GDO Interface – Additional functions (Drought Report)
Drought Module
This document shows some additional features of the GDO map viewer, focusing on the “Drought Impact Report”. For the basics of GDO, please refer to the main handbook, where the tutorials are listed.
Using the map viewer component of GDO, you can get additional insights on droughts for any point on the map.
Additional navigation features
Clicking the “Zoom to Country” button (Figure 1) will open a dropdown menu which shows all available countries in alphabetical order. Clicking on one will zoom the map view to your country of interest, highlighting it with a yellow outline.
Clicking the “Other Zooms” button (Figure 2) will present you additional options. If you click the “Go to Coordinates” option (b), you can enter decimal coordinates to find your study area on the map at the desired zoom level. The “Go to Town” button (a) allows you to enter the name of a settlement and select the desired one from a dropdown search result list. In both cases, the map will zoom to the area you searched for and highlight it on the map.
Identify Features
Using the “Identify Features” Button Figure 3, you can get additional information for any location on the map. For example, if you found an area on the map that you want to look into for more details, first click the button (1), then click the point on the map (2). This will open a report popup (Figure 4).
In this popup, you can extend four additional dropdown options. First is the “countries” tab. This will show information on which country the pixel you clicked on is located at. There are also numbers on Area in km² as well as a population figure. A link to the respective UN Human Development Report as well as a downloadable border vector file are also listed here.
The ”Administrative Reporting Units” tab breaks the area down to the administrative level. In our example (Figure 4), you can see that we clicked into Khorasan district, Iran. Again, there is a vector file available for download using the KML button.
The “Koppen Climate Classification” shows the climate zone of the clicked coordinates within the Köppen-Geiger climate zone scheme, including the code [1]. In this example, We clicked into an “Arid/Steppe/Cold” or “BSk” zone.
Finally, the “All Drought Indicators” tab lists all the most recent values of relevant drought indicators for the point you clicked, as well as their date of recording. For example, you can see that the clicked area has a precipitation surplus of 2.9 mm in this case (Figure 4).
Going back to the first tab (“countries”), you can see a blue “OPEN REPORT” button. Click it to reveal an extensive report on the location you clicked. It may take a while to load.
Drought Impact Report
A “Drought Impact Report” page will open, which lists extensive information on the clicked point. In this example, we clicked onto Saida, Algeria (Figure 5). At the top left, you can see the clicked coordinates. On the top righthand side, you can see a dropdown menu which allows you to show the report for a previous point in time. Below, you can see a localization map as well as some basic statistics on the selected country.
Scrolling down to directly below the country overview, you can extend an optional tab called “Extended info on country…”. This allows you to visualize a number of different country-specific parameters and their history (Figure 6).
Scrolling down further, you will next see the “Risk of Drought Impact for agriculture” tab. Here, statistics are listed on how much of the area of the selected administrative district is covered in which agricultural drought impact class by percentage as well as absolute area. Below, you can see a timeline of those parameters within the last year in form of a stacked bar chart (Figure 7). From this point, hovering over any chart within the drought report will show you a download button for the respective graph ().
Next up are precipitation statistics. Here, you can see two bar charts. The first one shows 10-day intervals of precipitation [mm] as bars in comparison with the long term average shown as a line, including a standard deviation region (Figure 8). You can change time-related parameters above the chart, such as start and end of period as well as data interval.
The second graph shows the cumulative deficit or surplus of the region within the specified timeframe compared to the long-term average. This graph can be used to more clearly visualize ongoing dry spells as well as their severity.
Next, you can find Standard Precipitation Index (SPI) time series (Figure 9). The SPI shows the standard deviation of the precipitation in comparison to the same time of year through the entire data timeline. The frame of reference is variable, for example SPI-3 covers a three month period in comparison to those three months in the long term average [2]. Again, you can change time parameters on the top, as well as select the reference window for the SPI time series on the right. The legend on the right allows for easier interpretation of the values.
Next are two sets of maps and bar charts. One on fAPAR (Fraction of Absorbed Photosynthetically Active Radiation) and one on soil moisture anomalies (Figure 10, Figure 11). Both feature a legend that helps you interpret the values and maps. The stacked bar chart below the map shows a time series of the last year for the respective parameter in relation to covered area by class, allowing for deeper insights into specific aspects of drought.
Finally, at the bottom of the report, you can find the climate zone split by affected area, as well as a split of the affected area by FAO land use class (Figure 12). Here, you can also look at different parameters in relation to their affected area class (e. g. “high” or “medium”). Options are diverse, with parameters such as population density and thermal regimes (Figure 12). This way, you can, for example, assess which livestock type is predominant within the highly affected area of the selected district for specialized insights or look at the share of large-scale irrigation to get insights on resilience.
References
[1] M. Kottek, J. Grieser, C. Beck, B. Rudolf, and F. Rubel, “World map of the Köppen-Geiger climate classification updated,” Meteorol. Z., vol. 15, no. 3, pp. 259–263, 2006.
[2] R. R. Heim, “A Review of Twentieth-Century Drought Indices Used in the United States,” Bull. Am. Meteorol. Soc., vol. 83, no. 8, pp. 1149–1166, Aug. 2002, doi: 10.1175/1520-0477-83.8.1149.