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Dissolved gallium (Ga) concentrations are presented from the Beaufort Sea, representing the first reported values of Ga in the Arctic Ocean. Profiles of dissolved Ga in this region reflect Pacific and Atlantic Oceans source waters. Dissolved Ga concentrations of 4–6 pmol kg − 1 at depths < ~ 150 m are characteristic of dissolved Ga in the North Pacific, and at depths > ~ 350 m concentrations of 25–28 pmol kg − 1 are indicative of Atlantic waters. A smooth gradient of increasing dissolved Ga concentrations is observed through the thermocline, consistent with mixing of cool Pacific waters of low Ga concentration and relatively warm Atlantic waters of higher Ga concentration. Dissolved Ga is shown here to represent a complimentary tracer of Pacific inputs to the Western Arctic Ocean, as seasonal processes influencing temperature and Nitrate:Phosphate of Pacific Water entering the Arctic are not apparent in dissolved Ga profiles. Observed phosphate deficiency within nitrate deplete waters in the upper ~ 70 m is interpreted to result from nitrogen fixation in Pacific waters stored within the anticyclonic Beaufort Gyre. Conservative behavior of dissolved Ga within Pacific waters supports the interpretation here that nitrogen fixation rates calculated in this work are associated with Pacific source waters, as opposed to freshwater sources associated with the Mackenzie River or sea ice melt. Storage of phosphate deficient Pacific waters in the Beaufort Gyre followed by release and transport to the North Atlantic would result in pulses of phosphate deplete waters from the Arctic, impacting nitrogen fixation in the Atlantic Ocean. Sampling at one shelf station revealed local impacts on dissolved Ga concentrations, including high concentrations at shallow depths, interpreted to represent fresh waters inputs from the Mackenzie River or sea ice melt, while a restricted increase in Ga concentrations associated with the thermocline is suggested to result from increased scavenging rates within shelf environments due to increased particle abundance. Finally, first reports here of dissolved Ga in the Arctic allow comparison with profiles of dissolved Al. Distinct profiles of these two similar elements in the Arctic Ocean are interpreted to result from differential scavenging rates and vertical transport of dissolved Ga and Al within Atlantic sourced waters and deep basin waters. [ABSTRACT FROM AUTHOR]

The most exciting initiative for the recent polar studies was the International Polar Year (IPY) in 2007–2008. The IPY has witnessed a growing community of seismologists who have made considerable efforts to acquire high-quality data in polar regions. It also provided an excellent opportunity to make significant advances in seismic instrumentation of the polar regions to achieve scientific targets involving global issues. Taking these aspects into account, we organize and publish a special issue in Polar Science on the recent advance in polar seismology and cryoseismology as fruitful achievements of the IPY. [ABSTRACT FROM AUTHOR]

Following indications of recent warming trends in the Nordic Seas, we have studied the hydrography of these marginal seas from the summer of 2007 until the fall of 2008, using observations gathered by instrumented seals and Argo floats. The combined dataset shows that the upper ocean was indeed both warmer and saltier over much of the Nordic Seas in 2007–2008 compared to the average ocean state for the period 1956–2006 (based on the World Ocean Atlas 2009). There are also indications that the surface Polar Waters of the East Greenland Current were colder and fresher than the climatology, though the quality of the climatology is questionable for this region given the low number of historical observations. Dynamic height calculations suggest that the observed hydrographic changes were associated with enhanced northward upper-ocean thermal wind transport in the east and possibly also enhanced southward transport in the west. [ABSTRACT FROM AUTHOR]

Rural community participation in scientific knowledge production processes has become a central component of research and development policy and practice internationally. However, relatively little is known about the factors that influence the development of successful research partnerships in the applied natural sciences, as well as their associated outcomes. This paper presents an in-depth case study of a successful community-researcher natural resource science partnership in the Canadian Arctic. The results suggest both context and process-related factors were important to the research partnership, including funding and performance assessment processes, leadership and capacity at the community level, the proposal development and research design strategies, and the timing and perceived transparency in results dissemination. Researchers and local stakeholders also strongly valued the informal interactions that are often not part of the research process in the natural sciences. This “idle time” spent in the community facilitated the development of local networks and friendships and played an important role in building the human and social capital of all stakeholders. The outcomes of the partnership strategies used by those involved were numerous and went beyond the more tangible financial benefits, including outcomes such as legitimizing the knowledge systems of both parties and aiding in their integration and mutual understanding. [ABSTRACT FROM AUTHOR]

