Data Set Name: NDVI 1999 Contact Person Steven F. Oberbauer Department of Biological Sciences Florida International University Miami, FL 33199 ph: 305-348-2580 email: oberbaue@fiu.edu Source of support: OPP-9615845. This work is part of the U.S. effort of the international tundra experiment (ITEX) Study site Toolik Lake Field station, east facing slope above entrance stream to lake Purpose: document differences in on study site in control and treatment plots Treatments controls, snow removal (May 2), snow removal + soil heating (heating started May 4). Design 10 replicates of each treatment in randomized blocks located 3 m apart. Treatment plots are 1.5 x 1.5 m. Sampling frequency weekly Techniques We used a digital camera (Dycan ADC agricultural camera) to monitor changes in Normalized Difference Vegetation Index (NDVI) on our season-length manipulation treatments. The camera uses optical filters to select the desired wavelengths. Digital images were taken biweekly throughout the growing season in 1999. The camera was calibrated to a teflon reference plate. Images were analyzed using image analysis software (BRIV-32) which calculates NDVI and maps it in false color on to the image. We attempted to take images only under sunny conditions but that was not always possible. Level of precision 0.05-0.1 Data Format Microsoft Excel 97. Computer Data prepared on Dell Optiplex running Window 95 Data fields YYYYMMDD (integer), Date (integer), Day of year (integer), Treatment (alphanumeric), Plot (integer), NDVIbase (real), NDVI (plot), Calplate (real). Browse Images All the images used for the construction of this data set are provided. Images are JPG files with oberbauer_ndvi_dd,mon,year-plot.jpg as the name. Conditions for use: Permission of contact required prior to release. NOTE: JPG Filename convention is: oberbauer_ndvi_DDMMYY-##.jpg where ## is picture number.