Internal Processes
Internal processes are responsible for the gross shape of lithospheric landscape.

The Internal Processes
 Rigid Earth theory
 Plate Tectonics
 Vulcanism
 Folding and Faulting
 Earthquakes
Rigid earth

Continental crust
Oceanic and continental crusts
Asthenosphere
Isostatic Depression
Importance of Isostatic processes
Isostasy


Continental drifts
Pangaea
 The massive supercontinent that Alfred Wegener postulated to have existed about 250 million years ago.

Evidence of continental drifts
 Close affinities of geologic features on both sides of Atlantic Ocean.
 Continental margins of subequatorial portions of Africa and South America fit together.

Plate Tectonic
 It is a theory of geology that has been developed to explain the observed evidence for large scale motions of the Earth's lithosphere.
Evidence of plate tectonic

1. Sea floor spreading
 Paleomagnetism
 Plate boundary
2. Subduction
 Convection and plate tectonics
Sea floor spreading
 Seafloor spreading—theory proposing that oceanic ridges are formed by currents of deep-seated magma rising up from the mantle (often during volcanic eruptions), creating new crust on the ridges (the newest crust formed on the planet).

Theory of seafloor spreading –
two sets of evidence
Paleomagnetism
Core sampling
Earth magnetic field
Paleomagnetism
 Paleomagnetism is the study of the record of the Earth's magnetic field preserved in various magnetic minerals through time.
 ----demonstrated that the Earth's magnetic field varies substantially in both orientation and intensity through time.

Sea floor spreading
Earth’s magnetic field

http://www.youtube.com/watch?v=lPLjnqS8UeY&feature=related

http://www.youtube.com/watch?v=wxQsLLOYC7Q&feature=related

Core sampling
 Sediment age and thickness increase with increasing distance from the ridges, indicating that sediments farthest from ridges are oldest.
Subduction
 Process proposed to explain trenches, making them the site where older crust descends into the interior of Earth, where it is presumably melted and recycled into the convective cycle that operates in Earth.
Subduction zone
 A subduction zone is an area on Earth where two tectonic plates meet and move towards one another, with one sliding underneath the other and moving down into the mantle, at rates typically measured in centimeters per year.
Subduction zone

Plate boundary
 Oceans have a continuous system of large ridges located some distance from continents, often midocean.
 Also, deep trenches occur at many places in the ocean floors, often around margins of ocean basins.
 Most of the action of plate tectonics takes place along these boundaries.

Only three types of contacts between plates are possible
 Divergent
 Convergent
 Laterial slide
Divergent Boundary
 Divergent boundary—type of plate association in which two plates are moving away from each other because of magma welling up from asthenosphere
 Usually represented by midocean ridges
 Divergence boundaries are said to be contructive because it adds materials to the crustal surface at such locations
 Most common in oceanic ridge, but also occurs within a continent, as in East African Rift Valley.
 The red sea is also an outcome of the spreading taking place within a continent

Convergent boundary
 Type of plate association in which two plates are colliding.
 Sometimes called destructive because they result in removal or compression of the surface crust
 Normal result is one plate being subducted, but showing crumpling at the edges where they meet (often resulting in massive and spectacular landforms).
Types
 Oceanic–continental convergence
 Oceanic–oceanic convergence
 Continental–continental convergence
Oceanic-continental convergence
 Denser oceanic lithosphere underrides continental lithosphere when the two collide
 The subducting slabs pulls on the rest of the plate. Here denser oceanic plate is subducted, and oceanic trench and coastal mountains are usually created

Examples
 Andes
 The Cascades in northwestern North America
 Accompanied by earthquakes, and volcanoes develop
Oceanic–oceanic convergence
 creates oceanic trench and volcanoes on ocean floor, which initiate volcanic island arc (e.g., Aleutians and Japan).
Continental-continental convergence
 Here no subduction occurs, so huge mountain ranges are built up (e.g., Alps and Himalayas).
 Volcanoes are rare, but shallow-focus earthquakes common.

http://www.youtube.com/watch?v=jRfEGvp6wDU

http://www.youtube.com/watch?=Oa4vhwVP_JA&feature=PlayList&p=DDCC256E4FA7EA3F&index=0&playnext=1

Introduction to Landform study

Introduction to landform study
Inside the earth
http://www.youtube.com/watch?v=3xLiOFjemWQ&feature=related

Unknown interior
Humans have not penetrated more than one-thousandth of Earth radius.
Inferential knowledge of earth interior through monitoring shock waves transmitted through Earth from earthquakes or from human-made explosions.
Deduced that earth has a heavy inner core surrounded by three concentric layers of various composition and density.The deepest existing mine is only 3.8 kilometers.The deepest drill is only 12kilometers

The Unknown Interior
Crust
Mantle
Outer Core
Inner Core

Crust
Crust is the outermost solid layer of Earth,consist of broad mixture of rock types.
On average, crust three times as thick under continents as under ocean.
5-9 km deep beneath the ocean floor and
25-60 km beneath the continents

Moho
Mohorovičić discontinuity (Moho)—the boundary between Earth’s crust and mantle.

Mantle
that portion of Earth beneath the crust and surrounding the outer core,
depth of 2,900 kilometers (1,800 miles).
Largest volume of all four shells.
Scientists believe three zones within mantle:
lithosphere,
asthenosphere,
mesosphere
Mantle- lithosphere
Lithosphere—the uppermost zone of mantle and the crust together.
Sometimes used as a general term for the entire solid Earth.)

Asthenosphere
Asthenosphere—plastic layer of the upper mantle that underlies the lithosphere.
Its rock is very hot and therefore weak and easily deformed.

Mantle-mesosphere
Mesosphere—the rigid part of the deep mantle.
Outer core
The (molten) liquid shell beneath the mantle that encloses Earth’s inner core.
Inner core
The supposedly solid, dense, innermost portion of Earth,
Consist largely of iron/nickel or iron/silicate.

Composition of the Earth
Minerals
Igneous Rocks
Sedimentary Rocks
Metamorphic Rocks
Rock Classes
Minerals
Minerals
A naturally formed inorganic solid substance that has an unvarying chemical composition and characteristic crystal structure.Over 4400 minerals have been identified with new types identified almost every yearOnly a few are important constituents of the rocks of earth’s crust
Ex. Silicates, oxides, sulfides, halides.
Rocks
solid material composed of aggregated mineral particles (in lithosphere).
Less than 20 minerals account for more than 95% of the composition of all continental and oceanic crustal rocks
Where are rocks found????
Outcrops
Outcrop is a geological term referring to the appearance of bedrock or superficial deposits exposed at the surface of the Earth
Bedrock
Solid rocks buried beneath the earth surface
Regolith
Broken rocks that overlay bedrock
Magma and Lava
molten rocks in Earth’s interior.Quantity unknown.

