the Hurricane Katrina Project GIS2 Lab 5 (Part 1 of 3)

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This GIS project offers you a complete hands-on learning experience. It exposes you to the entire workflow that a seasoned GIS Analyst, a GISCorps volunteer, or a Humanitarian OSM team member will use during the days following a major disaster. The project starts with a question, which is broken down into clear objectives, and it ends with an evidence-supported answer. This particular workflow requires you to obtain data from trusted data providers and to prepare them for spatial analysis. Some data will come as tables, some as rasters, and some as vectors. This GIS project also offers you opportunities to visualize the destructive storm surge and to assess Hurricane Katrina’s destructive power using Esri’s ArcGIS Desktop v.10.4.1.

A research question is an interesting question – it identifies what we really want to know and helps us to set the purpose of the entire project (i.e., to answer the question).

How did Hurricane Katrina affect people and property along Mississippi’s Gulf Coast?

Objectives identify the pieces of information we need to collect, build, calculate, etc., in order to answer the question. This project has nine objectives:

1. To describe the resident population before, after, and since the storm. 2. To describe the workforce before, after, and since the storm. 3. To report the size of the study area, in km2 (mi2). 4. To describe the site and situation of the study area (see Rodrigue, 2014, or Elrod, 2014, if

you need a refresher on these basic geography concepts). 5. To estimate the height of the highest storm surge, in m (ft). 6. To estimate how much land area was flooded by the storm surge, in km2 (mi2). 7. To describe in words and to illustrate with maps the geospatial distributions of flooded

areas and destroyed areas. 8. To find destroyed roads and estimate the total cost of rebuilding them.

Figure 1. A home destroyed by the storm.

The region affected by Hurricane Katrina is vast, so we are going to use a representative sample area to represent the whole area. The sample area will be the populated place known as Long Beach city, which is situated in Mississippi’s Harrison County and at the center of its Gulf Coast.

the Hurricane Katrina Project GIS2 Lab 5 (Part 1 of 3)

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We cannot go back in time and re-experience the disaster, but we can gather historical data, build a GIS to analyze pre- and post-storm conditions, and discover information useful for answering the research question. So, for Lab 05, I want to help you to: a) obtain “raw” data (geospatial and tabular) from trusted data providers; b) prepare those data for analysis; and c) see the big picture. Advice: I recommend printing this handout and taking notes on it as you work. Write down the name of each file you download, what it represents, and from where it came. You will come to rely on your notes as you take breaks. Importantly, read everything before doing anything so you can visualize your workflow and anticipate what comes next. Task 1: Prepare a workspace for the project Create a new folder for the Hurricane Katrina project. In it, create: a) a subfolder called “zipped” to store any raw data (i.e., anything you download); and b) a new file geodatabase to store all of your geoprocessed data. Name your geodatabase katrina_<your initials here>.gdb Task 2: Choose an appropriate spatial reference system. Our analysis requires us to calculate areas and distances from our data. Fortunately, our study area fits completely within one of Mississippi’s two mapping zones. We’ll use the metric

(NAD83) State Plane Mississippi East spatial reference system (SPC MS-E; see Lab 4 and Bolstad, 2016: p126) to support our work. Geospatial data representing entities (via vectors) or fields (via rasters) in Mississippi’s eastern zone will contain negligible distortions after they are projected onto this spatial reference system. Task 3: Visit trusted data providers and select relevant data (Bolstad, Chap. 7) Economic data from the US Census Bureau

http://onthemap.ces.census.gov/

The US Census Bureau’s OnTheMap application (link above) can be used to collect jobs data for working people that worked in Long Beach during the years 2005, 2006 and 2014.

A. Start by searching among Places for a place called Long Beach; click the result that will refocus the map on Long Beach city, MS.

