GRIIDC | R4.x264.000:0059

Dataset Available

2004-2015 Southeastern Louisiana marsh Normalized Difference Vegetation Index (NDVI) changes between August and September from MODIS

Authors: Kearney, Michael Sean, Mo, Yu

Published On: Feb 21 2018 16:31 UTC

DOI: https://doi.org/10.7266/N7RB732G

UDI: R4.x264.000:0059

Files

Individual Files

No. of Downloads: 2

No. of Files: 2

File Size: 18.32 MB

File Format(s):
hdr, ENVI

Project Information

Funded By:
Gulf of Mexico Research Initiative

Funding Cycle:
RFP-IV

Research Group:
Coastal Waters Consortium II (CWC II)

Point of Contact

Michael Sean Kearney
University of Maryland / Department of Environmental Science and Technology
kearneym@umd.edu

Data Collection Period

2004-01-01

2015-12-31

Theme keywords

Macondo oil spill, MODIS

ISO 19115-2 Metadata

View Metadata

Abstract:

The data file consists of Normalized Difference Vegetation Index (NDVI) changes datasets of the southeastern Louisiana marshes generated from MODIS NDVI 16-day composites (Terre Product, MOD13Q1) from 2004 to 2015. The projection is the Lambert Azimuthal Equal Area. Spatial resolution is 250 meters by 250 meters. The dataset consists of 24 stacked files. They are percentage NDVI changes between mid-August and early September and between mid-August and late September in each year from 2004 to 2015. The percentage NDVI changes were calculated as: (after-NDIV – before-NDVI) * 100% / before-NDVI. The values of each pixel indicates different ranges of NDVI change in percentage: 6 is -100~-65%, 5 is for -65~-45%, 4 is for -45~-25%, 3 is for -25~-5%, 2 is for -5~+5%, and 1 is for > +5%. The 24 datasets are NDVI changes between the following dates (Year/before-day-after-day; in terms of Julian Day of Year): 2004/231-245,2004/231-273, 2005/229-243, 2005/229-271, 2006/228-242, 2006/228-270, 2007/226-240, 2007/226-268, 2008/232-246, 2008/232-274, 2009/230-244, 2009/230-272, 2010/229-243, 2010/229-271, 2011/228-242, 2011/228-270, 2012/234-248, 2012/234-276, 2013/232-246, 2013/232-274, 2014/231-245, 2014/231-273, 2015/230-244, 2015/230-272. Processing was done by Yu Mo, J.C. Alexis Riter, and Michael S. Kearney of the Department of Environmental Science and Technology, University of Maryland, College Park, MD 20742.

Suggested Citation:

Kearney, Michael Sean, Mo, Yu. 2018. 2004-2015 Southeastern Louisiana marsh Normalized Difference Vegetation Index (NDVI) changes between August and September from MODIS. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N7RB732G

Publications:

Mo, Y., Kearney, M. S., & Turner, R. E. (2020). The resilience of coastal marshes to hurricanes: The potential impact of excess nutrients. Environment International, 138, 105409. doi:10.1016/j.envint.2019.105409

Purpose:

To monitor Louisiana salt marshes after the Macondo oil spill using remote sensing.

Data Parameters and Units:

The Normalized Difference Vegetation Index (NDVI) is a unitless proxy in optical remote sensing for the amount of vegetation. NDVI ranges from minus one (-1.0) to plus one (+1.0). Usually, a NDVI close to zero or slightly positive means little or no vegetation and a NDVI close to +1 (0.8 - 0.9) indicates a very high density of green leaves.

Methods:

The MODIS MOD13Q1 data were downloaded from the USGS Earth Explorer website (http://earthexplorer.usgs.gov/). More information about the MOD13Q1 is available on its USGS official website: https://lpdaac.usgs.gov/dataset_discovery/modis/modis_products_table/mod13q1. Further processing of the data was performed using ENVI 4.8 (ITT Exelis, USA).