Chapter 2Chapter 2

The Physical WorldThe Physical WorldObjectiveObjective: understanding the physical aspects : understanding the physical aspects

of geographyof geography

Why to understand physical Why to understand physical features?features?

A description of a physical place includes the A description of a physical place includes the characteristics of the land formation, characteristics of the land formation, including types of water in the area. including types of water in the area.

The terrain of the area (e.g. mountains, hills, The terrain of the area (e.g. mountains, hills, valleys, plateaus, etc.), the related vegetation, valleys, plateaus, etc.), the related vegetation, and the type of surface water affect the and the type of surface water affect the potential activities (sports and other outdoor potential activities (sports and other outdoor activities – e.g. hiking, boating, fishing etc.) activities – e.g. hiking, boating, fishing etc.) that can be conducted by the travelers.that can be conducted by the travelers.

Land and water may attract the traveler who Land and water may attract the traveler who has varies needs. has varies needs.

Major Land and Water Major Land and Water Forms Forms

BayBay CanyonCanyon CapeCape CoastCoast DeltaDelta FjordFjord GlacierGlacier GulfGulf IsthmusIsthmus PeninsulaPeninsula

PlainPlain PlateauPlateau StraitStrait ArchipelagoArchipelago CayCay DuneDune FoothillsFoothills LagoonLagoon ReefReef

Latitude and LongitudeLatitude and Longitude Where are we?Where are we? The latitude and longitude system is used to The latitude and longitude system is used to

locate points on the earth’s surface.locate points on the earth’s surface. The system is expressed in degrees ( ° ). For The system is expressed in degrees ( ° ). For

exact positioning, degrees longitude and exact positioning, degrees longitude and latitude are divided into minutes ( latitude are divided into minutes ( '' ) and ) and seconds ( seconds ( "" ) )

E.g. Washington D.C. 38° 53E.g. Washington D.C. 38° 53 '' 23 23"" N, 77° 00 N, 77° 00'' 2727"" W (38 degrees, 53 minutes, and 23 W (38 degrees, 53 minutes, and 23 seconds north of the equator and 77 degrees, seconds north of the equator and 77 degrees, no minutes and 27 seconds west of the no minutes and 27 seconds west of the meridian passing through Greenwich, meridian passing through Greenwich, England)England)

LatitudeLatitude Are also called parallels.Are also called parallels. Lines of latitude express relative position Lines of latitude express relative position

north or south of the equator (zero degrees north or south of the equator (zero degrees latitude). latitude).

Zero degrees is the equator, the imaginary line Zero degrees is the equator, the imaginary line which divides the planet into northern and which divides the planet into northern and southern hemispheres.southern hemispheres.

Latitude is measured from 0° to 90° north or Latitude is measured from 0° to 90° north or south. 90° north is the North Pole and 90° south. 90° north is the North Pole and 90° south is the South Pole.south is the South Pole.

The climate is usually similar at latitudes that The climate is usually similar at latitudes that are an equal distance north or south of the are an equal distance north or south of the equator.equator.

Each degree of latitude is approximately Each degree of latitude is approximately 111km apart. Since the shape of the earth 111km apart. Since the shape of the earth is not a perfect sphere but an oblate is not a perfect sphere but an oblate ellipsoid, there is variation.ellipsoid, there is variation.

LongitudeLongitude

Are also called meridians.Are also called meridians. Lines of longitude run north and south Lines of longitude run north and south

between North Pole and South Pole. between North Pole and South Pole. Zero degrees longitude is established at the Zero degrees longitude is established at the

Greenwich Observatory, England and is called Greenwich Observatory, England and is called the “prime meridian” or “Greenwich the “prime meridian” or “Greenwich Meridian”.Meridian”.

Longitude is measured east and west from this Longitude is measured east and west from this prime meridian. The degrees continue 180° prime meridian. The degrees continue 180° east and 180° west (half way around the world) east and 180° west (half way around the world) where they meet and form “The International where they meet and form “The International Date Line” in the Pacific Ocean.Date Line” in the Pacific Ocean.

