In this lab, I used ArcGIS to explore spatial map data of Canada and Washington State in the United States while learning about coordinate systems, datum’s, projections and vector and raster data models. Many different things can alter a map’s look such as distance, angle, area and direction and in order to prevent any possible distortion, we must make sure that all the data that is being downloaded and used are aligned to one another and are properly referenced to make further analysis and use of the map to be easier.

 

Coordinate Systems

Coordinate systems are one of the most important factors in GIS mapping as they determine the coordinates of places on Earth using longitude and latitude. In this lab, I had to fix misaligned data layers that were not referenced properly. This means that all the data that I was using did not have a common coordinate system which altered where each coordinate was in relation to one another.

In order to fix improperly referenced data in ArcGIS you can use the ArcToolbox Project command under Data Management Tools > Projections and Transformations where you insert the chosen dataset file and find the common projection for the output dataset. A new layer will be added to your map with a common projection relative to the other layers.

ArcGIS also has a feature called Projection-on-the-fly where layers are automatically aligned even when they are not in the same coordinate system to make viewing the map easier for your proposed audience.

Each project will be different with relation to the purpose of it and the data you will be using so it is very important that you check the coordinate systems of each layer by clicking on Properties in the drop-down menu of each layer to make sure that you will get the best representation of your map possible for your end result.

 

Landsat Data

Landsat is a remote sensing program that uses sunlight and infrared radiation as its energy source to measure and gather data for images of objects and surfaces on Earth. These images can be used to study a variety of topics such as vegetation or changes in coastal areas.

An advantage of Landsat images is that they provide repetitive observations of Earth since 1972 which allows analysts or scientists to compare the images from different time frames to study possible change that has occurred. Studying past change can help us determine environment patterns that might occur in the future to start planning mitigation effects. Landsat data is very crucial when it comes to human health, agriculture, climate, urban growth, forest management, natural disasters, ecosystems and biodiversity.