ASSIGNMENT #1
This assignment is a small "mid-term" sanity check of your progress.
It is due by Monday Nov. 18 2019 - please upload in the link Assignment 1 hand-in
For those without laptops we can organize extra-time (OpenLab) in the computer room wednesday 6 November from 11 to 18 - please send me an email if you want to organize that. The computer room is booked for this so I just need to know how many people are interested.
- Styling raster and vector datasets loaded in QGIS
- Deal with different CRS
- Load point data from Text Files
- Sample raster values at points
- Download one or more Digital Elevation Model (DEM) tiles from SRTM 1-arcsecond products from anywhere in the world using the steps related to the chapter "USGS: EarthExplorer" in the handout - access geodata - v.2019_Oct19
- Load the raster tile in QGIS and style it with hillshade + color scale like in the first lecture - check tutorial Basic Raster Styling and Analysis (QGIS3)
- Load Google Earth Satellite Imagery using the QuickServices Plugin (if you do not remember how - check the chapter "TMS services" in the handout - access geodata - v.2019_Oct19
- Create your own table with 4 columns; ID, LAT, LON, water-table depth - you can use MS Excel , notepad, notepad++ or any other editor. PS water-depth is related to hypothetical water-table depth for your field (check https://water.usgs.gov/edu/graphics/wcgwstoragewell.gif )
- Add from 5 to 10 points, roughly around a 500x500 meter area, manually to the table with values that you decide (of course Latitude and longitude must be from the area - setup your QGIS view to show you latitude and longitude by project CRS settings as shown in handout handout CRS coordinate reference systems)
- import the points in QGIS (they should be overlapping your area if your LAT LON values were correctly determined in point 5)
- Provide a colorscale from white to red according to water-table depth values
- Digitize a polygon over the points simulating your area of interest (e.g. your study area)
- Apply a transparent fill to the polygon and a thick red border
- Find the
averageheight above sea level of your POINTS --> Sampling Raster Data using Points or Polygons (QGIS3) - Calculate distance of water-table to sea level (height of ground from point 10 minus depth of water-table e.g. if your point is 100 m a.s.l and your water table has depth = 10 m than 100 - 10 = 90 - use the field calculator to create a new column.( see https://docs.qgis.org/3.4/en/docs/user_manual/working_with_vector/field_calculator.html info on field calculator)
- Hand in (Assignment 1 hand-in ) a PDF map with TWO or more representations:
- your area, with points labelled with water-table depth and background of Google Satellite (see example in image at bottom of this page)
- your area with points labelled with water-table distance from sea level and Digital Elevation Model (DEM) raster as background.
For a tutorial on how to make maps follow the link Making a Map (QGIS3)
Below an example of how it could look - do your best, it does not have to be exactly the same but close (PS for adding "m" to the labels you have to create a concatenation of the label value with the string ' m' in the label options. We will see that in class, you do not have to have it in your map)