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Reijmer, C.H.; Oerlemans, J. (2002). Temporal and spatial variability of the surface energy balance in Dronning Maud Land, East Antarctica. J. Geophys. Res., 107.
Abstract: We present data of nine Automatic Weather Stations (AWS), which are located in Dronning Maud Land (DML), East Antarctica, since the austral summer of 1997. Potential temperature and wind speed are maximum at the sites with the steepest surface slope, i.e., at the edge of the Antarctic plateau. Specific humidity and accumulation decrease with elevation and distance from the coast. The annual average energy gain at the surface from the downward sensible heat flux varies between ?3 W m?2 and ?25 W m?2, with the highest values at the sites with the largest surface inclination and wind speeds. The net radiative flux is negative and largely balances this sensible heat flux and ranges from ??2 W m?2 to ??28 W m?2; maximum values can be linked to maxima in surface slope and wind speed, and suggest a strong connection between the heat budget and the katabatic flow in DML. The average latent heat flux is generally small and negative (??1 W m?2) indicating a slight net mass loss through sublimation.
Keywords: 1827 Hydrology: Glaciology; 1863 Hydrology: Snow and ice; 3307 Meteorology and Atmospheric Dynamics: Boundary layer processes; 3349 Meteorology and Atmospheric Dynamics: Polar meteorology; 9310 Information Related to Geographic Region: Antarctica
Programme: 960
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. (2012). An updated and quality controlled surface mass balance dataset for Antarctica
. The Cryosphere, 6(5), 3667–3702.
Abstract: We present an updated and quality controlled surface mass balance (SMB) database for the Antarctic ice sheet. We retrieved a total of 5284 SMB data documented with important meta-data, to which a filter was applied to discard data with limited spatial and temporal representativeness, too small measurement accuracy, or lack of quality control. A total of 3438 reliable data was obtained, which is about four times more than by applying the same data filtering process to previously available databases. New important data with high spatial resolution are now available over long traverses, and at low elevation in some areas. However, the quality control led to a considerable reduction in the spatial density of data in several regions, particularly over West Antarctica. Over interior plateaus, where the SMB is low, the spatial density of measurements remained high. This quality controlled dataset was compared to results from ERA-Interim reanalysis to assess model representativeness over Antarctica, and also to identify large areas where data gaps impede model validation. Except for very few areas (e.g. Adelie Land), the elevation range between 200 m and 1000 m a.s.l. is not correctly sampled in the field, and measurements do not allow a thorough validation of models in regions with complex topography, where the highest scattering of SMB values is reported. Clearly, increasing the spatial density of field measurements at low elevations, in the Antarctic Peninsula and in West Antarctica remains a scientific priority.
Programme: 411
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F. Pitout, A. Marchaudon, K. J. Trattner, J. Berchem, H. Laakso, C. P. Escoubet. (2020). Simultaneous Polar and Cluster Observations in the Northern and Southern Middle-Altitude Polar Cusps Around Equinox (Vol. 125).
Abstract: We present an event of simultaneous observations of the northern and southern middle-altitude polar cusps by the Polar spacecraft and Cluster fleet that occurred on 23 September 2004. We examine the possible asymmetries in the fields and plasma parameters, although the proximity of the equinox should limit these asymmetries. Ion sensors reveal two dispersions in both cusps, and data analysis leads to the conclusion that those dispersions are due to pulsed reconnection at a single X-line, which runs along the subsolar magnetopause. While the electromagnetic and particle energy fluxes injected in both cusp are globally very similar, we report significant differences in ion dispersions, width of the low-latitude boundary layer, and peak convection velocities. We ascribe these differences to the dipole tilt that introduces an asymmetry in the magnetosheath flow at the exterior cusps.
Keywords: dayside magnetosphere hemispheric asymmetry polar cusp
Programme: 312
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David C, Haefele A, Keckhut P, Marchand M, Jumelet J, Leblanc T, Cenac C, Laqui C, Porteneuve J, Haeffelin M, Courcoux Y, Snels M, Viterbini M, Quatrevalet M, . (2012). Evaluation of stratospheric ozone, temperature, and aerosol profiles from the LOANA lidar in Antarctica
. Polar Science, 6(34), 209–225.