B. When prompted, follow the link to Perform Analysis on the Selection Area: a. Home/Work area: Work b. Analysis Type: Area profile with the Labor Market Segment: All workers c. Years: 2005, 2006, and 2014 d. Job type: All jobs e. [GO!]

i. After results appear, use the left-side menu to make a Detailed Report, which you can export to Microsoft Excel ® format for later use.

the Hurricane Katrina Project GIS2 Lab 5 (Part 1 of 3)

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Population data from the US Census Bureau

http://factfinder2.census.gov/faces/nav/jsf/pages/index.xhtml

We need accurate population data representing all the people that lived in Long Beach. So, we’ll use the US Census Bureau’s American Factfinder website (link above) to access age-sex data for Long Beach, Mississippi, for the census years 2000 and 2010. Follow these instructions …

► Advanced Search -> [SHOW ME ALL] A. Geographies -> Select Geographies List -> Place -> Mississippi -> Long Beach city,

Mississippi -> [Add to your selections] -> then [Close X] the Select Geographies window.

For census year 2000 B. Topics -> [+] Dataset -> 2000 SF1 100% data -> then [Close X] the Select Topics window.

C. In the Search Results window -> search for and select :

QT-P1: Age Groups and Sex: 2000 -> View

Download the 2000 table (Microsoft Excel ® format) to your ‘zipped’ folder.

For census year 2010 D. If you opened the table View, then you’ll have the option to toggle between the 2000 and

2010 versions of this table. Toggle to 2010. (If you did not open the table View, then return to steps B and C and substitute year 2010 for year 2000.)

Download the 2010 table (Microsoft Excel ® format) to your ‘zipped’ folder.

Polygon boundary data from the US Census Bureau

https://www.census.gov/geo/maps-data/data/tiger-cart-boundary.html

We need polygon data to represent the study area. So, use another US Census Bureau website (link above) to download the 2015-vintage (latest available) 1:500,000 scale shapefiles for State (nation-based files) and for Place (state-based files).

Task 4: Preparing your vector data for later analysis (via ArcCatalog ) After unzipping both the Places and States ZIP archives, use ArcCatalog to Export only the Mississippi state polygon (SQL expression: “NAME” = ‘Mississippi’) into your geodatabase. Next, Export only the Long Beach place polygon (SQL expression: “NAME” = ‘Long Beach’) to your geodatabase. Question 1a: Preview the attribute table of your geographic Long Beach polygon. What is the value stored in the Shape_Area field? Project each polygon onto the SPC MS-E coordinate system. Question 1b: Preview the attribute table of your projected Long Beach polygon. What is the value stored in the Shape_Area field? In sq.km (and sq.mi)?

the Hurricane Katrina Project GIS2 Lab 5 (Part 1 of 3)

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Rasters from the USDA GeoSpatialDataGateway

https://gdg.sc.egov.usda.gov/

Last but not least, we need a high quality DEM to represent ground surface topography and we need an orthophoto that represents on-the-ground conditions just prior to the hurricane. The US Department of Agriculture is an authorized distributor of the National Elevation Dataset (Bolstad, 2016: p305-307) and the national mosaic of NAIP imagery (p311-313). The USDA’s GeoSpatialDataGateway is relatively easy to use, but you do have to look around for the right buttons. To place an order, follow these steps:

Start by clicking the big Get Data button to enter the GeoSpatialDataGateway.

1. Where:

a. Change the method for selecting the order area to Order by Bounding Rectangle, and use these bounding coordinates listed below, which describe an area that is slightly larger than the area covered by your Long Beach polygon:

i. West, 89.2040˚ W; East, 89.1240˚ W

ii. North: 30.3840˚ N; South: 30.3310˚ N

iii. Check Desired Coordinates; if the red polygon looks good, then Submit

Desired Coordinates.

2. What:

☒ National Elevation Dataset 3 m (i.e., our national DEM with a 3-m cell size)

☒ 2004 National Ag. Imagery Program (NAIP) Mosaic

[Continue]

3. How:

a. Set the INCLUSION type to Extract by clicking the [HERE] button. (I know, this is a strange way to “clip our data using your bounding rectangle”.)

b. Check to ensure the DELIVERY type is still set to FTP.

