# PAGES Antarctica2k Temperature Reconstructions
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#                World Data Service for Paleoclimatology, Boulder 
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#                     NOAA Paleoclimatology Program 
#             National Centers for Environmental Information (NCEI)
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# Template Version 3.0
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# NOTE: Please cite Publication, and Online_Resource and date accessed when using these data. 
# If there is no publication information, please cite Investigators, Title, and Online_Resource and date accessed. 
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# Online_Resource: https://www.ncdc.noaa.gov/paleo/study/22589 
#       Description: NOAA Landing Page
# Online_Resource: https://www1.ncdc.noaa.gov/pub/data/paleo/pages2k/stenni2017antarctica/readme-stenni2017ant2k.txt
#       Description: NOAA location of the template
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# Original_Source_URL:  
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# Description/Documentation lines begin with #
# Data lines have no #
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# Archive: Ice Core
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# Dataset DOI: 
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# Parameter_Keywords: oxygen isotopes, accumulation, reconstruction
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# Contribution_Date
#	Date: 2017-11-17
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# File_Last_Modified_Date
#	Date: 2017-11-17
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# Title
#	Study_Name: PAGES Antarctica2k Temperature Reconstructions
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# Investigators
#	Investigators: Stenni, B.; Curran, M.A.J.; Abram, N.J.; Orsi, A.J.; Goursaud, S.; Masson-Delmotte, V.; Neukom, R.; Goosse, H.; Divine, D.V.; van Ommen, T.D.; Steig, E.J.; Dixon, D.A.; Thomas, E.R.; Bertler, N.A.N.; Isaksson, E.; Ekaykin, A.A.; Werner, M.; Frezzotti, M. 
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# Description_Notes_and_Keywords
#	Description: Antarctic ice core proxy data and temperature reconstructions for the past 2,000 years. 
#	When using these data refer to Stenni et al. 2017, Clim. Past, 13:1609 doi: 10.5194/cp-13-1609-2017 
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#	Online data folder /DMLicecore/ contains the Dronning Maud Land ice core d18O and accumulation data. 
#	Online data folder /CPSrecons/ contains the CPS reconstructions for all sub-regions
# 	Data file Ant2K_2017_isotopic and temperature_data.xlsx, and its text export files, contain the regional compilations as follows:
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# variable	bin size	dataset used for weighting	temperature scaling method	Figure used	Filename
# isotope anomalies	5y averages	no weighting	na	Fig 2 	stenni2017fig2aR5d-unweighted.txt, stenni2017fig2aR5d-unweighted-stats.txt, stenni2017fig2aR5d-unweighted.txt
# isotope anomalies	5y averages	NB2014	na	Fig 2 	stenni2017fig2bR5d-NB2014weight.txt
# isotope anomalies	5y averages	ECHAM5-wiso, d18O field	na	Fig 2 	stenni2017fig2cR5d-ECHAMisoweight.txt
# isotope anomalies	5y averages	ECHAM5-wiso, T field	na	Suppl. 	stenni2017suppl2dR5d-ECHAMTweight.txt
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# isotope anomalies	10y averages	no weighting	na	Fig 3	stenni2017fig3aR10d-unweighted.txt, stenni2017fig3aR10d-unweighted-stats.txt
# isotope anomalies	10y averages	NB2014	na	Fig 3	stenni2017fig3bR10d-NB2014weight.txt
# isotope anomalies	10y averages	ECHAM5-wiso, d18O field	na	Fig 3	stenni2017fig3cR10d-ECHAMisoweight.txt
# isotope anomalies	10y averages	ECHAM5-wiso, T field	na	Suppl. 	stenni2017suppl3dR10d-ECHAMTweight.txt
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# temperature anomalies	5y averages	NB2014	ECHAM5-wiso d18O-T relationship	Fig 4	stenni2017fig4aR5T-ECHscaling.txt
# temperature anomalies	5y averages	NB2014	NB2014 variance over 1960-1990	Fig 4	stenni2017fig4bR5T-NBscaling.txt
# temperature anomalies	5y averages	NB2014	ECHAM5 scaling corrected with WDC borehole temperature 	Fig 4	stenni2017fig4cR5T-Borehscaling.txt
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# temperature anomalies	10y averages	NB2014	ECHAM5-wiso d18O-T relationship	Fig 5 and 8	stenni2017fig5-8aR10T-ECHscaling.txt
# temperature anomalies	10y averages	NB2014	NB2014 variance over 1960-1990	Fig 5 and 8	stenni2017fig5-8bR10T-NBscaling.txt
# temperature anomalies	10y averages	NB2014	ECHAM5 scaling corrected with WDC borehole temperature 	Fig 5 and 8	stenni2017fig5-8cBorehscaling.txt
# temperature anomalies	10y averages	CPS	CPS	Fig 8	stenni2017fig8dR10Tcps.txt
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# Tab Fig6	statistics of the 100 year trends as presented in Figure 6.				stenni2017fig6slopestat.txt