Lava
Lava refers to molten rocks when it flows out on, or squeezed up onto, the surface

Classes of rocks
There are three major rock classes
Igneous rocks
Sedimentary
Metamorphic

Types of rocks
http://www.youtube.com/watch?v=wZwit_VHdrE

Igneous rocks
rock formed by solidification of molten magma.
Many kinds, but principal shared trait is crystalline structure.

Types of Igneous rocks
Plutonic (intrusive) rock
Volcanic ( Extrusive) Rocks
Igneous Rocks
Extrusive
molten rock ejected onto Earth’s surface, solidifying quickly in the open air.
Extrusive Igneous
Intrusive
rocks that cool and solidify beneath Earth’s surface (may be pushed up to surface or exposed through erosion).
Granite is most common and well known
Intrusive Igneous
Sedimentary Rocks
Sediment—small particles of rock debris or organic material deposited by water, wind, or ice.
rock formed of sediment that is consolidated by the combination of pressure and cementation.
During sedimentation, materials sorted roughly by size (the finer particles carried farther than heavier particles).
Strata
Strata (plural; stratum, singular)—distinct layers of sediment
Results in parallel structure (stratification), with layers varying in thickness and composition.
Categories of Sedimentary rocks
Categorized by how they formed:
mechanically,
chemically,
organically.

Mechanically accumulated..
Mechanically accumulated: fragments of preexisting rocks.
For example, shale and sandstone.

Shale
is a fine-grained sedimentary rock that is formed by the compression of muds
chemically accumulated..
precipitation of soluble materials or chemical reactions.
For example, calcium carbonate and limestone.

organically accumulated
remains of dead plants or animals.
For example, coal and limestone.

Metamorphic rocks
rock that was originally something else (igneous or sedimentary) but has been drastically changed by massive forces of heat and/or pressure working on it from within Earth.
Metamorphic Rocks
Process recrystallizes and rearranges mineral components.
Some predictability, such as limestone metamorphized becomes marble.
Sometimes metamorphosis so great, can’t determine nature of original rock.
Most common are schist and gneiss.
schist and gneiss
Rock cycle
describes the dynamic transitions through geologic time among the three main rock types: sedimentary, metamorphic, and igneous.
The Rock Cycle
Distribution of Rock Classes
Critical Concepts
Basic Terms
Topography
Geomorphology
Landform
Relief
Uniformitarianism
“The present is the key to the past”
Geologic Time

ATMOSPHERE

INTRODUCTION TO THE ATMOSPHERE

The Atmosphere
The atmosphere is a mixture of different gases, particles and aerosols collectively known as air which envelops the Earth. More than 98% of atmosphere lies within 26 kilometers [16 miles] of Earth’s surface).

Composition of the atmosphere
Chemical composition of the atmosphere is simple and uniform at elevation below 80km (50miles)
Gases
Particulates
Permanent Gases

The Gases
Air—synonymous with atmosphere, is a mixture of gases, mainly nitrogen and oxygen.
Basic composition of air:
Nitrogen—78%
Oxygen—21%
Argon—nearly 1%

Nitrogen
Added to the air by:
The decay and burning of organic matter;
volcanic eruptions ;
Chemical breakdown of certain rocks
Removed from the air:
Washed away in rain or snow
Oxygen
Added to the atmosphere by plants and vegetation

Variable Gases
Water vapor
It is the gas phase of water. Can be produced from the evaporation of liquid water or from the sublimation of ice.Water vapor is variable in location but not variable in time: Abundance in air overlying warm moist surface, Source of clouds and precipitation, has significant effect on weather and climate…..
------how?

Carbon dioxide
Carbon dioxide is produced by all animals, plants, fungi and microorganisms during respiration and is used by plants during photosynthesis to make sugars which may either be consumed again in respiration or used as the raw material for plant growth.

Added to atmosphere by burning of fossil fuel. Helps to heat lower atmosphere by absorbing infrared radiation.
Evenly distributed at lower atmosphere
Increased concentration due to increased burning of fossil fuel

Ozone
Ozone is a relatively unstable molecule (03) composed of 3 oxygen atoms . Ground-level ozone is an air pollutant with harmful effects on the respiratory systems of animals. Ozone in the upper atmosphere filters potentially damaging ultraviolet light from reaching the Earth's surface.

Upper and ground ozone layers

Health effect of ground level ozone
Eye irritation; headaches; coughing; impaired lung function; and eye, nose, and throat irritation.
Asthmatics and children are most at risk. Ground-level ozone can also damage trees, plants, and reduce visibility.

What causes ground level ozone
It is also a product of reactions between chemicals that are produced by burning coal, gasoline, other fuels, and the chemicals found in paints and hair sprays.

How can we reduce my contribution to ground-level ozone?
Avoid idling your motor vehicle excessively.
Conserve energy and recycle.
Keep your vehicle well tuned.
Limit driving; carpool, walk, ride a bicycle, and combine trips

Atmospheric variable gases on weather and climate
Only water vapor and carbon dioxide have a significant effect on weather and climate.
Water vapor determines the humidity of the atmosphere. It is the source of all clouds and precipitation, and is intimately involved in the storage, movement, and release of heat energy.
Carbon dioxide absorb infrared radiation, keeping the lower atmosphere warm.

Atmospheric Particulates
Solid and liquid particles found in the atmosphere; can be both visible to eye and invisible; come from both natural and human-made sources.
Impact on weather and climate
They are hygroscopic (they absorb water), and water vapor collects around them, which contributes to cloud formation;
They can either absorb or reflect sunlight, thus decreasing the amount of solar energy that reaches Earth’s surface.

Vertical Structure of the atmosphere
Troposphere
From the earth's surface to 11-12 km above, temperature decreases with height.
troposhere. The rate of change of air temperature with height is called the "lapse rate".
In the troposphere, the lapse rate is generally about 6.5 deg C per kilometer increase in altitude.

tropopause
The boundary between the troposphere, and the stratosphere
The height of the tropopause from the ground ranges from 8 km in high latitudes, to 18 km above the equator. The tropopause is a boundary layer defined by a sudden change in lapse rate.
stratosphere
The stratosphere is marked by a temperature inversion from about 11-12 km to 50 km above sea level. stratosphere is a region of little mixing
Many of the commercial jets fly in or near this layer

Why does temperature increase with altitude in the stratosphere?
Because the ozone (O3) layer mostly resides at this level in the atmosphere.
Ozone absorbs UV radiation from the sun which, in turn, increases the motion of the ozone molecules. The ozone molecules then collide with other molecules in the air, increasing its temperature.