[Continue]

4. Who:

The USDA keeps track of who uses the GeoSpatialDataGateway, so you need to fill the required fields (*) and, most importantly, to provide a working email address.

[Continue]

5. Review:

If your order looks good, then [Place Order]. Orders can take several minutes or several hours to process, depending on how many people are on the system.

Finished

the Hurricane Katrina Project GIS2 Lab 5 (Part 1 of 3)

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And a report from the National Oceanic and Atmospheric Administration http://www1.ncdc.noaa.gov/pub/data/techrpts/tr200501/tech-report-200501z.pdf

The NOAA National Climatic Data Center has summarized what went on during Hurricane Katrina. Download and review the report, particularly the sections pertaining to Mississippi.

http://storms.ngs.noaa.gov/katrina/

We need digital aerial photography that represents on-the-ground conditions immediately after the storm. NOAA contractors flew aerial reconnaissance missions immediately after the storm and raw images online (link above). Unfortunately, this NOAA website is not user friendly, so I collected the right subset of NOAA images and will give them to you with Lab 6. Question 2: Build a table that presents the name of each geospatial dataset that you downloaded and the spatial reference system associated with it [i.e., a- earth model, b- datum/GCS, c- map projection class (if any), d- planar coordinate system name (if any), and e- the unit of measure for the coordinates]. Be sure to number your table, include a useful caption, and refer to the table by number when you answer this question (see Table 1 for an example).

Task 4: Preparing your geospatial data for analysis (via ArcCatalog ) I very strongly recommend doing all of your work in ArcCatalog. Yes, you can access the ArcCatalog and ArcToolbox windows via ArcMap, but ArcMap’s auto-display feature makes this part very confusing for people learning GIS. ArcCatalog is your friend. You should NOT use ArcMap for any part of this lab.

The US Census Bureau, USDA, and USGS distribute data with helper files (*.prj, *.xml) that define the spatial reference systems or contain metadata. ArcGIS can read these helper files, which is great, because you can simply Project vector vertices and Project Raster cells from their “input” spatial reference systems onto the desired ‘SPC Mississippi-E’ referencing system (see Task 2).

When projecting your USGS NED raster onto the SPC Mississippi E system, specify a 3-m output cell size. When projecting the USDA NAIP extract, specify a 1-m output cell size. Use bilinear resampling (p.162) for both rasters; and project each raster as a whole (do not project each NAIP image band individually; do project the composite as a whole). Figure 2 illustrates the spatial logic to follow when projecting or re-projecting geospatial data. Task 5: Answering more questions Question 3: According the Census Bureau’s metadata or its online glossary, what is an “incorporated place”?

the Hurricane Katrina Project GIS2 Lab 5 (Part 1 of 3)

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Question 4: Use the NOAA report to find: a. the amount of rainfall observed at the HANCOCK rain station, then report it in both cm

(and inches); b. the strongest wind gust at KEESLER Air Force Base, and report it in both km/hr (and

miles/hr); and c. the maximum stream stage and the base level at the USGS river gauge at WORTHAM,

MS, then report the difference between base level and stream stage in both m (and ft). Question 5: According to our US Census, how many people lived in Long Beach, MS, in 2000, before Hurricane Katrina landed; and how many lived there afterwards, in 2010? Report the amount of change (+/- #) and the percent change (see Equation 1) for the period.

%𝑐ℎ𝑎𝑛𝑔𝑒 =𝑣𝑎𝑙𝑢𝑒𝑡2−𝑣𝑎𝑙𝑢𝑒𝑡1

𝑣𝑎𝑙𝑢𝑒𝑡1× 100 Eq. 1

Where: 𝑣𝑎𝑙𝑢𝑒𝑡1 is the value measured at time 1 and 𝑣𝑎𝑙𝑢𝑒𝑡2 is the value observed at time 2. Question 6: Use the Microsoft Excel ® workbook I provided to help you build graphs that illustrate the 2000- and 2010-vintage population structures for the study area. In your report, be sure to number each figure, give each a useful caption (see Figure 2 for an example), and refer to each figure by number as you describe the cohort(s) that changed the most. Question 7: How many working people lived in Long Beach, MS, before Hurricane Katrina (June 2005), after Hurricane Katrina (June 2006) and since (June 2014)? Calculate percent changes (see Eq. 1), then describe any substantial changes (+/- #) – not all changes. Feel free to focus on the age groups, earnings groups, or the industry sectors.

