The CUNY Summer Synthesis Institute on Human-Hydrologic Interactions took place in New York City from June 15 through July 27. Twelve graduate scholars from universities across the United States took part in the six-week program researching the relationships between hydrologic and human systems in Northeastern United States during the nineteenth century. This is the second in a series of four annual Institutes, funded by NSF, tracing human-water interactions over a 500-year period (1600-2100). Students came from a wide range of disciplines: hydrology, geomorphology, geography, geochemistry, landscape ecology, climatology, economics, history, and engineering. Their stated research goal was to "quantify the widespread alteration of hydrologic systems over local-to-regional domains focusing on the Northeast corridor of the United States." They developed the following question to guide their research, "to what degree was water availability (defined as both quantity and quality) constrained by natural factors and human activities?" The research approaches employed during the six weeks were: modeling of the hydrologic cycle; mining contemporary sediment cores, written records, and industrial data to understand historical pollution; synthesizing spatial and temporal information about landscape change and resulting sedimentation; and assessing the impact of the burgeoning canal and railroad transportation networks on the hydrologic cycle. During the institute, speakers and faculty participated weekly, assisting scholars in their research. Visiting mentors to the scholars included: Jennifer Arrigo (East Carolina U.), Dan Bain (U. Pittsburgh), Upmanu Lall (Columbia U.), Martin Melosi (U. Houston), Adam Schlosser (M.I.T.), Robert Thorson (U. Connecticut), Richard Vogel (Tufts U.), and Wil Wollheim (U. New Hampshire). Among the research results, scholars found that there was an increasing trend in runoff during the 1800s and that the wetter period that followed intensive deforestation was, in part, the cause of this trend. Human engineered storage increased between 1800 and 1900, from +0.5mm to approximately +.15mm. Water stress, in terms of compromised water quality, was increased significantly due to manufacturing and population growth in urban centers. The concentration of pollutants in sediments in the Northeast increased dramatically during the latter half of the nineteenth century, due to increased manufacturing. The Summer Synthesis Institute served as a springboard for scholars' future research and many of them are incorporating this research into their graduate work. The scholars are continuing their research over the fall and will be presenting their research during the Fall AGU meeting.

Dr. Murugesu Sivapalan and colleagues from the University of Illinois at Urbana-Champaign are leading an effort to advance the predictability of human-induced change propagation (climatic, land-use and land-cover) through the hydrologic system, both in time and over space, using "synthesis". An intensive summer institute and concluding capstone symposium were recently held by this group in Vancouver, B.C. at the University of British Columbia.

A diverse selection of 11 students and 12 rotating mentors spent 6 weeks carving new paths using "hydrologic synthesis". This team used a patterns-based approach to demonstrate the feasibility of developing a novel, unified and robust predictive framework that is focused on the cascading of hydrologic variability across a range of scales (local -- hillslope -- watershed -- river basin), and their impact on nutrient transport and export.

The summer institute projects shared the common perspective of the landscape as comprising a set of dynamic, cascading, hierarchical, non-linear filters, which propagate and modify the variability inherent to the climatic and land-use inputs, and highlight the relative roles of climatic, transport (hydrologic) and reaction (biogeochemical) timescales, the role of memory or legacy effects, and the buffering role of ecosystems (e.g, vegetation, micro-organisms). Two specific paths of exploration included 1) analysis of inter-annual variability of the water balance and vegetation response, expressed as the ratio, H=E/W, of annual evapotranspiration (E) to plant available water (W), termed the Horton Index and 2) examination of inter-annual variability in nutrient delivery ratio (NDR) as moderated by interactions between hydrologic and biogeochemical processes across the climate-hillslope-stream network continuum.

CUAHSI co-hosted a concluding event, where 12 additional colleagues, primarily early career individuals, gathered to discuss the summer's work and share their own progress. Drs. Francina Dominguez (Arizona) and Darrel Jenerette (UC-Riverside), 2007 CUAHSI Early Career Fellows, were among the attendees. Summer institute students and mentors are now preparing to formally present their results at Fall AGU.

