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A. Adriani - One of the best experts on this subject based on the ideXlab platform.
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South-polar features on Venus similar to those near the North Pole
Nature, 2007Co-Authors: G. Piccioni, P. Drossart, A. Sanchez-lavega, R. Hueso, F. W. Taylor, C. F. Wilson, D. Grassi, L. Zasova, M. Moriconi, A. AdrianiAbstract:ESA's Venus Express probe has been in orbit since April 2006. Eight research papers in this issue present new results from the mission, covering the atmosphere, polar features, interactions with the solar wind and the controversial matter of venusian lightning. Håkan Svedham et al . open the section with a review of the similarities and (mostly) differences between Venus and its 'twin', the Earth. Andrew Ingersoll considers the latest results, and also how the project teams plan to make the most of the probe's remaining six years of life. Venus has a bright 'diPole' double-eye feature at the centre of a vast vortex that rotates around the North Pole, and is surrounded by a cold 'collar'. Observations of Venus' south polar region are reported, where clouds with morphology much like those around the North Pole are seen, but rotating somewhat faster. Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright ‘diPole’ feature surrounded by a cold ‘collar’ at its North Pole^ 1 , 2 , 3 , 4 . The polar diPole is a ‘double-eye’ feature at the centre of a vast vortex that rotates around the Pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a diPole feature existed at the south Pole. Here we report observations of Venus’ south-polar region, where we have seen clouds with morphology much like those around the North Pole, but rotating somewhat faster than the Northern diPole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south Pole are compatible with a sulphuric acid composition.
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south polar features on venus similar to those near the North Pole
Nature, 2007Co-Authors: G. Piccioni, P. Drossart, R. Hueso, F. W. Taylor, C. F. Wilson, D. Grassi, L. Zasova, M. Moriconi, A Sanchezlavega, A. AdrianiAbstract:Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright 'diPole' feature surrounded by a cold 'collar' at its North Pole. The polar diPole is a 'double-eye' feature at the centre of a vast vortex that rotates around the Pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a diPole feature existed at the south Pole. Here we report observations of Venus' south-polar region, where we have seen clouds with morphology much like those around the North Pole, but rotating somewhat faster than the Northern diPole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south Pole are compatible with a sulphuric acid composition.
G. Piccioni - One of the best experts on this subject based on the ideXlab platform.
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South-polar features on Venus similar to those near the North Pole
Nature, 2007Co-Authors: G. Piccioni, P. Drossart, A. Sanchez-lavega, R. Hueso, F. W. Taylor, C. F. Wilson, D. Grassi, L. Zasova, M. Moriconi, A. AdrianiAbstract:ESA's Venus Express probe has been in orbit since April 2006. Eight research papers in this issue present new results from the mission, covering the atmosphere, polar features, interactions with the solar wind and the controversial matter of venusian lightning. Håkan Svedham et al . open the section with a review of the similarities and (mostly) differences between Venus and its 'twin', the Earth. Andrew Ingersoll considers the latest results, and also how the project teams plan to make the most of the probe's remaining six years of life. Venus has a bright 'diPole' double-eye feature at the centre of a vast vortex that rotates around the North Pole, and is surrounded by a cold 'collar'. Observations of Venus' south polar region are reported, where clouds with morphology much like those around the North Pole are seen, but rotating somewhat faster. Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright ‘diPole’ feature surrounded by a cold ‘collar’ at its North Pole^ 1 , 2 , 3 , 4 . The polar diPole is a ‘double-eye’ feature at the centre of a vast vortex that rotates around the Pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a diPole feature existed at the south Pole. Here we report observations of Venus’ south-polar region, where we have seen clouds with morphology much like those around the North Pole, but rotating somewhat faster than the Northern diPole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south Pole are compatible with a sulphuric acid composition.
