GISP2 Insoluble microparticles



Document Type

Data Set

Publication Date



Earth Sciences | Environmental Sciences

Description or Abstract

Insoluble microparticle concentrations and grain-size distributions are measured with an Elzone 280PC particle counter in a Class 100 clean room at the University of New Hampshire. The Elzone uses a 30 um orifice to measure microparticle concentrations in 64 logarithmically- divided channels from 0.65 um to 11 um and calculates a grain-size distribution as an equivalent spherical diameter. Mass values were calculated assuming an average density of 2.65 g/cm3. Mean grain size is based on the number of particles. We have also used mean grain size based on mass as discussed in Zielinski and Mershon [in press]. Beta values are the slope of the best-fit line of the grain-size distribution on a logarithmic scale by channel measured with lower beta values reflecting an overall coarser grain-size distribution and a higher beta value reflecting an overall finer grain-size distribution. Because some channels can have zero counts in them, the beta value may not be a reliable proxy of the overall coarseness/fineness of a sample. We do not use it in our interpretation of the insoluble microparticle record, but it is provided here because it has been used in the past by other ice core investigators.



Public (open access)


First online date / posted date July, 16, 2019.


Creative Commons Attribution 3.0 Unported