The world can be divided into hemispheres in The world can be divided into hemispheres in two primary ways – Eastern/Western and two primary ways – Eastern/Western and Northern/Southern. Northern/Southern.

The Eastern Hemisphere includes all The Eastern Hemisphere includes all meridians of East Longitude from 0° to 180°; meridians of East Longitude from 0° to 180°; while the Western Hemisphere includes all while the Western Hemisphere includes all meridians of West Longitude. meridians of West Longitude.

The Northern/Southern splits the world at The Northern/Southern splits the world at the equator with all parallels of North the equator with all parallels of North Latitude in the Northern Hemisphere and all Latitude in the Northern Hemisphere and all parallels of South Latitude in the Southern parallels of South Latitude in the Southern Hemisphere.Hemisphere.

World Latitude and Longitude Outline Map:World Latitude and Longitude Outline Map:

http://www.enchantedlearning.com/geographhttp://www.enchantedlearning.com/geography/world/latlongoutlinemap/y/world/latlongoutlinemap/

To locate the coordinates of To locate the coordinates of a point;a point;

Peak a city as an example.Peak a city as an example. For LatitudeFor Latitude: find the equator. : find the equator.

Determine if the city is north or south Determine if the city is north or south the equator. (N or S) the equator. (N or S)

Always measures north and south.Always measures north and south. Determine which two lines of latitude Determine which two lines of latitude

the city is in between.the city is in between. Determine if the city is closer to the Determine if the city is closer to the

midpoint or one of the lines.midpoint or one of the lines. Estimate the degrees Latitude. Estimate the degrees Latitude.

For LongitudeFor Longitude: Find the prim : Find the prim meridian. Determine if the city is meridian. Determine if the city is East or West of the Prime Meridian. East or West of the Prime Meridian. (E or W)(E or W)

Always measure east and west.Always measure east and west. Determine which two lines of Determine which two lines of

longitude the city is in between.longitude the city is in between. Determine if the city is closer to the Determine if the city is closer to the

midpoint or one of the lines.midpoint or one of the lines. Estimate the degrees Longitude. Estimate the degrees Longitude.

Latitude/Longitude ChartLatitude/Longitude Chart

City NameCity Name LatitudeLatitude N/SN/S LongitudLongitudee

E/WE/W

11

22

33

44

55

66

77

88

Time ZonesTime Zones

World time varies in a direct relationship to World time varies in a direct relationship to longitudinal location of a point. longitudinal location of a point.

Earth rotates 15 degrees every hour. (There Earth rotates 15 degrees every hour. (There are 360 degrees of longitude - 180 East and are 360 degrees of longitude - 180 East and 180 West – on the earth and 24 hours in a 180 West – on the earth and 24 hours in a day day 360 / 24 = 15 degrees per hour). 360 / 24 = 15 degrees per hour). Thus, there is a difference of one hour for Thus, there is a difference of one hour for each 15 degrees difference in longitude. each 15 degrees difference in longitude.

In order to have the sun at its highest point In order to have the sun at its highest point in sky at noon everywhere around the in sky at noon everywhere around the world, we need multiple “time zones”. world, we need multiple “time zones”.

Determining TimeDetermining Time

A plane leaves Munich at 7:00 A plane leaves Munich at 7:00 Sunday to go to New York City. Sunday to go to New York City. What time will it be in New York What time will it be in New York City? (flight duration is 8 hours)City? (flight duration is 8 hours)

Multiple time zones divide the world Multiple time zones divide the world into 24 15-degree slices and set the into 24 15-degree slices and set the clocks accordingly in each zone.clocks accordingly in each zone.

Each zone is one hour different from Each zone is one hour different from the next. the next.

Greenwich Mean Time Greenwich Mean Time (GMT)(GMT)

When time is concerned, why is the When time is concerned, why is the Greenwich Observatory such a big deal? Greenwich Observatory such a big deal?

