Summary: | The snow/firn density subdataset of SUMup is the largest, containing over 830,000 point measurements of density at different depths. The measurement methods include different sized density cutters (generally from 100 - 1000 cc) used in snow pits, ice core sections, neutron-density methods, X-ray microfocus computer tomography, Gamma-ray attenuation and pycnometers. The majority of the observations (~94%) come from Greenland ice cores or snow pits. Antarctic data comprises ~6% of the snow density subdataset and is predominately from ice cores. The depth of the density measurements are recorded using two different methods, either the top and bottom depth or a midpoint depth. Fields of data include the date taken, latitude, longitude, start depth, stop depth, midpoint depth, density, error, elevation, method, and associated citation.
|