Kardar-Parisi-Zhang Scaling of the Height of the Convective Boundary Layer and Fractal Structure of Cumulus Cloud Fields
نویسنده
چکیده
We present the cumulative frequency-area distribution of tropical cumulus clouds as observed from satellite and space shuttle images from scales of 0.1 to 1000 km. The distribution is a power-law function of area with exponent 20.8. We show that this result and the fractal dimension of cloud perimeters implies that the top of the convective boundary layer (CBL) is a self-affine interface with roughness exponent or Hausdorff measure H ø 0.4, the same value as that of the Kardar-Parisi-Zhang equation in 2 1 1 dimensions. In addition, we identify dynamic scaling in a time series of the local altitude of the top of the CBL as measured with FMyCW radar backscatter intensity. A possible growth model is discussed. [S0031-9007(97)02812-3]
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