World time is measured in terms of World time is measured in terms of relationship to the time at the Greenwich relationship to the time at the Greenwich Observatory, England known as the “Prime Observatory, England known as the “Prime Meridian”.Meridian”.

Time at the Greenwich Meridian is known as Time at the Greenwich Meridian is known as “Greenwich Mean Time” (GMT) or Universal “Greenwich Mean Time” (GMT) or Universal Time. Time.

The Chart, on page 8 of your course book, The Chart, on page 8 of your course book, shows places (countries, cities etc.), number shows places (countries, cities etc.), number of hours later (+) or earlier (-) than GMT. of hours later (+) or earlier (-) than GMT.

What Time Zone Is It?What Time Zone Is It? While traveling (for example, from Munich While traveling (for example, from Munich

to New York City), to calculate the time at to New York City), to calculate the time at the arrival point (may be the time in air as the arrival point (may be the time in air as well), the number of time zones crossed well), the number of time zones crossed need to be considered. need to be considered.

Since straight longitudes (time zones) can Since straight longitudes (time zones) can cut across countries, time differences are cut across countries, time differences are usually established along political usually established along political boundaries. For example, China uses a boundaries. For example, China uses a single time zone and sets its clock to the single time zone and sets its clock to the time in its capital, Beijing. On the other time in its capital, Beijing. On the other hand, in the US, there are four time zones – hand, in the US, there are four time zones – Eastern, Central, Mountain and Pacific.Eastern, Central, Mountain and Pacific.

Example 1AExample 1A

If it is 14:00 in New York City (GMT-5), If it is 14:00 in New York City (GMT-5), what time is it in Paris, France (GMT+1)?what time is it in Paris, France (GMT+1)?

time in New York (GMT-5)time in New York (GMT-5) 14:0014:00 GMT is GMT is 19:00 (14:00 plus 5 19:00 (14:00 plus 5

hours)hours) time in Paris (GMT+1)time in Paris (GMT+1) 20:00 (19:00 plus 1 20:00 (19:00 plus 1

hour)hour)

PS: note that the time difference between New PS: note that the time difference between New York and Paris is 6 hours.York and Paris is 6 hours.

Example 1BExample 1B

If it is 14:00 on a Monday in New York City If it is 14:00 on a Monday in New York City (GMT-5), what time is it in Sydney, Australia (GMT-5), what time is it in Sydney, Australia (GMT+10)?(GMT+10)?

time in New York (GMT-5)time in New York (GMT-5) 14:00 on Monday14:00 on Monday GMT is GMT is 19:00 (14:00 plus 5 19:00 (14:00 plus 5

hours)hours) time in Sydney (GMT+10)time in Sydney (GMT+10) 05:00 on 05:00 on

Tuesday (19:00 plus 10 hours)Tuesday (19:00 plus 10 hours)

PS: note that the time difference between New York PS: note that the time difference between New York and Sydney is 15 hours.and Sydney is 15 hours.

Example 1CExample 1C

If it is 07:00 in Moscow (GMT+3), what If it is 07:00 in Moscow (GMT+3), what time is it in Tokyo, Japan (GMT+9)?time is it in Tokyo, Japan (GMT+9)?

time in Moscow (GMT+3)time in Moscow (GMT+3) 07:0007:00 GMT is GMT is 04:00 (07:00 minus 04:00 (07:00 minus

3 hours)3 hours) time in Tokyo (GMT+9)time in Tokyo (GMT+9) 13:00 (04:00 plus 9 13:00 (04:00 plus 9

hours)hours)

PS: note that the time difference between Moscow PS: note that the time difference between Moscow and Tokyo is 6 hours.and Tokyo is 6 hours.