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south polar features on venus similar to those near the North Pole
Nature, 2007Co-Authors: G. Piccioni, P. Drossart, R. Hueso, F. W. Taylor, C. F. Wilson, D. Grassi, L. Zasova, M. Moriconi, A Sanchezlavega, A. AdrianiAbstract:Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright 'diPole' feature surrounded by a cold 'collar' at its North Pole. The polar diPole is a 'double-eye' feature at the centre of a vast vortex that rotates around the Pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a diPole feature existed at the south Pole. Here we report observations of Venus' south-polar region, where we have seen clouds with morphology much like those around the North Pole, but rotating somewhat faster than the Northern diPole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south Pole are compatible with a sulphuric acid composition.
John E. Walsh - One of the best experts on this subject based on the ideXlab platform.
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Statistical analysis of atmospheric forcing of North Pole ice draft variations
Journal of Geophysical Research: Oceans, 1999Co-Authors: Timothy L. Shy, John E. WalshAbstract:A series of correlation experiments and regression models are used to explore the atmospheric forcing of observed interannual variability in North Pole ice drafts as measured by U.S. Navy submarine sonar from 1982 to 1992. Mean ice drafts as well as ice draft distributions are used in the analysis. Nearby drifting buoys are used to approximate a full 2-year motion history of the North Pole ice parcels prior to submarine underpass. Drawing from theoretical work and empirical observation, predictors of North Pole ice draft variation are selected which embody accumulated ice exposure to subfreezing air temperature, ice divergence, and patterns of ice motion. The timescales of the predictors are based on systematic evaluations of the lag dependence of the predictor-predictand relationships. Linear correlation of each predictor with the observed ice draft distribution shows accumulated ice exposure to subfreezing air temperature is weakly correlated with reductions in shallow (0 to 2.5-m) drafts. Ice divergence a week prior to draft measurement correlates most closely with the redistribution of ice drafts shallower than 3.5 m. Ice divergence and ice deflection from its wind-forced motion during the 6 months prior to observation correlate with deeper ice drafts (deeper than 6.8 and 4.6 m, respectively). Together, these two parameters explain more than 80% of the variance of the observed mean ice draft. The accumulated ice exposure to subfreezing air temperatures colder than the 1980–1992 mean in the 2 years prior to ice arrival at the North Pole adds little to an explanation of the interannual variance of the mean ice draft. The results imply that (1) a realistic formulation of sea ice dynamics is a first-order priority for model simulations of ice draft and (2) North Pole ice thickness is not a simple function of Arctic air temperature.
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North Pole ice thickness and association with ice motion history 1977-1992
Geophysical Research Letters, 1996Co-Authors: Timothy L. Shy, John E. WalshAbstract:Ice drafts measured by U.S. Navy submarine sonar near the North Pole from 1977 to 1992 were used together with Arctic Ocean drifting buoy data from 1979 to 1992 to investigate North Pole ice thickness changes during this 15-year period. A primary objective was to determine dynamical forcing mechanisms and associated time scales relevant to ice thickness variation. North Pole ice thickness showed much interannual variability, and no systematic decrease of ice thickness was observed. Changes in ice thickness were closely associated with long-term directional deviation of ice motion from geostrophic wind-forcing, and with ice convergence and divergence at the North Pole during the 1–2 weeks prior to submarine measurement. The geographic origin of ice within the Arctic Ocean was not associated with its eventual thickness at the North Pole.
