Method for Long-term Estimating Ice Algae Biomass Based on Spectral Attenuation Characteristics of the Sea Ice

A total of 135 bacterial strains were isolated from congelation (land fast) sea ice samples and ice algae biomass samples obtained from the coastal areas of the Vestfold Hills in East Antarctica (68°S, 78°E) during the summers of 1992–95. The sea ice isolates, along with reference strains. were analysed by numerical taxonomy and for DNA base composition in order to determine the biodiversity of sea ice bacteria. From these analyses 22 clusters of strains (phena) were obtained with most phena apparently representing novel bacterial taxa. The sea ice isolates could be categorized into three groups based on their ecophysiology: 1) slightly halophilic, psychrophilic bacteria often possessing fastidious growth requirements and which were predominantly isolated from sea ice algae biomass or from algae-rich ice samples; 2) halotolerant and psychrotolerant bacteria; and 3) non-halophilic bacteria isolated primarily from upper sections of congelation ice and other ice samples with low levcls of algal biomass.

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Brief Communication: Capturing scales of spatial heterogeneity of Antarctic sea ice algae communities

10.5194/tc-2016-186 ◽

2016 ◽

Cited By ~ 2

Author(s):

Alexander L. Forrest ◽

Lars C. Lund-Hansen ◽

Brian K. Sorrell ◽

Isak Bowden-Floyd ◽

Vanessa Lucieer ◽

...

Keyword(s):

Sea Ice ◽

Spatial Heterogeneity ◽

First Year ◽

Ice Algae ◽

Ecosystem Response ◽

Algae Biomass ◽

Sea Ice Algae ◽

Antarctic Sea Ice ◽

Spectral Bands ◽

Antarctic Waters

Abstract. Identifying spatial heterogeneity of sea ice algae communities is critical to predicting ecosystem response under future climate scenarios. Using an autonomous robotic sampling platform beneath sea ice in McMurdo Sound, Antarctica, we measured irradiance in spectral bands expected to describe the spatial heterogeneity. Derived estimates of ice algae biomass identified patchiness at length scales varying from 50–70 m under first-year sea ice. These results demonstrate that a step-change in how these communities can be assessed and monitored. The developed methodologies could be subsequently refined to further categorize different ice algae communities and their associated productivity in both Arctic and Antarctic waters.

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Towards improved estimates of sea-ice algal biomass: experimental assessment of hyperspectral imaging cameras for under-ice studies

Annals of Glaciology ◽

10.1017/aog.2017.6 ◽

2017 ◽

Vol 58 (75pt1) ◽

pp. 68-77 ◽

Cited By ~ 5

Author(s):

Emiliano Cimoli ◽

Arko Lucieer ◽

Klaus M. Meiners ◽

Lars Chresten Lund-Hansen ◽

Fraser Kennedy ◽

...

Keyword(s):

Sea Ice ◽

Hyperspectral Imaging ◽

Algal Biomass ◽

Large Scale ◽

Polar Regions ◽

Ice Algae ◽

Water Interface ◽

Algae Biomass ◽

Distribution Matching ◽

Ice Water

ABSTRACTIce algae are a key component in polar marine food webs and have an active role in large-scale biogeochemical cycles. They remain extremely under-sampled due to the coarse nature of traditional point sampling methods compounded by the general logistical limitations of surveying in polar regions. This study provides a first assessment of hyperspectral imaging as an under-ice remote-sensing method to capture sea-ice algae biomass spatial variability at the ice/water interface. Ice-algal cultures were inoculated in a unique inverted sea-ice simulation tank at increasing concentrations over designated cylinder enclosures and sparsely across the ice/water interface. Hyperspectral images of the sea ice were acquired with a pushbroom sensor attaining 0.9 mm square pixel spatial resolution for three different spectral resolutions (1.7, 3.4, 6.7 nm). Image analysis revealed biomass distribution matching the inoculated chlorophyll a concentrations within each cylinder. While spectral resolutions >6 nm hindered biomass differentiation, 1.7 and 3.4 nm were able to resolve spatial variation in ice algal biomass implying a coherent sensor selection. The inverted ice tank provided a suitable sea-ice analogue platform for testing key parameters of the methodology. The results highlight the potential of hyperspectral imaging to capture sea-ice algal biomass variability at unprecedented scales in a non-invasive way.