Keywords: Polar ozone, Polar stratospheric clouds, Lidar, Stratosphere,
Programme: 209
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T. Shirai, M. Ishizawa, R. Zhuravlev, A. Ganshin, D. Belikov, M. Saito, T. Oda, V. Valsala, A. J. Gomez-Pelaez, R. Langenfelds, S. Maksyutov. (2017). (Vol. 69).
Keywords: carbon cycle carbon dioxide coupled model flux estimation inversion top-down approach tropical Asia
Programme: 416
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Andrea Spolaor, Beatrice Moroni, Bart?omiej Luks, Adam Nawrot, Marco Roman, Catherine Larose, ?ukasz Stachnik, Federica Bruschi, Krystyna Kozio?, Filip Pawlak, Clara Turetta, Elena Barbaro, Jean-Charles Gallet, David Cappelletti. (2021). Investigation on the Sources and Impact of Trace Elements in the Annual Snowpack and the Firn in the Hansbreen (Southwest Spitsbergen) (Vol. 8).
Abstract: We present a thorough evaluation of the water soluble fraction of the trace element composition (Ca, Sr, Mg, Na, K, Li, B, Rb, U, Ni, Co, As, Cs, Cd, Mo, Se, Eu, Ba, V, Ge, Ga, Cr, Cr, P, Ti, Mn, Zr, Ce, Zn, Fe, Gd, Y, Pb, Bi, Yb, Al, Nb, Er, Nd, Dy, Sm, Ho, Th, La, Lu, Tm, Pr, Tb, Fe, In, Tl) and their fluxes in the annual snowpack and the firn of the Hansbreen (a tidewater glacier terminating in the Hornsund fjord, southwest Spitsbergen). The trace element samples were obtained from a 3 m deep snow pit dug at the plateau of the glacier (450 m a.s.l.), and from a 2 m deep firn core collected from the bottom of the snow pit. The comparison of elemental fluxes and enrichment factors allowed us to constrain specific summer and wintertime deposition patterns of water soluble trace elements in the southern part of the Svalbard archipelago. Our results suggest that the chemical composition of the Hansbreen (and likely other glaciers where the summit is close to the equilibrium line) is mainly affected by summertime deposition of trace elements from local sources and some volatile elements, which may be transported into the Arctic when polar vortex is weak. The melting of the annual snowpack seems to have a minor influence on the overall chemical signature of the glacier ice.
Programme: 1192
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Chisham G, Freeman M P, Abel G A, Bristow W A, Marchaudon A, Ruohoniemi J M, Sofko G J, . (2009). Spatial distribution of average vorticity in the high-latitude ionosphere and its variation with interplanetary magnetic field direction and season
. J. Geophys. Res., 114(A9), A09301–.
Keywords: ionosphere, vorticity, field-aligned current, 2431 Ionosphere: Ionosphere/magnetosphere interactions, 2409 Ionosphere: Current systems, 2437 Ionosphere: Ionospheric dynamics, 2494 Ionosphere: Instruments and techniques, 2721 Magnetospheric Physics: Field-aligned currents and current systems,
Programme: 312;911
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. (2023). The subantarctic lithospheric mantle (Vol. 56).
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De Lauretis M., Patrizia Francia, Andrea Piancatelli, Massimo Vellante, Umberto Villante. (2009). Low and mid-frequency pulsations in the polar cap: polarization pattern and MLT dependence of the spectral power during the descending phase of the solar cycle. Annals of geophysics, 52(1), 27–34.
Keywords: ULF waves; Antarctica; Geomagnet; ic pulsations; Polarization pattern; upstream waves
Programme: 1130
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. (2020). Dome C coherence time statistics from DIMM data (Vol. 496).
Abstract: We present a reanalysis of several years of DIMM data at the site of Dome C, Antarctica, to provide measurements of the coherence time $\tau0$. Statistics and seasonal behaviour of $\tau0$ are given at two heights above the ground, 3m and 8m, for the wavelength $\lambda=500$nm. We found an annual median value of $2.9$ms at the height of 8m. A few measurements could also be obtained at the height of 20m and give a median value of 6ms during the period June--September. For the first time, we provide measurements of $\tau0$ in daytime during the summer, which appears to show the same time dependence as the seeing with a sharp maximum at 5pm local time. Exceptional values of $\tau0$ above 10ms are met at this particular moment. The continuous slow variations of turbulence conditions during the day offers a natural test bed for a solar adaptive optics system.
Keywords: Astrophysics – Instrumentation and Methods for Astrophysics
Programme: 1066
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