Skip to main content
Advanced Search

Filters: Tags: NDVI (X)

104 results (12ms)   

Filters
Date Range
Extensions
Types
Contacts
Categories
Tag Types
Tag Schemes
View Results as: JSON ATOM CSV
thumbnail
Locating meadow study sitesMeadow centers as recorded in the ‘Copy of sitecords_areaelev from Caruthers thesis.xls’ file delivered by Debinski in November 2012 were matched to polygons as recorded in files ‘teton97map_area.shp’ and ‘gallatin97map_area.shp’ both also delivered by Debinski in November 2012.In cases where the meadow center did not fall within a meadow polygon, if there was a meadow polygon of the same meadow TYPE nearby (judgment was used here), the meadow center was matched with the meadow polygon of same meadow TYPE. In total, 29 of 30 Gallatin meadow sites and 21 of 25 Teton meadow sites were positively located.Identifying meadow pixels for analysisThe native MODIS 250-meter grid was reprojected...
thumbnail
This dataset provides an estimate of 2015 cheatgrass percent cover in the northern Great Basin at 250 meter spatial resolution. The dataset was generated by integrating eMODIS NDVI satellite data with independent variables that influence cheatgrass germination and growth into a regression-tree model. Individual pixel values range from 0 to 100 with an overall mean value of 9.85 and a standard deviation of 12.78. A mask covers areas not classified as shrub/scrub or grass/herbaceous by the 2001 National Land Cover Database. The mask also covers areas higher than 2000 meters in elevation because cheatgrass is unlikely to exist at more than 2% cover above this threshold. Cheatgrass is an invasive grass that has invaded...
thumbnail
The capacity of ecosystems to provide services such as carbon storage, clean water, and forest products is determined not only by variations in ecosystem properties across landscapes, but also by ecosystem dynamics over time. ForWarn is a system developed by the U.S. Forest Service to monitor vegetation change using satellite imagery for the continental United States. It provides near real-time change maps that are updated every eight days, and summaries of these data also provide long-term change maps from 2000 to the present. Based on the detection of change in vegetation productivity, the ForWarn system monitors the effects of disturbances such as wildfires, insects, diseases, drought, and other effects of weather,...
thumbnail
This dataset provides early estimates of 2021 exotic annual grasses (EAG) fractional cover predicted on May 3rd. We develop and release EAG fractional cover map with an emphasis on cheatgrass (Bromus tectrorum) but it also includes number of other species, i.e., Bromus arvensis L., Bromus briziformis, Bromus catharticus Vahl, Bromus commutatus, Bromus diandrus, Bromus hordeaceus L., Bromus japonicus, Bromus madritensis L., Bromus racemosus, Bromus rubens L., Bromus secalinus L., Bromus texensis (Shear) Hitchc., and medusahead (Taeniatherum caput-medusae. The dataset was generated leveraging field observations from Bureau of Land Management (BLM) Assessment, Inventory, and Monitoring data (AIM) plots; Harmonized...
This imagery was collected and produced for a set of large fires sampled from within the Great Northern Landscape Conservation Cooperative study area. This imagery and associated metrics was produced using Landsat 5 and 7. This set of imagery and remote sensing metrics have the following file structure: 1. Each sub-folder in the Fires LC Map folder represents an individual fire. 2. Within the folder there are 8 raster tiffs. 1. XXX_post_refl.tif The at-sensor-reflectance of the postfire landsat scene, named with the PolyID unique identifier for the fire, stored in 8-bit i. Band 1 of the Tiff is Band 3 (Red) of Landsat ii. Band 2 of the Tiff is Band 4 (NIR) of Landsat iii. Band 3 of...