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An Under-Ice Hyperspectral and RGB Imaging System to Capture Fine-Scale Biophysical Properties of Sea Ice

Remote Sensing ◽

10.3390/rs11232860 ◽

2019 ◽

Vol 11 (23) ◽

pp. 2860 ◽

Cited By ~ 4

Author(s):

Emiliano Cimoli ◽

Klaus M. Meiners ◽

Arko Lucieer ◽

Vanessa Lucieer

Keyword(s):

Sea Ice ◽

Algal Biomass ◽

Bottom Topography ◽

Environmental Drivers ◽

Future Research ◽

Ice Algae ◽

Digital Photogrammetry ◽

Biophysical Properties ◽

Algae Biomass ◽

Non Invasive

Sea-ice biophysical properties are characterized by high spatio-temporal variability ranging from the meso- to the millimeter scale. Ice coring is a common yet coarse point sampling technique that struggles to capture such variability in a non-invasive manner. This hinders quantification and understanding of ice algae biomass patchiness and its complex interaction with some of its sea ice physical drivers. In response to these limitations, a novel under-ice sled system was designed to capture proxies of biomass together with 3D models of bottom topography of land-fast sea-ice. This system couples a pushbroom hyperspectral imaging (HI) sensor with a standard digital RGB camera and was trialed at Cape Evans, Antarctica. HI aims to quantify per-pixel chlorophyll-a content and other ice algae biological properties at the ice-water interface based on light transmitted through the ice. RGB imagery processed with digital photogrammetry aims to capture under-ice structure and topography. Results from a 20 m transect capturing a 0.61 m wide swath at sub-mm spatial resolution are presented. We outline the technical and logistical approach taken and provide recommendations for future deployments and developments of similar systems. A preliminary transect subsample was processed using both established and novel under-ice bio-optical indices (e.g., normalized difference indexes and the area normalized by the maximal band depth) and explorative analyses (e.g., principal component analyses) to establish proxies of algal biomass. This first deployment of HI and digital photogrammetry under-ice provides a proof-of-concept of a novel methodology capable of delivering non-invasive and highly resolved estimates of ice algal biomass in-situ, together with some of its environmental drivers. Nonetheless, various challenges and limitations remain before our method can be adopted across a range of sea-ice conditions. Our work concludes with suggested solutions to these challenges and proposes further method and system developments for future research.

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Variability of snow and ice thermal, physical and optical properties pertinent to sea ice algae biomass during spring

Journal of Marine Systems ◽

10.1016/j.jmarsys.2005.07.003 ◽

2005 ◽

Vol 58 (3-4) ◽

pp. 107-120 ◽

Cited By ~ 101

Author(s):

C.J. Mundy ◽

D.G. Barber ◽

C. Michel

Keyword(s):

Optical Properties ◽

Sea Ice ◽

Ice Algae ◽

Algae Biomass ◽

Sea Ice Algae ◽

Snow And Ice

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Vulnerability of the North Water ecosystem to climate change

Nature Communications ◽

10.1038/s41467-021-24742-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Sofia Ribeiro ◽

Audrey Limoges ◽

Guillaume Massé ◽

Kasper L. Johansen ◽

William Colgan ◽

...

Keyword(s):

Climate Change ◽

Sea Ice ◽

Late Holocene ◽

Sediment Cores ◽

Arctic Ecosystems ◽

Little Auk ◽

The North ◽

Water Ecosystem ◽

North Water

AbstractHigh Arctic ecosystems and Indigenous livelihoods are tightly linked and exposed to climate change, yet assessing their sensitivity requires a long-term perspective. Here, we assess the vulnerability of the North Water polynya, a unique seaice ecosystem that sustains the world’s northernmost Inuit communities and several keystone Arctic species. We reconstruct mid-to-late Holocene changes in sea ice, marine primary production, and little auk colony dynamics through multi-proxy analysis of marine and lake sediment cores. Our results suggest a productive ecosystem by 4400–4200 cal yrs b2k coincident with the arrival of the first humans in Greenland. Climate forcing during the late Holocene, leading to periods of polynya instability and marine productivity decline, is strikingly coeval with the human abandonment of Greenland from c. 2200–1200 cal yrs b2k. Our long-term perspective highlights the future decline of the North Water ecosystem, due to climate warming and changing sea-ice conditions, as an important climate change risk.

