scholarly journals Demographic, ecological, and physiological responses of ringed seals to an abrupt decline in sea ice availability

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e2957 ◽  
Author(s):  
Steven H. Ferguson ◽  
Brent G. Young ◽  
David J. Yurkowski ◽  
Randi Anderson ◽  
Cornelia Willing ◽  
...  
Keyword(s):  
Sea Ice ◽  
Body Condition ◽  
Large Scale ◽  
Southern Oscillation ◽  
High Stress ◽  
Open Water ◽  
Hudson Bay ◽  
Ice Dynamics ◽  
Southern Limit ◽  
Sea Ice Dynamics

To assess whether demographic declines of Arctic species at the southern limit of their range will be gradual or punctuated, we compared large-scale environmental patterns including sea ice dynamics to ringed seal (Pusa hispida) reproduction, body condition, recruitment, and stress in Hudson Bay from 2003 to 2013. Aerial surveys suggested a gradual decline in seal density from 1995 to 2013, with the lowest density occurring in 2013. Body condition decreased and stress (cortisol) increased over time in relation to longer open water periods. The 2010 open water period in Hudson Bay coincided with extremes in large-scale atmospheric patterns (North Atlantic Oscillation, Arctic Oscillation, El Nino-Southern Oscillation) resulting in the earliest spring breakup and the latest ice formation on record. The warming event was coincident with high stress level, low ovulation rate, low pregnancy rate, few pups in the Inuit harvest, and observations of sick seals. Results provide evidence of changes in the condition of Arctic marine mammals in relation to climate mediated sea ice dynamics. We conclude that although negative demographic responses of Hudson Bay seals are occurring gradually with diminishing sea ice, a recent episodic environmental event played a significant role in a punctuated population decline.

scholarly journals Demographic, ecological and physiological responses of ringed seals to an abrupt decline in sea ice availability

2016 ◽  
Author(s):  
Steven H Ferguson ◽  
Brent G Young ◽  
David J Yurkowski ◽  
Randi Anderson ◽  
Cornelia Willing ◽  
...  
Keyword(s):  
Sea Ice ◽  
Body Condition ◽  
Large Scale ◽  
Population Decline ◽  
Open Water ◽  
Hudson Bay ◽  
Ice Dynamics ◽  
Southern Limit ◽  
Environmental Event ◽  
Sea Ice Dynamics

To assess whether demographic declines of Arctic species at the southern limit of their range will be gradual or punctuated, we compared large-scale environmental patterns including sea ice dynamics to ringed seal (Pusa hispida ) reproduction, body condition, recruitment, and stress in Hudson Bay from 2003-2013. Aerial surveys suggested a gradual decline in seal density from 1995-2013, with the lowest density occurring in 2013. Body condition decreased and stress (cortisol) increased over time in relation to longer open waterperiods. The 2010 open water period in Hudson Bay coincided with extremes in large-scale atmospheric patterns (NAO, AO, ENSO) resulting in the earliest spring breakup and the latest ice formation on record. The warming event was coincident with the highest stress levels and the lowest recorded ovulation rate and low pregnancy rate, few pups in the Inuit harvest, and observations of sick seals. We conclude that although negative demographic responses of Hudson Bay seals are occurring gradually with diminishing sea ice, a recent episodic environmental event played a significant role in a punctuated population decline.

scholarly journals Demographic, ecological and physiological responses of ringed seals to an abrupt decline in sea ice availability

2016 ◽  
Author(s):  
Steven H Ferguson ◽  
Brent G Young ◽  
David J Yurkowski ◽  
Randi Anderson ◽  
Cornelia Willing ◽  
...  
Keyword(s):  
Sea Ice ◽  
Body Condition ◽  
Large Scale ◽  
Population Decline ◽  
Open Water ◽  
Hudson Bay ◽  
Ice Dynamics ◽  
Southern Limit ◽  
Environmental Event ◽  
Sea Ice Dynamics

