Welcome to Earth Science 2017-2018

Mapping our World Chapter 2

EES News and Notes If you are not doing so hot, remember to come visit me today or tomorrow during lunch time to learn how to improve your grade. This is MANDATORY if you are currently below a 70% in class. We’ll practice a bit more conversion work today Then, we’ll get a chance to do some group work on our various projects We’ll end today by taking notes in the new section of material, Chapter 2

The Science of Map Making Cartography: The science of mapmaking. Cartographers use an imaginary grid of parallel lines and vertical lines to locate exact points on the Earth.

Equator Equator: imaginary line that circles Earth halfway between the north and south poles. The equator separates Earth into equal halves called north and south hemispheres.

Latitude Latitude: lines running parallel to the equator. Latitude = distance of degrees north or south of the equator. The equator is a reference point numbered at zero degrees (0°) latitude. Latitude starts at 0° latitude and runs to 90° latitude at the poles.

Degrees of Latitude Each degree of latitude is equivalent to about 111 km (68.9 miles) on the Earth’s surface How did cartographers (map makers) decide this? Earth is a sphere = 360° Earth’s circumference = 40,000 km 40,000 / 360° = 111 km/degree

Latitude Cartographers can also get more precise by breaking down degrees of latitude into 60 smaller units, called ‘minutes.’ The symbol for minutes: ’ Each minute (’) of latitude is 1.85 km To get more precise, you can break down latitude into seconds (”).

Bell Ringer – Half Sheet of Paper How many grams of sand are there in a 12.47 kg bag of sand? What is the invisible line called that represents 0° Latitude separating the north and south hemispheres? What is the main problem with describing coordinates with only degrees and not minutes or seconds?

EES News and Notes If you are not doing so hot, remember to come visit me today during lunch time to learn how to improve your grade. This is MANDATORY if you are currently below a 70% in class. We’ll get a chance to do some group work on our various projects We’ll end today by taking notes in the new section of material, Chapter 2 We’ll practice a bit more conversion work today

Longitude Longitude: Locating positions in east and west directions, also known as meridians. Prime Meridian: Reference point for longitude. Equal to 0° longitude Crosses through Greenwich, England Points west of the prime meridian are numbered 0° to 180° west (W) longitude Points east of the prime meridian are numbered 0° to 180° east (E) longitude

Stop and Think What are some of the main differences that you see between the way that latitude is divided versus longitude? Latitude = Parallel Longitude = start and stop at same point; orange slices

Latitude vs Longitude

Semicircles Unlike lines of latitude, lines of longitude are not parallel. They are large semicircles that extend vertically from pole to pole. Both latitude and longitude are needed to precisely locate a point on the Earth.

Degrees of Latitude vs. Longitude Degrees of latitude cover roughly the same distances everywhere. Degrees of longitude vary with location. A degree of longitude will be as large as 111 km at the equator A degree of longitude will be closer to 0 km at the north pole or south pole

Using Coordinates For a precise location, we need to use both degrees of latitude and degrees of longitude. What’s wrong with saying that Charlotte, NC is along the 35°14’N line of north latitude? What’s wrong with saying that Charlotte is along the 80°15’ W line of longitude? Charlotte is located at 35°14’N 80°15’ W.

Time Zones Earth is divided into 24 time zones. Why do you think this is? It takes the Earth 24 hours to rotate on its axis! This explains why there are 24 time zones. Each time zone is 15° wide, roughly two lines of longitude.

Time Zones

International Date Line Each time you travel through a time zone, you gain or lose time until you gain or lose an entire day. International Date Line: 180° meridian, serves as the transition line for calendar days. Imaginary line runs through the Pacific Ocean. Traveling west: lose a day Traveling east: gain a day

Let’s See it in Practice Today is Monday, September 25. If you are travelling across the international date line headed east, it would still be Sunday, September 24. If you were travelling across the international date line headed west, it will be Monday, September 25 or Tuesday, September 26, depending on the time of day you crossed it!