A last glacial ice sheet on the Pacific Russian coast and catastrophic change arising from coupled ice–volcanic interaction

Controversy exists over the extent of glaciation in Eastern Asia at the Last Glacial Maximum: complete ice sheet cover vs. restricted mountain icefields (an area discrepancy equivalent to 3.7 Greenland Ice Sheets). Current arguments favour the latter. However, significant last glacial ice-rafted debris (IRD) exists in NW Pacific ocean cores, which must have been sourced from a major ice sheet somewhere bordering the North Pacific. The origin of this IRD is addressed through a combination of marine core analysis, iceberg trajectory modelling and remote sensing of glacial geomorphology. We find compelling evidence for two stages of glaciation centred on the Kamchatka area of maritime southeast Russia during the last glacial, with ice extent intermediate in size between previous maximum and minimum reconstructions. Furthermore, a significant increase in iceberg flux precedes, and accompanies, a substantial marine core ash deposit at around 40ka BP. We speculate that rapid decay of the first stage of the ice sheet may have triggered substantial volcanic activity

Glacial thermohaline circulation states of the northern Atlantic: The compatibility of modelling and observations

We present 3He data froma repeat section across Drake Passage, fromthree sections off the South American continent in the Pacific, at 28?S, 35?S, and 43?S, and fromthree sections in the Atlantic, eastward of the Malvinas, close to 35?W, and near the Greenwich Meridian. In Drake Passage, a distinct high-3He signal is observed that is centered just above the boundary of the Lower and the Upper Circumpolar Deep Water (LCDW, UCDW), and is concentrated towards the northern continental slope. 3He concentrations in the Antarctic Circumpolar Current (ACC) upstream of Drake Passage (World Ocean Circulation Experiment section P19 at 88?W) are markedly lower than those found in Drake Passage, and a regional source of primordial helium in the path of the ACC that might cause the high-3He feature can be ruled out. We explain the feature by addition of high-3He waters present at the 43?S Pacific section. This supports a previous, similar interpretation of a low-salinity anomaly in Drake Passage (Naveira Garabato et al., Deep- Sea Research I 49 (2002) 681), that is strongly related to the high-3He feature. Employing multiparameter water mass analysis (including 3He as a parameter), we find that deep waters as met at the 43?S Pacific section, flowing south along the South American continental slope, contribute substantially to the ACC waters in Drake Passage (fractions exceed 50% locally). Lesser, but laterally more extended contributions are found east of the Malvinas, and still smaller ones are present at 35?W and at the Greenwich Meridian. Using velocity measurements from one of the two Drake Passage sections, we estimate the volume transport of these waters to be 7.071.2 Sv, but the average transport may be somewhat lower as the other realization had a less pronounced signal. The enhanced 3He signature in Drake Passage is essentially confined north of the Polar Front. Further downstreamthe signature crosses this front, to the extent that at 35?W the contributions south and north of it are of similar magnitude. At the same time, the 3He levels north of the front are reduced due to a substantial admixture of low-3He North Atlantic Deep Water, such that 3He becomes highest south of the front. The flow of Southeast Pacific deep slope waters entering the ACC constitutes the predominant exit pathway of the primordial helium released in the deep Pacific, and represents a considerable fraction of the deep water return flow fromthe Pacific into the ACC. Therefore and also because the density range of the added deep slope waters is intermediate between those of UCDW and LCDW, they must be considered a distinct water mass. r 2003 Elsevier Ltd. All rights reserved

Anne McLaren and the Human Embryo Research Debates in Britain, 1982–1990: Sociological Biography in the Analysis of Public Debate

I describe the role of the scientist Dr Anne McLaren in the public and parliamentary debates on human fertilisation and embryology (HF&E) in Britain between 1982 and the resulting Act in 1990. A focus on McLaren’s contributions to these debates elucidates how the case in favour of embryo research was constructed. Drawing especially on the use of the contested term ‘pre-embryo’ by the pro-human embryo research lobby to describe the subject of experimentation, and the development of pre-implantation genetic diagnosis (PGD) over the same time span as the debates, I show how a pro-research case was built around the idea that biology could be used towards broadly shared clinical goals. I tie this evolution of a case to McLaren’s expertise, and show how McLaren combined an authoritative scientific understanding with the idea of moral purpose and social good, necessitating a language that could reflect both. I go on to draw on McLaren’s biography, showing how she cultivated a ‘style of practice’ that relied on the non-literal translation of biological information to arrive at public consensus. I engage with several areas of literature, beginning with the literature on the HF&E debates and analyses of the use of the term ‘pre-embryo’ in science and technology studies, and feminist cultural studies. I add a more detailed description of the specific biological arguments made by the pro-research lobby and show how these reflected a shifting position for the scientist in public debate. I also contribute to material-semiotic methodologies used in feminist cultural studies by scholars such as Donna Haraway, Evelyn Fox-Keller, and Susan Squier, showing how close readings of key documents can be used to extrapolate from an individual’s life to better understand the causality of a public debate. My combined archival research and interviews with McLaren’s former collaborators leads me to foreground a particular tension around the legacy of the biological model used in the debates. I show how the scientists I interviewed repeatedly distanced themselves from the relativistic biological case they helped invent in the 1980s, describing their role instead as a literalist transmission of biological facts. An analysis of the work that McLaren did, I argue, serves as a reminder of the iterative process that scientists performed in order to arrive at a clinical translation. I use the metaphor of ‘superimposition’ to explicate this process, a term used by McLaren to describe her own approach to policy-making, as well as in the writing of C. H. Waddington, who was a formative inspiration to her as a scientist. The metaphor helps to describe McLaren’s method of layering social, legal, clinical, emotional and scientific arguments in order to build consensus based on overlapping concerns, and allows me to develop McLaren’s role as a case study in broadening the conventional use of ‘translation’ in the post-millennial climate of biomedicine. I conclude that a multi-faceted understanding of the process of translation offers a productive and inclusive model for policy discussions, and one which continues to prescribe a role for scientists in the process of developing legislation in biomedicine today.Wellcome Trus

