This map illustrates satellite-detected areas of potentially saturated soils and probable flood waters in the Jowhar, Middle Shabelle region of Somalia. Using satellite imagery acquired 30 October 2015 and 02 January 2015, UNITAR-UNOSAT identified a total affected area of roughly 54,000 hectares in the Shabelle Dhexe and Hoose provinces. As of 30 October 2015, approximately 41,500 hectares of possibly saturated wet soils, as well as about 12,200 hectares of probable standing flood waters were detected over the districts of Jowhar, Balcad and, Afgooye. Due to the low spatial resolution of satellite data used for this analysis, the exact limit of flood water is uncertain. Detected water bodies likely reflect an underestimation of all flood-affected areas within the map extent. This analysis has not yet been validated in the field. Please send ground feedback to UNITAR-UNOSAT.
UNOSAT datasets and maps are produced using a variety of methods. In general, analysts closely review satellite imagery, often comparing two or more images together, and determine notable changes between the images. For damage assessments, refugee or IDP assessments, and similar analyses, these changes are then manually documented in the vector data by the analyst. For flood extractions, landcover mapping and similar analyses, a variety of automated remote sensing techniques are used to extract the relevant information which is then reviewed and revised as necessary by the analyst. In all cases, resulting data is then loaded into a standardized UNOSAT geodatabase and exported asshapefiles for dissemination.
Caveats / Comments
This is a preliminary assessment and has not yet been validated in the field. It is important to consider the characteristics of the source imagery used in the analyses when interpreting results. For damage assessments it should be noted that only significant damage to the structural integrity of the buildings analyzed can be seen in imagery, while minor damage such as cracks or holes may not be visible at all. For flood extractions using radar data it is important to note that urban areas and highly vegetated areas may mask the flood signature and result in underestimation of flood waters. Users with specific questions or concerns should contact email@example.com to seek clarification.