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Tools and Animations

Please read these cautions before using the tools.

Data

NDVI Download

Bi-weekly NDVI images for 1989 to the present for the co-terminous US and Arizona are available at our NDVI download page on ARIA.

More Information

Ecological Site Guides

From the AZ AgNIC Managing Rangelands Web site, this site contains information on the ability of land to produce vegetation based on characteristics of the land and climate.

NDVI Reference

For more information on what NDVI is and how you can use it, try this tutorial from Nasa's Earth Observatory website.

AZ AgNIC Geospatial Tools

Cautions:

* Between 1989 and 1995, the NOAA-11 satellite was the source for AVHRR data. From 1995 to 2000, the NOAA-14 satellite provided AVHRR sensor coverage. Since 2001 the NOAA-16/AVHRR and Terra/MODIS satellites are utilized to provide NDVI data. Data acquired in 1994 and in the end of 2000 were pulled from Rangeview due to sensor degradation and data inconsistencies. All data (1989-present) has been corrected for the effects of atmospheric water vapor. The continuity of the NDVI values derived from different satellites and sensors are being investigated to make the time series of AVHRR data as consistent as possible. Current cross-sensor NDVI comparisons should be evaluated with caution, especially after the year 2000.

** These tools are meant to complement rather than replace traditional monitoring methods. Note that the relatively coarse spatial resolution limits the ability to draw site-specific conclusions. Instead, these tools are useful in looking at differences across large areas and over time.