Mesosphere
The mesosphere resides from about 50 km to 80-90 km above the earth's surface.
This area is where meteoroids burn up and leave a streak in the night sky
Low atmospheric pressure. There is not a layer of ozone to cause heating, so temperatures are colder as height increases.

Thermosphere
The thermosphere lies above about 90 km. The highest recognized thermal layer in the atmosphere, here temperature increases continually with height.The Theromsphere includes in both the Ionosphere and the Exosphere.

ionosphere
The Ionosphere reflects radio waves back to the earth. The ions and dust particles also create a fabulous light show known as the aurora borealis sometimes called the northern lights

Exospherre
The Exosphere is where we often term as space, it's that area that holds the satellites that allow us to communicate by way of TV and other means

Atmospheric pressure
Atmospheric pressure is basically the weight of overlying air. Thus air pressure is normally highest at sea level and rapidly decreases with altitude.

Atmospheric Moisture
Most atmospheric moisture occurs in three physical states
Solid (snow, hail, sleet, ice)
Liquid (rain, droplet)
Gas (water vapor)
The Impact of Atmospheric Moisture on the Landscape
Atmospheric moisture influences landscape both in short term and long term.
Short term; flooding, snow and ice;
Long term, with precipitation integral to weathering and erosion, critical to vegetation.
Nature of water
Occupies 70% of the surface of the planet
Pure water has no color
No taste
No smell
Turns to solid at 0°C (32°F)
Boils at sea level at 100°C (212°F)

Water Molecules
Two atoms of hydrogen and one atom of oxygen, bond to form water molecule
The hydrogen side of the water molecule has a positive charge
The oxygen side has negative charge


Properties of water
Water contracts only until it reaches 4°C (39°F) and expands to its freezing point of 0°C (32°F)
Because water expands as it approaches freezing, ice is less dense than liquid water
All lakes freeze from the top down
Water is adhesive
Water has capillarity effect
Water is a universal solvent
Phase change of water
Transitions between solid, liquid, and gaseous phases typically involve large amounts of energy.
The energies required to accomplish the phase changes is called the latent heat
There are three phases:
Evaporation
Condensation
Sublimation
Evaporation- the conversion of liquid water to its gaseous form ( water vapor)
Condensation- the conversion of water vapor to liquid water
sublimation- process whereby a substance converts either from gaseous state directly to solid state or solid face directly to gaseous state without even passing through the liquid state

Water vapor
Invisible gas that mixes freely with other gases of the atmosphere
It is restricted to the lower troposphere (1.5km) of earth’s surface
It is colorless
Odorless
Tasteless
How is water vapor added to the air?
When the rate of evaporation exceeds condensation-
Thus when there is net evaporation
This depend on three factors
Temperature( of both air and water)
Amount of water vapor already in the air
Motion of air

Temperature
Warm air and high water temperature promote evaporation
Molecules become more agitated when the air and water temperature increases.
The higher the temperature the higher the maximum vapor pressure
Vapor pressure
Vapor pressure is the pressure exerted by water vapor in the air
1. At any given temperature, there is a maximum vapor pressure that water vapor molecules can exert
Saturated air
The amount of water vapor that air can contain is limited, and when that limit is reached air is said to be saturated.The warmer the air, the more water vapor it can hold before becoming saturated.

Amount of water vapor already in the air
If the air overlying water surface is almost saturated with water vapor, the rate of evaporation is the same as the rate of condensation- there is little evaporation
Still verse Moving air
If the air is in motion,
windiness and/or turbulence helps promote evaporation by removing saturated air
a) Moving air disperses vapor molecules and thus makes air above water surface less saturated, so rate of evaporation can increase.
Evapotranspiration
Evapotranspiration—the sum of evaporation and plant transpiration from the earth's land surface to atmosphere
Evapotranspiration
Evapotranspiration occurs through two ways:
Transpiration—the process by which plant leaves give up their moisture to the atmosphere;
Evaporation from soil and plants
Potential evapotranspiration
This is the amount of evapotranspiration that would occur if the ground at the location in question were sopping wet all the time
Potential evapotranspiration rate and actual rate of precipitation play a key role in determining a region’s groundwater supply (or lack of it).
Hydrologic cycle
It is the continuous interchange of moisture between earth and the atmosphere
Essentials
Evaporation-Liquid water ( primarily from ocean) evaporates into the air
Condensation-changes into liquid
Precipitation-fall as rain, snow etc

Measures of Humidity
Humidity—the amount of water vapor in the air.
It can be measured and expressed in a number of ways
Absolute Humidity
Relative humidity
Specific humidity
These are different ways to express the water content in a parcel of air.
Absolute humidity
It is the amount of water vapor in a given volume of air
Expressed as the weight of water vapor in a given volume of air, usually as grams of water per cubic meter of air.
Absolute humidity is limited according to temperature.
a) The colder the air, the less vapor it can hold.
Concept of Absolute Humidity
If all the water in one cubic meter of air were condensed into a container, the container could be weighed to determine absolute humidity.
The amount of vapor in that cube of air is the absolute humidity of that cubic meter of air.
Specific Humidity
Specific humidity The mass of water vapor per unit mass of air, including the water vapor
(usually expressed as grams of water vapor per kilogram of air).
Specific humidity does not vary as the temperature or pressure of a body of air changes, as long as moisture is not added to or taken away from it
This stability of the specific humidity makes it useful as an identifying property of a moving air mass
Relative Humidity
Relative humidity is an expression of the amount of water vapor in the air in comparison with the total amount that could be there if the air were saturated.
This is a ratio that is expressed as a percentage.
Relative humidity describes how close the air is to saturation with water vapor
It changes if either the water vapor content or the water vapor capacity of the air changes
Capacity is the maximum amount of water vapor that can be in the air at a given temperature.
It can be determined through the use of a psychrometer
Relative Humidity and Temperature
Dew Point
The temperature at which saturation is reached is called the dew point temperature

Condensation
Process whereby water vapor is converted to liquid water
Essential conditions
The air must be saturated
There must be condensation nuclei or hydroscopic particles
For condensation to take place, air must be saturated.
Condensation cannot occur, however, even if the air is saturated, if there is not a surface on which it can take place.
Air becomes supersaturated if surface is not available
In upper atmosphere, surfaces are available through hygroscopic particles or condensation nuclei
Condensation Nuclei
They are airborne particles upon which water vapor can condense to produce cloud droplets. Examples:
They are tiny microscopic therefore invisible to the eye (about 0.2 – 10.0 microns)
They are particles light enough to remain suspended in the air.
They are formed from a variety of sources including dust, pollen, smoke, salt from ocean
Type of condensation nuclei
There are two broad categories of condensation nuclei:
Hygroscopic
Hydrophobic.

