Intellectual Merit: Understanding advective-diffusive transport and production/destruction processes of dissolved constituents in natural fluid flows is an important challenge in Earth and environmental sciences with many diverse applications. Moreover, geophysical and environmental models routinely produce huge amounts of data. To make sense of these data novel diagnostic methods are required. Among these methods an increasingly popular and powerful approach uses real (or hypothetical) passive tracers to tag fluid masses and estimate transport pathways and timescales, such as tracer ages, residence time, and transit time. These timescales lead to insightful diagnoses that are increasingly applied in interdisciplinary environmental studies.
The International workshop/school on Tracer and Timescale Methods for Understanding Complex Geophysical and environmental Processes will review and explain what has been achieved so far in this field and suggest new developments. This is one-time event, held in August 2011 in Belgium. All junior scientists (PhD students and post-docs, especially) with interests in environmental tracer theory, modeling and observations are encouraged to participate. Tutorials will be delivered by members of an international scientific committee of experts in tracer techniques. In addition, student oral papers or posters will be presented with model studies, theoretical developments, field measurements ? for model validation or other purposes ? or numerical model studies, be they Eulerian or Lagrangian. The diagnostics may concern air, water, passive/inert tracers, biogeochemical variables, sediment particles, etc.
Broader Impacts: The field of tracer timescale methods in environmental flows will be advanced through scholarly discussions at the workshop and collaborations that ensue. The workshop will also contribute to the education of a new generation of young researchers who will be able to use in tracer timescale methods for a broad range of environmental problems.
. The Workshop/School lasted 3.5 days in August 2011 and was held at the Universite Catholique de Louvain in Louvain-la-Neuve, Belgium. The goal of the school was to teach junior researchers, like PhD students, about new methods in a field of environmental science called tracer timescale methods. There are several familiar examples of topics that fall in this category. Radioactive substances spreading from the Chernobyl and Fukushima nuclear accidents is one example. Understanding how agro-chemicals, like fertilizers and pesticides, spread into ground water is another. And the ways that the ocean can absorb and store the extra carbon dioxide gas from mankind's activities is a third example. These are all important questions in environmental and earth science. They have many common characteristics because they all involve the dispersal of a tracer (the radioactive substance, the fertilizer, or the extra carbon dioxide) by a fluid like the atmosphere, groundwater, or the ocean. In each case, we want to understand where the tracer will go and how fast. The Tracer Workshop/School explained how these processes are all related and how to quantify the spreading of the tracer in each case. Students learned how to use new tools to understand these processes among others examples. The Workshop/School involved lectures from 13 scientists from 12 different institutions. Five of the lecturers were from the US. There were 43 students in total with 12 of them from the US. These 12 US participants came from Johns Hopkins University, The University of Washington, The University of Colorado, The University of California at Irvine, The University of Hawaii, Virginia Institute of Marine Science, and Columbia University. The National Science Foundation award covered the travel expenses of these students. The travel expenses of the US lectureres were covered by other sources.