STRESS Sponsors

STRESS 2 - A workshop co-sponsored by:

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


NOV  4-6, 2009

Workshop Objectives

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 other disciplines.. We will continue to identify:

1. Geomorphic and hydrologic processes which posess many scales of motion and for which physical justification and observation suggest exploration of heavy-tailed stochastic theories and fractional transport models.
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.

Key properties of surface systems

The 3-day workshop will consist of oral sessions, group discussion, and breakout groups. Oral sessions will be held on previous applications of stochastic models at the Earth surface and open questions in Earth surface science that may benefit from novel mathematical approaches. We solicit only talks that fit within these categories. Because of increased interest in the STRESS 2 workshop, we request only one abstract per research group. Organizers will develop the conference program with participants in September.

Abstracts are due October 1, 2009.

Workshop Participants & Organizers


Efi Foufoula-Georgiou
Director, National Center for Earth-Surface
Dynamics (NCED)
Department of Civil Engineering and
St. Anthony Falls Laboratory
University of Minnesota
Rina Schumer
Division of Hydrologic Sciences
Desert Research Institute
Reno, Nevada


Christophe Ancey 
Boris Baeumer 
Nandita Basu 
David Benson 
Nate Bradley
Gia Destouni
Efi Foufoula-Georgio
Vamsi Ganti 
Ciaran Harman 
Kimberly Hill
Doug Jerolmack
Mark Meerschaert 
Clement Narteau 
Aaron Packman
Rishi Parashar
Matt Reeves
Rina Schumer
Sally Thompson
Vaughan Voller 
Ilya Zaliapin 
Yong Zhang 

Workshop Presentations

Workshop Program 

STRESS2 Short Course: Heavy-tailed stochastic processes and fractional ADEs for modeling particle transport.


Christophe Ancey - Alternative(s) to fractional-diffusion equations in bedload-transport models

Boris Baeumer - Tutorial: Numerical methods for fractional PDEs... and more?

andita Basu - Biogeochemical Filtering of Solute Signals During Transport Through Hillslopes

David Benson - Emergent heavy tails of reaction rates in diffusion-limited regimes and the self-organized patterns of reactants.

Nate Bradley - Fractional Dispersion in a Sand-Bed River

Gia Destouni - The mass in the tail: flow and transport through hydrological catchments across spatio-temporal scales  (presentation) 

Efi Foufoula-Georgiou -  Non-Locality in Geomorphic Transport Laws and Implications for Landscape Evolution Models  (presentation)

Vamsi Ganti - Signature of non-locality in depositional systems: Implications for modeling and interpretation of stratigraphic records   (presentation) 

Ciaran Harman - Cascading water and solute transport through the vadose zone: advection, dispersion, and transformations in highly non-steady flow   (presentation)

Kimberly Hill - Probability of travel distances in gravel bedload transport: size dependence

Doug Jerolmack - Turbulent' sediment transport with memory: experimental constraints on the nature of fluctuations in sediment transporting systems   (presentation) 

Brandon McElroy - Temporal scaling of sediment flux and topographic change in a sandy channel   (presentation)

Mark Meerschaert - Fractional calculus models for the earth surface:   Success to date, challenges, and opportunities  (presentation)

Clement Narteau - Morphodynamics of superimposed bedforms in a lattice gas cellular automaton dune model  (presentation)

Aaron Packman - Linking pore structure, pore fluid flow, colloid deposition, and solute transport behavior over multiple scales   (presentation)

Rishi Parashar - Dynamics of motile microbes   (presentation)

Matt Reeves - A Subordinated Kinematic Wave Equation for Heterogeneous Hillslopes: Saturated Flow Solutions to Applied Impulses and Future Incorporation of the Vadose Zone   (presentation)

Rina Schumer - Using heavy-tailed stochastic models to interpret an incomplete geologic record   (presentation)

Sally Thompson - A Parsimonious Model for Transport of Fine Sediments in Rivers

Vaughan Voller - Two demonstrations of the theoretical and physical nature of fractional diffusion   (presentation)

Ilya Zaliapin - Tokunaga trees, dynamical trees, and BDE modeling of river transport

Yong Zhang - Tutorial: "Almost power law": Tempered power-law models  (presentation)

Yong Zhang - Tutorial: Particle tracking methods for fractional ADES   (presentation)


Workshop Location, Accommodations, and Travel

Daily meetings will be held at the  Tahoe Environmental Research Center (TERC) in Incline Village, Nevada.

The Hyatt Regency Lake Tahoe is located on the east shore of Lake Tahoe, a five-minute walk from the TERC.  Hotel reservations under each invited participant.s name will be paid in advance.  Meals will be provided at the conference center.

Ground transportation from the airport to the hotel can be provided for those arriving on Tuesday morning (contact us). Otherwise, you can take a shuttle: ($40), cab (~$100), or rent a car (~$30/day).

A map showing how to get from the hotel to the conference center (5 minute walk) is here

Hyatt HotelTravel Reimbursement

Meals and lodging will be provided for invited participants by NCED and Hydrologic Synthesis. Limited travel assistance can be provided upon request. Pre-approved travel reimbursement can be obtained by sending receipts and a Participant Expense Worksheet to:


National Center for Earth-surface Dynamics 
Attn: Theresa Compton 
2 - 3rd Ave SE RM 379 
Minneapolis, MN 55414