Self-organized criticality in atmospheric cascades

We argue that atmospheric cascades can be regarded as example of the self-organized criticality and studied by using Levy flights and nonextensive approach. It allows us to understand the scale-invariant energy fluctuations inside cascades in a natural way.Comment: gz-compressed .tar file containing LaTeX file and 5 PS files with figures, 4 pages altogether (Nucl. Phys. B style, espcrc2.sty file attached) Presented at XI International Symposium On Very High Energy Cosmic Ray Interaction, Campinas, Brazil, July 17-21, 2000. To be published in Nucl. Phys. B (Proc. Suppl.). Some typos correcte