RESEARCH
- Sea Ice - atmosphere - ocean coupling
- Freeze-up processes
- Marginal ice zone processes
- Upper ocean dynamics
- Polynya dynamics
- Remote sensing of snow and ice
- Instrumentation for sea ice environments
- Unmanned aircraft-based systems
ABOUT ME
I am currently a graduate student at University of Colorado Boulder working on my Ph.D. in Aerospace Engineering, with a concentration in Remote Sensing, Earth and Space Science. I work with Dr. Scott Palo in the Colorado Center for Astrodynamics Research.
I currently serve on the APECS Executive Committee and as Co-Chair of USAPECS.
I am funded under the NASA Earth and Space Science Fellowship.
CONTACT
alice.bradley@colorado.edu
Colorado Center for Astrodynamic Research
ECNT 320, 431 UCB
University of Colorado
Boulder, CO 80309-0431
PHOTOS
From field work and other cold places.
PROJECTS
All content is property of Alice Bradley
Ph.D. Candidate
Alice C. Bradley
Marginal Ice ZOne Processes Experiment (MIZOPEX)
Unmanned aircraft as a sensing platform for process-level studies of mixed ice environments.
Now in the analysis phase of the project, I am using observations from the Air Deployed MicroBuoys (ADMBs) of near-surface temperature gradients with depth. Comparison with reanalysis surface weather data shows the forcing mechanisms for the surface temperature gradients - high winds induce mixing. Proximity to melting floes is indicated by cold water right at the surface. Water far from the melting floes is often much warmer.
During the field campaign, I assisted with deployment of the ADMBs and with flight planning and launching the Self-Deployed Surface Sensors.
My involvement wIth MIZOPEX prior to the field campaign included assisting with system testing before the scheduled deployment and testing temperature sensors to verify that the deployable microbuoy system meets calibration and resolution requirements.
MIZOPEX project page: http://ccar.colorado.edu/mizopex/
Polynya Dynamics in Terra Nova Bay
More unmanned aircraft, this time in the high winds of Antarctic spring.
I am comparing conditions in and around the Polynya (wave height, ice thickness, etc) to local meteorological conditions. A series of flights over the Terra Nova Bay polynya (and the Ross Sea Polynya) over three weeks collected surface temperature measurements, laser altimetry data, and in situ meteorological measurements.
mizopex
Everything Else
Thesis topic:
Ice formation in the
Arctic Ocean
Observed processes in atmosphere-ocean coupling.
The Arctic seasonal ice zone undergoes dramatic changes throughout the year: in the summer, ice cover melts off, leaving the ocean surface exposed to the atmosphere. Warm surface air temperatures and incident solar radiation heat the water near the surface, and mixing induced by wind forcing stirs this into the rest of the mixed layer. At the end of the summer season, the mixed layer must then cool to the freezing point in order for ice to form at the surface.
The evolution of the temperature structure of the mixed layer prior to freeze-up has been poorly documented, though some observations exist. The processes leading up to freeze-up are of particular interest to Arctic operational users who are interested in the ice forecast for a particular area. Parameterizations of the mixed layer depth enable easier calculation of heat content, which is related to the time it takes to cool the surface layer. Further analysis of observational profiles of the fall mixed layer indicate that significant amounts of heat gets trapped under the mixed layer for periods ranging from days to weeks.
The Arctic ice cover has been shown to be overall thinning over the past decades through the continued loss of thick, multi-year ice. Thinner ice cover melts sooner, allowing more time for the ocean to warm throughout the summer. With ice growth initiating later in the season, the informal hypothesis within the field is that the end of season ice pack will be thinner.
The focus of my proposed thesis is on processes surrounding ice formation in the Arctic, first in the lead up to ice growth through the thermal evolution of the mixed layer in the fall and then considering the impacts on the seasonal ice pack from delayed ice growth. A field campaign studying an Antarctic coastal polynya in the closing phase (low wind, dominated by ice growth) provides a comparison for thin ice growth rates. The observational records considered in this project involve both in situ measurements and remote sensing products, supplemented by reanalysis estimates of atmospheric state. The focus is primarily in the Beaufort Sea due to the availability of data.