Stephanie Higgins

Stephanie Higgins CV

Postdoctoral Researcher

Departments

Education

  • PhD Geological Sciences: University of Colorado Boulder, 2014
  • BS Geology: Bates College, 2008

Contact Information

(Office) 303 492-2841

Specialty

Coastal subsidence and relative sea level rise; remote sensing of coastal zones; InSAR; natural hazards; radar and remote sensing.

Bio

Click here for a summary of my research topics.

Awards

  • NSF Graduate Research Fellowship, National Science Foundation, 2009
  • Louis Jordan Jr. Award for Outstanding Thesis in Geology, Bates College, 2008
  • Angelo Tagliocozzo Memorial Geologic Scholarship, American Institute of Professional Geologists (AIPG), 2008
Photo Gallery

Research

Research Statement

Primary Research Topics

Land subsidence measured with D-InSAR

Land subsidence in river deltas can heighten storm surges, salinate groundwater, intensify river flooding, destabilize infrastructure, and accelerate shoreline retreat. Using satellite-based D-InSAR (Differential Interferometric Synthetic Aperture Radar), we measured land motion along the coast of the Yellow River Delta in China. We found that groundwater pumping at fish farms has caused subsidence rates as high as 250 mm/y, which exceeds local and global average sea level rise by nearly two orders of magnitude. These results suggest a major hazard for Asian megadeltas, where fish farming dominates land-use and groundwater pumping is common to regulate salinity in ponds. To learn more about this problem, see the original publication in Geophysical Research Letters [Higgins et al., 2013], or read these associated features on the websites of Nature or the UN-sponsored Future Earth program. Sprechen Sie Deutsch? Check out this recent interview with German Public Radio!

Subsidence in the Yellow River Delta, China, measured with D-InSAR. From Higgins et al. [2013]

Urban subsidence measured with SBAS-InSAR

Groundwater extraction, hydrocarbon extraction, tectonics, isostatic adjustment and natural compaction of sediments can all cause cities to sink, but without high-resolution measurements it can be impossible to tell which is having the greatest impact in any given city. Interferometric Synthetic Aperture Radar (InSAR) is a satellite-based technique that can produce maps of ground deformation with mm-scale vertical accuracy. In Higgins et al. [2014], we used a technique called Small Baseline Subset (SBAS) InSAR to search for controls on subsidence in major cities such as Dhaka, Bangladesh, where dense populations exert rapidly-changing influences on the surface and subsurface.

Land subsidence in Dhaka, Bangladesh, measured with SBAS-InSAR. From Higgins et al [2014].

Visible and infrared remote sensing

In addition to its many other applications, visible and infrared remote sensing can be used to map inundation, identify new reservoirs, track coastline changes, and measure suspended sediment concentrations in rivers. From time to time I team up with the Flood Observatory (formerly Dartmouth Flood Observatory/DFO) at CU-Boulder to look at these applications. In 2012, I joined the DFO on a publication examining the potential for global mapping of storm surges using a number of sensors [Brakenridge et al., 2012]. In 2016, we are collaborating on an analysis of the flood history of Myanmar, using DFO products to examine the flood events during the period when the country was largely closed to international press. With IPython Notebooks from Google Earth Engine developers, I also mapped and classified irrigation inundation at 30-m resolution in Bangladesh using the MCD12 (MODIS) Landcover classification as a training dataset for LANDSAT-7 observations.

Inundation (red) of the distal portions of the Mississippi River Delta due to the Hurricane Katrina storm surge, mapped by SPOT, RADARSAT, and LANDSAT, August 30 to September 4, 2005. From Brakenridge et al. [2012].

Delta sustainability and risk assessment modeling

I am part of the Belmont Forum’s DELTAS project, an international collaboration of government, university, and NGO researchers focused on vulnerability and sustainability of coastal river deltas. In this project I am working to co-develop an open-access, science-based, integrative modeling framework called the Delta Risk Assessment and Decision Support (RADS) Tool, which can provide a quantitative basis for investigating and comparing scenarios and trade-offs for decision making. Towards this end, I work with global precipitation and climate data, census data, Digital Elevation Models, Open Street Map extracts, and several other datasets that are combined in a GIS framework to automatically produce model inputs and provide model parameter estimation. As a first test for RADS, we are investigating how proposed dams and water transfers in India might soon impact sediment transport to the Ganges-Brahmaputra Delta in Bangladesh.