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# tab 10 and 11 contain the time series used for calculating the weights with the NB2014 dataset					
# tab10	time series of temperature anomalies for each of the 112 sites				stenni2017NB2014siteextraction.txt
# tab11	time series of the  temperature of the regional average.				stenni2017NB2014regionalmean.txt
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# Publication 
#	Authors: Barbara Stenni, Mark A.J. Curran, Nerilie J. Abram, Anais Orsi, Sentia Goursaud, Valerie Masson-Delmotte, Raphael Neukom, Hugues Goosse, Dmitry Divine, Tas van Ommen, Eric J. Steig, Daniel A. Dixon, Elizabeth R. Thomas, Nancy A.N. Bertler, Elisabeth Isaksson, Alexey Ekaykin, Martin Werner, and Massimo Frezzotti 
#	Published_Date_or_Year: 2017-11-20   
#	Published_Title: Antarctic climate variability on regional and continental scales over the last 2000 years
#	Journal_Name: Climate of the Past
#	Volume: 13
#	Edition: 
#	Issue: 11
#	Pages: 1609-1634
#	Report_Number: 
#	DOI: 10.5194/cp-13-1609-2017 
#	Online_Resource: https://www.clim-past.net/13/1609/2017/
#	Full_Citation: 
#	Abstract: Climate trends in the Antarctic region remain poorly characterized, owing to the brevity and scarcity of direct climate observations and the large magnitude of interannual to decadal-scale climate variability. Here, within the framework of the PAGES Antarctica2k working group, we build an enlarged database of ice core water stable isotope records from Antarctica, consisting of 112 records. We produce both unweighted and weighted isotopic (d18O) composites and temperature reconstructions since 0?CE, binned at 5- and 10-year resolution, for seven climatically distinct regions covering the Antarctic continent. Following earlier work of the Antarctica2k working group, we also produce composites and reconstructions for the broader regions of East Antarctica, West Antarctica and the whole continent. We use three methods for our temperature reconstructions: (i) a temperature scaling based on the d18O-temperature relationship output from an ECHAM5-wiso model simulation nudged to ERA-Interim atmospheric reanalyses from 1979 to 2013, and adjusted for the West Antarctic Ice Sheet region to borehole temperature data, (ii) a temperature scaling of the isotopic normalized anomalies to the variance of the regional reanalysis temperature and (iii) a composite-plus-scaling approach used in a previous continent-scale reconstruction of Antarctic temperature since 1 CE but applied to the new Antarctic ice core database. Our new reconstructions confirm a significant cooling trend from 0 to 1900 CE across all Antarctic regions where records extend back into the 1st millennium, with the exception of the Wilkes Land coast and Weddell Sea coast regions. Within this long-term cooling trend from 0 to 1900 CE, we find that the warmest period occurs between 300 and 1000 CE, and the coldest interval occurs from 1200 to 1900 CE. Since 1900 CE, significant warming trends are identified for the West Antarctic Ice Sheet, the Dronning Maud Land coast and the Antarctic Peninsula regions, and these trends are robust across the distribution of records that contribute to the unweighted isotopic composites and also significant in the weighted temperature reconstructions. Only for the Antarctic Peninsula is this most recent century-scale trend unusual in the context of natural variability over the last 2000 years. However, projected warming of the Antarctic continent during the 21st century may soon see significant and unusual warming develop across other parts of the Antarctic continent. The extended Antarctica2k ice core isotope database developed by this working group opens up many avenues for developing a deeper understanding of the response of Antarctic climate to natural and anthropogenic climate forcings. The first long-term quantification of regional climate in Antarctica presented herein is a basis for data-model comparison and assessments of past, present and future driving factors of Antarctic climate.
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# Funding_Agency 
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# Site_Information 
#	Site_Name: Antarctica
#	Location: Antarctica
#	Country:  
#	Northernmost_Latitude: -60
# 	Southernmost_Latitude: -90
# 	Easternmost_Longitude: 180
# 	Westernmost_Longitude: -180
# 	Elevation:  
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# Data_Collection   
#	Collection_Name: Stenni2017Ant2k
#	Earliest_Year:  0
#	Most_Recent_Year:  2000
#	Time_Unit:  CE
#	Core_Length: 
#	Notes: 
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# Chronology_Information
#	Chronology: 
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