Students: Antoine Aubeneau (Northwestern), Kaiyu Guan (Princeton), Ciaran Harman (Illinois), Sally Thompson (Duke), Hal Voepel (Nevada-Reno/DRI), Mary Yaeger (Illinois), Sheng Ye (Illinois), Stefano Zanardo (Purdue/Padua), Patrick Little (UBC - Session 3), Bryan Moravec (Arizona - Session 4), Andy Neal (Arizona - Session 4), Bart Rossman (Illinois - Session 1).

Mentors: Nandita Basu (Iowa), Paul Brooks (Arizona), Simon Donner (UBC), Matej Durcik (Arizona), Luigi Fraccarollo (Trento - Italy), Marwan Hassan (UBC), Gavan McGrath (UWA), Aaron Packman (Northwestern), Suresh Rao (Purdue), Ben Ruddell (Arizona State), Murugesu Sivapalan (Illinois), Peter Troch (Arizona).

Project PIs: Murugesu Sivapalan, Praveen Kumar, Don Wuebbles, Bruce Rhoads

Approximately 30 people participated in this workshop on emerging new instruments that could revolutionize research and monitoring in aquatic ecosystems. Participants included faculty and students from academic institutions in the US, Canada, and the UK as well as research professionals in government agencies and technical experts from industry. The workshop took a systems approach and began with a consideration of the principles of optical measurements, including spectrophotometric and fluorescent methods. Brian Pellerin, Bryan Downing, John Franco Saraceno, and Brian Bergamaschi from the USGS California Water Science Center provided a thorough overview of current technology for in-situ optical measurements and lead a discussion on practical considerations common to most in-situ optical measurements and various strategies for instrument deployment. Several workshop participants then drew on their personal experiences to discuss the considerable challenges that must be faced to deploy these instrument systems in rivers and lakes. Several industry representatives attended the workshop, including Andrew Barnard (WET Labs), Barrett Gaylord (Sontek/YSI), Cyril Dempsey (Satlantic) and David Alexander (s::can) which added a unique perspective to the discussions. The workshop focused on a group of in-situ optical tools that have recently become available including the ISUS in-situ ultraviolet spectrophotometer (Satlantic, Inc., Halifax, Nova Scotia, Canada), colored dissolved organic matter (CDOM) and chlorophyll fluorometers (e.g., WETLabs, Philomath, Oregon, USA), the AC-9 visible range spectrophotometer (WETLabs, Philomath, Oregon, USA), the model 6920 V2 multi-parameter sonde (YSI, Inc., Yellow Springs, Ohio, USA), and various pumps, regulators, dataloggers, and controllers that are commonly used to integrate and control these instruments. The participants also had the opportunity to beta-test and comment on a new in-situ (wet chemistry) auto-analyzer currently in production by WET Labs (the Cycle-P). The participants considered diverse aspects of in-situ optical instrument deployments including the rationales for instrument choices, the design and engineering of instrument systems, the challenges of different installation environments, the acquisition of data including data telemetry, and the management and analysis of data. Two active field deployments in Lake Champlain and a small urbanized stream provided hands-on experience with the instruments in a field trip setting. Jeff Horsburg from Utah State University joined the workshop remotely to explain how tools developed by CUAHSI's Hydrologic Information System could be employed to organize and publish data for others to use. The experience level of participants in the workshop ranged from novice to expert and included users and developers and so the discussions ranged from how these instruments work to how they could work better to serve the user community. Among several important recommendations the user group strongly advised instrument developers to consider ways to standardize key functions on their instruments (e.g. ports for power, input controller data, and output data) to facilitate interoperability of complex instrument systems. There was also a strong desire to create a user listserve to allow the community to more effectively communicate with each other about problems, tips, solutions, and recommendations. More information about this workshop including relevant literature and technical specifications of representative instruments can be found on the workshop website: www.cuahsi.org/hmf/sensor/index.html. Additional information from the workshop, including data produced and instructions to access the listserve will be posted at this site in the future. This workshop was supported by CUAHSI, the USGS California Water Science Center, and the Vermont Water Resources and Lake Studies Center.