11/3/2022 0 Comments Buoyant flexture![]() ![]() ![]() However, neither approach can reproduce the range of behaviour typical of a large marine-terminating glacier such as Helheim5. Here calving front position occurs where ice thickness reaches some height threshold above flotation and calving rate becomes a function of ice flux to the terminus3,7. Subsequently, empirical relationships were linked to physical properties of the glacier using the height-above-buoyancy criterion. Glacier models originally parameterized iceberg calving using an independent variable such as water depth (for example, ref. We suggest that this buoyancy-driven mechanism for calving may be common elsewhere in Greenland and could be a rst-order control on the ice sheets future contribution to sea-level rise. Our digital elevation models are derived from stereo terrestrial photographytakenoverthesummersof2010and2011.Wend that during these two summers dynamic mass loss at Helheim Glacier was dominated by calving events exceeding 1 km3 that were the result of buoyant exure and the propagation of basal crevasses. Here we present a record of daily digital elevation models from the calving margin of Greenlands Helheim Glacier at a high spatial resolution. ![]() However, present physical models remain a coarse approximation of real calving mechanisms because models are poorly constrained by sparse glacier geometry observations5. The largest contributions from the main outlet glaciers of the Greenland ice sheet to sea-level rise over the next two centuries have been projected to be dynamic in origin, that is, driven by glacier ow and calving4. ![]() Iceberg calving accounts for a signicant proportion of annual mass loss from marine-terminating glaciers1,2 and may haveīeen a factor in the rapid demise of ancient ice sheets3. James*, Tavi Murray, Nick Selmes, Kilian Scharrer and Martin OLeary A second exemplary embodiment of the method represents an incremental approach to achieving the target orientation.Timothy D. A first exemplary embodiment of the method represents a target approach to achieving the target orientation. Particular embodiments of the method include comparing an actual orientation of the second assembly with a target orientation, actuating the control device to perform a control device actuation cycle if the actual orientation is not acceptable, determining an updated actual orientation of the second assembly, comparing the updated actual orientation with the target orientation, and repeating the control device actuation cycle if the updated target orientation is not acceptable. Abstract: -a subsea pump (30) arranged in fluid connection with the well interior (38, 39) providing a closed system suitable for pressure and flow regulation and establishing a temporary fluid flow between the subsea pump and the well interior, -a fluid source (31) supplying fluid to the subsea pump, wherein the subsea pump has a mode of operation for regulation of the flow and/or pressure between the pump and the well interior to operate equipment arranged in the well, -a safety control system for controlling shut down of a valve arrangement in a subsea position, which safety control system is also arranged in a subsea position and comprises a control unit (60) and an actuation unit (70) for local control and operation of the valve arrangement, -the valve arrangement is operated by the control unit into a valve configuration providing a barrier system between a reservoir in fluid communication with the well interior and the surroundings, -a plurality of sensors (100, 51, 52) arranged for measuring fluid parameters trĪbstract: In an apparatus of the type comprising a first assembly, a second assembly, an orientable rotatable connection between the first assembly and the second assembly, and a control device associated with the orientable rotatable connection, a method for controlling the actuation of the control device. ![]()
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