Energy Balance Experiment, 2000

07/20/2000 - 08/24/2000

I have computed a preliminary budget for EBEX. This was created by compositing each term of the budget over the time period 10-20 August over all the stations which were available. All terms have all corrections, with the exception of the sonic tilt correction. The net radiation is just from the net radiometers -- I still have to compute the sum of the components.

The plot shows that we have closed the budget to within 30 W/m2 at all times of the day and that the sense of this imbalance is that more energy is leaving the surface than Rnet. This is the opposite of what previous investigations has shown. I believe that this is mostly due to the soil storage term -- without accounting for heat storage in the top 5cm of soil, the energy balance is off by up to 100 W/m2 in the other direction.

As for the other terms: clearly, most of the energy is in latent heat. Sensible heat was small due to the intense evapotranspiration of the cotton. Heat storage in the canopy (measured at only 2 sites) was almost 0 due partly to the (relatively) small amount of biomass, but mostly because the transpiring leaves reduced variations in the canopy temperature. Soil heat flux measured at 5cm also was relatively small.


Data Manager