Example 2Example 2

A plane leaves Munich at 7:00 Sunday to go to A plane leaves Munich at 7:00 Sunday to go to New York City. What time will it be in New York New York City. What time will it be in New York City? (flight duration is 8 hours)City? (flight duration is 8 hours)

plane departs atplane departs at 07:00 in Munich (GMT+1)07:00 in Munich (GMT+1) GMT is GMT is 06:00 (07:00 minus 1 hour)06:00 (07:00 minus 1 hour) flight durationflight duration 8 hours8 hours flight landing at GMT isflight landing at GMT is 14:00 (06:00 plus 8 14:00 (06:00 plus 8

hours)hours) time in New York (GMT-5)time in New York (GMT-5) 09:00 (14:00 minus 5 09:00 (14:00 minus 5

hours)hours)

PS: note that although the flight duration is 8 hours, PS: note that although the flight duration is 8 hours, departure from Munich was 07:00 and arrival to New departure from Munich was 07:00 and arrival to New York was 09:00.York was 09:00.

Example 3AExample 3A

If a plane leaves Istanbul (GMT+2) at 10:00 and If a plane leaves Istanbul (GMT+2) at 10:00 and lands in New York (GMT -5) at 15:00 local time, lands in New York (GMT -5) at 15:00 local time, calculate the journey time?calculate the journey time?

plane arrives at plane arrives at 15:0015:00 in New York (GMT-5)in New York (GMT-5) GMT is GMT is 20:0020:00 (15:00 plus 5 hours)(15:00 plus 5 hours) plane departed at plane departed at 10:00 10:00 from Istanbul from Istanbul

(GMT+2)(GMT+2) GMT isGMT is 08:0008:00 (10:00 minus 2 hours)(10:00 minus 2 hours) the journey time is the journey time is 20:00 minus 8:00 20:00 minus 8:00 12 12

hourshours

PS: (10:00 Istanbul time PS: (10:00 Istanbul time 22:00 Istanbul time 22:00 Istanbul time 15:00 15:00 New York time) New York time) time advantagetime advantage when traveling to westwhen traveling to west

Example 3BExample 3B

If a plane leaves Istanbul (GMT+2) at 18:00 on If a plane leaves Istanbul (GMT+2) at 18:00 on 2424thth of Feb and lands in Bishkek (GMT +5) at of Feb and lands in Bishkek (GMT +5) at 02:00 on 2502:00 on 25thth of Feb, calculate the journey time? of Feb, calculate the journey time?

plane arrives at plane arrives at 02:00 on 25 Feb in Bishkek (GMT+5)02:00 on 25 Feb in Bishkek (GMT+5) GMT is GMT is 21:00 on 24 Feb 21:00 on 24 Feb (02:00 minus 5 (02:00 minus 5

hours)hours) plane departed at plane departed at 18:00 on 24 Feb from Istanbul 18:00 on 24 Feb from Istanbul

(GMT+2)(GMT+2) GMT isGMT is 16:00 on 24 Feb 16:00 on 24 Feb (18:00 minus 2 (18:00 minus 2

hours)hours) the journey time is the journey time is 21:00 minus 16:00 21:00 minus 16:00 5 hours 5 hours

PS: (18:00 Istanbul time PS: (18:00 Istanbul time 23:00 Istanbul time 23:00 Istanbul time 02:00 02:00 on 25 Feb Bishkek time) on 25 Feb Bishkek time) time losttime lost when traveling to when traveling to east (be careful with IDL)east (be careful with IDL)

International Date LineInternational Date Line The International Date Line is the imaginary The International Date Line is the imaginary

line on earth that separates two consecutive line on earth that separates two consecutive calendar days. calendar days.

The International Date Line is located half way The International Date Line is located half way around the planet from Greenwich, England. around the planet from Greenwich, England.

It is both 12 hours ahead of GMT and 12 hours It is both 12 hours ahead of GMT and 12 hours behind GMT.behind GMT.

It has been recognized as a matter of It has been recognized as a matter of convenience. Travelers to westward would convenience. Travelers to westward would discover that when they returned home, one discover that when they returned home, one day more than they through has passed. This day more than they through has passed. This first happened to Magellan.first happened to Magellan.

When the International Date Line is crossed When the International Date Line is crossed from the east to the west, a calendar day must from the east to the west, a calendar day must be added. When the line is crossed from the be added. When the line is crossed from the west to the east, a calendar day must be west to the east, a calendar day must be subtracted. subtracted.

