Northern Hemisphere Surface Temperature Reconstruction Sensitivity Comparisons
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                NOAA Paleoclimatology Program
                               and
         World Data Center for Paleoclimatology, Boulder
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NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!!


NAME OF DATA SET: 
Northern Hemisphere Surface Temperature Reconstruction Sensitivity Comparisons
LAST UPDATE: 8/2005 (Original Receipt by WDC Paleo)

CONTRIBUTOR: Scott Rutherford, Roger Williams University
IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2005-057

SUGGESTED DATA CITATION: Rutherford, S., et al. 2005.
Northern Hemisphere Surface Temperature Reconstruction Sensitivity Comparisons.
IGBP PAGES/World Data Center for Paleoclimatology 
Data Contribution Series #2005-057. 
NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. 


ORIGINAL REFERENCE: Rutherford, S., M.E. Mann, T.J. Osborn, R.S. Bradley, 
K.R. Briffa, M.K. Hughes, and P.D. Jones.  2005.
Proxy-Based Northern Hemisphere Surface Temperature Reconstructions: 
Sensitivity to Method, Predictor Network, Target Season, and Target Domain.
Journal of Climate, Vol. 18, No. 13, pp. 2308–2329, July 2005.
doi: 10.1175/JCLI3351.1


ABSTRACT:
Results are presented from a set of experiments designed to investigate factors 
that may influence proxy-based reconstructions of large-scale temperature patterns 
in past centuries. The factors investigated include 1) the method used to 
assimilate proxy data into a climate reconstruction, 2) the proxy data network used, 
3) the target season, and 4) the spatial domain of the reconstruction. Estimates of 
hemispheric-mean temperature are formed through spatial averaging of reconstructed 
temperature patterns that are based on either the local calibration of proxy and 
instrumental data or a more elaborate multivariate climate field reconstruction 
approach. The experiments compare results based on the global multiproxy dataset 
used by Mann and coworkers, with results obtained using the extratropical Northern 
Hemisphere (NH) maximum latewood tree-ring density set used by Briffa and coworkers. 
Mean temperature reconstructions are compared for the full NH (Tropics and extratropics, 
land and ocean) and extratropical continents only, with varying target seasons 
(cold-season half year, warm-season half year, and annual mean). The comparisons 
demonstrate dependence of reconstructions on seasonal, spatial, and methodological 
considerations, emphasizing the primary importance of the target region and seasonal 
window of the reconstruction. The comparisons support the generally robust nature of 
several previously published estimates of NH mean temperature changes in past centuries 
and suggest that further improvements in reconstructive skill are most likely to arise 
from an emphasis on the quality, rather than quantity, of available proxy data.


GEOGRAPHIC REGION: Northern Hemisphere
PERIOD OF RECORD:  1400-1971 AD

DESCRIPTION: 
Comparison of the sensitivity of Northern Hemisphere temperature reconstructions, 
using 2 individual proxy networks and the 2 networks combined.

MXD is the Briffa tree ring maximum density network. 
Multiproxypc is the Mann, Bradley and Hughes 1998 multi-proxy network.
Combined includes both networks. 

Comparisons are based on the season and domain of the reconstruction. 
Seasons: warm (april-sept), cold (oct-mar) and ann (annual calendar mean). 
Domain: Fullnh is the full northern hemisphere, landextratrop is the 
land-only extratropical northern hemisphere, and 
osbmask is the Osborn reconstruction mask (see manuscript for details).