D. Grassi - One of the best experts on this subject based on the ideXlab platform.
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South-polar features on Venus similar to those near the North Pole
Nature, 2007Co-Authors: G. Piccioni, P. Drossart, A. Sanchez-lavega, R. Hueso, F. W. Taylor, C. F. Wilson, D. Grassi, L. Zasova, M. Moriconi, A. AdrianiAbstract:ESA's Venus Express probe has been in orbit since April 2006. Eight research papers in this issue present new results from the mission, covering the atmosphere, polar features, interactions with the solar wind and the controversial matter of venusian lightning. Håkan Svedham et al . open the section with a review of the similarities and (mostly) differences between Venus and its 'twin', the Earth. Andrew Ingersoll considers the latest results, and also how the project teams plan to make the most of the probe's remaining six years of life. Venus has a bright 'diPole' double-eye feature at the centre of a vast vortex that rotates around the North Pole, and is surrounded by a cold 'collar'. Observations of Venus' south polar region are reported, where clouds with morphology much like those around the North Pole are seen, but rotating somewhat faster. Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright ‘diPole’ feature surrounded by a cold ‘collar’ at its North Pole^ 1 , 2 , 3 , 4 . The polar diPole is a ‘double-eye’ feature at the centre of a vast vortex that rotates around the Pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a diPole feature existed at the south Pole. Here we report observations of Venus’ south-polar region, where we have seen clouds with morphology much like those around the North Pole, but rotating somewhat faster than the Northern diPole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south Pole are compatible with a sulphuric acid composition.
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south polar features on venus similar to those near the North Pole
Nature, 2007Co-Authors: G. Piccioni, P. Drossart, R. Hueso, F. W. Taylor, C. F. Wilson, D. Grassi, L. Zasova, M. Moriconi, A Sanchezlavega, A. AdrianiAbstract:Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright 'diPole' feature surrounded by a cold 'collar' at its North Pole. The polar diPole is a 'double-eye' feature at the centre of a vast vortex that rotates around the Pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a diPole feature existed at the south Pole. Here we report observations of Venus' south-polar region, where we have seen clouds with morphology much like those around the North Pole, but rotating somewhat faster than the Northern diPole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south Pole are compatible with a sulphuric acid composition.
L. Zasova - One of the best experts on this subject based on the ideXlab platform.
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South-polar features on Venus similar to those near the North Pole
Nature, 2007Co-Authors: G. Piccioni, P. Drossart, A. Sanchez-lavega, R. Hueso, F. W. Taylor, C. F. Wilson, D. Grassi, L. Zasova, M. Moriconi, A. AdrianiAbstract:ESA's Venus Express probe has been in orbit since April 2006. Eight research papers in this issue present new results from the mission, covering the atmosphere, polar features, interactions with the solar wind and the controversial matter of venusian lightning. Håkan Svedham et al . open the section with a review of the similarities and (mostly) differences between Venus and its 'twin', the Earth. Andrew Ingersoll considers the latest results, and also how the project teams plan to make the most of the probe's remaining six years of life. Venus has a bright 'diPole' double-eye feature at the centre of a vast vortex that rotates around the North Pole, and is surrounded by a cold 'collar'. Observations of Venus' south polar region are reported, where clouds with morphology much like those around the North Pole are seen, but rotating somewhat faster. Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright ‘diPole’ feature surrounded by a cold ‘collar’ at its North Pole^ 1 , 2 , 3 , 4 . The polar diPole is a ‘double-eye’ feature at the centre of a vast vortex that rotates around the Pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a diPole feature existed at the south Pole. Here we report observations of Venus’ south-polar region, where we have seen clouds with morphology much like those around the North Pole, but rotating somewhat faster than the Northern diPole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south Pole are compatible with a sulphuric acid composition.
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south polar features on venus similar to those near the North Pole
Nature, 2007Co-Authors: G. Piccioni, P. Drossart, R. Hueso, F. W. Taylor, C. F. Wilson, D. Grassi, L. Zasova, M. Moriconi, A Sanchezlavega, A. AdrianiAbstract:Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright 'diPole' feature surrounded by a cold 'collar' at its North Pole. The polar diPole is a 'double-eye' feature at the centre of a vast vortex that rotates around the Pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a diPole feature existed at the south Pole. Here we report observations of Venus' south-polar region, where we have seen clouds with morphology much like those around the North Pole, but rotating somewhat faster than the Northern diPole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south Pole are compatible with a sulphuric acid composition.
