2015-2017 Gypsy Moth Defoliation Assessment (Southern New England)

-------------------------------------------------------------------------------------

THIS REPOSITORY IS NO LONGER ACTIVELY MAINTAINED.

Please see updated reanalysis products available here: https://zenodo.org/record/1493407#.XLikbpNKjOQ

-------------------------------------------------------------------------------------

This dataset accompanies the manuscript, "Extensive gypsy moth defoliation in Southern New England characterized using Landsat satellite observations", and includes Landsat time series-based estimates of gypsy moth defoliation for 2015, 2016, and 2017. The study area is defined by Landsat WRS-2 Path/Rows 12/31 and 13/31 and covers Southern New England (RI, CT, and southern MA). The following data products are available for each year:

• GeoTIFF of number of Landsat observations used to estimate changes in condition (*_nobs.tif)
• GeoTIFF of mean "condition" scores, where values represent the mean of the difference between observed and predicted Tasseled Cap Greenness normalized by the root mean squared error (RMSE) of a harmonic regression model fit to a 10-year time series of greenness observation for each pixel (*_meanresiduals.tif)
• GeoTIFF of masked condition scores, where non-forested areas in the mean condition score dataset have been excluded (nodata=-9999) based on a forest/non-forest mask generated from the National Land Cover Dataset (*_meanresiduals_forestmask.tif). The NLCD mask is also included (NLCD_forest_mask.tif)
• JPEG images showing final products where average difference scores were binned into four severity categories: slight change (deviations 1 to 2 times the model RMSE), moderate change (deviations 2 to 3 times the model RMSE), large change (deviations 3 to 4 times the model RMSE), and very large change (deviations greater than 4 times the model RMSE) 

All GeoTIFFs are georeferenced and provided in NAD/Conus Albers (EPSG: 5070).

Near-real-time monitoring results (i.e. condition score GeoTIFFs for each acquisition date during the May-September monitoring period) available by request.

For more on the methods used to generate these datasets, see Pasquarella, V.J., Bradley, B.A, & Woodcock, C.E. Near-real-time monitoring of insect defoliation using Landsat time series. Forests 8(8), 275; doi:10.3390/f8080275, available online: http://www.mdpi.com/1999-4907/8/8/275