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  • Automated Mapping of Land Cover Type within International Heterogenous Landscapes Using Sentinel-2 Imagery with Ancillary Geospatial Data

    Abstract: A near-global framework for automated training data generation and land cover classification using shallow machine learning with low-density time series imagery does not exist. This study presents a methodology to map nine-class, six-class, and five-class land cover using two dates of a Sentinel-2 granule across seven international sites. The approach uses a series of spectral, textural, and distance decision functions combined with modified ancillary layers to create binary masks from which to generate a balanced set of training data applied to a random forest classifier. For the land cover masks, stepwise threshold adjustments were applied to reflectance, spectral index values, and Euclidean distance layers, with 62 combinations evaluated. Global and regional adaptive thresholds were computed. An annual 95th and 5th percentile NDVI composite was used to provide temporal corrections to the decision functions, and these corrections were compared against the original model. The accuracy assessment found that the regional adaptive thresholds for both the two-date land cover and the temporally corrected land cover could accurately map land cover type within nine-class, six-class, and five-class schemes. Lastly, the five-class and six-class models were compared with a manually labeled deep learning model (Esri), where they performed with similar accuracies. The results highlight performance in line with an intensive deep learning approach, and reasonably accurate models created without a full annual time series of imagery.
  • Pittsburgh District power team deploys in support of Tropical Storm Isaias response

    The U.S. Army Corps of Engineers Pittsburgh District’s temporary emergency power planning and response team deployed to Connecticut to provide generator power to critical facilities in the aftermath of Tropical Storm Isaias, Aug. 7. 
  • Army Corps, MDOT to host open house on Baltimore coastal storm study

    The U.S. Army Corps of Engineers, Baltimore District, and the Maryland Department of Transportation (MDOT) are holding an open house Sept. 23 from 6:30 p.m. to 8:30 p.m. at the Maryland Department of the Environment to provide information and seek input on a coastal storm risk management study for Baltimore.