1km Greenland data set

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One kilo-meter resolution data set for Greenland

There is a one kilo-meter resolution data set for Greenland available for download by clicking here.

The data set is in NetCDF format and includes data for bedrock topography, ice thickness, air temperature, precipitation, basal heat flux, and the meta-data in the table below. The data is on a 1501 by 2801 grid with lower left hand corner at (-800 000, -3 400 000) and upper right hand corner (700 000, -600 000).

Meta-data for the 1km resolution Greenland data set
GLOBAL ATTRIBUTES  
Title   Greenland 1 km Data Set
Creator   Glen D. Granzow
Institution   University of Montana
Date   1 November 2010 *
Comments   The data in this file was interpolated onto a 1km grid using natural neighbor interpolation which is based on Delauney triangulation. This was accomplished using the function natgridd (see http://www.ncarg.ucar.edu//ngmath/natgrid/nnhome.html) from the National Center for Atmospheric Research (NCAR). Natgrid is part of the NCAR Command Language (NCL) package which can be downloaded via http://www.ncl.ucar.edu/Download/
mapping  
ellipsoid   WGS84
grid_mapping_name   polar_stereographic
latitude_of_projection_origin   90
standard_parallel   71
straight_vertical_longitude_from_pole   -39
false_easting   0
false_northing   0
x  
long_name   Cartesian x-coordinate
standard_name   projection_x_coordinate
units   meters
y  
long_name   Cartesian y-coordinate
standard_name   projection_y_coordinate
units   meters
topg  
long_name   Bedrock Topography
standard_name   bedrock_altitude
units   meters
grid_mapping   mapping
source   [1] http://nsidc.org/data/nsidc-0092.html, [2] http://www.gebco.net/data_and_products/gridded_bathymetry_data/, [3] https://www.cresis.ku.edu/data/Greenland
reference   [1a] Bamber, J.L., R.L. Layberry, S.P. Gogenini. 2001. A new ice thickness and bed data set for the Greenland ice sheet 1: Measurement, data reduction, and errors. Journal of Geophysical Research 106 (D24): 33773-33780. [1b] Bamber, J.L., R.L. Layberry, S.P. Gogenini. 2001. A new ice thickness and bed data set for the Greenland ice sheet 2: Relationship between dynamics and basal topography. Journal of Geophysical Research 106 (D24): 33781-33788.
comments   The bedrock topography field incorporates (corrected) 5 km gridded data from the National Snow and Ice Data Center (NSIDC), bathymetric data and surface elevation data for Ellesmere Island from the General Bathymetric Chart of the Oceans (GEBCO), gridded data for the Jakobshavn and Pettermann Glacier regions from the Center for Remote Sensing of Ice Sheets (CReSIS), and flightline data for the Kangerdlugsuaq and Helheim Glacier regions also from CReSIS. Because of the large number of data points, interpolation onto the output grid (using natgridd's nonlinear natural neighbor algorithm) was performed in blocks to reduce the computing time required. The available flightline data was for ice thickness only; To calculate bed elevations from these thicknesses, the thicknesses were subtracted from surface elevations obtained using a bicubic spline of 5km gridded surface data from NSIDC.
thk  
long_name   Ice Thickness
standard_name   land_ice_thickness
units   meters
grid_mapping   mapping
source   [1] http://nsidc.org/data/nsidc-0092.html, [2] https://www.cresis.ku.edu/data/Greenland
reference   [1a] Bamber, J.L., R.L. Layberry, S.P. Gogenini. 2001. A new ice thickness and bed data set for the Greenland ice sheet 1: Measurement, data reduction, and errors. Journal of Geophysical Research 106 (D24): 33773-33780. [1b] Bamber, J.L., R.L. Layberry, S.P. Gogenini. 2001. A new ice thickness and bed data set for the Greenland ice sheet 2: Relationship between dynamics and basal topography. Journal of Geophysical Research 106 (D24): 33781-33788.
comments   The ice thickness field incorporates (corrected) 5 km gridded data from the National Snow and Ice Data Center (NSIDC), gridded data for the Jakobshavn and Pettermann Glacier regions from the Center for Remote Sensing of Ice Sheets (CReSIS), and flightline data for the Kangerdlugsuaq and Helheim Glacier regions also from CReSIS. Additional data points with zero thickness were introduced to smooth the ice margin but artifacts of the 5 km grid remain in some locations. Because of the large number of data points, interpolation onto the output grid (using natgridd's nonlinear natural neighbor algorithm) was performed in blocks to reduce the computing time required. The available data for the Jakobshavn Glacier region was for bed elevation only; To calculate thicknesses from these bed elevations, the bed elevations were subtracted from surface elevations obtained using a bicubic spline of 5km gridded surface data from NSIDC.
presartm  
long_name   Annual Mean Air Temperature (2 meter)
standard_name   air_temperature
units   degree_Celsius
grid_mapping   mapping
source   Janneke Ettema; Institute for Marine and Atmospheric Research, Utrecht University, Utrecht, Netherlands
reference   Ettema J., M.R. van den Broeke, E. van Meigaard, W.J. van de Berg, J.L. Bamber, J.E. Box, and R.C. Bales (2009), Higher surface mass balance of the Greenland ice sheet revealed by high-resolution climate modeling, Geophys. Res. Lett., 36, L12501, doi:10.1029/2009GL038110
comments   Natgridd's linear natural neighbor algorithm was used for interpolation.
presprcp  
long_name   Present Precipitation
standard_name   lwe_precipitation_rate
units   meters/year
grid_mapping   mapping
source   Janneke Ettema; Institute for Marine and Atmospheric Research, Utrecht University, Utrecht, Netherlands
reference   Ettema J., M.R. van den Broeke, E. van Meigaard, W.J. van de Berg, J.L. Bamber, J.E. Box, and R.C. Bales (2009), Higher surface mass balance of the Greenland ice sheet revealed by high-resolution climate modeling, Geophys. Res. Lett., 36, L12501, doi:10.1029/2009GL038110
comments   Natgridd's linear natural neighbor algorithm was used for interpolation.
bheatflx  
long_name   Basal Heat Flux
standard_name   upward_geothermal_flux_at_ice_base
units   watts/meter^2
grid_mapping   mapping
source   http://ciei.colorado.edu/~nshapiro/MODEL/ASC_VERSION/index.html
reference   Shapiro, N.M. and Ritzwoller, M.H. (2004), Inferring Surface Heat Flux Distributions Guided by a Global Seismic Model: Particular Application to Antarctica; Earth and Planetary Science letters, 223: 213-224.
comments   Natgridd's linear natural neighbor algorithm was used for interpolation.

* A description of recent changes to this and other data sets can be found in the change log.