Deciphering climate-induced displacement in Somalia: A remote sensing perspective

Remote sensing data Sentinel-1. Sentinel-1 offers an open-source Synthetic Aperture Radar (SAR) imaging sat- ellite data with medium spatial resolution as part of the European Space Agency Copernicus programme. Sentinel-1 comprises of two satellites launched on 3 April 2014 and 22 April 2016. The SAR system operates within C-band (5.407 GHz) frequencies in one of four acquisi- tion modes, with the default mode being Interferometric Wide Swath on land. In total, we downloaded and processed 32 SENTINEL-1 GRD scenes (16 pairs) from the Alaska Satellite Facility (ASF), spanning from 07/01/2016 to 30/10/2019. We used the Sentinel-1 satellite data to map the flood events in Somalia. Fig 4 shows Sentinel-1 acquired on 30th May 2016 during a flood event affected Beledweyne city. The areas near riverbank with black colour represent as the flooded zones where there are low backscatter. Furthermore, it has been observed that sandy areas located further from the river exhibit a similar low backscatter to the flooded areas and also represented in black. Sentinel-2. The Sentinel-2 (Sentinel-2) dataset is an open-source optical with medium to high spatial resolution satellite data provided as a part of the ESA Copernicus programme. The S-2 mission consists of two satellites: Sentinel-2A and Sentinel-2B. Sentinel-2 provides multi- spectral data with 13 bands in the visible, near-infrared, and short-wave infrared parts of the spectrum. The S-2 is equipped with the state-of-the-art Multispectral Instrument, offering

Table 1. List of districts used as areas of interest (AOI) for agricultural drought indicator. NO Districts District Area (km2) NO Districts District Area (km2) 1 Saakow 6774 9 Bulo Burto 16054 2 Jowhar 4637 10 Baardheere 15275 3 Balcad 4238 11 Jalalaqsi 3123 4 Jalalqsi 3123 12 Kurtunwaarey 2546 5 Luuq 8260 13 Qansax Dheere 3267 6 Belet Weyne 14867 14 Rab Dhuure 3309 7 Bulo Burto 16054 15 Tayeeglow 6596 8 Garbahaarey 8318 16 Doolow 1618 https://doi.org/10.1371/journal.pone.0304202.t001 Fig 4. Sentinel-1 imagery acquired over Belet Weyne city in Somalia on 30th May 2016. https://doi.org/10.1371/journal.pone.0304202.g004 PLOS ONE Deciphering Climate-induced Displacement in Somalia: A Remote Sensing Perspective PLOS ONE | https://doi.org/10.1371/journal.pone.0304202 August 9, 2024 6 / 27