Global Signatures and Dynamical Origins of the Little Ice Age and Medieval Climate Anomaly

  title={Global Signatures and Dynamical Origins of the Little Ice Age and Medieval Climate Anomaly},
  author={Michael Everett Mann and Zhihua Zhang and Scott David Rutherford and Raymond S. Bradley and Malcolm K. Hughes and Drew T. Shindell and Caspar Ammann and Gregory Faluvegi and Fenbiao Ni},
  pages={1256 - 1260}
Patterns of Change The global climate record of the past 1500 years shows two long intervals of anomalous temperatures before the obvious anthropogenic warming of the 20th century: the warm Medieval Climate Anomaly between roughly 950 and 1250 A.D. and the Little Ice Age between around 1400 and 1700 A.D. It has become increasingly clear in recent years, however, that climate changes inevitably involve a complex pattern of regional changes, whose inhomogeneities contain valuable insights into… 
The role of forcing and internal dynamics in explaining the “Medieval Climate Anomaly”
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Support for global climate reorganization during the “Medieval Climate Anomaly”
Widely distributed proxy records indicate that the Medieval Climate Anomaly (MCA; ~900–1350 AD) was characterized by coherent shifts in large-scale Northern Hemisphere atmospheric circulation
Dynamical anomalies in terrestrial proxies of North Atlantic climate variability during the last 2 ka
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Stability of weather regimes during the last millennium from climate simulations
[1] The variability of the extra-tropical atmospheric circulation and its potential dependence on external forcings have been debated topics in climate modeling and observation communities. A recent
Reconciling divergent trends and millennial variations in Holocene temperatures
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Characterization of the Medieval Climate Anomaly, Little Ice Age and recent warming in northern Lapland
The major climate events of the Common Era (CE) have global imprints but significant variations in their timing and magnitude have been suggested. For reliable assessments of the past climate
Regional Influences of Natural External Forcings on the Transition from the Medieval Climate Anomaly to the Little Ice Age
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Was the Little Ice Age more or less El Niño-like than the Medieval Climate Anomaly? Evidence from hydrological and temperature proxy data
Abstract. The El Nino–Southern Oscillation (ENSO) is the most important source of global climate variability on interannual timescales and has substantial environmental and socio-economic
Late Quaternary Climate History of Northern Europe
Understanding the full range of natural climate variability is a fundamental basis for palaeoclimate reconstruction and for estimating the magnitude of the anthropogenic influence on global change.
A volcanically triggered regime shift in the subpolar North Atlantic Ocean as a possible origin of the Little Ice Age
Abstract. Among the climatological events of the last millennium, the Northern Hemisphere Medieval Climate Anomaly succeeded by the Little Ice Age are of exceptional importance. The origin of these


Climate over past millennia
[1] We review evidence for climate change over the past several millennia from instrumental and high-resolution climate “proxy” data sources and climate modeling studies. We focus on changes over the
Tropical Pacific – mid-latitude teleconnections in medieval times
Terrestrial and marine late Holocene proxy records from the western and central US suggest that climate between approximately 500 and 1350 a.d. was marked by generally arid conditions with episodes
Volcanic and Solar Forcing of Climate Change during the Preindustrial Era
The climate response to variability in volcanic aerosols and solar irradiance, the primary forcings during the preindustrial era, is examined in a stratosphere-resolving general circulation model.
El Niño/Southern Oscillation and tropical Pacific climate during the last millennium
Fossil-coral oxygen isotopic records from Palmyra Island are splice together to provide 30–150-year windows of tropical Pacific climate variability within the last 1,100 years, implying that the majority of ENSO variability over the last millennium may have arisen from dynamics internal to the ENSo system itself.
Global-scale temperature patterns and climate forcing over the past six centuries
Spatially resolved global reconstructions of annual surface temperature patterns over the past six centuries are based on the multivariate calibration of widely distributed high-resolution proxy
Solar influence on climate during the past millennium: Results from transient simulations with the NCAR Climate System Model
A coupled climate system model was used to determine whether proxy-based irradiance series are capable of inducing climatic variations that resemble variations found in climate reconstructions, and if part of the previously estimated large range of past solar irradiance changes could be excluded.
Persistent Positive North Atlantic Oscillation Mode Dominated the Medieval Climate Anomaly
A 947-year-long multidecadal North Atlantic Oscillation reconstruction is presented and a persistent positive NAO is found during the Medieval Climate Anomaly to indicate a clear shift to weaker NAO conditions into the Little Ice Age (LIA).
Observed and simulated multidecadal variability in the Northern Hemisphere
Abstract Analyses of proxy based reconstructions of surface temperatures during the past 330 years show the existence of a distinct oscillatory mode of variability with an approximate time scale of
Influence of volcanic eruptions on Northern Hemisphere summer temperature over the past 600 years
A network of temperature-sensitive tree-ring-density chronologies provides circum-hemisphere information on year-by-year changes in summer warmth in different regions of the northern boreal forest.
Proxy-based reconstructions of hemispheric and global surface temperature variations over the past two millennia
The results extend previous conclusions that recent Northern Hemisphere surface temperature increases are likely anomalous in a long-term context to at least the past 1,700 years, but with additional strong caveats.