Temporal and spatial thermal radiation distribution analysis within and above crop canopies by 3D simulation

The thermal radiation distribution within and above the canopy is explored. CUPID model is chosen to simulate the canopy component temperatures. TRGM model, based on 3D realistic structure and radiosity solution, is used to simulate the component brightness temperature distribution within canopy and thermal radiation emission directionality distribution T-B (theta) above canopy. It is noted that the shape of vegetation component temperature profile mostly like an inverse "S" curve. Component temperature histogram is very good indicator to show daily variation. The difference between component brightness temperature and thermodynamic temperature mainly varies with LAI, relative height and leaf angle distribution. Through establishing relationship between T-B (theta) variation, LAI and environmental parameters on crop canopies, the temporal effects or angular effects of the thermal radiation distribution is discussed.