Dr. Robin Bell
Earth Institute Contact: Dr. Robin Bell
Additional External Researchers:
Jennifer Wong, GISS, EEC, CERC, The Virtual Estuary (a collaborative effort between the Earth Engineering Center, Environmental Molecular Sciences Institute (EMSI), COAST (The Clean Ocean And Shore Trust, a bistate goverment agency) and Rutgers)
Locations: United States of America
The Hudson River Estuary today is a complex system comprised of both ecological and physical components. The driving forces behind this systems include natural processes operating on time scales ranging from hours to thousands of years, and human impacts with time scales of days to decades. In recognition of the complex interplay between these disparate forces, and the pressing need for targeted decision-making, Columbia now focuses its Hudson River research within the framework of three primary management issues.
1. How can the Hudson River and New York Harbor be maintained as vital transportation arteries for local, state, national and international shipping?
2. How can the river's water be used for commercial and domestic purposes without adversely impacting the watershed and its many ecosystems?
3. How can the diverse estuary fisheries by maintained for both recreational and commercial use?
Specific Scientific Targets The overarching management issues discussed above translate into five specific research areas being pursued by Columbia scientists.
1. Understanding the Energy Budget of an Estuary
Discussion The Hudson River, its waters, it biota and its sediments are all fundamentally driven by the input of energy into the system. The system's natural energy budget includes the tides, the seaward movement of the water, warming from the sun, wind driven mixing and the erosion of sediments into the river. The energy budget is key to understanding and predicting the state of the river as it controls the movement of material such as sediments and contaminants and the delivery of nutrients to the various ecosystems. The natural energy budget has been modified and will continue to be modified by human activities. Flood control projects in the watershed, dredging of the navigational channel, power plants, the introduction of nutrients from wastewater facilities all impact the river's energy budget. Until we can understand the energy budget and results of the mixing within the river during an individual tidal cycle we cannot understand the impacts of change short term or long term, natural or human induced.
2. Deciphering the Functioning of an Urban Estuarine Ecosystem
Discussion In the last 20 years the Hudson River has gotten much cleaner but the system's nutrient load is still large due to the populations along the riverbanks. Some components of the system are well understood through ongoing studies by individual scientists but the overall functioning of the estuary ecosystem is not well constrained. Long term census information on the fish population has been collected but the linkages to the nutrients, plankton communities and bottom organisms is absent. Until the basic functioning of the ecosystem is understood, it is impossible to evaluate the impact of the human activities along the river including the presence of contaminants, entrainment of fish larvae and plankton by power plants, changing wastewater inputs, the introduction of exotic species and the impact of dams and development within the tributaries.
3. Documenting the Transport of Sediments through an Estuary
Discussion The evolution of the Hudson River from a deep narrow canyon 15,000 years ago to a shallow estuary today is the result of natural forcing functions including a global rise in sea level on the order of 300 feet, major changes in the size of Hudson watershed and changing climate as the earth moved from a major glacial period to the present warm inter-glacial period. The record of these changes is preserved within sediments of the river and along its banks. The sediments also have preserved a record of the ecosystems which were dominant through these major changes. The deciphering the history of the river from a fiord to an estuary is key to understanding the modern river processes and predicting the Hudson's response on new, possibly accelerated change. Today the river is experiencing ongoing changes to the climate and watershed, some natural and some exacerbated by human activities. Understanding the transport and preservation of the sediments in the modern river is important both as a basic science question and as a practical matter of identifying the location and fate of contaminated sediment.
4. Management of a Watershed in Support of both a Diverse Ecosystem and a Modern Mega-city
Discussion New York's water resources have been a critical component of the economic development of the region. Farsighted infrastructure investment and environment protection policies at the beginning of the twentieth century directly contributed to region's impressive record of economic development. As development pressure in the region continues and impacts the areas originally set aside to protect the region's water, we must look ahead to determine the water needs the region will face in the year 2100. We must address the same issue that was addressed by political and business leaders one hundred years ago: What must we do to assure a safe, plentiful and healthy water supply for the future? There is little question that the most cost-effective approach to protecting the water supply is to protect the natural ecology of the watershed the water is drawn from. The most graphic current example of the potential cost of environmental neglect is the multi-billion dollar price tag that has been placed on filtering all of New York City's water if the watershed's ecology is damaged.
5. Response of an Estuary to Global Change
Discussion In the geologically recent, highly engineered world of Manhattan global climate change and sea level rise seem like distant issues, but they are both real and ongoing. In fact, the Hudson has been responding to climate fluctuations throughout the millennia, and in unraveling this history lies the key to forecasting the future. Current global warming, whether caused or simply exacerbated by human activity, could significantly alter the annual cycle of Hudson River flow. Sea level, which has risen over 3 feet since New Amsterdam was established, will continue to impact the physical and biologic river systems altering the riverbanks and the input of carbon, nutrients and sediments. Understanding and anticipating the response of the Hudson River system to the full range of potential climate change scenarios is of paramount importance to the health and survival of the river, and indeed the entire New York City metropolitan area.
Cross Cutting Themes:
Project Web Site:
The School of International and Public Affairs, Columbia University
The School of Public Health, Columbia University