To assess whether demographic declines of Arctic species at the southern limit of their range will be gradual or punctuated, we compared large-scale environmental patterns including sea ice dynamics to ringed seal (Pusa hispida ) reproduction, body condition, recruitment, and stress in Hudson Bay from 2003-2013. Aerial surveys suggested a gradual decline in seal density from 1995-2013, with the lowest density occurring in 2013. Body condition decreased and stress (cortisol) increased over time in relation to longer open waterperiods. The 2010 open water period in Hudson Bay coincided with extremes in large-scale atmospheric patterns (NAO, AO, ENSO) resulting in the earliest spring breakup and the latest ice formation on record. The warming event was coincident with the highest stress levels and the lowest recorded ovulation rate and low pregnancy rate, few pups in the Inuit harvest, and observations of sick seals. We conclude that although negative demographic responses of Hudson Bay seals are occurring gradually with diminishing sea ice, a recent episodic environmental event played a significant role in a punctuated population decline.

scholarly journals Results from the implementation of the elastic viscous plastic sea ice rheology in HadCM3

2006 ◽  
Vol 3 (4) ◽  
pp. 777-803
Author(s):  
W. Connolley ◽  
A. Keen ◽  
A. McLaren
Keyword(s):  
Sea Ice ◽  
Large Scale ◽  
Climate Model ◽  
Ice Dynamics ◽  
Sea Ice Dynamics ◽  
Future Improvement ◽  
Physically Based ◽  
Solid Foundation ◽  
Hadley Centre ◽  
Better Than

Abstract. We present results of an implementation of the Elastic Viscous Plastic (EVP) sea ice dynamics scheme into the Hadley Centre coupled ocean-atmosphere climate model HadCM3. Although the large-scale simulation of sea ice in HadCM3 is quite good with this model, the lack of a full dynamical model leads to errors in the detailed representation of sea ice and limits our confidence in its future predictions. We find that introducing the EVP scheme results in a worse initial simulation of the sea ice. This paper documents various improvements made to improve the simulation, resulting in a sea ice simulation that is better than the original HadCM3 scheme overall. Importantly, it is more physically based and provides a more solid foundation for future improvement. We then consider the interannual variability of the sea ice in the new model and demonstrate improvements over the HadCM3 simulation.

scholarly journals On a Simple Sea-Ice Dynamics Model for Climate Studies

1990 ◽  
Vol 14 ◽  
pp. 72-77 ◽  
Author(s):  
G.M. Flato ◽  
W.D. Hibler
Keyword(s):  
Sea Ice ◽  
Large Scale ◽  
Wind Fields ◽  
Fluid Approximation ◽  
Ice Dynamics ◽  
Monthly Average ◽  
Sea Ice Dynamics ◽  
Average Wind ◽  
Cavitating Fluid ◽  
Climate Studies

Sea-ice motion and dynamic thickness build-up play an important role in the transfer of heat between the ocean and the atmosphere and so must be included in large-scale climate studies. A “cavitating-fluid” approximation allows these dynamic processes to be parameterized in a simple way by ignoring shear and tensile strength yet retaining compressive strength. A simple procedure for approximating a cavitating fluid is presented here and is compared to the more complete viscous-plastic sea-ice model by performing several three year simulations with daily varying and monthly average wind forcing. Although differences exist on a monthly basis, the two models compare favourably over a seasonal cycle, particularly when compared to a thermodynamics only model in which ice motion is ignored. The lack of shear strength in a cavitating-fluid approximation makes it less sensitive to smoothing of the wind fields (as demonstrated by the monthly average wind simulations); however it also changes the detailed circulation and thickness build-up patterns somewhat. Overall, the cavitating-fluid approximation shows considerable promise for including sea-ice dynamics in large-scale climate models, especially where averaged wind fields are employed.

scholarly journals Results from the implementation of the Elastic Viscous Plastic sea ice rheology in HadCM3

Ocean Science ◽  
2006 ◽  
Vol 2 (2) ◽  
pp. 201-211 ◽  
Author(s):  
W. M. Connolley ◽  
A. B. Keen ◽  
A. J. McLaren
Keyword(s):  
Sea Ice ◽  
Large Scale ◽  
Climate Model ◽  
Ice Dynamics ◽  
Sea Ice Dynamics ◽  
Ocean Atmosphere ◽  
Physically Based ◽  
Solid Foundation ◽  
Hadley Centre ◽  
Better Than

