Weather13.1 & 13.3 A Closer Look at the Earth and Why we have

Seasons

http://youtube.com/watch?v=s76Qn7bpCsQ&feature=related

BLM 13.1AQuick Review Question Sheet

Weather and Climate (Q3)

• Weather… What is It?– Day to day environmental conditions

• Examples: – Rainy / snowy– cloudy / sunny– Windy / calm

• Climate– Environmental condition averaged over many

years• Examples:

– Average rainfall– Average daily temperature

Weather and Climate

• Variable used to describe weather and climate:– Temperature– Wind Speed and Direction– Visibility– Cloud cover– Atmospheric Pressure– Dew Point– Humidity

Formation of Weather and Climate

Now some questions for you to think about… I’ll read the question to you and then ask you what the first thing is you think about…

1. Now that you know what weather is can you tell me if the weather is the same here as it is in St. John? Why not?

2. Geographically, how is St.John different than Fredericton?3. Would any of these geographical features affect the weather in that area? If so which

ones and how?

Good Discussion! Here are the facts:

Components that influence weather and climate include:• Latitude and Longitude• Atmosphere• Oceans• Land Masses

Influences on Weather and Climate and Latitude/Longitude

(Q1)• Components that influence

weather and climate include:• Latitude and Longitude• Atmosphere (later)• Oceans(later)• Land Masses(later)

– This Video (10 min) will get you started on Lat. And Long.!!

– More information to come :>

Lat & Long

Longitude (Meridians) (Q4)

• Angle of measure east or west of the Prime Meridian

• Imaginary vertical lines

Label on Your Map• Prime Meridian 0o

(Greenwich, England)• International Dateline 180o

Latitude (Parallels) (Q5,6,7)

• Angle of measure north or south of the Equator• Imaginary horizontal lines

Label on Your Map:(BLM 13.1A)

• Equator 0o

• North Pole 90oN • South Pole 90oS• Arctic Circle 67.5oN• Antarctic Circle 67.5oS• Tropic of Cancer 23.5oN• Tropic of Capricorn 23.5oS

Earth’s Rotation and Revolution• Rotation (24 hours)

– The Earth rotates on its axis– The axis (imaginary line) runs North to South

• 23.5o angle– One Earth rotation takes one day

• Rotate East to West• Revolution (365 Days)

– The Earth revolves around the Sun• The movement of one object traveling

around another– It takes the earth one year to revolve (travel)

around the Sun counter clockwiseAny ideas as to how earth’s tilt towards or away

from the sun can effect the 4 season’s we experience here in Canada??

Reason for the Seasons

• The average tilt, 23.5o, of the Earth is the reason for the seasons)

• As the Earth revolves around the Sun, the seasons in the northern and southern hemispheres are opposite.

http://geovideos.fliggo.com/video/NY5Lxu6q

I. Tilt of the Earth’s axis towards or away from the sun creates the seasons

Earth’s Seasons

North Pole

Earth

When the north pole tilts toward thesun, it gets more radiation – more warmth

during the summer

SUMMER (Northern Hemisphere)

South Pole

WINTER (Southern Hemisphere)

When the north pole tilts toward thesun, the south pole tilts away

So when it’s summer in the north, it’s winter in the south

Equator

I. Tilt of the Earth’s axis towards or away from the sun creates the seasons

Earth’s Seasons

When the north pole tilts away from the sun, it gets less radiation –

So it’s colder during the winter

North Pole

Earth

WINTER (Northern Hemisphere)

South Pole

SUMMER (Southern Hemisphere)

When the north pole tilts away from thesun, the south pole tilts toward it…

When it’s winter in the north, it’s summer in the south

Equator

Bill Nye: Seasons

• Handout: Seasons Worksheet (24 min)

• https://secure.e-registernow.com/cgi-bin/portal.cgi?state=210

1. Why is the tilt of the earth the cause for the seasons?A. Seasons are not connected to Earth's distance from the Sun - our

northern winter takes place when the Earth is actually closest to the Sun - but due to the fact that the Earth's axis is tilted away perpendicular to the ecliptic, winter takes place.

• The greater the angle, the less energy transferred.

Reason for the Season: The Earth’s Tilt

Q2. The North pole and South Pole each have long periods of complete sunlight and complete darkness. Why?

A. When the Earth is tilted away from the Sun, the North Pole has no Sun for about 6 months. During the same time, the South Pole is pointed toward the Sun and receives nothing but Sun.

NEXT… What is wind? And how is it formed…

Reason for the Season: The Earth’s Tilt

Mapping Activity

• Short Worksheet – – Part A: students to determine latitude and

longitude of a location– Part B: students to determine location based on

latitude and longitude.