This imagery was collected and produced for a set of large fires sampled from within the Great Northern Landscape Conservation Cooperative study area. This imagery and associated metrics was produced using Landsat 5 and 7. This set of imagery and remote sensing metrics have the following file structure: 1. Each sub-folder in the Fires LC Map folder represents an individual fire. 2. Within the folder there are 8 raster tiffs. 1. XXX_post_refl.tif The at-sensor-reflectance of the postfire landsat scene, named with the PolyID unique identifier for the fire, stored in 8-bit i. Band 1 of the Tiff is Band 3 (Red) of Landsat ii. Band 2 of the Tiff is Band 4 (NIR) of Landsat iii. Band 3 of...
thumbnail
These datasets provide early estimates of 2022 fractional cover for exotic annual grass (EAG) species and one native perennial grass species on a bi-weekly basis from May to early July. The EAG estimates are developed within one week of the latest satellite observation used for that version. Each bi-weekly release contains four fractional cover maps along with their corresponding confidence maps for: 1) a group of 16 species of EAGs, 2) cheatgrass (Bromus tectorum); 3) medusahead (Taeniatherum caput-medusae); and 4) Sandberg bluegrass (Poa secunda). These datasets were generated leveraging field observations from Bureau of Land Management (BLM) Assessment, Inventory, and Monitoring (AIM) data plots; Harmonized Landsat...
thumbnail
This study uses growth in vegetation during the monsoon season measured from LANDSAT imagery as a proxy for measured rainfall. NDVI values from 26 years of pre- and post-monsoon season Landsat imagery were derived across Yuma Proving Ground (YPG) in southwestern Arizona, USA. The LANDSAT imagery (1986-2011) was downloaded from USGS’s GlobeVis website (http://glovis.usgs.gov/). Change in NDVI was calculated within a set of 2,843 Riparian Area Polygons (RAPs) up to 1 km in length defined in ESRI ArcMap 10.2.
thumbnail
These datasets provide early estimates of 2024 fractional cover for exotic annual grass (EAG) species and one native perennial grass species on a weekly basis from April to late June. Typically, the EAG estimates are publicly released within 7-13 days of the latest satellite observation used for that version. Each weekly release contains five fractional cover maps along with their corresponding confidence maps for: 1) a group of 16 species of EAGs, 2) cheatgrass (Bromus tectorum); 3) Field Brome (Bromus arvensis); 4) medusahead (Taeniatherum caput-medusae); and 5) Sandberg bluegrass (Poa secunda). These datasets were generated leveraging field observations from Bureau of Land Management (BLM) Assessment, Inventory,...
thumbnail
These datasets provide early estimates of 2024 fractional cover for exotic annual grass (EAG) species and one native perennial grass species on a weekly basis from April to late June. Typically, the EAG estimates are publicly released within 7-13 days of the latest satellite observation used for that version. Each weekly release contains five fractional cover maps along with their corresponding confidence maps for: 1) a group of 16 species of EAGs, 2) cheatgrass (Bromus tectorum); 3) Field Brome (Bromus arvensis); 4) medusahead (Taeniatherum caput-medusae); and 5) Sandberg bluegrass (Poa secunda). These datasets were generated leveraging field observations from Bureau of Land Management (BLM) Assessment, Inventory,...
Quantitative assessment of forest burn severity and determination of its spatial variation are important for post-fire forest restoration and forest fire management. In this paper, we assessed forest burn severity using pre- and post-fire Landsat TM/ETM+ data and field-surveyed data and explored the spatial variation in burn severity and its influencing factors. Our results showed a relatively strong linear relationship between normalized burn ratio (NBR) and composite burn index (CBI) (R2 = 0.63), suggesting that NBR was the best spectral index and could be used to assess forest burn severity in Heilongjiang Province. The forest burn severity showed obvious spatial variation. The majority of heavily burned areas...
thumbnail
These data are aerial image-derived, classification maps of tamarisk (Tamarisk spp.) in the riparian zone of the Colorado River from Glen Canyon Dam to Separation Canyon, a total river distance of 412 km. The classification maps are published in GIS vector format. Two maps are published: 1) a classification of tamarisk from a 0.2 m resolution multispectral image dataset acquired in May 2009 (Tamarisk Classification 2009), and 2) a classification of tamarisk impacted by the tamarisk beetle (Diorhabda carinulata) from a 0.2 m resolution multispectral image dataset acquired in May 2013 (Beetle Impact Classification 2013). Tamarisk presence in 2009 was classified using the Mahalanobis Distance method with a total of...
