GIS questions

Please answer the questions from the word file. I have enclosed the lecture notes which should contain answers to the questions.

1.How do you calculate the area of “an object/set of objects” for a discrete thematic raster data set?

2. Describe the steps necessary for creating a raster (not vector) buffer data set.  How does buffering “objects” in a raster data set differ

fundamentally from buffering objects in a vector data set?  (Hint #1 is given in the question itself; hint #2 – think about the differences between raster and

vector data.)

3. Describe how raster overlaying works.  That is, what types of data is it typically applied to, what (Arc)GIS tools are used, and how are data in one layer

combined with data in another?  What challenge(s) can arise, and must be taken into consideration, when overlaying raster data sets?

4. What is a Boolean raster?  How do you create one?  Give an example of how/why you would use one or more Boolean rasters.

5. What are “zones” in zonal operations/analyses?  What two types of zonal statistics output can we create in ArcMap?  Provide an example of when/why we

might perform a zonal statistics analysis.

6. What is the difference between Euclidean distance and cost-distance analyses?  How does cost-distance analysis work?

7. What is the difference between profile and plan curvature measures?  What morphometric terrain characteristics can curvature measures be used to identify?

8. Briefly describe the steps for creating an elevation profile graph.  How/why might you want to use one?

9. How do flow direction and flow accumulation analyses work, in simple terms?  How do you know if a flow direction analysis has “gone wrong?”  What do the

values in a flow direction raster tell you?  In a flow accumulation raster?
10. What processing steps are necessary for delineating a watershed/set of watersheds?  Briefly describe each of these steps.

11. In his guest lecture, Dr. Ralph Haugerud (USGS/UW) described how LiDAR data are collected and processed, what they measure, and examples of their use.  One

prominent local application of LiDAR data has been measurement and evaluation of the Oso landslide complex in the North Fork Stillaguamish River valley.  Describe

how LiDAR data have been used to examine the location, both before and after the landslide.  What historic as well as recent geomorphic patterns and trends have

been measured and discovered through use of LiDAR data sets?