Ocean quahogs (Arctica islandica) and Atlantic surfclams (Spisula solidissima) on the Mid-Atlantic Bight continental shelf and Georges Bank: The death assemblage as a recorder of climate change and the reorganization of the continental shelf benthos

AbstractAnnual growth bands of mollusk shells record several types of paleoenvironmental information, including geochemical proxies for water properties and morphological characteristics of growth and mortality. Sclerochronology, the marine counterpart of dendrochronology, offers a way to link individual shells together to form long continuous records of such parameters. It also allows for precise dating of recent shells and identification of contemporaneous fossil individuals. The longevity of the ocean quahog Arctica islandica (commonly >100 yr) makes this species well suited for sclerochronology. Band width records of contemporaneous A. islandica specimens from the same region exhibit high correlations (ρ = 0.60–0.80 for spans of ≥30 bands), indicating some common environmental influences on shell growth. By adopting several strict criteria, fossil (dead-collected) shells can be linked into composite sclerochronologies. A seven-shell 154-yr chronology was constructed for Georges Bank using three live-collected and four dead-collected shells. Band width matching indicates that the dead-collected individuals died in A.D. 1950, 1971, 1978, and 1989. Sclerochronological age assignments were verified using aspartic acid racemization dating. Construction of a 1000-yr sclerochronology is judged to be feasible using the described methods.

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Projecting the effects of climate change on Calanus finmarchicus distribution within the U.S. Northeast Continental Shelf

Scientific Reports ◽

10.1038/s41598-017-06524-1 ◽

2017 ◽

Vol 7 (1) ◽

Cited By ~ 19

Author(s):

Brian D. Grieve ◽

Jon A. Hare ◽

Vincent S. Saba

Keyword(s):

Climate Change ◽

Continental Shelf ◽

Calanus Finmarchicus ◽

The U.S

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Controls on oxygen response to climate change on the Northwest European Continental Shelf

10.5194/egusphere-egu2020-13393 ◽

2020 ◽

Author(s):

Sarah L. Wakelin ◽

Yuri Artioli ◽

Momme Butenschön ◽

Jason Holt ◽

Jeremy Blackford

Keyword(s):

Climate Change ◽

Continental Shelf ◽

Water Column ◽

Ecosystem Processes ◽

Phytoplankton Production ◽

Biogeochemical Model ◽

Biological Cycling ◽

Increasing Temperature ◽

The Impact ◽

Oxygen Concentrations

<p>Dissolved oxygen in the ocean is an indicator of water quality and low concentrations can threaten ecosystem health. The main sources of marine oxygen are diffusion from the atmosphere and phytoplankton photosynthesis. Biological respiration and decomposition act to reduce oxygen concentrations. Under conditions of vertical stratification, the water column below the pycnocline is isolated from oxygen exchange with the atmosphere, photosynthesis may be limited by light availability and oxygen concentrations decrease. Climate change influences the oxygen cycle in two ways: 1) changing the hydrodynamic climate and 2) affecting rates of biogeochemical processes. The hydrodynamic climate affects the nutrient supply and so controls phytoplankton production while changes to water column stratification affects vertical mixing. Gas solubility decreases with increasing temperature so that oxygen uptake from the atmosphere is expected to decrease under increasing oceanic temperatures. Biological cycling rates increase with increasing temperature affecting photosynthesis, respiration and bacterial decomposition. It is not obvious whether changes in oxygen concentrations due to changing ecosystem processes will mitigate or reinforce the projected reduction from solubility changes.</p><p>The Northwest European Continental shelf (NWES) is a region of the northeast Atlantic that experiences seasonal stratification. We use the physics-biogeochemical model NEMO-ERSEM to study near-bed oxygen concentrations on the NWES under a high greenhouse gas emissions scenario (Representative Concentration Pathway (RCP) 8.5). We show that much of the NWES could experience low oxygen concentrations by 2100 and assess the relative impacts of changing temperature and ecosystem processes. Until about 2040 the impact of solubility dominates the oxygen change. The mean near-bed oxygen concentration is projected to decrease by 6.3% by 2100, of which 73% is due to solubility changes and the remainder to changes in the ecosystem. In the oxygen-depleted region in the eastern North Sea, 77% of the near-bed oxygen reduction is due to ecosystem processes.</p>

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Transboundary chains for CCS : Allocation of rights and obl igations between the state parties within the climate regime

Journal for European Environmental & Planning Law ◽

10.1163/187601007x00307 ◽

2007 ◽

Vol 4 (5) ◽

pp. 367-377 ◽

Cited By ~ 1

Author(s):

Gustav Haver ◽

Hans Christian Bugge

Keyword(s):

Climate Change ◽

Continental Shelf ◽

Kyoto Protocol ◽

Carbon Capture ◽

Carbon Capture And Storage ◽

The State ◽

Climate Regime ◽

And Storage ◽

Geological Formations

AbstractThis article will discuss how transboundary chains for carbon capture and storage (CCS) relates to the rights and obligations of states pursuant to the UN Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol (Kyoto). We will discuss questions related to chains of CCS where CO2 is captured at an installation in one country, transported, and injected and stored in geological formations on the continental shelf of another country.1 How does the climate regime apply to such a CO2 chain"?

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