noaa-icecore-2447
Nevado Huascarán - Oxygen Isotope, NO3, Layer Thickness, and Particle Data
Thompson, L.G.; Mosley-Thompson, E.; Davis, M.D.; Lin, P-N.; Henderson, K.A.; Cole-Dai, J.; Bolzan, J.F.; Liu, K-B.
Nevado Huascarán - Oxygen Isotope, NO3, Layer Thickness, and Particle Data
2001-01-30
NCDC-Paleoclimatology
ONLINE Files
Pending
https://www.ncdc.noaa.gov/paleo/study/2447
Investigator
L.G.
Thompson
Investigator
E.
Mosley-Thompson
Investigator
M.D.
Davis
Investigator
P-N.
Lin
Investigator
K.A.
Henderson
Investigator
J.
Cole-Dai
Investigator
J.F.
Bolzan
Investigator
K-B.
Liu
earth science
paleoclimate
ice cores
ice age,null,null,year Common Era,null,ice cores,null,null,N,null
earth science
paleoclimate
ice cores
particles,bulk ice,null,count,null,ice cores,null,electric sensing particle size analysis,N,> 2 micrometers
earth science
paleoclimate
ice cores
particles,bulk ice,null,count,null,ice cores,averaged,electric sensing particle size analysis,N,null
earth science
paleoclimate
ice cores
nitrate,bulk ice,null,parts per billion,null,ice cores,averaged,ion chromatography,N,null
earth science
paleoclimate
ice cores
delta 18O,bulk ice,null,per mil SMOW,null,ice cores,averaged,isotope ratio mass spectrometry,N,null
earth science
paleoclimate
ice cores
delta 18O,bulk ice,null,per mil SMOW,null,ice cores,null,isotope ratio mass spectrometry,N,null
earth science
paleoclimate
ice cores
layer thickness,bulk ice,null,meter,null,ice cores,null,null,N,null
earth science
paleoclimate
ice cores
ice age at sample end,null,null,year Common Era,null,ice cores,null,null,N,null
earth science
paleoclimate
ice cores
particles,bulk ice,null,count,null,ice cores,null,electric sensing particle size analysis,N,> 0.63 micrometers
earth science
paleoclimate
ice cores
sulfate,bulk ice,null,parts per billion,null,ice cores,averaged,ion chromatography,N,null
earth science
paleoclimate
ice cores
density,bulk ice,null,unspecified unit,null,ice cores,null,null,N,null
earth science
paleoclimate
ice cores
nitrate,bulk ice,null,parts per billion,null,ice cores,null,ion chromatography,N,null
earth science
paleoclimate
ice cores
particles,bulk ice,null,count,null,ice cores,averaged,electric sensing particle size analysis,N,> 2 micrometers
earth science
paleoclimate
ice cores
depth,null,null,meter,null,ice cores,null,null,N,null
earth science
paleoclimate
ice cores
particles,bulk ice,null,count,null,ice cores,averaged,electric sensing particle size analysis,N,> 0.63 micrometers
earth science
paleoclimate
ice cores
ice age at sample start,null,null,year Common Era,null,ice cores,null,null,N,null
earth science
paleoclimate
ice cores
chloride,bulk ice,null,parts per billion,null,ice cores,averaged,ion chromatography,N,null
earth science
paleoclimate
ice core
physical properties
earth science
paleoclimate
ice core
oxygen isotopes
earth science
paleoclimate
ice core
chemistry
earth science
paleoclimate
ice core
instrumental data
geoscientificInformation
PAGES 2k Network
PAGES LOTRED SA2k
-17100 AD
1993 AD
19050 cal yr BP
-43 cal yr BP
Complete
-9
-9
-77.5
-77.5
6050
6050
Continent
South America
Peru
Nevado Huascarán>LATITUDE -9>LONGITUDE -77.5
None
Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site.
English
DOC/NOAA/NESDIS/NCEI
National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
https://www.ncdc.noaa.gov/data-access/paleoclimatology-data
DATA Center Contact
Bruce
Bauer
bruce.a.bauer@noaa.gov
paleo@noaa.gov
303-497-6280
303-497-6513
325 Broadway, E/NE31
Boulder
CO
80305-3328
USA
online
ASCII
Thompson, L.G., E. Mosley-Thompson, M.E. Davis,
P-N. Lin, K.A. Henderson, J. Cole-Dai, J.F. Bolzan and K-b. Liu. 1995. Late Glacial Stage and Holocene tropical ice core records from Huascarán, Peru. Science, Vol. 269, pp.46-50. DOI:10.1126/science.269.5220.46
Two ice cores from the col of Huascarán in the north-central Andes of Peru contain a paleoclimatic history extending well into the Wisconsinan (Würm) Glacial Stage and include evidence of the Younger Dryas cool phase. Glacial stage conditions at high elevations in the tropics appear to have been as much as 8° to 12°C cooler than today, the atmosphere contained about 200 times as much dust, and the Amazon Basin forest cover may have been much less extensive. Differences in both the oxygen isotope ratio d18O (8 per mil) and the deuterium excess (4.5 per mil) from the Late Glacial Stage to the Holocene are comparable with polar ice core records. These data imply that the tropical Atlantic was possibly 5° to 6°C cooler during the Late Glacial Stage, that the climate was warmest from 8400 to 5200 years before present, and that it cooled gradually, culminating with the Little Ice Age (200 to 500 years before present). A strong warming has dominated the last two centuries.