Hygroscopic nuclei
Hygroscopic nuclei are “water seeking” nuclei.
Water vapor condenses on hygroscopic surfaces readily even when the relative humidity is considerably lower than 100 percent.
Example Salt
Hydrophobic nuclei
Hydrophobic nuclei are water repelling. Water vapor will condense on hydrophobic surfaces only at relative humidity’s greater than 100 percent, and even then with great difficulty.
Examples are oil, and gasoline.

Adiabatic process
It is a process which occurs with no exchange of heat between a system and its environment.
When air rises, it pressure decreases, and so it expands and cools adiabatically
Adiabatic process
Large masses of air can be cooled to the dew point ONLY by expanding as they rise.
Because of this limitation, adiabatic cooling is the only prominent mechanism for development of clouds and production of rain
Dry adiabatic rate
The rate at which a parcel of unsaturated air cools as it rises;
This rate is relatively steady (6.5°F per 1000 feet) (10°C/km).
Air is not necessarily “dry,” just not saturated.
Descending air warms, and it does so at the dry adiabatic lapse rate.
Lifting condensation level
The altitude at which rising air cools sufficiently to reach 100% relative humidity at the dew point temperature, and condensation begins.
Saturated Adiabatic Rate
The diminished rate of cooling, which occurs when air rises above the lifting condensation level
It depends on temperature and pressure, but averages about
3.3°F per 1000 feet
(6°C/1000 meters)
Clouds
Clouds are collections of minute droplets of water or tiny crystals of ice
Not all clouds precipitate, but all precipitation comes from clouds
At any given time, about 50% of Earth is covered by clouds.

Formation of clouds
Ascending air expands, cools adiabatically and, if sufficiently moist, some of the water vapor condenses to form cloud droplets
Importance of clouds
Clouds play an important role in the global energy budget.
Receive insolation from above and terrestrial radiation from below.
a) They absorb, reflect, scatter, or reradiate this energy, and so influence radiant energy
Classification of clouds
Clouds are classified on the basis of two factors:
Forms
Altitude
Forms of clouds
There are three forms of clouds
Cirriform clouds
Cumuliform clouds
Stratiform clouds

Cirriform clouds
A cloud that is thin, wispy, and composed of ice crystals rather than water particles;
It is found at high elevations
Cumuliform clouds
A cloud that is massive and rounded,
With a flat base and limited horizontal extent, but often billowing upward to great heights.
Stratiform clouds
Clouds that appear as grayish sheets or layers that cover most or all of the sky, rarely being broken into individual cloud units.
Sub classification of clouds
These 3 cloud forms: Stratiform, cumuliform, cirriform are sub classified into 10 types based on shape
Three of these 10 are purely one form, while the other 7 are combinations of these three
Three pure forms of clouds
Cirrus cloud
Cumulus cloud
Stratus cloud—low clouds, usually below 6500 feet (2 km), which sometimes occur as individual clouds but more often appear as a general overcast.
Cirrus cloud—high cirriform clouds of feathery appearance
Cumulus cloud
Cumulus cloud—puffy white cloud that forms from rising columns of air.
Stratus cloud
Stratus cloud—low clouds, usually below 6500 feet (2 km),
Sometimes occur as individual clouds but more often appear as a general overcast.
Clouds based on Altitude
The ten cloud types are divided on into four families on the basis of altitude
High clouds-
Middle clouds-
Low clouds-
Vertical clouds
Examples
High clouds- above 20,000 feet:
cirrus, cirrocumulus, cirrostratus
Middle clouds-6500-20,000 feet
altocumulus, altostratus
Low clouds- below 6500: stratus, stratus cumulus, and nimbostratus
Vertical clouds-
cumulus, cumulonimbus (storm clouds)

Fog
There are no physical difference between clouds and fog
But there are differences in how each formed
Formation of fog
Fog is formed when moist air is cooled, not by expansion but by contact with a colder surface.
Types of fogs
Radiation fog
Advection fog,
Precipitation or frontal fog),
Upslope fog

Radiative fog
This type of fog forms at night under clear skies with calm winds when heat absorbed by the earth’s surface during the day is radiated into space
Advection fog
This develops when warm, moist air moves horizontally over cold surface, such as snow-covered ground or cold ocean current
Ex.Sea fogs are always advection fogs
Upslope Fog
Upslope fog forms when light winds push moist air up a hillside or mountainside to a level where the air becomes saturated and condensation occurs
Evaporation or Mixing Fog
This type of fog forms when sufficient water vapor is added to the air by evaporation and the moist air mixes with cooler, relatively drier air.
Precipitation
Precipitation comes only from clouds that have “nimb“ in their name; specifically, nimbostratus or cumulonimbus. When cloud particles become too heavy to remain suspended in the air, they fall to the earth as precipitation
Precipitation comes from clouds but not all clouds precipitate
Condensation alone is insufficient to produce rain drops
Processes
Two mechanisms are believed to be principally responsible for producing precipitation
Ice-crystal formation
Collision and coalescence of water droplets
Collision/coalescence
Most responsible for precipitation in the tropics and produces much precipitation in the middle latitudes
Collision/Coalescence
Ice-crystal formation
It is believed to account for the majority of precipitation outside of tropical regions.
Ice crystals and supercooled water droplets in cloud are in direct competition for water vapor not yet condensed.
Forms of Precipitation
Rain—the most common and widespread form of precipitation, consisting of drops of liquid water.
Snow-solid precipitation in the form of ice crystals, small pellets, or flakes, which is formed by the direct conversion of water vapor to ice
Forms of precipitation
Sleet—small raindrops that freeze during decent, reaching ground as small pellets of ice.
Glaze—rain that turns to ice the instant it collides with a solid object
Hail is a large frozen raindrop produced by intense thunderstorms.
hail
Atmospheric Lifting and Precipitation
There are four types of atmospheric lifting
Convective lifting
Orographic lifting
Frontal lifting
Convergent lifting
Convectional precipitation
Showery precipitation with large raindrops falling fast and hard
This occurs when unequal heating of different air surface areas warms one parcel of air and not the air around it.

Orographic precipitation
This is caused when topographic barriers force air to ascend upslope;
Orographic only occurs if the ascending air is cooled to the dew point.