thumbnail
This dataset provides an estimate of 2015 cheatgrass percent cover in the northern Great Basin at 250 meter spatial resolution. The dataset was generated by integrating eMODIS NDVI satellite data with independent variables that influence cheatgrass germination and growth into a regression-tree model. Individual pixel values range from 0 to 100 with an overall mean value of 9.85 and a standard deviation of 12.78. A mask covers areas not classified as shrub/scrub or grass/herbaceous by the 2001 National Land Cover Database. The mask also covers areas higher than 2000 meters in elevation because cheatgrass is unlikely to exist at more than 2% cover above this threshold. Cheatgrass is an invasive grass that has invaded...
thumbnail
These data were compiled to understand the effects of riparian vegetation health on local abundance and species diversity of land birds. The primary objective of our study was to to determine the effects of riparian restoration on birds in the Colorado River delta. These tabular data represent vegetation indices and evapotranspiration (ET) data at varying spatial scales that correspond to avian use circles of 100 to 2000 meters. Three vegetation reflectance indices (VIs): NDVI, EVI, and EVI2 were obtained from Landsat imagery with a biweekly temporal frequency, and covering the entire period of bird surveys (2002-2020). The Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) and two-band...
This imagery was collected and produced for a set of large fires sampled from within the Great Northern Landscape Conservation Cooperative study area. This imagery and associated metrics was produced using Landsat 5 and 7. This set of imagery and remote sensing metrics have the following file structure: 1. Each sub-folder in the Fires LC Map folder represents an individual fire. 2. Within the folder there are 8 raster tiffs. 1. XXX_post_refl.tif The at-sensor-reflectance of the postfire landsat scene, named with the PolyID unique identifier for the fire, stored in 8-bit i. Band 1 of the Tiff is Band 3 (Red) of Landsat ii. Band 2 of the Tiff is Band 4 (NIR) of Landsat iii. Band 3 of...
This imagery was collected and produced for a set of large fires sampled from within the Great Northern Landscape Conservation Cooperative study area. This imagery and associated metrics was produced using Landsat 5 and 7. This set of imagery and remote sensing metrics have the following file structure: 1. Each sub-folder in the Fires LC Map folder represents an individual fire. 2. Within the folder there are 8 raster tiffs. 1. XXX_post_refl.tif The at-sensor-reflectance of the postfire landsat scene, named with the PolyID unique identifier for the fire, stored in 8-bit i. Band 1 of the Tiff is Band 3 (Red) of Landsat ii. Band 2 of the Tiff is Band 4 (NIR) of Landsat iii. Band 3 of...
thumbnail
These datasets provide early estimates of 2023 fractional cover for exotic annual grass (EAG) species and one native perennial grass species on a weekly basis from May to early July. The EAG estimates are developed typically within 7-13 days of the latest satellite observation used for that version. Each weekly release contains four fractional cover maps along with their corresponding confidence maps for: 1) a group of 16 species of EAGs, 2) cheatgrass (Bromus tectorum); 3) medusahead (Taeniatherum caput-medusae); and 4) Sandberg bluegrass (Poa secunda). These datasets were generated leveraging field observations from Bureau of Land Management (BLM) Assessment, Inventory, and Monitoring (AIM) data plots; Harmonized...
thumbnail
This tabular, machine-readable CSV file contains annual phenometrics at locations in ponderosa pine ecosystems across Arizona and New Mexico that experienced stand-clearing, high-severity fire. The locations represent areas of vegetative recovery towards pre-fire (coniferous/pine) vegetation communities or towards novel grassland, shrubland, or deciduous replacements. Each sampled area is associated with the point location (latitude/longitude) as well as multiple calendar year phenometrics derived from the time-series of normalized difference vegetation index (NDVI) values in the phenology software package Timesat v3.2.
thumbnail
The study's goal was to downscale 2013 250-m expedited Moderate Resolution Imaging Spectroradiometer (eMODIS) Normalized Difference Vegetation Index (NDVI) to 30 m (Gu, Y. and Wylie, B.K., 2015, Developing a 30-m grassland productivity estimation map for central Nebraska using 250-m MODIS and 30-m Landsat-8 observations, Remote Sensing of Environment, v. 171, p. 291-298)using 2013 Landsat 8 data. The eMODIS NDVI was downscaled for four periods: mid spring, early summer, late summer and mid fall. The objective was to capture phenologies during periods that correspond to 1) annual grass growth, 2) annual grass senescence, 3) the optimal NDVI profile separation between sagebrush and other shrubs in the region, and...
