Stochastic Transport and Emergent Scaling in Earth-Surface Processes

A workshop co-sponsored by:

National Center for Earth-surface Dynamics (NCED), University of Illinois, Hydrologic Synthesis Activities, and DRI

TAHOE CENTER FOR ENVIRONMENTAL RESEARCH
INCLINE VILLAGE, NV
NOV  4-6, 2009

Power-laws and scaling are frequently observed in Earth surface morphology suggesting that heavy-tailed stochastic models and fractional PDEs may be powerful tools for describing processes and transport laws that take place on the Earth’s surface from the hillslope to the whole river network. The STRESS 1 workshop, held in November 2007, catalyzed exploration of ideas, in research and applications, in the area of stochastic transport and emergent scaling in earth-surface processes. Using novel statistical mechanical tools we studied emergent behavior of physical processes characterized by extreme deviation from average behavior on a small scale. Approximately 20 manuscripts, including 15 in a special issue of Journal of Geophysical Research-Earth Surface, explore new models that can reproduce relevant features of sediment transport, retention, and deposition; deformation of bedforms; hillslope evolution and transport processes; landslide rupture and debris mobilization; and transport on river networks.

At the STRESS 2 workshop, we will again convene experts in Earth-surface processes and mathematicians and scientists who have successfully applied heavy-tailed stochastic theory and fractional differential equations in both Earth-surface science and other disciplines. We will continue to identify:

1. Geomorphic and hydrologic transport laws to which existing heavy-tailed stochastic theories and fractional calculus tools can be immediately applied
2. Outstanding theory required for the development of novel scale-invariant models for Earth surface processes

This year we also will investigate emergent biogeochemical patterns in watersheds.  Specifically, we will study

3. Combined effects of Earth surface morphology, residence time, and biogeochemical reactions on watershed output.