Frontal precipitation
This occurs when air is cooled to the dew point after unlike air masses meet, creating a zone of discontinuity (front) that forces the warmer air to rise over the cooler air (frontal lifting).
Frontal Lifting
Convergent lifting
Occurs when air parcels converge and the crowding forces uplift, which enhances instability.
This precipitation is particularly characteristic of low latitudes.
This is the least common form of lifting
End

atmospheric pressure part one

Atmospheric Pressure and Wind
Pressure and wind are the major elements of weather and climate
What is atmospheric pressure?
The force exerted by gas molecules in the atmosphere.

Nature of atmospheric pressure
Affects Earth’s surface as well as any other body on Earth.
Omnidirectional force—exerted equally in all directions.
At sea level atmospheric pressure is about 14.7pounds per square inch
Force drops with increasing altitude because actual number of gas molecules also drops

Impact of pressure and wind on the landscape
Humans not as sensitive to air pressure as they are to other three climate elements (heat, air movement, and humidity).

Air pressure acts and responds to other three climate elements, but most intimately with wind.

Air movement
Spatial variations in pressure create air movements
Pressure,
Density,
Temperature
Variations in any one—pressure, density, and temperature of atmosphere—affect the other two. Relationship is very complex, so difficult to make exact predictions of how change in one changes the others.

How pressure varies with density
Density is how heavy something is for its size
Something that's very heavy and small has a high density.

Measurement of density
Density is Mass divided by Volume.
It's usually measured in kilograms per cubic meter.
To work out the density of something, divide mass (how much it "weighs”), by volume (how much space it takes up

Density and pressure
Density of gas changes easily because gas expands as far as the environmental pressure will allow.The density of a gas is proportional to the pressure on it
The denser the gas, the greater the pressure it exerts.

Mapping pressure with Isobars
Barometer—instrument for measuring atmospheric pressure.
Isobars are lines of constant pressure
Mapping with Isobars
If the number now is between 0 and 55.9, add a leading 10, i.e. 1012.6If the number is between 56.0 and 99.9, add a leading 9.

High and low pressure areas
High” and “low” pressures are relative conditions, with the distinction depending on the pressure of the adjoining areas
.

High pressure area
Winds around a High blow in a clockwise direction away from the center. (“The clock is high.”) Highs usually have fair weather.

Low pressure
Winds around a Low blow in a counter-clockwise and inward. (“The counter is low.”) Low pressure systems often have stormy or unsettled weather.

Pressure gradient
The horizontal rate of pressure change, representing the “steepness” of the pressure slope; has a direct effect on the speed of wind.

The Nature of Wind
Wind—horizontal movements of air
Vertical motions of wind
Updrafts and downdrafts—small-scale vertical motions.
Ascents and subsidences—large-scale vertical motions

Directions of movement
Depends on the interaction of three factors:
pressure gradient
friction
Coriolis effect (Earth’s rotation)

Pressure Gradient
Coriolis Effect
The deflection of free moving objects to the right in the Northern Hemisphere.
To the left in the Southern Hemisphere, in response to the rotation of Earth.

Friction
Geostrophic wind
A wind that moves parallel to the isobars as a result of the balance between the pressure gradient force and the Coriolis effect.

Cyclones and Anticyclones
Cyclone—low-pressure cell.
Anticyclone—high-pressure cell.

Cyclones and Anticyclones
TO BE CONTINUED

Atmospheric pressure part 2

Cyclones and Anticyclones
Cyclone—low-pressure cell.
Anticyclone—high-pressure cell.

Cyclones and Anticyclones
Circulation patterns
Eight circulation patterns are possible because of the interaction of the pressure gradient, Coriolis effect, and friction.
Four involve anticyclones.
Four involve cyclones

Circulation Patterns
Circulation Patterns
Wind Speed
Is determined by pressure gradient.
The steeper its slope, the faster the wind.
Most persistent winds are usually in coastal areas or high mountains
Wind Speed
Vertical Variations in Pressure and Wind
Atmospheric pressure usually decreases rapidly with height.
Wind speed usually increases with height; winds tend to move faster above friction layer.


General Circulationof the Atmosphere
Rotation of Earth and its variable surfaces is key in creating a complex circulation pattern for atmosphere
Only the tropical regions have a complete vertical cell.

General Circulationof the Atmosphere
Hadley Cells
Components of General Circulation
Jet Streams
HADLEY CELL
Assume that
earth is uniformly covered with water
sun is directly over equator
no rotation
you will end up with a single-cell pattern called Hadley cell…

Hadley cells
warm air rises at the equator, cold air sinks at the poles
Hadley cells
This is a complete vertical circulation cells in which warm air rises to elevations of about 50,000 feet (15 km), where it cools and moves poleward, then subsides.
The cell’s air rises at the equator and descends at about 30° of latitude (either north or south, depending on cell).

Hadley Cells
Hadley cells
The general circulation of the atmosphere has seven surface component
Subtropical latitude
Subtropical latitudes serve as the “source’ of the major surface winds of the planet.

Subtropical latitude
They are latitudes between 30 and 35 degrees both north and south.
under a ridge of high pressure called the Subtropical ridge
It is an area which receives little precipitation and has variable winds mixed with calm.
Subtropical latitude
Components of General Circulation
Subtropical Highs
Trade Winds
Intertropical Convergence Zone
The Westerlies
Polar Highs
Polar Easterlies
Subpolar Lows
Subtropical Highs
Subtropical highs— (STHs) large semi permanent high-pressure (anticyclone) cells centered at about 30° latitude over the oceans;
Have average diameters of 3,200 kilometers (2,000 miles) and are usually elongated east–west.
Develop from the descending air of the Hadley cells.

Subtropical Highs
Horse latitudes
Areas in the subtropical highs characterized by warm, tropical sunshine and an absence of wind;
This is created because weather within an STH is nearly always clear, warm, and calm.
Where?
STHs also coincide with most of the world’s major deserts.

