Temporal Change Evaluation
Canopy roughness and moisture content vary over the growing season. Radar is sensitive to these differences in contrasting backscatter during the growing season. This allows for the evaluation of change in backscatter over several dates and evaluation of temporal change in crop parameters.

RADARSAT beam mode - The size of the agricultural field being imaged should be taken into consideration when choosing a beam mode. Ideally, the beam mode resolution should be several times smaller than the size of the agricultural fields (i.e., Fine or Standard beam mode).

RADARSAT incidence angle- The main parameter differentiating crop type associated with temporal change is geometric structure from individual plants; shallow incidence angles maximize the contrast in backscatter resulting from differences in plant geometric structure. The beam mode chosen for all data acquisitions should be identical in order that any detected change be a result of a change in crop parameters and not a result of a change in sensor parameters.

Look direction - A look direction perpendicular to row direction maximizes backscatter from the crop canopy (as opposed to from the soil surface). The look direction chosen for all data acquisitions should be identical in order that any detected change be a result of a change in crop parameters and not a result of a change in sensor parameters. An ascending (18:00 H local time) pass may be preferred to minimize the presence of dew which may decrease interpretation and classification accuracy. Conversely, the descending pass (06:00 H local time) may reduce the effects of rain events in areas of convection related rainfall.

When to acquire RADARSAT data - Acquire data during the time periods that require crop change to be evaluated.