For example, the Fiji Islands (GMT +12) are For example, the Fiji Islands (GMT +12) are west of the International Date Line but the west of the International Date Line but the Samoan Islands (GMT -11) are to the east. Samoan Islands (GMT -11) are to the east. When it is 15:00 on Tuesday in the Fiji Islands When it is 15:00 on Tuesday in the Fiji Islands it is still 16:00 on Monday in the Samoan it is still 16:00 on Monday in the Samoan Islands, even though the distance between the Islands, even though the distance between the groups of islands is no more than 800 miles. groups of islands is no more than 800 miles.

Fiji (GMT+12)Fiji (GMT+12) Samoa (GMT -11)Samoa (GMT -11)TuesdayTuesday MondayMonday

IDLIDL

For example, in a trip to the US from Japan on For example, in a trip to the US from Japan on a Monday morning, when the International a Monday morning, when the International Date Line is crossed, the day changes to Date Line is crossed, the day changes to Sunday. On a reverse trip on a Tuesday Sunday. On a reverse trip on a Tuesday morning, when the line is crossed, the day morning, when the line is crossed, the day changes to Wednesday.changes to Wednesday.http://geography.miningco.com/cs/http://geography.miningco.com/cs/timetimezones/index_2.htmtimetimezones/index_2.htm

The International Date Line is not a straight The International Date Line is not a straight line. There are zigs and zags in it to avoid line. There are zigs and zags in it to avoid spitting apart countries into two days. Lately, spitting apart countries into two days. Lately, in 1995, Kiribati moved a large part of it to in 1995, Kiribati moved a large part of it to the east to be on the same side of the IDL. the east to be on the same side of the IDL. http://aa.usno.navy.mil/faq/docs/http://aa.usno.navy.mil/faq/docs/international_date.htmlinternational_date.html

ClimateClimate One of the most important factors which One of the most important factors which

affects where people choose to travel affects where people choose to travel (+proper clothing, likelihood of rain, nature of (+proper clothing, likelihood of rain, nature of the terrain, etc.) is climate, especially true for the terrain, etc.) is climate, especially true for rest and relaxation type vacations.rest and relaxation type vacations.

Climate and weather are different things. Climate and weather are different things. Climate is the average state or condition over Climate is the average state or condition over

a long period of time in an area. It refers to a a long period of time in an area. It refers to a large geographical region. It is quite large geographical region. It is quite predictable.predictable.

Weather is the atmospheric condition (e.g. Weather is the atmospheric condition (e.g. temperature, precipitation, etc) at any given temperature, precipitation, etc) at any given moment in a specific (small) location. It can moment in a specific (small) location. It can only be predicted on a short term basis.only be predicted on a short term basis.

Factors affecting climateFactors affecting climate

There are four primary factors There are four primary factors affecting the climate of a location:affecting the climate of a location: Latitude (location north or south of the Latitude (location north or south of the

equator)equator) Mountains – altitude lowers temperature Mountains – altitude lowers temperature

and prevents weather patterns from and prevents weather patterns from crossingcrossing

Proximity to major bodies of waterProximity to major bodies of water Prevailing wind and ocean current Prevailing wind and ocean current

patternspatterns

Latitudinal positionLatitudinal position

The equator is the line of latitude which The equator is the line of latitude which splits the world into the Northern and splits the world into the Northern and Southern Hemispheres. A destination’s Southern Hemispheres. A destination’s climate changes depending on how far it climate changes depending on how far it is from the equator. is from the equator.

Based on the distance from the equator, Based on the distance from the equator, there are 5 different temperature zones there are 5 different temperature zones on earth.on earth. Tropical ZoneTropical Zone North & South Temperature ZonesNorth & South Temperature Zones North & South Polar ZonesNorth & South Polar Zones

Tropical ZoneTropical Zone: the area between : the area between “Tropic of Cancer” (23,5° North “Tropic of Cancer” (23,5° North Latitude) and the “Tropic of Capricorn” Latitude) and the “Tropic of Capricorn” (23,5° South Latitude). There are only (23,5° South Latitude). There are only minimal changes in warm temperatures minimal changes in warm temperatures throughout the year. throughout the year.