STUDY NOTES: General Information about the Huascarán Ice Cores
Site Description and Analysis
In July-August 1993, two ice cores to bedrock were recovered from the col
between the north and south peaks of Nevado Huascarán, Peru (9øS, 77ø30'W, col
elevation 6050 m) and were subsequently transported back to the cold room facility at the
Byrd Polar Research Center (BPRC). Core 1 (HSC1, 160.40 m) was sectioned in the
field into 2677 samples decreasing in thickness from 13 cm at the top to 3 cm at the base,
which were then melted and poured into 2 or 4 oz. plastic (HDPE) bottles, and sealed
with wax. Core 2 (HSC2, 166.08 m), drilled approximately 100 m from the HSC1 site,
was returned frozen in 1 m sections. Ice motion vectors determined from stake
movements from 1991-93 indicate that the drill sites are proximal to the divide between
ice flow towards the east and west outlets of the col. Visible observations and borehole
temperatures indicate that the glacier is 'polar' type, i.e., it remains frozen to the bed
(Thompson et al., Science, v.269, 1995, p. 46-50).
Each ice sample from HSC2 was prepared in a Class 100 clean room
environment, and analyzed for major anion concentrations (Cl-, NO3-, and SO42-) on a
Dionex 2010i ion chromatograph, d18O on a Finnigan Mat mass spectrometer (Craig,
1957), and for particulate concentration and size distribution using a Coulter TA-II
particle counter (Thompson, OSU IPS Report 46, 1973). A complete d18O profile was
also produced from the bottled samples from HSC1. Contamination during field
preparation and transport of these samples precluded the development of a second
complete record of particles and anion concentrations.
For display purposes, variable averaging on the core depth scale was utilized to
show the major large-scale events in the record without the confusion of the large annual
variations superimposed upon the upper portion. Hence, for HSC2, 5-m integrated
averages were calculated for between the surface and 140 meters depth and then 50-cm
averages were generated between 140 and 160 meters. Between 160 and 166 meters,
every sample value was plotted. A similar scheme was used for HSC1 (all values plotted
for 155-160.4 m). These data are included in hs12-5m.txt in this data archive, and the
graph can be seen in Thompson et al., 1995 (Fig. 3).
Development of the time/depth relationship
Tropical South American climate is marked by annual dry seasons (July-October)
which were identifiable in the ice core record as elevated values in all relevant
measurements. The nitrate (NO3-) record from the Huascarán ice core provided the most
definitive seasonal marker, but the final time scale was constructed from a comparison of
four major parameters (NO3-, d18O, dust and SO42-). Each annual maximum corresponds
to the middle of the dry season, assumed to occur on the 1st of August. The rapid layer-
thinning below 120 m limited annual resolution to the most recent 270 years. However,
the high accumulation and strong preservation of seasonal cycles also made possible the
subannual resolution of d18O variations for a period of at least 100 years (1894-1993).
The accuracy of the time scale is of paramount importance in the development of
relationships between ice core proxy data and tropical climate conditions. Several
horizons in recent times were useful for confirming the layer counting as a reliable
method, and indicate almost certain ages for the uppermost 50 years. In 1980, during the
original reconnaissance expedition to Huascarán, a 10 m firn core was extracted and
analyzed for d18O at BPRC (Thompson et al., JGR, v. 89d3, 1984, p. 4638-4646). Aside
from minor accumulation variation and slight signal attenuation, the 1993 cores
duplicated the earlier stable isotope profile over the common portion, and confirmed the
layer counting to 1980 as absolute. Additionally, a magnitude 7.7 earthquake struck
coastal Peru in May 1970, generating large mud flows following the collapse of a large
portion of the Huascarán glacier from the north peak. The event was recognized in the ice
core by a sharp two-year rise in particulates from the newly-created sediment source. A
third time horizon was provided by the HSC2 36Cl profile (Synal et al., Glaciers From the
Alps, Paul Scherrer Inst., 1997, p. 99-102), a substance produced by neutron activation
during the explosion of atomic devices in the presence of a 35Cl source, such as sea water.
An abrupt >100-fold rise in 36Cl concentration occurred at ~54 m depth, which dates (by
layer counting) to 1951-53. This was in direct response to the October 31, 1952 U.S.
'Ivy' surface test of an experimental nuclear device on the Eniwetok Atoll in the Pacific
Ocean (11øN, 162øE) (Carter and Moghissi, Health Physics, v. 33, 1977, p. 55-71).
Finally, in both HSC1 and HSC2, the 1883 eruption of Krakatau, Indonesia (6øS,
105ø30'E) was identified by an anomalous sulfate concentration of ~400 ppb at 110 m
depth, more than twice the level of any other local (within 10 m) event. A date of mid-
year 1884 was thus considered to be an absolute time marker for both cores within the
error of the time lag (less than one year).
GET DATA
https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/trop/huascaran/readme_huascaran.txt
GET DATA
https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/trop/huascaran/hs12-5m.txt
GET DATA
https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/trop/huascaran/annualc.txt
GET DATA
https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/trop/huascaran/hs2layer.txt
GET DATA
https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/trop/huascaran/all-mo.txt
GET DATA
https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/trop/huascaran/hs1layer.txt
GET DATA
https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/trop/huascaran/age.txt
GET DATA
https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/trop/huascaran/anions.txt
GET DATA
https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/trop/huascaran/hs2-100a.txt
GET DATA
https://www1.ncdc.noaa.gov/pub/data/paleo/icecore/trop/huascaran/annualt.txt
USA/NOAA
DIF
Version 9.8.4
2018-12-11
2018-12-11