Particle concentration and size distribution in the NGRIP ice core ...

• Main Authors: Ruth, Urs, Steffensen, Jørgen Peder, Bigler, Matthias
• Format: Dataset
• Language: English
• Published: PANGAEA 2003
• Subjects: DEPTH, ice/snow; AGE; Depth, top/min; Depth, bottom/max; Age, minimum/young; Age, maximum/old; Particle concentration; Mass concentration; Mode, grain size; Standard deviation; Uncertainty of fit parameter; Sample comment; Ice drill; Calculated; NGRIP; Sampling/drilling ice; North Greenland Ice Core Project NGRIP; Greenland; Greenland ice core; Greenland Ice core Project; GRIP; ice core; North Greenland; North Greenland Ice Core Project
• Online Access: https://dx.doi.org/10.1594/pangaea.107444; https://doi.pangaea.de/10.1594/PANGAEA.107444

A novel laser microparticle detector used in conjunction with continuous sample melting has provided a more than 1500 m long record of particle concentration and size distribution of the NGRIP ice core, covering continuously the period approximately from 9.5-100 kyr before present; measurements were at 1.65 m depth resolution, corresponding to approximately 35-200 yr. Particle concentration increased by a factor of 100 in the Last Glacial Maximum (LGM) compared to the Preboreal, and sharp variations of concentration occurred synchronously with rapid changes in the delta18O temperature proxy. The lognormal mode µ of the volume distribution shows clear systematic variations with smaller modes during warmer climates and coarser modes during colder periods. We find µ ~ 1.7 µm diameter during LGM and µ ~ 1.3 µm during the Preboreal. On timescales below several 100 years µ and the particle concentration exhibit a certain degree of independence present especially during warm periods, when µ generally is more ... : The provisional depth scale was constructed by matching all D/O-transitions to the GRIP SS09 time scale and using a linear interpolation in between. ...