Advanced Very High Resolution Radiometer is used for TMAI crop monitoring and modeling.

Resolution one sq. kilometer (250 acre)

Coverage Up to 4 passes each day over any area of the world, with near-instant access to data. There are three satellites in operation

Data Cost Very low

TMAI

• AVHRR Receiving station
• 11- year crop/vegetation data-base of AVHRR data for the U.S., essential for crop modeling.
• 4 - year data-base for the rest of the World, essential for crop modeling

Advantages

• Good for monitoring vegetation change and condition on a real-time basis.
• Good for a regional perspective, to monitor trends, crop progress and condition, and for crop modeling.
• Areas such as the U.S. cornbelt and wheatbelt, States, or Crop Reporting Districts can be effectively monitored and modeled to give a complete picture of crop progress, stage of development, and condition
• Individual fields of 250 acres or smaller cannot be seen. This system is not used for precision agriculture.

This map shows final corn yield estimates for each 250 acres in Iowa, produced from AVHRR data. The red and yellow areas in the west central CRD show yields reduced by 60 bu/ac, due to early-season high winds and hail. This yield forecast was produced 6 weeks prior to harvest.

LANDSAT, SPOT SATELLITES

Resolution 10 - 30 sq meter Resolution

Coverage Satellite returns to same spot approx. every 16 days (LANDSAT) or must be contracted to fly over chosen areas (SPOT)

Data Cost High Cost approx. $400 - $4,400 per scene, each scene approx. 15,000sq miles or 80 x 75 miles square.

TMAI uses these satellites for initial identification of land-use/land-cover and long-term change detection.

Advantages

• Useful for land cover identification, mapping, and long-term change detection

Disadvantages

• Not useful for continuous crop monitoring.
• No historic database exists for either satellite, though individual scenes are available.
• Difficult to model over large areas due to high coast, lack of historic data sets, and limited real-time data quality and timely availability.

SATELLITES AND AIRCRAFT USED FOR PRECISION AG

Resolution 1-10 sq meter Resolution

Coverage Aircraft passes must be contracted for. Satellites not yet available for real-time monitoring high-resolution monitorning

Data Cost High cost per acre

Advantages

• Useful for monitoring crops at the field level.

Disadvantages

• High- resolution historic data not available for crop modeling over large areas.
• Real-time data costly

TMAI has conducted studies in conjuction with Resource 21 and is able to distinguish crop types and monitor crop conditions on the field level using this type of high--resolution data.