Contact information


Joel C. Plummer
Ph.D. Candidate
*
Center for the Remote Sensing of the Ice Sheets (CReSIS)
318 Nichols Hall
2335 Irving Hill Rd
Lawrence, KS 66045
*
Department of Geography
411 Lindley Hall
1475 Jayhawk Blvd
Lawrence, KS 66045
*
plummer at ku dot edu



Contents:


1. Velocity & Thickness Profile

2. Channel Data

3. 1995 Force Budget

4. 2000 & 2005  Velocity Transects

5. Bed Elevation Data






Jakobshavn Velocity & Thickness Profile




Data:
2006 Surface Elevation from ASTER DEM, courtesy of B. Csatho, SUNY BUffalo
2006 Bed Elevation from CReSIS Depthsounder Radar (May30a), CReSIS, University of Kansas
2000 OSU Surface Velocity, courtesy of Byrd Polar Research Center, The Ohio State University
2000 Joughin Surface Velocity, courtesy of I. Joughin, University of Washington

Plotted using R for Mac OS X.







Jakobshavn Channel


Velocity transects are named "A" through "T" starting with the western-most (left) transect and working east (right). Yellow stars denote location of successful radar soundings from 2006 flight shown above. Transects are spaced ~1800m on channel center and are oriented perpendicular to the flow based on flowlines from a 2001 LandSat image. Transect "A" was ~1-2km above the 2006 calving front.
  





All (1995,2000,2005) channel widths:


Plotted in R for Mac OS X.




1995 channel widths:



Plotted in R for Mac OS X.











1995 Jakobshavn Force Budget



1995 velocity transects:

The following plots compare 2000 OSU and Joughin Velocity measurements along the transects 'A' through 'T' shown above.  Flip through the plots using the arrows at the bottom.


Previous    slideshow Next
Plotted in R for Mac OS X.




1995 Force Budet Components:


Plotted in R for Mac OS X.








Jakobshavn 2000 & 2005 Velocities


2000 velocity transects:

The following plots compare 2000 OSU and Joughin Velocity measurements along the transects 'A' through 'T' shown above.  Flip through the plots using the arrows at the bottom.


Previous    slideshow Next
Plotted in R for Mac OS X.


2005 velocity transects:

The following plots compare 2005 OSU and Joughin Velocity measurements along the transects 'A' through 'T' shown above.  Flip through the plots using the arrows at the bottom.


Previous slideshow Next
Plotted in R for Mac OS X.
                                              


2000 & 2005 Joughin transects derived from 100m grids, courtesy of I. Joughin, University of Washington

2000 & 2005 OSU data transects derived from 100m grids kriged by J. Plummer from 400m point lattices (w/ gaps), courtesy of Byrd Polar Research Center, The Ohio State University






Jakobshavn Bed ELEVATION


Dataset currently unavailable. [9/9/10]


Date of last revision:
7/1/2010

Dataset Name:
Jakobshavn Bed Elevation

File Summary:
Comma delineated text file with header row.
X = latitude, decimal degrees N
Y = longitude, decimal degrees W
Z = Bed Elevation, meters

Data Description:
Using airborne ice/snow penetrating radar, ice thickness measurements were collected between 1997 and 2009 over the Jakobshavn Isbrae, Greenland.  The 2006 main channel channel HAS been included in this dataset.  LIDAR ice surface elevation measurements were also collected for each mission except the 2006 centerline flight.  For that line, an ice surface elevation profile was provided by ASTER satellite, courtesy of B. Csatho, University of Buffalo. At each sounding location, the ice thickness was subtracted from the ice surface elevation to provide a bed elevation.  These data were compiled and spatially interpolated (universal kriging) onto a raster surface with a horizontal resolution of 750m. A minimal amount of additional data were incorporated to complement the coverage of radar flight lines.  These additional data are surface elevation values over bare rock (ASTER satellite, courtesy of B. Csatho) on the ice sheet margin where the radar was unoperable.

Data:
    Grid Size = 147, 147  (pixels) 
    Pixel Size = 750, 750 (meters)

    Extent:
    Top       -2197249.83761
    Left       -447495.65284
    Right      -337245.65284
    Bottom    -2307499.83761

    Coordinate System:
    WGS_1984
    North Polar Sterographic
    Central Meridian = -39
    Standard Parallel = 71

    Max Elevation = 814.8 m
    Min Elevation = -1499.5 m

Notes:
This dataset represents an ongoing attept to describe the ice thickness at the Jakobshavn Isbrae, Greenland.  We are reprocessing coherent data collected over the Jakobshavn glacier with new algorithms to enhance echoes from ice-bed interface. This might result in a more accurate estimate of ice thickness. 

Contact:
Joel Plummer, PhD Candidate
Center for the Remote Sensing of the Ice Sheets
318 Nichols Hall
2335 Irving Hill Road
University of Kansas
Lawrence, KS 66045-7612
plummer@ku.edu




rev. 9/09/2010