Highlights: [•] Novel approach to quantitatively and systematically evaluate the usability of climate change research for informing decision-making. [•] Application to Canadian International Polar Year. [•] Usable science widely promoted but not a major consideration in the design of Canadian International Polar Year projects focusing on climate change. [•] Key attributes of pertinence, quality, and timeliness absent in many projects. [•] Significant differences in usability between social and biophysical sciences. [ABSTRACT FROM AUTHOR]

The northernmost limb of the Atlantic Meridional Overturning Circulation (AMOC), so relevant for understanding decadal climate variability, enters the Nordic Seas as the Norwegian Atlantic Current and continues on to recirculate in the Arctic Ocean. The strength of the Eastern Branch of the Norwegian Atlantic Current has been systematically monitored for over 15 years at the Svinøy section off southern Norway, whereas the strength of the Western Branch has not. We therefore used autonomous gliders to monitor and quantify the strength of this broader branch at the Svinøy section, located 500km downstream from the Iceland–Scotland Ridge, and at the Station Mike section 300km further downstream. The gliders' diving depth is 1000m, spanning the warm Atlantic Water. The current encompasses more than warm Atlantic Water; we find that the transport peaks in two distinct temperature ranges, one around 7.5–8°C (Atlantic Water, carrying 7Sv (1×106 m3/s)) and another around −0.5°C (Norwegian Sea Deep Water, carrying 12Sv). Contrary to earlier expectations, our results indicate that the Western Branch carries as much water of Atlantic origin (temperature>7.5°C) as the Eastern Branch. It should therefore be included in future monitoring plans for this region. [ABSTRACT FROM AUTHOR]

Abstract: The spatial distribution, biogeochemical cycle and external sources of dissolved cobalt (DCo) were investigated in the southeastern Atlantic and the Southern Ocean between 33°58′S and 57°33′S along the Greenwich Meridian during the austral summer 2008 in the framework of the International Polar Year. DCo concentrations were measured by flow-injection analysis and chemiluminescence detection in filtered (0.2μm), acidified and UV-digested samples at 12 deep stations in order to resolve the several biogeochemical provinces of the Antarctic Circumpolar Current and to assess the vertical and frontal structures in the Atlantic sector of the Southern Ocean. We measured DCo ranging from 5.73±1.15 pM to 72.9±4.51 pM. The distribution of DCo was nutrient-like in surface waters of the subtropical domain with low concentrations in the euphotic layer due to biological uptake. The biological utilization of dissolved cobalt was proportional to that of phosphate in the subtropical domain with a DCo:HPO4 2− depletion ratio of ~44μMM−1. In deeper waters the distribution indicated remineralization of DCo and inputs from the margins of South Africa with lateral advection of enriched intermediate and deep waters to the southeastern Atlantic Ocean. In contrast the vertical distribution of DCo changed southward, from a nutrient-like distribution in the subtropical domain to scavenged-type behavior in the domain of the Antarctic Circumpolar Current and conservative distribution in the Weddell Gyre. There the cycle of DCo featured low biological removal by Antarctic diatoms with input to surface waters by snow, removal in oxygenated surface waters, and dissolution and stabilization in the low-oxygenated Upper Circumpolar Deep Waters. DCo distributions and physical hydro-dynamics features also suggest inputs from the Drake Passage and the southwestern Atlantic to the 0° meridian along the eastward flow of the Antarctic Circumpolar Current. Bottom enrichment of DCo in the Antarctic Bottom Waters was also evident, together with increasing water-mass pathway and aging, possibly due to sediment resuspension and/or mixing with North Atlantic Deep waters in the Cape Basin. Overall atmospheric input of soluble Co by dry aerosols to the surface waters was low but higher in the ACC domain than in the northern part of the section. At the highest latitudes, it is possible that snowfall could be a source of DCo to surface waters. Tentative budgets for DCo in the mixed layer of the subtropical and the ACC domains have been constructed for each biogeochemical region encountered during the cruise. The estimated DCo uptake flux was found to be the dominant cobalt flux along the section. This flux decreases southward, which is consistent with the observations that DCo shows a southward transition from nutrient-like towards conservative distribution in the mixed layer. [Copyright &y& Elsevier]