Caribbean islands lie within the tropics. Caribbean islands lie within the tropics. On the other hand, the Bahamas and On the other hand, the Bahamas and Florida are located just north of the Florida are located just north of the Tropic of Cancer. Their climate is Tropic of Cancer. Their climate is considered subtropical where winter considered subtropical where winter days are cooler. days are cooler.

North Temperature ZoneNorth Temperature Zone: the area : the area between the Arctic Circle (66,5° North between the Arctic Circle (66,5° North Latitude) and the Tropic of Cancer. Latitude) and the Tropic of Cancer.

South Temperature ZoneSouth Temperature Zone: the area : the area between the Antarctic Circle (66,5° South between the Antarctic Circle (66,5° South Latitude) and the Tropic of Capricorn. Latitude) and the Tropic of Capricorn.

Locations within the temperature zones Locations within the temperature zones are characterized by changes in are characterized by changes in temperature through the four seasons. temperature through the four seasons. The northern the Tropic of Cancer and The northern the Tropic of Cancer and the southern the Tropic of Capricorn, the the southern the Tropic of Capricorn, the climate is colder.climate is colder.

North Polar ZoneNorth Polar Zone: the area : the area between the Arctic Circle and the between the Arctic Circle and the North Pole.North Pole.

South Polar ZoneSouth Polar Zone: the area : the area between the Antarctic Circle and the between the Antarctic Circle and the South Pole. South Pole.

Polar Climate is normally below Polar Climate is normally below freezing at all times.freezing at all times.

The effects of mountainsThe effects of mountains

Altitude has a cooling effect on Altitude has a cooling effect on climate conditions. The higher the climate conditions. The higher the location, the cooler the climate. location, the cooler the climate.

Lapse rateLapse rate: for every 305m in : for every 305m in elevation you rise, the temperature elevation you rise, the temperature drops 1,5 degree Celsius.drops 1,5 degree Celsius.

There is often winter snow near Los There is often winter snow near Los Angeles, California, but nothing at Angeles, California, but nothing at the valley below.the valley below.

Mountains, because of their height, Mountains, because of their height, prevent many weather patterns from prevent many weather patterns from crossing from the windward (the side crossing from the windward (the side of a mountain that the wind hits, of a mountain that the wind hits, generally wetter and greener ) to the generally wetter and greener ) to the leeward (the side of a mountain that leeward (the side of a mountain that is sheltered from the wind, generally is sheltered from the wind, generally drier than the other side) side. Thus drier than the other side) side. Thus on opposite sides of mountain ranges, on opposite sides of mountain ranges, considerably different levels of considerably different levels of precipitation can be found. precipitation can be found.

Proximity to waterProximity to water

The presence of oceans or other large bodies The presence of oceans or other large bodies of water tend to moderate climatic conditions. of water tend to moderate climatic conditions.

The heating and cooling of the oceans are The heating and cooling of the oceans are major influences on climate and weather.major influences on climate and weather.

Water generally warms and cools more slowly Water generally warms and cools more slowly than land. Ocean temperatures drop more than land. Ocean temperatures drop more slowly with the approach of winter and warm slowly with the approach of winter and warm more slowly with the approach of summer more slowly with the approach of summer than landmasses. For example, it is usually than landmasses. For example, it is usually warmer near the shore on a winter day than warmer near the shore on a winter day than farther inland. Coastal areas generally have farther inland. Coastal areas generally have more moderate climates than interior areas at more moderate climates than interior areas at similar latitudes. similar latitudes.

Wind and ocean current Wind and ocean current

patternspatterns The temperature of ocean waterThe temperature of ocean water changes by changes by

location and by the location of major water location and by the location of major water current. current.

