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NDVI from AVHRR
The sensor responsible for the longest running series of NDVI products used for large-area phenology studies is carried aboard National Oceanic and Atmospheric Administration (NOAA) polar-orbiting weather satellites (see Table 1). This sensor, known as the Advanced Very High Resolution Radiometer (AVHRR), has a daily repeat cycle and, despite its name, a 1-km resolution (an AVHRR image pixel represents 1 square km of land surface). AVHRR data are used to generate NDVI-based images of the planet’s land surface on a regular basis, thereby creating image series that portray seasonal and annual changes to vegetation worldwide. AVHRR NDVI data are available in a consistently processed database from 1982-present at an 8-km re-sampling grid covering the entire planet, and from 1989-present at a 1-km resolution for the conterminous United States.
Table 1. Low or no-cost satellite sensors and data streams utilized for land surface phenology studies1
| Sensor |
Satellite |
Overpass/
Orbit Frequency |
Data Source
(terrestrial data) |
Data Record
(years) |
Spatial
Resolution(s) |
Processed
Time Step |
Latency |
| AVHRR |
NOAA series |
Daily |
USGS/EROS2 |
1989-present |
1 km |
1-week, 2-week |
~24 hours |
| AVHRR |
NOAA series |
Daily |
Global Land Cover Facility3 |
1982-2006 |
8 km |
Twice monthly |
N/A |
| MSS |
Landsat 1-5 |
18 days |
USGS/EROS2 |
1972-1992 |
79 m |
Distributed by scene |
N/A |
| TM |
Landsat 4-5 |
16 days |
USGS/EROS2 |
1982-2011 |
30 m |
Distributed by scene |
N/A |
| ETM+ |
Landsat 7 |
16 days |
USGS/EROS2 |
1999-present |
30 m |
Distributed by scene |
~1-3 days |
| Vegetation |
SPOT |
1-2 days |
VITO4 |
1999-present |
1.15 km |
10-day |
~3 months |
| MODIS |
Terra |
1-2 days |
LPDAAC5 |
2000-present |
250 m, 500 m, 1 km |
8-day, 16-day |
~7-30 days |
| MODIS |
Aqua |
1-2 days |
LPDAAC5 |
2002-present |
250 m, 500 m, 1 km |
8-day, 16-day |
~7-30 days |
| eMODIS |
Terra/ Aqua |
1-2 days |
USGS/EROS6 |
2000-present |
250 m, 500 m, 1 km |
7-day |
~15 hours, 7 days6 |
1 Data sets are accessible for low- or no-cost for use in phenology research and applications (as of 1/4/2011).
2 USGS Global Visualization Viewer: (http://glovis.usgs.gov/)
3 GIMMS data set: (http://glcf.umiacs.umd.edu/data/)
4 Flemish Institute for Technology Research (VITO) for SPOT Vegetation S10 products: (http://www.spot-vegetation.com and http://free.vgt.vito.be)
5 Land Processes Distributed Active Archive Center: (https://lpdaac.usgs.gov/lpdaac/get_data)
6 eMODIS: (http://dds.cr.usgs.gov/emodis/), Latency is approximately 15 hours for expedited data (released daily) and around 7 days for historical data.
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U.S. Department of the Interior |
U.S. Geological Survey