Landforms in the area
The consistently warm, dry conditions of the horse latitudes also contribute to the existence of temperate deserts
Trade winds
Winds are named for the direction they blow from
Trade winds’ origin depends on which hemisphere they are in
Trade winds
the major wind system of the tropics, issuing from the equatorward sides of the subtropical highs and diverging toward the west and toward the equator.
Trade winds
Most reliable of all winds, being extremely consistent in both direction and speed.
Northern and Southern hemisphere trade winds
In Northern Hemisphere, trade winds originate in northeast, so are sometimes called northeast trades.
In Southern Hemisphere, originate in southeast, so are sometimes called southeast trades.
Characteristics of trade winds
They do not release moisture unless forced by a topographic barrier or pressure disturbance.
Windward slopes in trade winds, as in Hawaii, are some of the wettest places on Earth
Intertropical convergence zone
is a belt of low pressure surrounding the Earth at the equator.
Also called equatorial front, intertropical front, and doldrums
ITCZ
It is formed by the vertical ascent of warm, moist air from the latitudes above and below the equator
regions in the intertropical convergence zone receive precipitation over 200 days in a year.
Doldrum
The doldrums is a colloquial expression derived from historical maritime usage for those parts of the Atlantic Ocean and the Pacific Ocean affected by the Intertropical Convergence Zone,
a low-pressure area around the equator where the prevailing winds are calm
The Westerlies
are the prevailing winds in the middle latitudes between 30 and 60 degrees latitude, blowing from the high pressure area in the horse latitudes towards the poles.
Westerlies
Jet streams
Two cores of high-speed winds at high altitudes in the westerlies:
Polar front jet stream
Subtropical front jet stream
Jet Streams
Polar Highs
A high-pressure cell situated over either polar region.
Because it forms over an extensive, high-elevation, very cold continent, Antarctic high differs greatly from Arctic high.
Polar Easterlies
a global wind system that occupies most of the area between the polar highs and about 60° of latitude.
The winds move generally from east to west and are typically cold and dry.
Monsoon
monsoon
a seasonal reversal of winds; a general onshore movement in summer and a general offshore flow in winter, with a very distinctive seasonal precipitation regime.
South Asian Monsoon
MonsoonsMonsoon Areas of the World
Localized wind systems
Sea and Land Breeze
Land breeze
Land breeze—local wind blowing from land to water, usually at night (and normally considerably weaker flow than that of sea breeze).
Sea breeze
Sea breeze—local wind blowing from sea toward the land, usually during the day.

Sea and Land Breezes
Valley and Mountain Breezes
Valley and mountain breeze
Mountain air cools quickly at night, allowing cooler air to drain down the slope in the evening.
Conversely, valley air heats more rapidly during the day, allowing warm air to move upslope during the day.
Valley breeze—an upslope flow, during day.
Mountain breeze—a downslope flow, during night.

Valley Breezes
Mountain Breezes
Foehn/Chinook Winds
Chinook—a localized downslope wind of relatively dry and warm air, which is further warmed adiabatically as it moves down the leeward slope of the Rocky Mountains.

Chinook Winds

A computer system that stores, organizes, retrieves, analyzes, and displays geographic data is
A) GIS.
B) GPS.
C) Remote sensing.
D) USGS.

The first person to use the word geography was
A) Aristotle.
B) Eratosthenes.
C) Strabo.
D) Thales of Miletus

__________________ goes from a set of specific observations to general
A. Inducative reasoning
B. Deductive reasoning
C. Literature review
D. Hypothesis

A prediction about a specific case based on the general premises is ____________
A. Deductive reasoning
B. Deductive reasoning
C. Literature Review
D. Hypothesis


All conformal projections have meridians and parallels crossing each other at right angles, just as they do on the globe.
A. true
B. False

The scale of a map can never be constant all over the entire map.
A. True
B. False

On Mercator projection, Greenland's size relative to the United States is greatly exaggerated
A. True
B. false

The original purpose of the Mercator projection was for navigation.
A. True
B. False

“Equivalency" in map projections means having no scale changes over the entire map
A. True
B. False

Maps are inherently inaccurate because of their attempt to depict the curved Earth on a flat surface.
A. True
B. False

Portraying the Earth
The Nature of map
A two-dimensional representation of the earth and the spatial distribution of selected phenomena

Defining map…
It is a scaled drawing of a portion of a landscape representing the area at a reduced scale and showing only selected data.
Basic attributes of maps
Ability so show distance, direction, size, and shape in their horizontal spatial relationship

Shows distribution of one or more phenomena
Maps and Map Projections
How Maps Can Mislead Us
A Globe
Is the only truly accurate representation of the earth
A flat surface
It is easy to portray a flat surface on a flat piece of paper

But there is no way to accurately portray a 3-dimensional round surface on a flat piece of paper



Therefore all maps are distorted
Distortion will occur in at least one of these three map components:
Size (area)
Shape
Distance

Major dilemma
Impossible for cartographers to portray on a map, the accurate size and shape of objects of the earth surface, without a compromise.
The questions is; Which to sacrifice shape or Size?


Equivalence verses Conformality
These are the two properties of map projections

Equivalent
A map that is equivalent is accurate in size or area
Also known as Equal Area projection
It is NOT going to be accurate in shape
Peter’s map is equivalent
Conformal
A map that is conformal is accurate in shape

It will NOT be accurate in size (area)
Mercator map is conformal
A world map cannot be both equivalent and conformal


Equivalence and conformality are mutually exclusive properties
Making Maps
Mapmakers have devised many different methods for making maps of the world

Projections
The different methods are called “projections”

The term projection refers to projecting the 3-dimensional globe onto a flat surface

Major challenges
How to transfer data from a spherical surface to a flat piece of paper without distortions

Common Map Projections
Cylindrical
Conical
Planar or polar
Cylindrical Projections
Commonly used for world maps
Distort size (area) more in areas farthest away from the equator
Most prominent in northern latitudes since most of the northern hemisphere’s land mass is far from the equator
Mercator is the most common cylindrical projection
Cylindrical
Conical Projections
Most often used to portray continents in the mid latitudes
North America
Europe
South America

Not useful for a world map
Conical
Polar Projections
Can only show one hemisphere

Most often used to portray the Arctic Ocean in the northern hemisphere or Antarctica in the southern hemisphere

A semi-polar projection is useful in portraying the former Soviet Union
Planar or Polar (Azimuth)
Tangency
Each projection is accurate at the point(s) of tangency only
Cylindrical: equator (line)
Conic: mid latitude (line)
Planar: one pole only (point)

The further away from the point(s) of tangency, the more distortion
tangency


Tangency…
The distortions increase as the distance from the central point of the projection increases.


Other Projections
Various ways to minimize distortion in one aspect while keeping accuracy in the other aspect have been invented

Mollewide
Robinson
Goode’s Homolosine (interrupted)
Distortion Compared
Maps projections
http://www.youtube.com/watch?v=AI36MWAH54s&feature=related


Map scale
Map scale gives the relationship between the length measured on the map and the corresponding actual distance on the ground
Scale can never be represented with perfect accuracy……
Why??????
Nature of map scales
Scales can never be constant (same) over the entire map
Small area may have a nearly perfect scale with less variation
Large area may have a scale variations
Scale Types
Three types of scales
Graphic map scale
Fractional map scale
verbal map scale

Verbal scale Map scale
1 inch equals 16 miles
Thus 1-inch on the map represents 16 miles on the surface of the Earth.
This is the easiest scale to understand because it generally uses familiar units.