Table 1: Population counts and rates of change, by group, for Census Tract 22 in Harrison County, MS (Source: US Census Bureau, 2010).

Group Count %Change

C #### %%% B ### %%% A D

## #

%% %%

Other # %

Total: #

Turn your data into information by sorting your table. Table records can be sorted by a numeric field – either in ascending or descending order – whichever helps you highlight the largest values or the biggest changes.

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Build a well-written report for Lab 05. Include your name, date, lab title, and page numbers. Your report should be printed on 8.5” by 11” stock. Set all page margins to be 0.7”, except for the left margin, which should be set to 1.2”. Use 1.5 line spacing, set the normal font face to be Bookman Antiqua, Bookman Old Style, or Georgia (hey, a southern project deserves a font with a southern name), and set the normal font size to be 11 points. All section headings should be in bold face. Neither headings nor captions should not be orphaned.

Your report should include five sections with headings: Purpose, Objectives, Methods and Data, Results and Answers, and Summary. Your Purpose and Objectives sections should be written in your own words and must address the specific purpose and specific objectives of only Lab 05 (and not the purpose or objectives of the entire research project).

Your Methods and Data section will be short this time. Simply include a table that is organized by data provider and lists every dataset you obtained. In the third column, indicate whether you needed to use the Project tool (P) or the Project Raster tool (PR) to project/re-project the data.

Table 2: Data obtained, by data provider. The codes ‘P’ and ‘PR’ indicate the Project tool and the Project Raster tool, respectively.

Data provider Dataset GIS Tool

Provider X Dataset X1 - Dataset X2 P Provider Y Dataset Y1 PR

# The Results and Answers section should include answers to the questions posed during

the lab as well as any evidence or supporting tables or figures. Always report units of measure. In your Summary, discuss what you learned about the disaster and/or about GIS, and

describe any “light bulb” moments that occurred as you worked. Note: All tables and figures must be numbered, have captions, and be referenced in your

text. Table and figure captions should not be orphaned and, when appropriate, identify units of measure. All tables and figures must be inserted inline with your text (add an extra line space before and after each to buffer them away from adjacent paragraphs) and conform to the margin and font requirements specified above. You want your report to look professional; applying a consistent design and style throughout is an effective way to do that.

Elrod, Z (2014) Site and Situation review. Accessed on August 12, 2015 at https://www.youtube.com/watch?v=f3on9hVWJkI

Rodrigue, R-P (2014) The Geography of Transport Systems: Site and Situation. Accessed on April 2, 2014 at http://people.hofstra.edu/geotrans/eng/ch1en/conc1en/sitesituation.html

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Figure 2. The GIS workflow that ensures your geospatial data are plotted on your desired spatial reference system before conducting any analysis.

RAW DATA PROPERTIES

(vector or raster)

Does ArcGIS recognize the input spatial

reference system?

ArcToolbox DEFINE PROJECTION

ArcToolbox PROJECT

NO, it says “UNKNOWN”

YES, it is DEFINED. I can see its name and all the details in the Properties.

ArcToolbox PROJECT RASTER

Vector

OR

Raster

VECTOR DATA

Ready for analysis

RASTER DATA

Ready for analysis

if RASTER

if VECTOR

Data with a DEFINED spatial ref. system

ArcCatalog Properties:

XY Coordinate System

ArcCatalog

OR

ArcToolbox

if CA

TA

LO

G

if TOOLBOX

You shouldn’t have to worry about this part of the flow chart, for all your data should come with known and defined spatial reference system information.

NED: 3-meter cell size. NAIP image: 1-meter cell size Use bilinear resampling with both.