Aim: How are meridians used to determine time zones? Do Now: Take out yesterday’s geographic coordinates work. Calculate the distance from NYC to Albany using the geographic coordinates in yesterday’s work.

Meridians (lines of Longitude)

Meridian An imaginary great circle on the earth's surface passing through the North and South geographic poles. All points on the same meridian have the same longitude. The highest point in the sky reached by the sun or another celestial body; a zenith. Noon or midday.

How do we use Earth’s rotation to measure time? The Mercator projection used here is one way of looking at the spherical earth as a flat map. Used since the 16th century for navigation, straight lines on this map can be used accurately as compass bearings but the size and shape of continents are distorted. 12/31/2018

What season was this picture taken? The Mercator projection used here is one way of looking at the spherical earth as a flat map. Used since the 16th century for navigation, straight lines on this map can be used accurately as compass bearings but the size and shape of continents are distorted. 12/31/2018

How do we know this is the summer? time? Summer solstice (06-21-11) World Sunlight Map @ 9PM EST

How do we use Earth’s rotation to measure time? Sun rises in the East and sets in the West. The Sunrise moves westward at a rate of 15° per hour (360° ÷ 24 hours) Standard Time Zones: 24 worldwide time zones, 15 ° of longitude apart. Time is measured from the Prime Meridian The date line is at the 180 meridian.

Vocabulary Time Zone: 24 worldwide time zones, 15 ° of longitude apart. West Prime Meridian East  Move time back Move time forward

Time Zones of the World

Are time zone lines always straight?

Time zones in the USA

Time Zones in the USA