Theology, science and the topos of the Logos: a stable, dynamic topology of Creation

This thesis argues that an integrated, dynamically stable theo-science may be explored by considering scientific and theological perspectives regarding stability itself, combining them in one overarching framework by embedding a scientific conception of stability within a broader theological conception thereof. Our very capacity to perceive ‘reality’ in a functionally consistent manner is dependent upon the physical cosmos presenting a particular, dynamic stability, allowing for the sustainable emergence of life in the first place. Stability is hierarchically qualified, with higher-order functional systems such as those pertaining to life being an emergent result of particular modes of interaction between lower-level degrees of stability, ultimately right down to fundamental particles or fields. Theologically, any stability inherent to ‘reality’ must furthermore be considered to derive from the fact that such reality is, at its profoundest, a manifestation of God’s revealing, Creative Activity through the Logos. The thesis considers, qualitatively, the scientific and theological ‘place’ and relevance of stability from a holistic perspective regarding our anthropological development. Scientifically this is viewed in layered, evolutionary terms. Theologically, the Incarnation is considered of central relevance to our anthropological journey, transfiguring the process of its development so as to draw human nature into its intended eschatological stability ‘at the right hand of the Father’. Since stability can be considered scientifically in topological terms, the framework is developed by means of a ‘theological topology’ centred, as the etymology suggests, on the idea of a sacramentally stable, pervasive topos indicative of God’s ‘motioning’, Creative Activity through the Logos. Such Activity becomes sense-objectified in the Incarnation, considered figuratively-speaking as a ‘phase transition’, the net effect of which is argued as a ‘drawing in’ (cf. John 12:32), reordering and enhancing all meaningful, creaturely contribution to the ‘content’ of Creation – content actively generated according to our iconic, creative capacity for conceiving (of) the Logos

Inversions of observations near the Azores Front

CTD data from Discovery Cruise 138 of late June, 1983 in the Madeira Abyssal Plain show a strong, but isolated, Mediterranean Water (MW) signal around 35N, 25W. This water mass gives rise to an anticyclonic eddy at its southward tip and, through double diffusive processes, to modification of the density field a few hundred meters below. Current estimates have been calculated from the cruise data using the Bernoulli inverse technique. Extensions of this inverse method, which take into account the depth dependence of dynamically informative density and potential vorticity functions, are developed to investigate the flow field and the consistency of the inversions. The Bernoulli inversions all show a strong eastward current in the upper 500 m around 34–35N. In the south of our study area the upper level flow is predominantly southward, consistent with current meter records from the NEADS 1 site at 33N, 22W. It is speculated that during the summer of 1983 there was a southward excursion of the Azores Front into this area, as has been recorded in the past

Spatially Resolved Velocity Mapping of the Melt Plume During High-Pressure Gas Atomization of Liquid Metals

We present details of an image analysis algorithm designed specifically to determine the velocity of material in the melt plume during high-pressure, close-coupled gas atomization. Following high-speed filming (16,000 fps) pairs of images are used to identify and track dominant features within the plume. Due to the complexity of the atomization plume, relatively few features are tracked between any given pair of images, but by averaging over the many thousands of frames obtained during high-speed filming a spatially resolved map of the average velocity of material in the plume can be built up. Velocities in the plume are typically very low compared to that of the supersonic gas, being around 30 m s−1 on the margins of the plume where the melt interacts strongly with the gas and dropping to < 10 m s−1 in the center of the melt plume. Consequently, the efficiency of the atomizer in transferring kinetic energy from the gas to the melt is correspondingly very low, with this being estimated as being no more than 0.1 pct