There are two important facts about water There are two important facts about water currents which influence the water currents which influence the water temperature;temperature; In the Northern Hemisphere, water currents In the Northern Hemisphere, water currents

move in a clockwise direction, in the Southern move in a clockwise direction, in the Southern Hemisphere, they move in an opposite Hemisphere, they move in an opposite direction.direction.

While the currents move westward along the While the currents move westward along the equator, they get warmer, come together at equator, they get warmer, come together at the equator, then when hit a landmass they the equator, then when hit a landmass they depart from each other.depart from each other.

E.g. Water is much colder in Los E.g. Water is much colder in Los Angeles than southern shores of Japan. Angeles than southern shores of Japan. The Caribbean Sea and the eastern The Caribbean Sea and the eastern coast of the US has warmer water than coast of the US has warmer water than Europe’s Atlantic beaches (at the same Europe’s Atlantic beaches (at the same latitude).latitude).

There are five major water currents;There are five major water currents; Gulf Stream (warm)Gulf Stream (warm) Japan Current (warm)Japan Current (warm) Humboldt (cold)Humboldt (cold) California (cold)California (cold) Benguela (cold)Benguela (cold)

Winds (weather patterns) also flow in Winds (weather patterns) also flow in currents (see page 5 of your course book).currents (see page 5 of your course book).

On the north and south of the tropics in the On the north and south of the tropics in the Northern and Southern Hemispheres Northern and Southern Hemispheres respectively, the wind currents move from respectively, the wind currents move from west to east (colder) “jet stream” E.g. from west to east (colder) “jet stream” E.g. from Istanbul to Ankara. (West is colder, e.g. Istanbul to Ankara. (West is colder, e.g. Iceland is warmer in winter than locations Iceland is warmer in winter than locations in Greenland and Canada on the same line in Greenland and Canada on the same line of latitude). However, in the tropics, they of latitude). However, in the tropics, they generally move from east to west (warmer) generally move from east to west (warmer) “trade winds”. “trade winds”.

Knowing which way the wind blows is Knowing which way the wind blows is important in determining the flying time. important in determining the flying time. E.g. Flying from San Francisco to Tokyo is E.g. Flying from San Francisco to Tokyo is longer than the other way round.longer than the other way round.

SeasonsSeasons The relative positions of the sun and the The relative positions of the sun and the

earth throughout the year determine the earth throughout the year determine the seasons. seasons.

The earthThe earth rotates around an imaginary rotates around an imaginary line passing through the poles, called line passing through the poles, called the the axisaxis. This line forms an angle . This line forms an angle (called (called the tilt) the tilt) of 23of 23,5,5° with the perpendicular ° with the perpendicular to the orbit of the Earth around the Sunto the orbit of the Earth around the Sun. .

Seasons are opposite in the Northern Seasons are opposite in the Northern and Southern Hemispheres.and Southern Hemispheres.

http://www.scienceu.com/observatory/articles/seasons/http://www.scienceu.com/observatory/articles/seasons/

seasons.htmlseasons.html

The seasons are then the result of this tilt of the The seasons are then the result of this tilt of the Earth's axis. Earth's axis. There are differences There are differences in how the in how the rays rays (sun light) (sun light) from the sun hit from the sun hit the earth the earth throughout the yearthroughout the year.. When When the rays coming the rays coming from from the sun is relatively direct, the weather the sun is relatively direct, the weather gets warmer and the days are longer. gets warmer and the days are longer.

Twice each year, approximately March 21 and Twice each year, approximately March 21 and September 21, the sun is directly overhead at September 21, the sun is directly overhead at noon on the equator. On these equinox dates, noon on the equator. On these equinox dates, virtually all points on the earth receive twelve virtually all points on the earth receive twelve hours of sunlight.hours of sunlight.

Twice each year, approximately June 21 and Twice each year, approximately June 21 and December 21, the difference between night and December 21, the difference between night and day is maximum. On these dates at noon, the day is maximum. On these dates at noon, the sun is at its most northerly or southerly position.sun is at its most northerly or southerly position.