Abstract: Polycyclic aromatic hydrocarbons (PAH) were measured in air samples at a remote air monitoring site established in the Yukon Territory, Canada as part of a global project (International Polar Year; IPY) to study the potential for atmospheric long-range transport of anthropogenic pollutants to the Arctic. Gas- and particle-phase PAH were collected in polyurethane foam plugs and on glass fibre filters respectively from August 2007 to October 2009. PAH concentrations were found to be highest in the winter months and lowest in summer. The gas/particle partitioning coefficients of 3–5 ringed PAH were computed and seasonal averages were compared. In the summer time, lower molecular mass PAH exhibited relatively higher partitioning into the particle-phase. This particle-phase partitioning led to the shallowest slopes being recorded during summer for the log–log correlation plots between the PAH partition coefficients and their sub-cooled vapour pressures. Air mass back trajectories suggest that local impacts may be more important during the summer time which is marked by increased camping activities at camping sites in the proximity of the sampling station. In conclusion, both summer and wintertime variations in PAH concentrations and gas/particle partitioning are considered to be source- and phototransformation-dependent rather than dependent on temperature-driven shifts in equilibrium partitioning. [ABSTRACT FROM AUTHOR]

Abstract: Monitoring the evolution of polar glaciers, ice caps and ice streams is of utmost importance because they constitute a good indicator of global climate change and contribute significantly to ongoing sea level rise. Accurate topographic surveys are particularly relevant as they reflect the geometric evolution of ice masses. Unfortunately, the precision and/or spatial coverage of current satellite missions (radar altimetry, ICESat) or field surveys are generally insufficient. Improving our knowledge of the topography of Polar Regions is the goal of the SPIRIT (SPOT 5 stereoscopic survey of Polar Ice: Reference Images and Topographies) international polar year (IPY) project. SPIRIT will allow (1) the acquisition of a large archive of SPOT 5 stereoscopic images covering most polar ice masses and, (2) the delivery of digital terrain models (DTM) to the scientific community. Here, we present the architecture of this project and the coverage achieved over northern and southern polar areas during the first year of IPY (July 2007 to April 2008). We also provide the first accuracy assessments of the SPIRIT DTMs. Over Jakobshavn Isbrae (West Greenland), SPIRIT elevations are within ±6 m of ICESat elevations for 90% of the data. Some comparisons with ICESat profiles over Devon ice cap (Canada), St Elias Mountains (Alaska) and west Svalbard confirm the good overall quality of the SPIRIT DTMs although large errors are observed in the flat accumulation area of Devon ice cap. We then demonstrate the potential of SPIRIT DTMs for mapping glacier elevation changes. The comparison of summer-2007 SPIRIT DTMs with October-2003 ICESat profiles shows that the thinning of Jakobshavn Isbrae (by 30–40 m in 4 years) is restricted to the fast glacier trunk. The thinning of the coastal part of the ice stream (by over 100 m) and the retreat of its calving front (by up to 10 km) are clearly depicted by comparing the SPIRIT DTM to an ASTER April-2003 DTM. [Copyright &y& Elsevier]