Graphic or bar scale
B. Graphic or Bar Scale:
_____________________________________
_____16________0________16_________32_ miles
The Bar Scale is particularly important when enlarging or reducing maps by photocopy techniques because it changes with the map. If the Bar Scale is included in the photocopy, you will have an indication of the new scale.
Fractional map scale
1:1,000,000 (this is the same as 1/1,000,000)
The RF says that 1 of any measurement on the map equals 1 million of the same measurement on the original surface;
commonly used in the Map Collection.
A good quality map should have both the RF and Bar Scales.

Examples of Map Scales
Legend
The legend is the key to reading the map
Defines the colors and symbols used on the map
The map scale will be found there
Ratio
1:10,000
Fractional
1/10,000
Words
“One inch equals ten-thousand inches”
Graphic – looks like a ruler

Large Scale vs. Small Scale
A large scale map portrays a small part of earth’s surface
City
Campus
Classroom

Anything with the second number of the scale ratio less than 60,000 is considered a large scale map



A small scale map portrays a large portion of earth’s surface
World map – the smallest scale of all
1:13,000,000 is the scale of our wall map

Anything with the second number larger than 60,000 is considered a small scale map
Extremely small scale maps,
like world maps, have the
most distortion
Large scale maps, like a map of the college campus, have little or no distortion
Types of Maps
Maps are generally made for a specific purpose
Road Map
Shows roads, towns, cities, and other data useful for transportation

Probably the most familiar to the average person

But there are many other types of maps!
Political
Show man-made divisions, such as the borders of states or countries

Physical
Show physical characteristics, like mountains, lakes, and rivers
Often show elevation by color coding
Topographic
Show landforms and elevations in detail

Often use isolines, lines that connect places with equal value, in this case “feet above sea level”
Thematic
Physical
Climate
Ocean Currents
Biomes

Cultural
Population
Ethnicity
Income


Map of World Population
Automated Cartography

Computer technology has provided several great benefits to cartography:
Improved speed and data-handling ability;
Reduced time involved in map production;
Ability for cartographer to examine alternative map layouts.
Cartographic devices
Isolines : any line that joins points of equal value of something

Contour line—joins points of equal elevation;
Isobar—joins points of equal atmospheric pressure;
Isogonic line—joins points of equal magnetic declination;
Isohyet—joins points of equal quantities of precipitation;
Isotherm—joins points of equal temperature.

Basic characteristic of Isolines
They are always closed lines, having no ends;
They represent gradations in quantities, so only touch or cross one another in very rare and unusual circumstances.
Isolines close together indicate a steep gradient
The Global Positioning system-
GPS
It is a satellite-based systems for determining accurate positions on or near Earth’s surface

Global Positional System
It was developed by the Department of Defense in the 1970s and 1980s to provide a reliable and accurate positioning system for mobile military platforms operating around the world.
How it operates
It is Based on a network of 24 high-Altitude satellite configured so that a minimum of four are in view of any position on earth
the system enables a GPS receiver to determine its location, speed/direction, and time.

GPS
Each satellite continually transmits both identification and positioning which can be picked by receivers on earth
Remote sensing
It is any measurement or acquisition of information by a recording device that is not in direct contact with the object under study
Remote sensing
Types: Passive and Active
Passive system : here the satellite works by sensing the natural radiation emitted or reflected from an object.
Active system: the satellite has its own source of electromagnetic radiation.
EX.
Radar- it is able to penetrate atmospheric moisture
Sonar: This permits underwater imaging



USES
makes it possible to collect data on dangerous or inaccessible areas
Replaces costly and slow collection on the ground, ensuring in the process that areas or objects are not disturbed.
Aerial Photographs
It is one taken from an elevated platform such as a balloon, airplane or rocket
Depending on camera angle there are two classification of aerial photographs
Oblique
Vertical
Oblique aerial photograph
Here the camera angle is less than 90˚
The features are seen from a more or less familiar point of view
Vertical Aerial photographs
Pictures are taken with the optical axis of the camera approximately perpendicular to the surface of the earth
Geographic Information Systems (GIS)
An Automated systems for the capture, storage, retrieval, analysis, and display of spatial data

latitudes and Longitudes earth-sun relation

Earth sphere
The earth’s sphere
Earth’s surface is a complex interface where four spheres meet, and to some degree overlap and interact.
Lithosphere
Atmosphere
Hydrosphere
Biosphere

lithosphere
The lithosphere is the solid portion of the Earth
Atmosphere
Contains the complex mixture of gasses to sustain life
Hydrosphere
Comprises water in all its form
biosphere
Comprise all part of earth where living organisms can exist:
Comprise of variety of earthly life forms
The Solar system
http://video.nationalgeographic.com/video/player/science/index.html

The size and shape of the earth
Earth is an oblate spheroid rather than a true sphere
Earth shape is affected by two main facts:
It bulges in midriff, because of pliability of Earth’s lithosphere;
It has topographical irregularities.
In context of Earth’s full dimensions, these variations are minute
Size and Shape of Earth
How to Find locations on the earth surface
Geographic grid
Earth’s natural reference points
North Pole
South Pole
Equatorial planes
Rotational Axis

The equatorial plane
It an imaginary plane that passes through earth halfway between the poles and perpendicular to the axis of rotation
1. Axis of rotation
It is an imaginary line that connects the points of the earth surface called North Pole and South Pole

The Geographic Grid
The Equator
Great Circles and Small Circles
Latitude
Longitude
The Equator

Great and Small Circles
Latitude: Parallels
Longitude: Meridians
Important Latitudes

Nautical Miles
Each degree of latitude on the earth surface covers a north south distance of about 111km( 69miles)
Distance varies with latitudes because of the flattening of earth at the poles
What is the relationship between the earth and the Sun?

Earth-Sun Relations
Life on earth is dependent on solar energy
The relationship between the earth and the sun does not remain the same because of the movement of the earth

Earth Movement
Daily Rotation on its axis
Annual Revolution around the sun
Daily Earth Rotation On Its Axis
Earth rotates from West to East in a counterclockwise direction
One rotation of the Earth takes about 24 hours and it equals a one day.

Earth’s daily rotation
1.Coriolis Effect
Deflection in the flow path of both air and water current.
To the right in the Northern Hemisphere
To Left in the Southern Hemisphere
Coriolis Effect
2. Gravitation pull
Onshore and offshore rhythmic movement of ocean water
Rise and fall of water level ( tides)
3. Night and day
4. stars, sun, moon and planets appear to rise in the east
As the Earth rotates to the East, any object not attached to it will seem to drift to the West.
This is why the stars, Sun, Moon, and planets all rise in the East, and set in the West.

