USDA/NASS Disaster Analysis Web Page
https://www.nass.usda.gov/Research_and_Science/Disaster-Analysis/index.php

Synopsis
Event: Hurricane Laura

Last Updated: September 14, 2020

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File: Hurricane_Laura_Inundation_Layer.zip

Description: This dataset is a 2020 inundation raster layer created to 
estimate the extent of cropland and pasture/hay inundated by flooding 
from Hurricane Laura. The study area includes Louisiana, Arkansas, and
Mississippi, United States of America. Data represent cropland,
inundated cropland, pasture/hay, inundated pasture/hay, 
water bodies, and other land.

Projection: Albers Conical Equal Area

Spatial Resolution: 30 meter

Attribute Table

Value	Class_Name
1	Water
2	Other
10	Cropland
11	Inundated Cropland
20	Pasture Hay
21	Inundated Pasture Hay

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Imagery Inputs

Sentinel-1A Data: Interferometric Wide (IW) swath (250 kilometer),
Level-1 Ground Range Detected (GRD), 5x20 meter spatial resolution, and 
dual polarization (VV, VH)

Pre-Flood Sentinel 1A Imagery: 8/15, 8/16, 8/20, 8/22

Post-Flood Sentinel 1A Imagery: 9/1, 9/2, 9/3, 9/4
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Land Cover Inputs

NASS 2019 Cultivated Layer (planted acres)
Obtained From: https://www.nass.usda.gov/Research_and_Science/Cropland/Release/index.php

NASS 2019 Cropland Data Layer (planted acres)
Obtained From: CropScape: https://nassgeodata.gmu.edu/CropScape/

Disclaimer: These data are not official NASS estimates. 

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Processing Software

The Hurricane Laura inundation data layer was created within Google Earth Engine (GEE). The
use of GEE was a proof of concept for a modified processing methodology.

Hexagon ERDAS Imagine 2018 (used for post-processing of raster data and acreage tabulation)
http://www.hexagongeospatial.com/

Esri ArcGIS 10.7.0 (used for processing of vector data and for mapping and graphics)
http://www.esri.com/

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Methodology

Boryan, C., Z. Yang, A. Sandborn, P. Willis, and B. Haack (2018). 
Operational Agricultural Flood Monitoring With Sentinel-1 Synthetic 
Aperture Radar. IGARSS 2018, Valencia Spain, July 22-27, 2018. Posted 
08/09/2018
https://www.nass.usda.gov/Research_and_Science/Cropland/docs/Boryan_IGARSS2018%20_Flood.pdf

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File: Hurricane_Laura_Flood_Assessment_Report.pdf

Description: The Assessment Report provides a brief overview of the 
disaster event and the analysis that USDA/NASS conducted to estimate the 
extent of cropland and pasture/hay inundated by flooding from Hurricane Laura.
The report provides an overview of the raster data created 
with select zooms of affected cropland and pasture/hay. 

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There are several causes for anomalous water, which could include flooding, saturated fields from rainfall, ponding, or intentionally flooded rice and aquaculture fields.