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Dark metabolism: a molecular insight into how the Antarctic sea‐ice diatom Fragilariopsis cylindrus survives long‐term darkness

New Phytologist ◽

10.1111/nph.15843 ◽

2019 ◽

Vol 223 (2) ◽

pp. 675-691 ◽

Cited By ~ 10

Author(s):

Fraser Kennedy ◽

Andrew Martin ◽

John P. Bowman ◽

Richard Wilson ◽

Andrew McMinn

Keyword(s):

Sea Ice ◽

Antarctic Sea Ice ◽

Fragilariopsis Cylindrus ◽

Dark Metabolism ◽

The Antarctic ◽

Insight Into

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Windows in Arctic sea ice: Light transmission and ice algae in a refrozen lead

Journal of Geophysical Research Biogeosciences ◽

10.1002/2016jg003626 ◽

2017 ◽

Vol 122 (6) ◽

pp. 1486-1505 ◽

Cited By ~ 25

Author(s):

Hanna M. Kauko ◽

Torbjørn Taskjelle ◽

Philipp Assmy ◽

Alexey K. Pavlov ◽

C. J. Mundy ◽

...

Keyword(s):

Sea Ice ◽

Light Transmission ◽

Arctic Sea Ice ◽

Ice Algae ◽

Arctic Sea

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The implications of selected processing methods on satellite altimetry derived sea ice thickness state and trends in the seasonal ice zone

10.5194/egusphere-egu21-12240 ◽

2021 ◽

Author(s):

Isolde Glissenaar ◽

Jack Landy ◽

Alek Petty ◽

Nathan Kurtz ◽

Julienne Stroeve

Keyword(s):

Sea Ice ◽

Snow Depth ◽

Satellite Altimetry ◽

Region Of Interest ◽

The Arctic ◽

Ice Thickness ◽

Sea Ice Thickness ◽

Baffin Bay ◽

The Impact

The ice cover of the Arctic Ocean is increasingly becoming dominated by seasonal sea ice. It is important to focus on the processing of altimetry ice thickness data in thinner seasonal ice regions to understand seasonal sea ice behaviour better. This study focusses on Baffin Bay as a region of interest to study seasonal ice behaviour.We aim to reconcile the spring sea ice thickness derived from multiple satellite altimetry sensors and sea ice charts in Baffin Bay and produce a robust long-term record (2003-2020) for analysing trends in sea ice thickness. We investigate the impact of choosing different snow depth products (the Warren climatology, a passive microwave snow depth product and modelled snow depth from reanalysis data) and snow redistribution methods (a sigmoidal function and an empirical piecewise function) to retrieve sea ice thickness from satellite altimetry sea ice freeboard data.The choice of snow depth product and redistribution method results in an uncertainty envelope around the March mean sea ice thickness in Baffin Bay of 10%. Moreover, the sea ice thickness trend ranges from -15 cm/dec to 20 cm/dec depending on the applied snow depth product and redistribution method. Previous studies have shown a possible long-term asymmetrical trend in sea ice thinning in Baffin Bay. The present study shows that whether a significant long-term asymmetrical trend was found depends on the choice of snow depth product and redistribution method. The satellite altimetry sea ice thickness results with different snow depth products and snow redistribution methods show that different processing techniques can lead to different results and can influence conclusions on total and spatial sea ice thickness trends. Further processing work on the historic radar altimetry record is needed to create reliable sea ice thickness products in the marginal ice zone.

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Impact of the B-15 iceberg “stranding event” on the physical and biological properties of sea ice in McMurdo Sound, Ross Sea, Antarctica

Antarctic Science ◽

10.1017/s0954102008001284 ◽

2008 ◽

Vol 20 (6) ◽

pp. 593-604 ◽

Cited By ~ 21

Author(s):

J.-P. Remy ◽

S. Becquevort ◽

T.G. Haskell ◽

J.-L. Tison

Keyword(s):

Sea Ice ◽

Ross Sea ◽

Ice Cores ◽

Ice Cover ◽

Biological Properties ◽

Trophic Relationships ◽

Oceanic Circulation ◽

Mcmurdo Sound ◽

Algae Biomass ◽

Second Year

AbstractIce cores were sampled at four stations in McMurdo Sound (Ross Sea) between 1999 and 2003. At the beginning of year 2000, a very large iceberg (B-15) detached itself from the Ross Ice Shelf and stranded at the entrance of the Sound, preventing the usual oceanic circulation purging of the annual sea ice cover from this area. Ice textural studies showed that a second year sea ice cover was built-up at three out of the four stations: ice thickness increased to about 3 m. Repeated alternation of columnar and platelet ice appeared, and bulk salinity showed a strong decrease, principally in the upper part of the ice sheet, with associated brine volume decrease. Physical modification influenced the biology as well. By decreasing the light and space available for organisms in the sea ice cover, the stranding of B-15 has i) hampered autotrophic productivity, with chlorophyllaconcentration and algae biomass significantly lower for second year ice stations, and ii) affected trophic relationships such as the bacterial biomass/chlaconcentration correlation, or the autotrophic to heterotrophic ratio.

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