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• 1. [Article] Women in Glaciology, an Historical Perspective

  Women's history in glaciology extends as far back in time as the discipline itself, although their contributions to the scientific discourse have for all of that history been constrained by the sociopolitical ...

  Citation × Citation Citation Abstract Copy Title: Women in Glaciology, an Historical Perspective Author: Hulbe, Christina L., Wang, Weili, Ommanney, Simon Year: 2010 Women's history in glaciology extends as far back in time as the discipline itself, although their contributions to the scientific discourse have for all of that history been constrained by the sociopolitical contexts of the times. The first Journal of Glaciology paper authored by a woman appeared in 1948, within a year of the founding of the Journal, but it was not until the 1980s that women produced more than a few percent of Journal and Annals of Glaciology papers. Here international perspectives on women's participation in the sciences are presented in order to establish an economic and sociopolitical context for stories of women 'pioneers' in glaciology and a frame in which to discuss women's persistent under-representation relative to men. We find that the experiences of individual glaciologists mirror women's experiences in higher education and the sciences as a whole. The existence of both positive and negative trends in women's participation in the sciences suggests caution in the interpretation of recent positive trends for women's participation in glaciology. Title: Women in Glaciology, an Historical Perspective Author: Hulbe, Christina L., Wang, Weili, Ommanney, Simon Year: 2010 Women's history in glaciology extends as far back in time as the discipline itself, although their contributions to the scientific discourse have for all of that history been constrained by the sociopolitical contexts of the times. The first Journal of Glaciology paper authored by a woman appeared in 1948, within a year of the founding of the Journal, but it was not until the 1980s that women produced more than a few percent of Journal and Annals of Glaciology papers. Here international perspectives on women's participation in the sciences are presented in order to establish an economic and sociopolitical context for stories of women 'pioneers' in glaciology and a frame in which to discuss women's persistent under-representation relative to men. We find that the experiences of individual glaciologists mirror women's experiences in higher education and the sciences as a whole. The existence of both positive and negative trends in women's participation in the sciences suggests caution in the interpretation of recent positive trends for women's participation in glaciology. Close

• 2. [Article] Post-Stagnation Behavior in the Upstream Regions of Ice Stream C, West Antarctica

  The region where two active tributaries feed into the now stagnant Ice Stream C (ISC), West Antarctica, is thickening. In this region, we observe a correlation between faster ice flow (the tributaries) ...

  Citation × Citation Citation Abstract Copy Title: Post-Stagnation Behavior in the Upstream Regions of Ice Stream C, West Antarctica Author: Price, Stephen F., Bindschadler, R. A., Hulbe, Christina L., Joughin, Ian R. Year: 2001 The region where two active tributaries feed into the now stagnant Ice Stream C (ISC), West Antarctica, is thickening. In this region, we observe a correlation between faster ice flow (the tributaries) and elevated topography. We conclude that stagnation of ISC resulted in compression and thickening along the tributaries, eventually forming a "bulge" on the ice-sheet surface. Modern hydraulic potential gradients would divert basal meltwater from ISC to Ice Stream B (ISB). These gradients are primarily controlled by the bulge topography, and so likely formed subsequent to trunk stagnation. As such, we argue against "water piracy" as being the cause for ISC's stagnation. Kinematic-wave theory suggests that thickness perturbations propagate downstream over time, but that kinematic-wave speed decreases near the stagnant trunk. This and modest diffusion rates combine to trap most of the tributary-fed ice in the bulge region. Using interferometric synthetic aperture radar velocity measurements, we observe that half of the ice within ISC's southern tributary flows into ISB. That flow pattern and other observations of non-steady flow in the region likely result from stagnation-induced thickening along upper ISC combined with a longer period of thinning on upper ISB. If current trends in thickness change continue, more ice from upper ISC will be diverted to ISB. Title: Post-Stagnation Behavior in the Upstream Regions of Ice Stream C, West Antarctica Author: Price, Stephen F., Bindschadler, R. A., Hulbe, Christina L., Joughin, Ian R. Year: 2001 The region where two active tributaries feed into the now stagnant Ice Stream C (ISC), West Antarctica, is thickening. In this region, we observe a correlation between faster ice flow (the tributaries) and elevated topography. We conclude that stagnation of ISC resulted in compression and thickening along the tributaries, eventually forming a "bulge" on the ice-sheet surface. Modern hydraulic potential gradients would divert basal meltwater from ISC to Ice Stream B (ISB). These gradients are primarily controlled by the bulge topography, and so likely formed subsequent to trunk stagnation. As such, we argue against "water piracy" as being the cause for ISC's stagnation. Kinematic-wave theory suggests that thickness perturbations propagate downstream over time, but that kinematic-wave speed decreases near the stagnant trunk. This and modest diffusion rates combine to trap most of the tributary-fed ice in the bulge region. Using interferometric synthetic aperture radar velocity measurements, we observe that half of the ice within ISC's southern tributary flows into ISB. That flow pattern and other observations of non-steady flow in the region likely result from stagnation-induced thickening along upper ISC combined with a longer period of thinning on upper ISB. If current trends in thickness change continue, more ice from upper ISC will be diverted to ISB. Close