Hurricane Rainfall, Gulf Coast, USA

Mitigating the impacts of tropical cyclones requires accurate forecasts of precipitation within the storm. A deeper understanding of tropical cyclone rainfall is also desirable because of the large role tropical cyclones can play in regional water budgets. In the Gulf Coast region, for example, between five and ten percent of total annual precipitation can come from tropical cyclones. Improving hurricane models requires samples of actual rainfall collected from inside of hurricanes, but rain gauges often cannot withstand the conditions inside of a landfalling storm. With a member of my dissertation committee, Dr. Katja Friedrich, I developed a quality-control algorithm to improve measurements of raindrop size distributions in severe weather. We applied this algorithm to data collected inside of Hurricanes Ike and Rita (2008), which made landfall along the Texas coast in 2008 [Friedrich, Higgins et al., 2013].

Doppler on Wheels (DOW) radar imagery of Hurricane Ike, Galveston, TX, 2008.

Active Research

Research Programs

Publications

FeaturedPublications

Stephanie HigginsIrina Overeem, Rogers, K. G., Kalina, E. A. 2018: River linking in India: Downstream impacts on water discharge and suspended sediment transport to deltas. Elementa: Science of the Anthropocene, 6: article 20. DOI: 10.1525/elementa.269

Friedrich, K., Stephanie Higgins, Masters, F. J., Lopez, C. R. 2013: Articulating and stationary PARSIVEL disdrometer measurements in conditions with strong winds and heavy rainfall. Journal of Atmospheric and Oceanic Technology, 30: 2063-2080. DOI: 10.1175/JTECH-D-12-00254.1

Rogers, K. G., Irina OvereemStephanie Higgins, Gilligan, J., Jaia Syvitski 2013: Farming practices and anthropogenic delta dynamics. Redbook Proceedings of HP1, IAHS-IAPSO-IASPEI Assembly, Gothenburg, Sweden, July 2013, IAHS publ. 358, 133-142.

Theses & Dissertations

Academics

Outreach

Outreach Statement

Outreach and Volunteer Work

Communications and research mentor for undergraduate students through the UNAVCO RESESS program, 2014-present.

Software Carpentry Bootcamp organizer for 45 graduate students, Jan 2015. Software Carpentry Bootcamps teach Unix, Python and GitHub basics and coding best-practices.

"Portal to the Public" Science Ambassador for K5 students - CU Discovery Science Center and Boulder Public Library, Oct 2015.

NSF Experienced Resource Person for the Graduate Research Fellowship Program (GRFP), 2009-present. I volunteer to help students in US western states prepare fellowship applications in all disciplines. Feel free to contact me with questions.

Graduate student representative to the INSTAAR directorate (governing body of our institute), 2012-2013.

Reviewer for Remote Sensing, Hydrogeology Journal, Science of the Total Environment, Geophysical Research Letters, and Nature.

Research mentor for high school student in the Intel Science Fair program - Monro was awarded a Regional Special Prize, way to go Monro!

Volunteer K12 teacher and tutor at Altona Middle School, Centaurus High School, and Northglenn High School, 2010-2011.

Misc

Etc.

List of Collaborators:

Mike Stecker, Lamont-Doherty Earth Observatory, Columbia University

Akiko Tanaka, National Institute of Advanced Industrial Science and Technology (AISTJapan)

James P. M. Syvitski, Community Surface Dynamics Modeling System (CSDMS), University of Colorado Boulder

G. Robert Brakenridge, Dartmouth Flood Observatory, University of Colorado Boulder 

Waqas Qazi, Institute of Space Technology, Pakistan

Irina Overeem, University of Colorado Boulder

Chris Jenkins, University of Colorado Boulder

Fei Xing, Water Institute of the Gulf

Humayun Akhter, University of Dhaka

Evan Kalina, National Oceanic and Atmospheric Administration (NOAA)

Efi Foufoula-Georgiou, Departments of Civil and Environmental Engineering and Earth System Science, University of California Irvine

Zachary Tessler, CUNY Advanced Science Research Center

Charles Vörösmarty, CUNY Advanced Science Research Center

Kimberly Rogers, University of Colorado Boulder