Th isotopes in the Santa Monica basin: Temporal variation, long-term mass balance and model rate constants

Abstract GRACE and ICESat Antarctic mass-balance differences are resolved utilizing their dependencies on corrections for changes in mass and volume of the same underlying mantle material forced by ice-loading changes. Modeled gravimetry corrections are 5.22 times altimetry corrections over East Antarctica (EA) and 4.51 times over West Antarctica (WA), with inferred mantle densities 4.75 and 4.11 g cm−3. Derived sensitivities (Sg, Sa) to bedrock motion enable calculation of motion (δB0) needed to equalize GRACE and ICESat mass changes during 2003–08. For EA, δB0 is −2.2 mm a−1 subsidence with mass matching at 150 Gt a−1, inland WA is −3.5 mm a−1 at 66 Gt a−1, and coastal WA is only −0.35 mm a−1 at −95 Gt a−1. WA subsidence is attributed to low mantle viscosity with faster responses to post-LGM deglaciation and to ice growth during Holocene grounding-line readvance. EA subsidence is attributed to Holocene dynamic thickening. With Antarctic Peninsula loss of −26 Gt a−1, the Antarctic total gain is 95 ± 25 Gt a−1 during 2003–08, compared to 144 ± 61 Gt a−1 from ERS1/2 during 1992–2001. Beginning in 2009, large increases in coastal WA dynamic losses overcame long-term EA and inland WA gains bringing Antarctica close to balance at −12 ± 64 Gt a−1 by 2012–16.

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Long-term mass balance of perennial firn and ice in an Alpine cave (Austria): Constraints from radiocarbon-dated wood fragments

The Holocene ◽

10.1177/0959683613515729 ◽

2013 ◽

Vol 24 (2) ◽

pp. 165-175 ◽

Cited By ~ 14

Author(s):

Christoph Spötl ◽

Paula J Reimer ◽

Marc Luetscher

Keyword(s):

Mass Balance

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Long-Term Spatio-Temporal Variation in Runoff Curve Number under Consistent Cover Conditions: a Southeastern US Case Study

Water Resources Management ◽

10.1007/s11269-017-1680-z ◽

2017 ◽

Vol 31 (11) ◽

pp. 3491-3505 ◽

Cited By ~ 1

Author(s):

D. R. Edwards

Keyword(s):

Temporal Variation ◽

Curve Number ◽

Southeastern Us ◽

Runoff Curve Number ◽

Spatio Temporal

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Long-term mass balance of selected polythermal glaciers on Spitsbergen, Svalbard

Norsk Geografisk Tidsskrift - Norwegian Journal of Geography ◽

10.1080/00291959608552352 ◽

1996 ◽

Vol 50 (1) ◽

pp. 55-66 ◽

Cited By ~ 9

Author(s):

Bernd Etzelmoüller ◽

Johan L. Sollid

Keyword(s):

Mass Balance

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The Importance of Variables and Parameters in Radiolytic Chemical Kinetics Modeling

MRS Proceedings ◽

10.1557/proc-127-905 ◽

1988 ◽

Vol 127 ◽

Author(s):

M. G. Piepho ◽

P. J. Turner ◽

P. W. Reimus

Keyword(s):

Chemical Kinetics ◽

Rate Constants ◽

Transient Species ◽

Geologic Repository ◽

Species Concentration ◽

Waste Package ◽

Long Term Performance ◽

Term Performance ◽

Over Time

ABSTRACTRadiolysis may significantly affect the long-term performance of nuclear waste packages in a geologic repository. Radiolysis of available moisture and air in an unsaturated or saturated environment will create transient species that can significantly change the pH and/or Eh of the available moisture. These changes can influence rates of containment corrosion, waste form dissolution, and radionuclide solubilities and transport.Many of the pertinent radiochemical reactions are not completely understood, and most of the associated rate constants are poorly characterized. To help identify the important radiochemical reactions, rate constants, species, and environmental conditions, an importance theory code, SWATS (Sensitivity With Adjoint Theory-Sparse version)-LOOPCHEM, has been developed for the radiolytic chemical kinetics model in the radiolysis code LOOPCHEM. The LOOPCHEM code calculates the concentrations of various species in a radiolytic field over time. The SWATS-LOOPCHEM code efficiently calculates: 1) the importance (relative to a defined response of interest) of each species concentration over time, 2) the sensitivity of each parameter of interest, and 3) the importance of each equation in the radiolysis model. The calculated results will be used to guide future experimental and modeling work for determining the importance of radiolysis on waste package performance. A demonstration (the importance of selected concentrations and the sensitivities of selected parameters) of the SWATS-LOOPCHEM code is provided for illustrative purposes, and no attempt is made at this time to interpret the results for waste package performance assessment purposes.

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Eco-evolutionary feedbacks promote fluctuating selection and long-term stability of antagonistic networks

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2017.2596 ◽

2018 ◽

Vol 285 (1874) ◽

pp. 20172596 ◽

Cited By ~ 10

Author(s):

Cecilia Siliansky de Andreazzi ◽

Paulo R. Guimarães ◽

Carlos J. Melián

Keyword(s):

Temporal Variation ◽

Evolutionary Dynamics ◽

Species Interaction ◽

Fluctuating Selection ◽

Term Stability ◽

Long Term Stability ◽

Interacting Species ◽

Species Abundances ◽

Antagonistic Interactions

Studies have shown the potential for rapid adaptation in coevolving populations and that the structure of species interaction networks can modulate the vulnerability of ecological systems to perturbations. Although the feedback loop between population dynamics and coevolution of traits is crucial for understanding long-term stability in ecological assemblages, modelling eco-evolutionary dynamics in species-rich assemblages is still a challenge. We explore how eco-evolutionary feedbacks influence trait evolution and species abundances in 23 empirical antagonistic networks. We show that, if selection due to antagonistic interactions is stronger than other selective pressures, eco-evolutionary feedbacks lead to higher mean species abundances and lower temporal variation in abundances. By contrast, strong selection of antagonistic interactions leads to higher temporal variation of traits and on interaction strengths. Our results present a theoretical link between the study of the species persistence and coevolution in networks of interacting species, pointing out the ways by which coevolution may decrease the vulnerability of species within antagonistic networks to demographic fluctuation.

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