of Atlantic ocean were much younger than the rocks on the edge of the Atlantic ocean.
Rift: Plates pulling away from each other.
Mid Atlantic Ridge
Plate Boundary: Boundaries between plates Rift: Plates pulling away from each other Crack forms and exposes molten Forms mid ocean ridge (under water mountain range)
Iceland: Iceland is facing a potential volcanic eruption that could happen with just 30 minutes warning. The country sits on the Mid-Atlantic Ridge, where two tectonic plates are moving apart. This causes magma to rise to the surface and create pressure.
Plate Collision: Plates colliding with one another.
Constant collisions
Mount Everest
Subduction Zone: One plate diving under another. Another example of plates coming together, but different from plate collision because one plate is significantly weaker than the other.
Constant collision
Pacific Ring of Fire: The coastlines of the Pacific Ocean characterized by numerous volcanoes and earthquake activity.
Numerous volcanoes and earthquakes found in this area.
Geography 12/6/23
Mount Aconcagua
Mexican Volcano
Japan's Mount Fuji
Mount Pinatubo 1991 - Largest volcanic eruption of the 20th century
Plate Boundaries continued
Transform Fault - Plates moving side to sid
San Andreas Fault - Most researched transform fault in the world, because it passes through heavily populated areas.
Earthquakes are common along active faults
Earthquake - Ground shaking energy released by sudden movement of the Earth's crust. Usually the result of displacement along a fault.
*** Seismology - The science that studies earthquakes *** Seismograph - Instrument used to record earthquakes Seismogram - A tracing of earthquake's energy
Portable Seismograph
Earthquake Terms
Focus - The underground center of motion Epicenter - The point on the Earths surface directly above the focus
Charles Richter
Richter Scale - Rating Earthquake intensity.
Open ended logarithmic scale
As you go higher up on scale, intensity of earthquakes become much higher.
Earthquake Hazards
Building Collapse
Fire
Landslides
Tsunami
Soil Liquefaction - Fill and soft sediments become liquefied due to ground shaking.
Anchorage Alaska 1964 - Highest rated earthquake on Richter Scale (9.4).
Marina District 1989 - Building collapsed, natural gas pipe ruptured.
Tsunami - Seismic sea wave generated by an earthquake under the sea floor.
Indian Ocean Tsunami - December 2004 Tohoku Earthquake - March 2011
California's Subsidiary Faults
Loma Prieta Earthquake - October 1989
New Madrid, Missouri
3 Earthquakes December 1811 - February 1812
Predicting Earthquakes - No success
Earthquakes in Maryland
Most 2 Magnitude or less
Largest Earthquake - 3.8 Phoenix, MD 1939
Many felt in Maryland occur elsewhere
Great Baltimore Fire - 1904
Downtown destroyed
Geography 12/8/23
Landform Producing Forces
Tectonic Forces - Forces that build up landforms.
Endogenetic Forces - Forces that originate from within the Earth.
Tectonic Forces
A. Diastrophism (Solid state, movement of solid rock)
1. Folding (Bending of rock)
2. Faulting (Breaking of rock)
B. Vulcanism (Molten state; 2000 degrees or more)
1. Intrusive (Movement of magma beneath the surface)
2. Extrusive (Movement of lava and other products above the surface)
Black Hills - The Black Hills is an isolated mountain range rising from the Great Plains of North America in western South Dakota and extending into Wyoming, United States.
Mount Rushmore is here; sculpture chose this area because of the granite there.
Volcano Cutaway
Production of Eruptions
Strato volcanoes
Pyroclastic flow - A pyroclastic flow is a fast-moving mixture of hot gas and volcanic matter, such as ash and rock fragments, that travels down the slopes of a volcano during an eruption. These flows are extremely dangerous and can reach high speeds (100+ MPH).
In the conterminous United States (the 48 contiguous states), you can find volcanoes primarily in the Cascade Range in the Pacific Northwest. The Cascade Range extends from northern California through Oregon and Washington to southern British Columbia in Canada. Notable volcanoes in this region include Mount St. Helens, Mount Hood, Mount Rainier, and Mount Shasta.
Geomorphology - The study of landforms.
Forces which wear down
Exogenetic forces (From outside the Earth)
Degradation - The wearing down of rock material
1. Weathering (Breaking down)
a. Chemical
b. Physical
Chemical Weathering occurs primarily through acid precipitation.
Pollutants mix with the water in the air to produce acid, which destroys rock when it comes in contact
Frost wedging
Plant Roots can do the same thing
Rodents also do their part
Mountain Bikes also contribute to physical weathering
2. Erosion (Removal)
a. Water
b. Wind
c. Ice
Stream Erosion
Volume plays a big role. The greater the volume of the water, the more sediments are picked up.
Wind Erosion
Only found in dry environments
Dunes
Mountain Glaciers
A glacier is a river of ice; Mountain glaciers start off in higher elevations with heavy snow, which compacts into ice and over time works it way down the slope, picking up on rocks and boulders, grinding against the ground, being transported down the slope by the ice and eventually to the ocean.
Calving - The process by which large chunks of ice break off from the edge of a glacier and fall into the water, forming icebergs.
Most of the ice from a glacier is under the water because of the density of the ice.
North American Ice Sheet
Greenland
All of the ice in Greenland will probably be gone in the next century or two
b. Aggradation (Depositing) (Aggradational Landform examples below)
1. Beaches (Example: Ocean City)
2. Deltas - Formed where a major river enter into a larger body of water; Deltas feature very fertile soil, usually flat.
3. Dunes
William Morris Davis - By training, he was a geomorphologist. His specialty was streams and rivers.
Geomorphic Cycle - Goes through stages, similar to human conditions (minus the rejuvenation stage).
Youthful Landform - MT. Everest because it is growing, getting taller
Mature Landform - The Rockies because they are not growing
Old Age Landform - Appalachian because it is slowly deteriorating. Over time, it will completely disappear. (No tectonic activity)
Rejuvenation - Plate collision can cause this
