Tag Archives: topographic_maps

Terrain Forms Lab

Following are pictures from the two sections of the Terrain Forms lab for FORT 130. We are very fortunate to have such an interesting landscape so close to the Mont Alto campus. I especially enjoyed coming up on the turkey vulture at the Clearcut site. It was hard to get a good picture of it.

Reading map coordinates

During yesterday’s lab we used the latitude/longitude ruler and UTM grid tool from Map Tools to find the coordinates of different features on the topographic maps. There are several ways you can improve the accuracy of your meaurements.

First, make sure the lines you drew on the map line up with the tick marks on the side of the map. The UTM ticks are inclined a bit from the main axis on the map (remember grid north) and it’s easy to get them off center. Strictly speaking you don’t need to draw lines on the map. You can get by with a long ruler in a pinch.

Know what the precision to which you are measuring. For example, the UTM grid is designed to read to 100 meter precision. Your answer should reflect that. With UTM we always read over and up, easting and northing.

The Lat/Long ruler has a 0.01minute side and a second side. Make sure you use the right one. since Longitudes increase from east to west in the western hemisphere we place the zero mark on the east guide line. I find it helps to frequently check that the zero and the 2.5 mark are lined up properly as I slide the ruler up and down the meridians.

Can anyone come up with other tips?

Folding Maps

Topographic maps in the field are bulky and cumbersome unless they are folded properly. Here are a few demonstrations of how to do it right to make the whole map accessible.

This is an online version of an army manual that gives several options for folding.

This method gives an accordion folded map along the long way.

This site shows the directions only, with no diagrams. It seems easy enough to follow.

Land Forms Lab Route

Here is a map of the route we followed for the land forms on topographic maps lab.

Reading Topographic Maps in the Field

Reading-topo.JPG

During yesterday’s field trip yesterday there was a bit of confusion over our location at the third stop. At first I thought we were on Shriners Knob. But when I checked the GPS waypoints back in the office it was obvious that we were on the side of Sandy Ridge. Congratulations to those of you who figured it out in the field!

The picture above is a screen shot from USA Photomaps, a program you will be learning shortly. It shows the data over a topographic map.

Here is link to the pictures I took georeferenced over a map in Flickr. Another view of the photos is available in Google Maps here.