Conditional sampling, bursting, and the intermittent structure of sensible heat flux

Sensible heat flux measurements were carried out to examine the characteristics related to frequency and duration of extreme flux events above a desert surface. First, the flux bursts were identified by a modified hyperbolic hole "quadrant analysis'. Second, the frequency distribution of the extreme flux burst length was examined. It was found that the frequency distribution of the burst length is well approximated by two- parameter power laws which account for two distinct types of bursting phenomena; one is organized, coherent, and has a relatively long duration, while the other is short lived, less organized, and has a relatively short duration. A strong correlation between bursting frequency and flux integral time scales was observed under a variety of atmospheric stability and surface wetness conditions. It was found that the variation in the interval between bursts for the dynamic and dynamic convective sublayers is strongly related to the variation in stability. -from Authors

Duke Scholars

Author Gabriel G. Katul Civil and Environmental Engineering