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Over the last few years a number of computational approaches have been developed that enable the optimisation of marine monitoring strategies for CCS. These include methods to: simulate and quantify hypothetical release events, identify highly sensitive criteria by which to distinguish anomalous biogeochemistry which may indicate a seep and define minimum deployments of monitoring platforms which guarantee an acceptable chance of detection. In order for these tools to be operationally useful it is necessary to place them in an accessible and integrated digital format that allows the methodologies to be applied coherently to multiple offshore storage sites and to answer specific stakeholder led questions around required sensitivity, cost and assurance levels. In this work we describe progress towards achieving this integration as well as the site specific data necessary to generate bespoke monitoring guidance.

In this review, we compile the evidence of lake and isolation basin sediments for the chronology of the last deglaciation along the coastal parts of eastern Greenland between 70°N and 83°N. Radiocarbon dates of remains of freshwater plants and bulk organic carbon extracted from lacustrine sediments suggest that the present day ice-free parts of eastern Greenland were not deglaciated prior to the early Holocene. Older dates do exist but must be used with caution due to possible contamination with old carbon. However, many inland locations in eastern North and central East Greenland became ice-free distinctly later between 10,000 and 7500 cal yr BP, depending on their relative position to the ice margin. This compilation confirms former suggestions that hitherto no secure Late glacial lacustrine sediments have been found in the ice-free parts of eastern Greenland. Late glacial sediments are only known from lakes in southern Greenland and from few marine locations off eastern Greenland. The here summarized lake sediment evidence for the last deglaciation supports the results of an earlier compilation of dates from marine shells. © 2007 Elsevier Ltd. All rights reserved.

A mid-Holocene climate optimum is inferred from a palaeosalinity reconstruction of a closed saline lake (Beall Lake) from the Windmill Islands, East Antarctica using an expanded diatom salinity weighted averaging (WA) regression and calibration model. The addition of 14 lakes and ponds from the Windmill Islands, East Antarctica, to an existing weighted averaging regression and calibration palaeosalinity model of 33 lakes from the Vestfold Hills, East Antarctica expands the number of taxa and lakes and the range of salinity in the existing model and improves the model's predictive ability. This improved model was used to infer Holocene changes in lake water salinity in Beall Lake, Windmill Islands. Six changes in diatom-inferred salinity in Beall Lake are put into broad chronological context based on three radiocarbon dates: as the East Antarctic Ice Sheet (EAIS) retreated from the Windmill Islands during the early Holocene (∼9000–8130 corr. yr BP), Beall Lake formed as a melt water-fed freshwater lake, which gradually became more saline as marine influence increased from ∼8000 corr. yr BP. Between ∼8000 and 4800 corr. yr BP, the diatom assemblage included planktonic marine taxa such as Chaetoceros spp. and cryophilic taxa such as Fragilariopsis cylindrus, which indicate favourable summer growth conditions. A mid-Holocene warm period produced a climate that was warmer and more humid with increased precipitation and snow accumulation. This is reflected in the Beall Lake core as a reduction in the salinity of the lake diatom assemblage from ∼4800–4600 corr. yr BP. Holocene isostatic uplift rates in the Windmill Islands vary from 5–6 m/1000 yr. By applying this uplift rate, it is calculated that the bedrock would have risen above sea level by ∼4000 yr BP. The Beall Lake core diatom assemblage from ∼4600–2900 corr. yr BP includes both marine cryophilic and planktonic taxa together with freshwater benthic and planktonic lacustrine taxa. This mix of species indicates the emergence of the lake from the sea around ∼4600 corr. yr BP. From ∼2800 corr. yr BP, retreat of the ice margin led to increasing melt water inputs and associated freshening of the lake basin until ∼1900 corr. yr BP. The lake basin had no oceanic influence by this time, allowing a terrestrial freshwater flora to establish and thrive for the next ∼1000 yr. At ∼1850 corr. yr BP, a sudden and rapid salinity change is evident in Beall Lake. A late Holocene warm period between 2000 and 1000 yr BP has been observed in ice core records from Law Dome (an ice cap abutting the Windmill Islands to the east and north). It is therefore inferred that, at ∼1850 corr. yr BP, summer temperatures within the Beall Lake catchment area were much higher than present summer temperatures. The climate optimum identified in the Beall Lake core ∼4800 yr BP confirms mid-Holocene warming of the Windmill Islands and suggests a synchronous mid-Holocene climate optimum occurred across coastal East Antarctica. In addition, the abrupt climate change inferred at ∼1850 yr BP suggests that higher resolution sampling of sediment cores from coastal East Antarctic limnological oases will provide more evidence of rapid climate change events over coastal East Antarctica in future.

The late Quaternary palaeoenvironmental history of the southern Windmill Islands, East Antarctica, has been reconstructed using diatom assemblages from two long, well-dated sediment cores taken in two marine bays. The diatom assemblage of the lowest sediment layers suggests a warm climate with mostly open water conditions during the late Pleistocene. During the following glacial, the Windmill Islands were covered by grounded ice preventing any in situ bioproductivity. Following deglaciation, a sapropel with a well-preserved diatom assemblage was deposited from ∼10 500 cal yr BP. Between ∼10 500 and ∼4000 cal yr BP, total organic carbon (Corg) and total diatom valve concentrations as well as the diatom species composition suggest relatively cool summer temperatures. Hydrological conditions in coastal bays were characterised by combined winter sea-ice and open water conditions. This extensive period of glacial retreat was followed by the Holocene optimum (∼4000 to ∼1000 cal yr BP), which occurred later in the southern Windmill Islands than in most other Antarctic coastal regions. Diatom assemblages in this period suggest ice-free conditions and meltwater-stratified waters in the marine bays during summer, which is also reflected in high proportions of freshwater diatoms in the sediments. The diatom assemblage in the upper sediments of both cores indicates Neoglacial cooling from ∼1000 cal yr BP, which again led to seasonally persistent sea-ice on the bays. The Holocene optimum and cooling trends in the Windmill Islands did not occur contemporaneously with other Antarctic coastal regions, showing that the here presented record reflects partly local environmental conditions rather than global climatic trends.

Four spicule-bearing chaetetid sponges are described from Upper Triassic (Norian) reef carbonates of the WesternTaurids (Antalya-Region, SW Turkey): Atrochaetetes alakirensisCuif & Fischer, Blastochaetetes dolomiticusBizzarini & Braga, Ptychochaetetes sp. and ?Bauneia sp.. Spicules are preserved as calcitic pseudomorphs. They are either short and thick or long and slender, corresponding to typical styles; oxes are rarely present in Atrochaetetes alakirensis. The styles are mainly embedded in the secondary rigid skeleton, but their rounded ends appear to be attached to the primary wall. In Blastochaetetes dolomiticus and ?Bauneia sp. styles are also embedded in the primary wall. A comparison of these spicule-skeletons with those of other chaetetids, especially Paleozoic species, confirms the polyphyletic origin of the Taxon Chaetetida.