Earth’s Revolution
Earth’s revolution around the sun takes 365¼ days in a counterclockwise Direction
The path that the earth follows is elliptical – not circular.…because of that, the earth-sun distance is not constant.

Earth-sun distance
Closest at 147,166,480km ( 91,455,000miles) also known as Perihelion on or about January 3rd. Farthest at 152,171,500 (94,555,000miles) also known as Aphelion on or about July 4th
Basics of the earth positions
http://esminfo.prenhall.com/science/geoanimations/animations/01_EarthSun_E2.html

The Plane of the ecliptic
The plane of the ecliptic is a plane that cuts through the center of the Earth and the Sun in which the Earth revolves around the Sun.

Inclination of the earth
The Earth's axis is tilted 23 1/2 degrees from being perpendicular to the plane of the ecliptic.
Polarity of Earth’s Axis
The axis of rotation remains pointing in the same direction as it revolves around the Sun, pointing toward the star Polaris
Parallelism…

The seasons
The combined effect of;
Rotation,
Revolution,
Inclination, and
Polarity result in the seasonal patterns experienced on earth
March of the Seasons
Seasons
The seasons are caused because the Earth is tilted 23.5 degrees on its axis.
Summer happens to the hemisphere tilted towards the Sun, and
Winter happens to the hemisphere tilted away from the Sun
June solstice
This occur on or about June 21
The Ray of the sun at noon are striking perpendicular to the surface of tropic of cancer, 23.5°north of the equator
All point north of 66.5°north experience 24 continuous hours of daylight
The June solstice is called the Summer Solstice in the Northern Hemisphere, Winter solstice in the southern Hemisphere. Thus the first day of summer in the Northern Hemisphere and the first day of winter in the Southern Hemisphere
September Equinox
This occurs on or about September 22
Here the vertical rays of the sun strikes at the equator
All locations on earth receive 12 hours of daylight and 12 hours of darkness. September equinox is called Autumnal equinox in the Northern Hemisphere and Vernal equinox in the southern Hemisphere
December Solstice
This occurs on or about December 21
Here the North pole is oriented directly away from the sun.
The vertical rays of the sun strikes 23.5°s, Tropic of Capricorn.This is called winter Solstice in the Northern Hemisphere and the summer solstice in the Southern Hemisphere
The first day of winter in the Northern Hemisphere.First day of summer in the southern Hemisphere
March Equinox
This occurs on or about March 20th.This is similar to the September equinox
It is called Vernal Equinox in the Northern Hemisphere and Autumnal equinox in the southern Hemisphere.Earth-sun relations
http://www.youtube.com/watch?v=taHTA7S_JGk

Significance of seasonal Patterns
Day length, and angle at which the sun’s rays strike the earth surface are the principal determinant of amount of solar energy receives at any particular latitudes are;

INTRO. TO GEOGRAPHY

Introduction to Geography
What is Geography?
Earth description
Two Greek words
‘geo’ =earth
‘graphy’ = description
Geography = Earth description
The first person to use the word geography was Eratosthenes
Areal differentiations…
Geographers study how things differ from place to place
2 broad things???
Natural in origin (physical geography)
Human endeavors (human geography)
Branches of Geography
1. Cultural/ Human Geography
2. Physical/ Environmental Geography
Cultural Geography
The elements are those of human endeavors. Examples
Population
Settlements
Economic activities
Transportation
Recreation activities
Religion
Languages
Political systems
Traditions etc
Physical Geography
The study of the natural processes that shape the surface of the Earth and life on it;
It is concerned with processes and patterns in the natural world.
The elements are natural in origin.
Earth surface
Rocks
Landforms
Soils
Flora
Fauna
Climate
Water
Minerals

Discipline of geography
Geography is also concerned with interrelationship of phenomena on earth surface
Environmental determinism
Environmental Possibilism

Geography is both a physical science and social science because it combines characteristics of both Knowledge in the natural world is advanced through the use of scientific methods

Art and science
Science is a process of following a set of predetermined guides in order to achieve a result.
An Art, by contrast, takes the power of metaphor and independent thought inherent in the human mind to bear in order to create something. How do geographers study natural processes using the scientific method?

What is a scientific method?
Scientific method is a body of techniques for investigating phenomena and acquiring new knowledge,For correcting and integrating previous knowledge. What are the processes involved?
1.Observation and Description
This include reading and studying what others have done in the past because scientific knowledge is cumulative
2. Formulation of Hypothesis
This is a tentative answer to the question: a testable explanation for what was observed
An hypothesis is not an observation, rather, a tentative explanation for the observation
3. Prediction
Use of the hypothesis to predict the existence of other phenomena, or to predict quantitatively the results of new observations.
Two types
Inductive reasoning
Deductive reasoning

Inductive reasoning goes from a set of specific observations to general conclusions: I observed cells in x, y, and z organisms, therefore all animals have cells.
From specifics observation to generalization
Deductive reasoning
Deductive reasoning flows from general to specific. From general premises, a scientist would extrapolate to specific results:Ex. if all organisms have cells and humans are organisms, then humans should have cells. This is a prediction about a specific case based on the general premises.

4.Experimentation and conclusion
4. Performance of experimental tests of the predictions by several independent experimenters
Good sciences tend to be cautious in the conclusion that are drawn.“ the evidence suggests…, the results most likely….The result becomes a theory
Theory
A theory is a generalization based on many observations and experiments;
It is a well-tested, verified hypothesis that fits existing data and explains how processes or events are thought to occur
The acceptance of scientific ideas and theories are based on evidence, not on beliefs

Geographic questions?
Where?- location
Why?- explanation
What?- description/definition
How?-impact/processes of formation
How Do Geographers Describe Where Things are?

Map
Contemporary tools

Map
A map is a two-dimensional or flat-scale model of the earths surface, or a portion of it.
The science of mapmaking is called Cartography.Two important uses of Map
A map serves two purposes:
A tool for storing reference materials
A tool for communicating geographic information

Contemporary tools
Remote Sensing
Geographic Information System
Remote Sensing
The acquisition of data about earth’s surface from a satellite orbiting earth or from other long-distance method
Geographic Information System(GIS)
A computer-based system designed to collect, store, integrate, manipulate, analyze & display data in a spatially referenced environment.

5 Geographic Themes
Location
Place
Movement
Human/environmental relations
Region

Physical geography
The place of earth in the solar system
The basic physical characteristics of this planet
The functional relationship between Earth and the sun