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A working group on Greenland Ice Sheet-Ocean Interactions (GRISO), composed of representatives from the multiple disciplines involved, was established in January 2011 to develop strategies to address dynamic response of Greenland's glaciers to climate forcing. Critical aspects of Greenland's coupled ice sheet-ocean system are identified, and a research agenda is outlined that will yield fundamental insights into how the ice sheet and ocean interact, their role in Earth's climate system, their regional and global effects, and probable trajectories of future changes. Key elements of the research agenda are focused process studies, sustained observational efforts at key sites, and inclusion of the relevant dynamics in Earth system models. Interdisciplinary and multiagency efforts, as well as international cooperation, are crucial to making progress on this novel and complex problem. This will prove as a significant step toward fulfilling the goal of credibly projecting sea level rise over the coming decades and century.

Glaciers and ice caps (GICs) are important contributors to present-day global mean sea level rise (1-4). Most previous global mass balance estimates for GICs rely on extrapolation of sparse mass balance measurements (1,2,4) representing only a small fraction of the GIC area, leaving their overall contribution to sea level rise unclear. Here we show that GICs, excluding the Greenland and Antarctic peripheral GICs, lost mass at a rate of 148 ± 30 Gt [yr.sup.-1] from January 2003 to December 2010, contributing 0.41 ± 0.08 mm [yr.sup.-1] to sea level rise. Our results are based on a global, simultaneous inversion of monthly GRACE-derived satellite gravity fields, from which we calculate the mass change over all ice-covered regions greater in area than 100 [km.sup.2]. The GIC rate for 2003-2010 is about 30 per cent smaller than the previous mass balance estimate that most closely matches our study period (2). The high mountains of Asia, in particular, show a mass loss of only 4 ± 20 Gt [yr.sup.-1] for 2003-2010, compared with 47-55 Gt [yr.sup.-1] in previously published estimates (2,5). For completeness, we also estimate that the Greenland and Antarctic ice sheets, including their peripheral GICs, contributed 1.06 ± 0.19 mm [yr.sup.-1] to sea level rise over the same time period. The total contribution to sea level rise from all ice-covered regions is thus 1.48 ± 0.26 mm [yr.sup.-1], which agrees well with independent estimates of sea level rise originating from land ice loss and other terrestrial sources (6)., Interpolation of sparse mass balance measurements on selected glaciers is usually used to estimate global GIC mass balance (1,2,4). Models are also used (3,7), but these depend on the quality [...]

The science of glaciology focuses on the mechanics and dynamics of glaciers with the aim of analyzing and solving problems in sea-level change, climate, geomorphology and oceanography. Scientists are using new remote sensing techniques which enable them to make special glacier observations that could not be accessed or were difficult to attain through traditional ground-based methods. The SAR interferometry is one of the new remote sensing techniques which have allowed scientists to obtain spatially dense and highly precise distributions of velocity vectors in glaciers in Alaska and in Greenland, Antarctica.

The article discusses a study which shows clock drift, timestamp precision, and subsecond reporting resolution as major hindrances to precise timekeeping of digital cameras and describes camera models' subsecond capability. It presents a methodology for calibrating cameras to have absolute timing. It mentions glaciological case studies that illustrate the relation of the methods to georeferencing of aerial photogrammetric surveys in which camera positions are time-interpolated from Global Positioning System (GPS) tracklogs and to coupling videos showing glacier calving to synchronous seismic waveforms.

The article explores the potential of a study of the built environment of the circumpolar Arctic to improve public understanding of the Arctic and its relation to the rest of the world. It looks at the influence of landscape on culture, noting that as the built environment expands in size and develops in complexity, culture starts to shape landscape. It proposes some efforts to convey to the public the modern human aspects of the Arctic, including photography of the built environment of the circumpolar Arctic.