Selection of 1916 Use District Map Section No. 10. New York (N.Y.). Board of Estimate and Apportionment (Author). Lionel Pincus and Princess Firyal Map Division, The New York Public Library.
QGIS and Symbology
In this activity, we will add some point and polygon layers and explore the symbology features of QGIS. We will work with ZIP archives of shapefiles, and also with sets of associated files that together comprise what we often call a ‘shapefile’. Shapefiles are associated files that each help create a vector file in QGIS (or ArcGIS, where shapefiles originated).
We will revisit connecting an ArcGIS REST Service (a kind of Web-based Map Server) layer to our QGIS. We will display a layer made available by the Montgomery County, Pennsylvania Data and Mapping Services office through their county-level clearinghouse or “open data portal”. https://data-montcopa.opendata.arcgis.com/.
We will also learn how to select features from an attribute table by building a very simple expression. From there, we will clip just those records within an attribute table that we want, and we will save our own derived vector file(s). This practice of accessing large geospatial datasets and selecting only the records or features needed then saving them, is a process you will likely repeat many times throughout this course. It is important that we are systematic in how we name our files and where we store them. Carefully recording, or citing the sources of our data and how they are derived is an essential research and scholarly practice. We will cover in class how QGIS can assist us in recording where our data originates, and how we transform it for our specific needs and purposes.
Below is a link to the instructions for tonight’s activity:
https://docs.google.com/document/d/1fhtDFy_GiX7WAmWiNlMeVdXaw1HvgPOKWC3yKuDxEPY/edit?usp=sharing
The two ZIP files containing point layers for Ward 1 of North Wales Borough are available here:
https://drive.google.com/drive/folders/1VInFWhK4QwBEDTe4SsKNUIjHF2VOvpQ_?usp=sharing
The Power of Maps
If you have been following the terrible news from Morocco over the weekend, you aren’t alone. A very powerful earthquake struck Morocco Friday (9/8) evening, and the scope of the damage and loss of life is still not known. Rescues and responses to humanitarian needs are underway now. The New York Times has prepared a series of maps to convey the power of this earthquake, the scope of its impacts, and the known history of earthquakes across this region of the world. Please take a moment to consider not only the contents of this important news story, but also the craft, sophistication, and power of the maps contained within it. GIS and related digital mapping technologies allow us to build thematic maps more quickly and more accurately than ever before. The density of information within these few maps is remarkable. The power of maps to inform, to connect us to those suffering from this tragedy, and to aid those responding to this crisis, is something we can all access and leverage, ourselves, through the technologies we study together in this course. Click on the link below to read more.
https://www.nytimes.com/interactive/2023/09/09/world/africa/morocco-earthquake-damage.html
Our thoughts are with the people of Morocco.