Abstract. We present results of an implementation of the Elastic Viscous Plastic (EVP) sea ice dynamics scheme into the Hadley Centre coupled ocean-atmosphere climate model HadCM3. Although the large-scale simulation of sea ice in HadCM3 is quite good with this model, the lack of a full dynamical model leads to errors in the detailed representation of sea ice and limits our confidence in its future predictions. We find that introducing the EVP scheme results in a worse initial simulation of the sea ice. This paper documents various enhancements made to improve the simulation, resulting in a sea ice simulation that is better than the original HadCM3 scheme overall. Importantly, it is more physically based and provides a more solid foundation for future development. We then consider the interannual variability of the sea ice in the new model and demonstrate improvements over the HadCM3 simulation.

scholarly journals IcePAC – a Probabilistic Tool to Study Sea Ice Spatiotemporal Dynamic: Application to the Hudson Bay area, Northeastern Canada

2018 ◽  
Author(s):  
Charles Gignac ◽  
Monique Bernier ◽  
Karem Chokmani
Keyword(s):  
Sea Ice ◽  
Numerical Models ◽  
Hudson Bay ◽  
Ice Dynamics ◽  
Probabilistic Information ◽  
Bay Area ◽  
Sea Ice Dynamics ◽  
Ice Conditions ◽  
Reliable Knowledge ◽  
Informative Content

Abstract. A reliable knowledge and assessment of the sea ice conditions and their evolution in time is a priority for numerous decision makers in the domains of coastal and offshore management and engineering as well as in commercial navigation. As of today, countless research projects aimed at both modelling and mapping past, actual and future sea ice conditions were realized using sea ice numerical models, statistical models, educated guesses or remote sensing imagery. From these research, reliable information helping to understand sea ice evolution in space and in time are available to stakeholders. However, no research has, as of today, assessed the evolution of the sea ice cover with a frequency modelling approach, by identifying the underlying theoretical distribution describing the sea ice behaviour at a given point in space and time. This project suggests the development of a probabilistic tool, named IcePAC, based on frequency modelling of historical 1978–2015 passive microwave sea ice concentrations maps from EUMETSAT OSI-409 product, to study the sea ice spatiotemporal behaviour in the waters of the Hudson Bay System in Northeastern Canada. Pixel scale models are based on the generalized Beta distribution and generated at a weekly temporal resolution. Results showed coherent with the Canadian Ice Service 1980–2010 Sea Ice Climatic Atlas average freeze-up and meltdown dates for numerous coastal communities in the study area and showed that it is possible to evaluate a range of plausible events, such as the shortest and longest probable ice free season duration, for any given location on the simulation domain. This innovative research opens a path towards various analyses on sea ice dynamics that would gain in informative content and value by relying on the kind of probabilistic information and simulation data available from the IcePAC tool.

scholarly journals On a Simple Sea-Ice Dynamics Model for Climate Studies

1990 ◽  
Vol 14 ◽  
pp. 72-77 ◽  
Author(s):  
G.M. Flato ◽  
W.D. Hibler
Keyword(s):  
Sea Ice ◽  
Large Scale ◽  
Wind Fields ◽  
Fluid Approximation ◽  
Ice Dynamics ◽  
Monthly Average ◽  
Sea Ice Dynamics ◽  
Average Wind ◽  
Cavitating Fluid ◽  
Climate Studies

Sea-ice motion and dynamic thickness build-up play an important role in the transfer of heat between the ocean and the atmosphere and so must be included in large-scale climate studies. A “cavitating-fluid” approximation allows these dynamic processes to be parameterized in a simple way by ignoring shear and tensile strength yet retaining compressive strength. A simple procedure for approximating a cavitating fluid is presented here and is compared to the more complete viscous-plastic sea-ice model by performing several three year simulations with daily varying and monthly average wind forcing. Although differences exist on a monthly basis, the two models compare favourably over a seasonal cycle, particularly when compared to a thermodynamics only model in which ice motion is ignored. The lack of shear strength in a cavitating-fluid approximation makes it less sensitive to smoothing of the wind fields (as demonstrated by the monthly average wind simulations); however it also changes the detailed circulation and thickness build-up patterns somewhat. Overall, the cavitating-fluid approximation shows considerable promise for including sea-ice dynamics in large-scale climate models, especially where averaged wind fields are employed.

Mathematical features of Hibler's model of large-scale sea-ice dynamics

1995 ◽  
Vol 47 (3) ◽  
pp. 179-230 ◽  
Author(s):  
Eckhard Kleine ◽  
Sergey Sklyar
Keyword(s):  
Sea Ice ◽  
Large Scale ◽  
Ice Dynamics ◽  
Sea Ice Dynamics
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