Mapping Informal Settlements in Developing Countries using Machine Learning and Low Resolution Multi-spectral Data

Informal settlements are home to the most socially and economically vulnerable people on the planet. In order to deliver effective economic and social aid, non-government organizations (NGOs), such as the United Nations Children's Fund (UNICEF), require detailed maps of the locations of informal settlements. However, data regarding informal and formal settlements is primarily unavailable and if available is often incomplete. This is due, in part, to the cost and complexity of gathering data on a large scale. To address these challenges, we, in this work, provide three contributions. 1) A brand new machine learning data-set, purposely developed for informal settlement detection. 2) We show that it is possible to detect informal settlements using freely available low-resolution (LR) data, in contrast to previous studies that use very-high resolution (VHR) satellite and aerial imagery, something that is cost-prohibitive for NGOs. 3) We demonstrate two effective classification schemes on our curated data set, one that is cost-efficient for NGOs and another that is cost-prohibitive for NGOs, but has additional utility. We integrate these schemes into a semi-automated pipeline that converts either a LR or VHR satellite image into a binary map that encodes the locations of informal settlements.Comment: Published at the AAAI/ACM Conference on AI, ethics and society. Extended results from our previous workshop: arXiv:1812.0081

Changes in croplands as a result of large scale mining and the associated impact on food security studied using timeseries Landsat images

Abstract: Geographic information systems and satellite remote sensing information are emerging technologies in land-cover change assessment. They now provide an opportunity to gain insights into land-cover change properties through the spatio-temporal data capture over several decades. The time series of Landsat images covering the 1985–2009 period is used here to explore the impacts of surface mining and reclamation, which constitute a dominant force in land-cover changes in the northwestern regions of the Czech Republic. Advanced quantification of the extent of mining activities is important for assessing how these land-cover changes affect ecosystem services such as croplands. The image

Soil classification using different spectroscopy data and chemometric methods

International audienc

Volcanic history of the Conchagua Peninsula (eastern El Salvador)

International audienceNew results of detailed geological mapping, K-Ar dating and geochemical study of the Conchagua Peninsula in eastern El Salvador are presented. Volcanism in the area was controlled by intersection of three tectonic structures, the trench-parallel Central Graben, perpendicular Comayagua Graben, and the Guayape Fault Zone. The age of the volcanic activity spans from Miocene to Quaternary, however, the volcano itself is extinct. The basement is built of the welded rhyolitic Playitas ignimbrite, which extends as far as to the Island of Zacatillo. The pyroclastic rocks of La Unión unit (mean K-Ar age: 13.3 ± 3.7 Ma) display signs of mingling between basaltic and dacitic magmas (banded pumice, deposits containing both mafic scoria and felsic pumice fragments), and this is interpreted as a result of eruptions triggered by injection of a basaltic magma into a dacitic magma chamber. Lavas and pyroclastic flow deposits of the subsequent Pozo unit are poorly exposed and strongly altered. Following effusive activity hereby defined as Pilón Lavas was dominated by andesite and basaltic andesite lavas. Pleistocene volcanic activity is represented by the Pre-Conchagua edifice (1.6 ± 0.6 Ma), Cerro Montoso, El Bable and Juana-Pancha. Regarding the trace element composition, some lavas of the Pre-Conchagua - Juana-Pancha are distinct from common volcanic front products (lower Zr/Nb, Th/Nb, Ba/Nb), resembling the lavas of Tegucigalpa volcanic field to the north, which is located behind the volcanic arc in the Comayagua Graben. Behind-arc extensional tectonics could have facilitated the magma genesis via decompression melting of the mantle wedge. The current Conchagua Volcano consists of two cones, Ocotal and Banderas, built by repeated Strombolian eruptions associated with effusions of basaltic lavas. The uppermost unit consists of a white tuff preserved in the sedimentary fill of several tectonic valleys west of Conchagua. The white tuff was interpreted as distal fall-out of the Tierra Blanca Joven eruption of the Ilopango Caldera