Exercise 2: Part 2: Calculate vulnerability index#

Aim of the exercise#

We want to create an overview of different vulnerability indicators. From the Covid-19 risk indicators dataset we take % permanent wall type, % permanent roof type and poverty incidence. From the Uganda population statistics we calculate the % of under fives and % of elderly. By combining the data, we are able to visualize the areas in Uganda that are most vulnerable.

Data#

Download all datasets and save the folder on your computer and unzip the file. The zip folder includes:

Hint

All files still have their original names. However, feel free to modify their names if necessary to identify them more easily.

Task#

This exercise aims to create an overview of the impact of disasters in various regions of Senegal using the prepared datasets from the previous exercise. To achieve this, non-spatial joins, table functions, and different symbology will be utilized.

  1. We will start by using the tool Join attributes by field value and join the population statistics onto the output from task 9 from the first part (uga_adm2_covid_risk) of the exercise.

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Fig. 175 Screenshot from the Join attribute by field value operation using the ADM2_PCODE for joining#

  1. For the following calculations, use the output layer from the previous operation and name it uga_adm2_covid_risk_pop. First, we will calculate the % of under fives. Open the Field calculator to calculate a new field of type decimal number:

%Under5 = ( "M_00" + "M_01" + "M_02" + "M_03" + "M_04" + "F_00" + "F_01" + "F_02" + "F_03" + "F_04" ) / "Total"

Hint

You can access the field calculator through your attribute table by activating Toggle editing mode and clicking on this symbol to Open field calculator.

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Fig. 176 Screenshot of the field calculator which will be used for the subsequent calculations#

  1. Open the Field calculator again to calculate another new field of type decimal number. This time, we will calculate the % of elderly, defined as those aged 65 and above.

%Above65 = ( "M_65" + "M_66" + "M_67" + "M_68" + "M_69" + "M_70" + "M_71" + "M_72" + "M_73" + "M_74" + "M_75" + "M_76" + "M_77" + "M_78" + "M_79" + "M_80plus" + "F_65" + "F_66" + "F_67" + "F_68" + "F_69" + "F_70" + "F_71" + "F_72" + "F_73" + "F_74" + "F_75" + "F_76" + "F_77" + "F_78" + "F_79" + "F_80plus" ) / "Total"

  1. Next, open the field calculator again to calculate a new field of type decimal number.

%Under5indicator = ( "%Under5" - minimum( "%Under5" )) / (maximum( "%Under5" ) - minimum( "%Under5" )) * 10

  1. Open the Field calculator to calculate a new field of type decimal number.

%Above65indicator = ( "%Above65" - minimum( "%Above65" )) / (maximum( "%Above65" ) - minimum( "%Above65" )) * 10

  1. Delete unnecessary fields from the attribute table.

  2. Again, open the Field calculator to calculate the average of vulnerabilities as the field type decimal number.

AvgVulnerability = ((10 - "%permrooft" ) + (10 - "%permwallt" ) + "Povertyinc" + "%Under5indicator" + "%Above65indicator" ) / 5

Now, you can save the changes and stop editing by clicking on this symbol .

  1. Change the symbology on the field AvgVulnerability to visualise the different vulnerabilities.

Hint

Use Graduated and select the correct field. Create a reasonable amount of classes and use the Equal Interval mode.

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Fig. 177 This is how your output could look like in the end#