TY - JOUR
T1 - Heterogeneous warming of Northern Hemisphere surface temperatures over the last 1200 years
AU - Tingley, Martin P.
AU - Huybers, Peter
N1 - Funding Information:
Proxy data are available through the NOAA Paleoclimatology portal at www.ncdc.noaa.gov/paleo/pubs/ moberg2005/moberg2005.html [Moberg et al., 2005] and www.ncdc. noaa.gov/paleo/pubs/osborn2006/ osborn2006.html [Osborn and Briffa, 2006]. The instrumental compilation is available at www.cru. uea.ac.uk/cru/data/temperature/. This work is supported in part by NSF P2C2 grant 1304309.
PY - 2015
Y1 - 2015
N2 - The relationship between the mean and spatial variability of Northern Hemisphere surface temperature anomalies over the last 1200 years is examined using instrumental and proxy records. Nonparametric statistical tests applied to 14 well-studied, annually resolved proxy records identify two centuries roughly spanning the Medieval Climate Anomaly as characterized by increased spatial variability relative to the preinstrumental baseline climate, whereas two centuries spanning the Little Ice Age are characterized by decreased spatial variability. Analysis of the instrumental record similarly indicates that the late and middle twentieth century warm intervals are generally associated with increased spatial variability. In both proxy and instrumental records an overall relationship between the first two moments is identified as a weak but significant positive correlation between time series of the spatial mean and spatial standard deviation of temperature anomalies, indicating that warm and cold anomalies are respectively associated with increased and reduced spatial variability. Insomuch as these historical patterns of relatively heterogeneous warming as compared with cooling hold, they suggest that future warming will feature increased regional variability.
AB - The relationship between the mean and spatial variability of Northern Hemisphere surface temperature anomalies over the last 1200 years is examined using instrumental and proxy records. Nonparametric statistical tests applied to 14 well-studied, annually resolved proxy records identify two centuries roughly spanning the Medieval Climate Anomaly as characterized by increased spatial variability relative to the preinstrumental baseline climate, whereas two centuries spanning the Little Ice Age are characterized by decreased spatial variability. Analysis of the instrumental record similarly indicates that the late and middle twentieth century warm intervals are generally associated with increased spatial variability. In both proxy and instrumental records an overall relationship between the first two moments is identified as a weak but significant positive correlation between time series of the spatial mean and spatial standard deviation of temperature anomalies, indicating that warm and cold anomalies are respectively associated with increased and reduced spatial variability. Insomuch as these historical patterns of relatively heterogeneous warming as compared with cooling hold, they suggest that future warming will feature increased regional variability.
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U2 - 10.1002/2014JD022506
DO - 10.1002/2014JD022506
M3 - Article
AN - SCOPUS:84930379527
VL - 120
SP - 4040
EP - 4056
JO - Journal of Geophysical Research: Atmospheres
JF - Journal of Geophysical Research: Atmospheres
SN - 2169-897X
IS - 9
ER -