Abstract: During the International Polar Year (IPY), one area of great interest is co-coordinated, multi-instrument probing of the ionosphere at high latitudes. This region is important not only for the applications that rely upon our understanding of it, but also because it contains the footprints of processes that have their origin in the interplanetary space. Many different techniques are now available for probing the ionosphere, from radar measurements to the analysis of very low frequency (VLF) wave paths. Combining these methods provides the ability to study the ionosphere from high in the F-region to the bottom of the D-layer. Thus, coupling processes from the magnetosphere and to the neutral atmosphere can be considered. An additional dimension is through comparisons of the response of the two polar ionospheres to similar (or the same) geomagnetic activity. With more instruments available at the South Pole inter-hemispheric, studies have become easier to accomplish such that a fuller picture of the global response to Sun–Earth coupling can be painted. This paper presents a review of the current state of knowledge in ionospheric probing. It cannot provide a comprehensive guide of the work to date due to the scale of the topic. Rather it is intended to give an overview of the techniques and recent results from some of the instruments and facilities that are a part of the IPY cluster 63—Heliosphere Impact on Geospace. In this way it is hoped that the reader will gain a flavor of the recent research performed in this area and the potential for continuing collaboration and capabilities during the IPY (2007–2009). [Copyright &y& Elsevier]

Abstract: The Antarctic ice sheet is arguably the most critical in terms of future sea-level rise, primarily because it contains ∼70% of the world''s fresh water. While there exists evidence of accelerated ice-sheet ablation during the past decade, the possibility that the ice sheets contributed little to 20th century sea-level rise could result in Antarctica becoming the largest contributor to sea-level rise during the 21st century. Here we review the findings of studies published following the 2007 Intergovernmental Panel for Climate Change (IPCC) study, focusing on the role of Antarctica in present-day (1992–2006) sea-level rise. We show that the choice of glacial isostatic adjustment (GIA) model significantly affects GRACE-estimated Antarctic mass loss, adding 0.25–0.45mm/yr to the estimate of sea-level rise. The current estimate of Antarctica''s contribution to sea-level rise has a wide range: from −0.12 to +0.52mm/yr. The discrepancy between observed sea-level trend of 1.8mm/yr and those estimated from various geophysical sources (2.10±0.99mm/yr) is 0.30mm/yr. The role of Antarctica in sea-level rise might be better constrained by lengthening satellite observations, using long-term GPS data to discriminate subglacial vertical motion from ice mass balance, and detecting the sea-level signal due to elastic loading from the melting ice-sheets. [Copyright &y& Elsevier]

Abstract: Monitoring the response of land ice to climate change requires accurate and repeatable topographic surveys. The SPOT5-HRS (High Resolution Stereoscopic) instrument covers up to 120 km by 600 km in a single pass and has the potential to accurately map the poorly known topography of most glaciers and ice caps. The acquisition of a large HRS archive over ice-covered regions is planned by the French Space Agency (CNES) and Spotimage, France during the 2007–2008 International Polar Year (IPY). Here, we report on the accuracy and value of HRS digital elevation model (DEM) over ice and snow surfaces. A DEM is generated by combining tools available from CNES with the PCI OrthoengineSE software, using HRS images acquired in May 2004 over South-East Alaska (USA) and northern British Columbia (Canada). The DEM is evaluated through comparison with shuttle radar topographic mission (SRTM) DEM and ICESAT data, on and around the glaciers. A horizontal shift of 50 m is found between the HRS and SRTM DEMs and is attributed to errors in the SRTM DEM. Over ice-free areas, HRS elevations are 7 m higher than those of SRTM, with a standard deviation of ±25 m for the difference between the two DEMs. The 7-m difference is partly attributed to the differential penetration of the electromagnetic waves (visible for HRS; microwave for SRTM) in snow and vegetation. We also report on the application of sequential DEMs (SRTM DEM in February 2000 and HRS DEM in May 2004) for the monitoring of glacier elevation changes. We map the topographic changes induced by a surge of one tributary of Ferris Glacier. Maximum surface lowering of 42 (±10) m and rising of 77 (±10) m are observed in the 4 years time interval. Thinning rates up to 10 (±2.5) m/yr are observed at low altitudes and confirm the ongoing wastage of glaciers in South-East Alaska. [Copyright &y& Elsevier]

Abstract: An overview is given of research activities in South Africa related to the International Heliophysical Year in 2007. The emphasis is on Space Physics (Geospace and Heliospace). A short historical perspective is given, followed by a description of the main research efforts. [Copyright &y& Elsevier]