Seasons at Northern and Southern Seasons at Northern and Southern HemispheresHemispheres

DateDate Northern Northern HemisphereHemisphere

Southern Southern HemisphereHemisphere

March 21March 21 SpringSpring AutumnAutumn

June 21June 21 SummerSummer WinterWinter

September 2September 233 AutumnAutumn SpringSpring

December December 2121 WinterWinter SummerSummer

Climates of the WorldClimates of the World

To identify climates according to To identify climates according to temperature and precipitation temperature and precipitation values, various attempts have been values, various attempts have been made. Koppen Classification System made. Koppen Classification System is the most accepted one.is the most accepted one.

The Koppen Classification System The Koppen Classification System has five basic climatic types.has five basic climatic types.

A - Tropical humid (tropical rain forest A - Tropical humid (tropical rain forest climates); monthly temperature is above climates); monthly temperature is above 18°C throughout the year. There is no real 18°C throughout the year. There is no real winter. Rainfall is high, precipitation winter. Rainfall is high, precipitation exceeds evaporation which produces lush exceeds evaporation which produces lush vegetation.vegetation.

B - Dry Climates (includes Desert Climate)B - Dry Climates (includes Desert Climate) C - Mild mid-latitude (includes C - Mild mid-latitude (includes

Mediterranean Climate); which have Mediterranean Climate); which have pronounced changes of seasons. The pronounced changes of seasons. The temperature in the coldest month is temperature in the coldest month is between 18°C and 0°C. between 18°C and 0°C.

D - Severe mid-latitude (Snow Climates); D - Severe mid-latitude (Snow Climates); which have average temperatures during which have average temperatures during the coldest month below 0°C and during the coldest month below 0°C and during the warmest month average 10°C.the warmest month average 10°C.

E - Polar (Ice Climates); which have no true E - Polar (Ice Climates); which have no true summer. Average temperatures during the summer. Average temperatures during the warmest month is below 10°C. warmest month is below 10°C.

http://www.eduplace.com/ss/maps/pdf/world_clim.pdfhttp://www.eduplace.com/ss/maps/pdf/world_clim.pdfhttp://geography.about.com/library/weekly/aa011700a.hhttp://geography.about.com/library/weekly/aa011700a.htmtmhttp://mediterraneangardensociety.org/climate/map.cfmhttp://mediterraneangardensociety.org/climate/map.cfmhttp://biology.about.com/library/weekly/aa012303a.htmhttp://biology.about.com/library/weekly/aa012303a.htmhttp://www.panda.org/news_facts/education/http://www.panda.org/news_facts/education/

virtual_wildlife/wild_places/tropical_forests.cfmvirtual_wildlife/wild_places/tropical_forests.cfmhttp://www.enchantedlearning.com/biomes/label/http://www.enchantedlearning.com/biomes/label/

desert/labelanswers.shtmldesert/labelanswers.shtml

Some Important Terms Some Important Terms

Referring climate and weather;Referring climate and weather; CycloneCyclone MonsoonsMonsoons

Referring to measurement of area, Referring to measurement of area, distance and temperature;distance and temperature;

Centigrade/FahrenheitCentigrade/Fahrenheit Hectare/AcreHectare/Acre Kilometer/MileKilometer/Mile Lapse RateLapse Rate

Centigrade/FahrenheitCentigrade/Fahrenheit

Celsius to FahrenheitCelsius to Fahrenheit

× 2 + 32× 2 + 32

Fahrenheit to CelsiusFahrenheit to Celsius

- 32 / 2- 32 / 2

http://www.cnn.com/weatherhttp://www.cnn.com/weather

Hectare/AcreHectare/Acre

Hectares to AcreHectares to Acre

× 2,47× 2,47

Acre to HectaresAcre to Hectares

× 0,4× 0,4

Kilometer/MileKilometer/Mile

Kilometers to MilesKilometers to Miles

× 0,6× 0,6

Miles to KilometersMiles to Kilometers

× 1,6× 1,6

http://goeurope.about.com/cs/maps/l/http://goeurope.about.com/cs/maps/l/bl_euro_dist.htmbl_euro_dist.htm