Introduction: The Laboratory of Nature - Science in the Mountains

"Today I made the ascent of the highest mountain in this region, which for good reasons is called Ventosum, guided only by the desire to see the extraordinary altitude of the place” (Petrarque [1336] 1880, 6-7). Petrarch's ascent of the Mont Ventoux in 1336, or rather his account of it, established the mountain as a distinctive place for experiencing and understanding nature and self. Since then, the mountain has been sought out in increasing numbers by those pursuing spiritual elevation, bodily exertion, and/or scientific investigation. To this day, a pilgrimage church, several hotels, and an observatory are characteristically perched atop Mont Ventoux. And it is famous among cyclists as a legendarily difficult étape of the Tour de Franc

Modelling abrupt glacial North Atlantic freshening: Rates of change and their implications for Heinrich events

The abrupt delivery of large amounts of freshwater to the North Atlantic in the form of water or icebergs has been thought to lead to significant climate change, including abrupt slowing of the Atlantic Ocean meridional overturning circulation. In this paper we examine intermediate complexity coupled modelling evidence to estimate the rates of change, and recovery, in oceanic climate that would be expected for such events occurring during glacial times from likely sources around the North Atlantic and Arctic periphery. We show that rates of climate change are slower for events with a European or Arctic origin. Palaeoceanographic data are presented to consider, through the model results, the origin and likely strength of major ice-rafting, or Heinrich, events during the last glacial period. We suggest that Heinrich events H1-H3 are likely to have had a significant contribution from an Arctic source as well as Hudson Strait, leading to the observed climate change. In the case of H1 and H2, we hypothesise that this secondary input is from a Laurentide Arctic source, but the dominant iceberg release for H3 is hypothesised to derive from the northern Fennoscandian Ice Sheet, rather than Hudson Strait. Earlier Heinrich events are suggested to be predominantly Hudson Strait in origin, with H6 having the lowest climate impact, and hence iceberg flux, but H4 having a climate signal of geographically variable length. We hypothesise that this is linked to a combination of climate-affecting events occurring around the globe at this time, and not just of Laurentide origin. (C) 2010 Elsevier B.V. All rights reserved

Modelling twentieth century global ocean circulation and iceberg flux at 48°N: Implications for west Greenland iceberg discharge

We have used a coupled ocean-iceberg model to study the variation in global ocean circulation and North Atlantic iceberg flux from 1900 to 2008. The latter component of the study focused particularly on Greenland icebergs feeding into the Labrador Current and past Newfoundland. The model was forced with daily heat, freshwater and wind fluxes from the Twentieth Century Reanalysis. The reanalysis heat fluxes were shown to be offset from the, shorter, NCEP reanalysis and a grid-point correction was applied to this component of the forcing. The model produces a generally realistic ocean circulation, although with an enhanced Atlantic Meridional Overturning largely due to the forcing. The modelled iceberg flux at 48°N is well correlated with the long-term observed flux when using a modelled iceberg discharge that varies in a similar fashion to the highly variable observed flux at 48°N. From this model we infer changes in the spatial and temporal variability of iceberg calving from western Greenland. During the first third of the twentieth century the majority of modelled icebergs reaching 48°N derive from southern Greenland, while only after 1930 is the traditional perspective of a majority of such icebergs originating from Baffin Bay consistent with model results. Decadal-scale changes in the dominant regional sources are found, with oscillations between western Greenland and northern Baffin Bay. The latter origin was modelled to be most important in the last third of the twentieth century, although west Greenland sources have increased in importance in recent years. The model correctly reproduces the pronounced late spring peak in flux at 48°N for southern Greenland icebergs, but has an approximately six month offset for icebergs from Baffin Bay, most likely due to resolution issues leading to model icebergs not being delayed in shallow coastal waters, whereas in reality they may be grounded for some time or trapped in coastal sea-ice. © 2015 The Authors

Reconstructing El Niño Southern Oscillation using data from ships’ logbooks, 1815–1854. Part II: Comparisons with existing ENSO reconstructions and implications for reconstructing ENSO diversity

© 2017 The Author(s) A systematic comparison of El Niño Southern Oscillation reconstructions during the early to mid-nineteenth century is presented using a range of proxy and documentary sources. Reconstructions of the boreal winter Southern Oscillation Index (SOI) using data from ships’ logbooks presented in a companion paper are evaluated and compared to previous ENSO reconstructions. Comparisons between ENSO reconstructions and the instrumental SOI during a period of overlap (1876–1977) are made. These same proxy and documentary reconstructions are then compared to the logbook-based reconstructions, over 1815–1854. The logbook-based reconstructions compare best with a recent multi-proxy reconstruction that used signals taken from different teleconnection regions, and they have an improved agreement with multi-proxy records compared to a previous attempt to reconstruct the SOI from ships’ logbook data. The logbook-based and the multi-proxy reconstructions are found to capture El Niño events better than La Niña events, and East Pacific El Niño events better than Central Pacific El Niño events, thus suggesting a degree of bias in the historical reconstructions. These findings have important implications for future ENSO reconstructions, with a need for an increased understanding of the effects of different ENSO flavours for future reconstructions