thumbnail
These data were compiled for evaluating river-reach level vegetation greenness data in the riparian corridor of the Colorado River delta as specified under Minute 319 of the 1944 Water Treaty. The seven reach areas from the Northerly International Boundary (NIB) to the end of the delta at the Sea of Cortez were defined for research activities. Also, these seven reaches are being monitored under Minute 323 of the 1944 Water Treaty. Additionally, these data were compiled for evaluating restoration-level vegetation greenness data in Reach 2 and Reach 4, as specified under Minute 323 of the 1944 Water Treaty. Objectives of our study were to measure satellite vegetation index data, specifically using the Enhanced Vegetation...


map background search result map search result map Hydrological Analysis of Greater Yellowstone Ecosystem Montane Meadow Condition using MODIS data Near-real-time cheatgrass percent cover in the northern Great Basin, USA--2015 ForWarn Mean Summer National Difference Vegetation Index 2009-2013 Mean of the Top Ten Percent of NDVI Values in the Yuma Proving Ground during Monsoon Season, 1986-2011 Estimating downscaled eMODIS NDVI using Landsat 8 in the central Great Basin shrub steppe Remote sensing derived maps of tamarisk (2009) and beetle impacts (2013) along 412 km of the Colorado River in the Grand Canyon, Arizona Near-real-time cheatgrass percent cover in the northern Great Basin, USA--2015 Phenology pattern data indicating recovery trajectories of ponderosa pine forests after high-severity fires Colorado River Delta Project: A compilation of vegetation indices, phenology assessment metrics, and estimates of evapotranspiration for circular bird plots in the Colorado River delta between 2000-2020 (ver. 1.0) Early Estimates of Exotic Annual Grass (EAG) in the Sagebrush Biome, USA, May 2021, v1 Average growing season normalized difference vegetation index (NDVI) data for the riparian corridor of the Colorado River Delta in Mexico from 2000-2020 5. Early Estimates of Exotic Annual Grass (EAG) in the Sagebrush Biome, USA, 2022 (ver 6.0, July 1st, 2022) Early Estimates of Exotic Annual Grass (EAG) in the Sagebrush Biome, USA, 2023 (ver. 1.0, May 2023) Early Estimates of Exotic Annual Grass (EAG) in the Sagebrush Biome, USA, 2024 Early Estimates of Exotic Annual Grass (EAG) in the Sagebrush Biome, USA, 2024 (ver. 2.0, April 2024) Hydrological Analysis of Greater Yellowstone Ecosystem Montane Meadow Condition using MODIS data Colorado River Delta Project: A compilation of vegetation indices, phenology assessment metrics, and estimates of evapotranspiration for circular bird plots in the Colorado River delta between 2000-2020 (ver. 1.0) Average growing season normalized difference vegetation index (NDVI) data for the riparian corridor of the Colorado River Delta in Mexico from 2000-2020 Mean of the Top Ten Percent of NDVI Values in the Yuma Proving Ground during Monsoon Season, 1986-2011 Remote sensing derived maps of tamarisk (2009) and beetle impacts (2013) along 412 km of the Colorado River in the Grand Canyon, Arizona Phenology pattern data indicating recovery trajectories of ponderosa pine forests after high-severity fires Estimating downscaled eMODIS NDVI using Landsat 8 in the central Great Basin shrub steppe Near-real-time cheatgrass percent cover in the northern Great Basin, USA--2015 Near-real-time cheatgrass percent cover in the northern Great Basin, USA--2015 ForWarn Mean Summer National Difference Vegetation Index 2009-2013 Early Estimates of Exotic Annual Grass (EAG) in the Sagebrush Biome, USA, 2024 Early Estimates of Exotic Annual Grass (EAG) in the Sagebrush Biome, USA, May 2021, v1 5. Early Estimates of Exotic Annual Grass (EAG) in the Sagebrush Biome, USA, 2022 (ver 6.0, July 1st, 2022) Early Estimates of Exotic Annual Grass (EAG) in the Sagebrush Biome, USA, 2023 (ver. 1.0, May 2023) Early Estimates of Exotic Annual Grass (EAG) in the Sagebrush Biome, USA, 2024 (ver. 2.0, April 2024)