Professor Howarth is the David R. Atkinson Professor of Ecology & Evolutionary Biology in the Department of Ecology and Evolutionary Biology at Cornell University. He is a biogeochemist and ecosystem scientist, an active research scientist who also enjoys teaching and is deeply involved in the environmental management and policy communities in the State, nationally, and internationally. His training was in oceanography, and much of his research still focuses on coastal marine ecosystems. However, he also works on freshwater systems (both rivers and lakes) and on large river basins.

Professor Howarth's research laboratory works broadly on human alteration of element cycles (particularly nutrients) in coastal marine ecosystems and in the watersheds that feed them. He also works on the environmental consequences of energy systems, particularly from oil and gas development and from biofuels, emphasizing water quality and greenhouse gas emissions. Specific current topics of study include:

  1. The biogeochemical feedbacks which may either aggravate or partially ameliorate eutrophication that occurs in seagrass-dominated systems as nutrient loads increase;
  2. The influences of climate change, land use, and management practices on the export of nutrients and sediment from large river basins;
  3. The importance of dry deposition of nitrogen gases from the atmosphere (particularly in the near proximity of vehicle emissions) as a source of nutrient pollution to coastal waters;
  4. The environmental consequences of biofuels;
  5. The greenhouse gas footprint of natural gas extracted from shale formations such as the Marcellus shale.

A more complete and current listing of Prof. Howarth's work and scholarly output can be found on his EEB Department web page and the Howarth & Marino Lab web site, or through the links below.

Google Scholar Page

ResearchGate Profile Page


Recent Submissions

  • Anthropogenic phosphorus inputs to a river basin and their impacts on riverine phosphorus fluxes along its upstream-downstream continuum 

    Zhang, W.S.; Swaney, D. P.; Hong, B.; Howarth, R. W. (Wiley, 2017-12-23)
    The increasing trend in riverine phosphorus (P) loads resulting from anthropogenic inputs has gained wide attention because of the well-known role of P in eutrophication. So far, however, there is still limited scientific ...
  • Human alteration of the global nitrogen cycle: Causes and consequences 

    Vitousek, P.M.; Aber, J.; Bayley, S. E.; Howarth, R. W.; Likens, G. E.; Matson, P. A.; Schindler, D. W.; Schlesinger, W. H.; Tilman, G. D. (Wiley, 1997-08-01)
    Nitrogen is a key element controlling the species composition, diversity, dynamics, and functioning of many terrestrial, freshwater, and marine ecosystems. Many of the original plant species living in these ecosystems are ...
  • Human health effects of a changing global nitrogen cycle 

    Townsend, A. R.; Howarth, R. W.; Bazzaz, F. A.; Booth, M. S.; Cleveland, C. C.; Collinge, S. K.; Dobson, A. P.; Epstein, P. R.; Holland, E. A.; Keeney, D. R.; Mallin, M. A.; Rogers, C. A.; Wayne, P.; Wolfe, A. H. (Wiley, 2003-06-01)
    Changes to the global nitrogen cycle affect human health well beyond the associated benefits of increased food production. Many intensively fertilized crops become animal feed, helping to create disparities in world food ...
  • Toward a better understanding and quantification of methane emissions from shale gas development 

    Caulton, D.R.; Shepson, P. B.; Santoro, R.L.; Sparks, J.P.; Howarth, R. W.; Ingraffea, A.; Camaliza, M.O.; Sweeney, C.; Karion, A.; Davis, K.J.; Stirm, B.H.; Montzka, S.A.; Miller, B. (National Academy of Sciences, 2014-04-29)
    The identification and quantification of methane emissions from natural gas production has become increasingly important owing to the increase in the natural gas component of the energy sector. An instrumented aircraft ...
  • Sulfur and carbon isotopes as tracers of salt-marsh organic matter flow 

    Peterson, B.J.; Howarth, R. W.; Garritt, R.H. (Wiley, 1986-08-01)
    Stable isotopes of sulfur and carbon were used to trace the dominant flows of organic matter from producers to macroconsumers in Great Sippewissett Salt Marsh on Cape Cod. Spartina alterniflora and sulfur-oxidizing bacteria ...
  • Nitrogen biogeochemistry of an urban rooftop farm 

    Harada, Y.; Whitlow, T.H.; Templer, P.H.; Howarth, R. W.; Walter, M.T.; Bassuk, N.L.; Russell-Anelli, J.H. (Frontiers Media S.A., 2018-10-11)
    Intensive agriculture represents a recent extension of green roof technology. Perceived ecosystem services provided by rooftop farming include stormwater management and the production of affordable and nutritious vegetables ...
  • A century of legacy phosphorus dynamics in a large drainage basin 

    McCrackin, M. L.; Muller-Karulis, B.; Gustafsson, B. G.; Howarth, R. W.; Humborg, C.; Svanbäck, A.; Swaney, D. P. (Wiley, 2018-06-27)
    There is growing evidence that the release of phosphorus (P) from “legacy” stores can frustrate efforts to reduce P loading to surface water from sources such as agriculture and human sewage. Less is known, however, about ...
  • Nutrient limitation of phytoplankton growth in Vineyard Sound and Oyster Pond, Falmouth, Massachusetts 

    Weber, C. F.; Barron, S.; Marino, R. M.; Howarth, R. W.; Tomasky, G.; Davidson, E. A. (University of Chicago Press, 2002-10)
    Intensive agriculture represents a recent extension of green roof technology. Perceived ecosystem services provided by rooftop farming include stormwater management and the production of affordable and nutritious vegetables ...
  • Coupled biogeochemical cycles: eutrophication and hypoxia in temperate estuaries and coastal marine ecosystems 

    Howarth, R. W.; Chan, F.; Conley, D. J.; Garnier, J.; Doney, S. C.; Marino, R. M.; Billen, G. (Wiley, 2011-02-01)
    Nutrient fluxes to coastal areas have risen in recent decades, leading to widespread hypoxia and other ecological damage, particularly from nitrogen (N). Several factors make N more limiting in estuaries and coastal waters ...
  • Greenhouse gas emissions from domestic hot water: heat pumps compared to most commonly used systems 

    Hong, B.; Howarth, R. W. (Wiley, 2016-01-25)
    We estimate the emissions of the two most important greenhouse gasses (GHG), carbon dioxide (CO2) and methane (CH4), from the use of modern high-efficiency heat pump water heaters compared to the most commonly used domestic ...

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