GRIP Ice Core Dielectric Profiling and Electrical Conductivity Data Wolff, E.W.; Moore, J.C.; Clausen, H.B.; Hammer, C.U. Wolff, E.W. Moore, J.C. Clausen, H.B. Hammer, C.U. earth science/paleoclimate/ice cores (depth at sample start,null,null,meter,null,ice cores,null,null,N,null) earth science/paleoclimate/ice cores (ice age at sample start,null,null,calendar year before present,null,ice cores,null,null,N,null) earth science/paleoclimate/ice cores (electrical conductivity,bulk ice,null,micromole,null,ice cores,null,direct current electrical conductivity measurement,N,null) earth science/paleoclimate/ice cores (electrical conductivity,bulk ice,null,microequivalent per kilogram,null,ice cores,null,direct current electrical conductivity measurement,N,null) earth science/paleoclimate/ice cores (electrical conductivity,bulk ice,null,microsiemens per meter,null,ice cores,null,dielectric profiling,N,null) earth science/paleoclimate/ice core (GRIP>LATITUDE 72.58>LONGITUDE -37.63) High-resolution continuous profiles were obtained on the Greenland Ice Core Project (GRIP) ice core using two different electrical methods. After correction for temperature and density, the electrical conductivity method (ECM) technique responds only to acidity, while dielectric profiling (DEP) responds to acid, ammonium, and chloride. Detailed chemistry on a section of glacial-age ice allows us to confirm the calibration factor for chloride in DEP. Acidity dominates the DEP variability in the Holocene, Allerod/Bolling, and larger interstadials; ammonium dominates in the Younger Dry as, while chloride is the major contributor in cold periods including smaller interstadials. From the electrical signals plotted on a linear timescale we can deduce the background (nonvolcanic) acidity of the ice, varying from always acidic in the Holocene to always alkaline in the cold periods. In the interstadials, the ice is close to neutral, with most of it acidic in larger interstadials, most of it alkaline in smaller ones, and rapid alternations within interstadials. It is not clear whether neutralization of individual acidic particles occurred in the atmosphere or whether acid and alkaline particles coexisted until deposition in the snowpack. The changes in acidity observed at GRIP apply at least to all of Greenland and probably to much of North America. There would have been ecological effects and important changes in the uptake of some chemicals onto ice. If acidic sulfate particles were neutralized and removed from the atmosphere, which remains uncertain, then there are atmospheric chemistry and radiative effects that require further investigation. STUDY NOTES: GRIP Ice Core Dielectric Profiling (DEP) and Electrical Conductivity (ECM) Data. The files dep1.dat, dep2.dat, etc. contain DEP (dielectric profiling) data from the GRIP ice core drilled at Summit, Greenland at 2 cm resolution. The file gripdep.dat contains averages over a 55 cm interval. The ECM values were originally gathered continuously for every 1 cm of the core, but in file are averaged in 55cm intervals. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Wolff, E.W. Investigator : Moore, J.C. Investigator : Clausen, H.B. Investigator : Hammer, C.U. 1997-11-30 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/17845 https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/ https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep1.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep10.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/gripecm.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep3.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep7.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/gripdep.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep5.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep8.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/depinfo.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep2.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep9.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep4.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep6.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/ https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep1.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep10.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/gripecm.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep3.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep7.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/gripdep.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep5.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep8.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/depinfo.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep2.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep9.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep4.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep6.dat English https://www.ncdc.noaa.gov/paleo/study/17845 https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/ https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep1.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep10.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/gripecm.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep3.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep7.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/gripdep.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep5.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep8.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/depinfo.txt https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep2.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep9.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep4.dat https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/grip/ecm/dep6.dat Eric W. Wolff, John C. Moore, Henrik B. Clausen, Claus U. Hammer1997Climatic implications of background acidity and other chemistry derived from electrical studies of the Greenland Ice Core Project ice coreJournal of Geophysical Research: Oceans102C1226325-2633210.1029/96JC02223http://onlinelibrary.wiley.com/enhanced/doi/10.1029/96JC02223/ START YEAR: 247618 cal yr BP * END YEAR: 466 cal yr BP -37.63 72.58 -37.63 72.58