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Legrand M., Raynaud D., Barnola J.M. & Chappellaz J. (1994). Trends in global distribution of trace gases inferred from polar ice cores. (Vol. I).
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Weimerskirch H., Inchausti P., Guinet C. & Barbraud C. (2003). Trends in bird and seal populations as indicators of a system shift in the Southern Ocean. Antarct. Sci., 15, 249–256.
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Philippe Ricaud, Paolo Grigioni, Romain Roehrig, Pierre Durand, Dana E. Veron. (2020). Trends in Atmospheric Humidity and Temperature above Dome C, Antarctica Evaluated from Observations and Reanalyses (Vol. 11). Bachelor's thesis, , .
Abstract: The time evolution of humidity and temperature above Dome C (Antarctica) has been investigated by considering data from (1) meteorological radiosondes (2005–2017), (2) the microwave radiometer HAMSTRAD (2012–2017), (3) four modern meteorological reanalyses (1980–2017) and (4) the southern annular mode (SAM) index (1980–2017). From these observations (2005–2017), a significant moistening trend (0.08 ± 0.06 kg m−2 dec−1) is associated with a significant warming trend (1.08 ± 0.55 K dec−1) in summer. Conversely, a significant drying trend of −0.04 ± 0.03 kg m−2 dec−1 (−0.05 ± 0.03 kg m−2 dec−1) is associated with a significant cooling trend of −2.4 ± 1.2 K dec−1 (−5.1 ± 2.0 K dec−1) in autumn (winter), with no significant trends in the spring. We demonstrate that 1) the trends identified in the radiosondes (2005–2017) are also present in the reanalyses and 2) the multidecadal variability of integrated water vapor and near-surface temperature (1980–2017) is strongly influenced by variability in the SAM index for all seasons but spring. Our study suggests that the decadal trends observed in humidity and near-surface temperature at Dome C (2005–2017) reflect the multidecadal variability of the atmosphere, and are not indicative of long-term trends that may be related to global climate change.
Keywords: meteorological reanalyses microwave radiometer precipitable water radiosondes SAM index temperature trends
Programme: 910
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Philippe Ricaud, Paolo Grigioni, Romain Roehrig, Pierre Durand, Dana E. Veron. (2020). Trends in Atmospheric Humidity and Temperature above Dome C.
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Ropert-Coudert Y., Wilson R.P. (2005). Trends and perspectives in animal-attached recording tags. Frontiers in ecology and the environment, 3(8), 437–444.
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Benistant C. (1997). Transport plasmatique et cellulaire des acides gras chez les oiseaux developpant une thermogenese sans frisson. Doctoral thesis, , .
Abstract: Thèse Université
Programme: 131
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Gallée Hubert, Trouvilliez Alexandre, Agosta Cécile, Genthon Christophe, Favier Vincent, Naaim-Bouvet Florence, . (2013). Transport of Snow by the Wind: A Comparison Between Observations in Adélie Land, Antarctica, and Simulations Made with the Regional Climate Model MAR
. BOUNDARY-LAYER METEOROLOGY, 146(1), 133–147-.
Abstract: For the first time a simulation of blowing snow events was validated in detail using one-month long observations (January 2010) made in Adélie Land, Antarctica. A regional climate model featuring a coupled atmosphere / blowing snow / snowpack model is forced laterally by meteorological re-analyses. The vertical grid spacing ranged from 2 m to 20 m above the surface and the horizontal grid spacing was 5 km. The simulation was validated by comparing the occurrence of blowing snow events and other meteorological parameters at two automatic weather stations. The Nash test allowed us to compute efficiencies of the simulation. The regional climate model simulated the observed wind speed with a positive efficiency (0.69). Wind speeds higher than 12 m s-1 were underestimated. Positive efficiency of the simulated wind speed was a prerequisite for validating the blowing snow model. Temperatures were simulated with a slightly negative efficiency (--0.16) due to overestimation of the amplitude of the diurnal cycle during one week, probably because the cloud cover was underestimated at that location during the period concerned. Snowfall events were correctly simulated by our model, as confirmed by field reports. Because observations suggested that our instrument (an acoustic sounder) tends to overestimate the blowing snow flux, data were not sufficiently accurate to allow the complete validation of snow drift values. However, the simulation of blowing snow occurrence was in good agreement with the observations made during the first 20 days of January 2010, despite the fact that the blowing snow flux may be underestimated by the regional climate model during pure blowing snow events. We found that blowing snow occurs in Adélie Land only when the half-hourly wind speed value at 2 m a.g.l. is higher than 10 m s-1 . The validation for the last 10 days of January 2010 was less satisfactory because of complications introduced by surface melting and refreezing.
Keywords: Antarctica, Blowing snow, Regional climate model, Surface mass balance,
Programme: 1013
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Mahowald, N.M.; Rasch, P.J.; Eaton, B.E.; Whittlestone, S.; Prinn, R.G. (). Transport of 222radon to the remote troposphere using the Model of Atmospheric Transport and Chemistry and assimilated winds from ECMWF and the National Center for Environmental Prediction/NCAR. J. Geophys. Res., 102.
Abstract: The Model of Atmospheric Transport and Chemistry (MATCH) is used to simulate the transport of 222Rn using both European Centre for Medium-Range Weather Forecasts (ECMWF) winds and National Center for Environmental Prediction/National Center for Atmospheric Research (hereafter referred to as NCEP) reanalysis winds. These winds have the advantage of being based on observed winds but have the disadvantage that the subgrid-scale transport processes are not routinely archived. MATCH derives subgrid-scale mixing rates for the boundary layer using a nonlocal scheme and for moist convective mixing using one of two parameterizations (Tiedtke [1989] or Pan and Wu [1997]). This paper describes the ability of the model to recreate mixing rates of 222Rn using the forecast center winds. Radon 222 is a species with a continental crust source and a simple sink involving radioactive decay with an e-folding timescale of 5.5 days. This atmospheric constituent is therefore a good tracer for testing the vertical transport in the chemical transport model, as well as the horizontal transport from continental regions to remote oceanic regions. The various simulations of 222Rn are compared with observations as well as with each other, allowing an estimate of the uncertainty in transport due to uncertainties in the winds and subgrid-scale processes. The calculated vertical profiles over the western United States are somewhat similar to observed, and the upper tropospheric concentrations compare reasonably well in their spatial distribution with data collected during Tropospheric Ozone II (TROPOZ II), although the model values tend to be higher than observed values, especially in the upper troposphere. The model successfully simulates specific observed pollution events at Cape Grim. It has more difficulty at sites farther from continental source regions, although the model captures the seasonal structure of the pollution events at these sites (Macquarie Island, Amsterdam Island, Kerguelen Island, and Crozet Island). Inclusion of a moist convective mixing scheme in MATCH increases 222Rn concentrations in the upper troposphere by 50% compared to not having moist convective mixing, while surface concentrations do not appear to be very sensitive to moist convection. In addition, differences between the upper tropospheric concentrations of radon predicted using the ECMWF and NCEP winds can be 30% for large areas of the globe, due to either differences in the forecast center winds themselves or the moist convective mixing schemes used in conjunction with them. This has implications for model simulations of radiatively and chemically important trace species in the atmosphere.
Programme: 146
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Villemain, A. & Rosnet, E. (2011). Transmission process during turnover in Antarctica. 12-17 July, FEPSAC Madere, Portugal..
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Villemain, A. & Rosnet, E. (2011). Transmission process during turnover in Antarctica. .
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