• 3. [Article] Variability in the Mass Flux of the Ross Sea Ice Streams, Antarctica, over the last Millennium

  We synthesize previously published remote-sensing observations, radar data and model output to obtain a ~1000 year ice flow history for the Siple Coast ice-stream system in West Antarctica to investigate ...

  Citation × Citation Citation Abstract Copy Title: Variability in the Mass Flux of the Ross Sea Ice Streams, Antarctica, over the last Millennium Author: Catania, Ginny, Hulbe, Christina L., Conway, Howard, Scambos, Ted A., Raymond, C. F. Year: 2012 We synthesize previously published remote-sensing observations, radar data and model output to obtain a ~1000 year ice flow history for the Siple Coast ice-stream system in West Antarctica to investigate the timing and magnitude of changes in mass flux. The synthesized history shows significant short-term variability in ice-stream shear margin and grounding line position due to internal variability of the coupled system. The chronology highlights the interplay between adjacent ice streams, which implies that the behavior of any individual ice stream should not be examined in isolation. Furthermore, individual events cannot be fully interpreted without an understanding of the broad-scale, long-term variability in the ice sheet. In the context of this millennium-scale history, we interpret the relatively recent stagnation of Kamb Ice Stream (KIS) as just one stage in the thermodynamic cycle of an ice stream in this region. The changes in mass balance that result from the KIS stagnation may thus be viewed as century-scale ?noise? relative to the longer-term trend. Understanding and characterizing this noise is a necessary step before accurate model-based predictions of ice-sheet mass balance for the next century can be made. Title: Variability in the Mass Flux of the Ross Sea Ice Streams, Antarctica, over the last Millennium Author: Catania, Ginny, Hulbe, Christina L., Conway, Howard, Scambos, Ted A., Raymond, C. F. Year: 2012 We synthesize previously published remote-sensing observations, radar data and model output to obtain a ~1000 year ice flow history for the Siple Coast ice-stream system in West Antarctica to investigate the timing and magnitude of changes in mass flux. The synthesized history shows significant short-term variability in ice-stream shear margin and grounding line position due to internal variability of the coupled system. The chronology highlights the interplay between adjacent ice streams, which implies that the behavior of any individual ice stream should not be examined in isolation. Furthermore, individual events cannot be fully interpreted without an understanding of the broad-scale, long-term variability in the ice sheet. In the context of this millennium-scale history, we interpret the relatively recent stagnation of Kamb Ice Stream (KIS) as just one stage in the thermodynamic cycle of an ice stream in this region. The changes in mass balance that result from the KIS stagnation may thus be viewed as century-scale ?noise? relative to the longer-term trend. Understanding and characterizing this noise is a necessary step before accurate model-based predictions of ice-sheet mass balance for the next century can be made. Close