The Expansion of Low Oxygen Zones in the Global Ocean and Coastal Waters

Date: 2019-02-21

Time: 09:00 - 16:40

Address: Lilla Frescativägen 4A Stockholm

Venue: Beijer Hall, Royal Swedish Academy of Sciences

Host:  The Environmental Committee of the Royal Swedish Academy of Sciences. The symposium is now available as video.

Watch the other lectures from the symposium at our YouTube channel

Oxygen concentrations in both the global ocean and coastal waters have been declining since at least the middle of the 20th century. This oxygen loss is one of the most important changes occurring in an ocean increasingly modified by human activities that have raised temperatures, CO2 levels, and increased nutrient inputs that have altered the abundances and distributions of marine species. Oxygen is naturally low or absent where biological oxygen consumption through respiration exceeds the rate of oxygen supplied by physical transport, air-sea fluxes, and photosynthesis. The enhanced production in surface waters of the coastal zone from nutrient inputs from sewage and agricultural activities increases the delivery rate of degradable organic matter to bottom waters where microbial decomposition by aerobic respiration consumes oxygen. In addition, ocean warming reduces the solubility of oxygen and raises metabolic rates also accelerating the rate of oxygen consumption. Under current trajectories, anthropogenic activities could drive the ocean toward widespread oxygen deficiency within the next thousand years. The symposium will address the impact of changes in productivity, biodiversity, and biogeochemical cycles with declining oxygen in the global ocean and coastal waters.

Lectures by

  • Denise Breitburg, Smithsonian Environmental Research Center, USA
  • Jacob Carstensen, Aarhus University, Denmark
  • Daniel J. Conley, The Environmental Committee, The Royal Swedish Academy of Sciences, Sweden
  • Christoph Humborg, Stockholm University, Sweden
  • Alf Norkko, University of Helsinki, Finland
  • Andreas Oschlies, GEOMAR Helmholtz Centre for Ocean Research Kiel, Germany
  • Bess B. Ward, Princeton University, USA

The symposium is free of charge and open to the public but registration is required for all participants. Limited number of seats.  Please state eventual food preferences or allergies in the registration form.

Programme and abstracts

This symposium is funded by Baltic Sea Centre at Stockholm University, BalticSea2020, the Swedish Agency for Marine and Water Management and the Royal Swedish Academy of Sciences.

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