Climate over past millennia

P. D. Jones, Michael Mann

Research output: Contribution to journalArticle

605 Citations (Scopus)

Abstract

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 past 1 to 2 millennia. We assess reconstructions and modeling studies analyzing a number of different climate fields, including atmospheric circulation diagnostics, precipitation, and drought. We devote particular attention to proxy-based reconstructions of temperature patterns in past centuries, which place recent large-scale warming in an appropriate longer-term context. Our assessment affirms the conclusion that late 20th century warmth is unprecedented at hemispheric and, likely, global scales. There is more tentative evidence that particular modes of climate variability, such as the El Niño/Southern Oscillation and the North Atlantic Oscillation, may have exhibited late 20th century behavior that is anomalous in a long-term context. Regional conclusions, particularly for the Southern Hemisphere and parts of the tropics where high-resolution proxy data are sparse, are more circumspect. The dramatic differences between regional and hemispheric/ global past trends, and the distinction between changes in surface temperature and precipitation/drought fields, underscore the limited utility in the use of terms such as the "Little Ice Age" and "Medieval Warm Period" for describing past climate epochs during the last millennium. Comparison of emphirical evidence with proxy-based reconstructions demonstrates that natural factors appaear to explain relatively well the major surface temperature changes of the past millennium through the 9th century (including hemispheric means and some spatial patterns). Only anthropogenic forcing of climate, however, can explain the recent anomalous warming in the late 20th century.

Original languageEnglish (US)
JournalReviews of Geophysics
Volume42
Issue number2
DOIs
StatePublished - Jun 1 2004

Fingerprint

climate
drought
surface temperature
warming
Medieval Warm Period
Southern Oscillation
Little Ice Age
North Atlantic Oscillation
atmospheric circulation
heating
high resolution
Southern Hemisphere
climate change
climate modeling
tropical regions
ice
time measurement
trends
oscillations
modeling

All Science Journal Classification (ASJC) codes

  • Geophysics

Cite this

Jones, P. D. ; Mann, Michael. / Climate over past millennia. In: Reviews of Geophysics. 2004 ; Vol. 42, No. 2.
@article{204ca3536c3a4243bc22c202f74bb44d,
title = "Climate over past millennia",
abstract = "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 past 1 to 2 millennia. We assess reconstructions and modeling studies analyzing a number of different climate fields, including atmospheric circulation diagnostics, precipitation, and drought. We devote particular attention to proxy-based reconstructions of temperature patterns in past centuries, which place recent large-scale warming in an appropriate longer-term context. Our assessment affirms the conclusion that late 20th century warmth is unprecedented at hemispheric and, likely, global scales. There is more tentative evidence that particular modes of climate variability, such as the El Ni{\~n}o/Southern Oscillation and the North Atlantic Oscillation, may have exhibited late 20th century behavior that is anomalous in a long-term context. Regional conclusions, particularly for the Southern Hemisphere and parts of the tropics where high-resolution proxy data are sparse, are more circumspect. The dramatic differences between regional and hemispheric/ global past trends, and the distinction between changes in surface temperature and precipitation/drought fields, underscore the limited utility in the use of terms such as the {"}Little Ice Age{"} and {"}Medieval Warm Period{"} for describing past climate epochs during the last millennium. Comparison of emphirical evidence with proxy-based reconstructions demonstrates that natural factors appaear to explain relatively well the major surface temperature changes of the past millennium through the 9th century (including hemispheric means and some spatial patterns). Only anthropogenic forcing of climate, however, can explain the recent anomalous warming in the late 20th century.",
author = "Jones, {P. D.} and Michael Mann",
year = "2004",
month = "6",
day = "1",
doi = "10.1029/2003RG000143",
language = "English (US)",
volume = "42",
journal = "Reviews of Geophysics",
issn = "8755-1209",
publisher = "American Geophysical Union",
number = "2",

}

Climate over past millennia. / Jones, P. D.; Mann, Michael.

In: Reviews of Geophysics, Vol. 42, No. 2, 01.06.2004.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Climate over past millennia

AU - Jones, P. D.

AU - Mann, Michael

PY - 2004/6/1

Y1 - 2004/6/1

N2 - 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 past 1 to 2 millennia. We assess reconstructions and modeling studies analyzing a number of different climate fields, including atmospheric circulation diagnostics, precipitation, and drought. We devote particular attention to proxy-based reconstructions of temperature patterns in past centuries, which place recent large-scale warming in an appropriate longer-term context. Our assessment affirms the conclusion that late 20th century warmth is unprecedented at hemispheric and, likely, global scales. There is more tentative evidence that particular modes of climate variability, such as the El Niño/Southern Oscillation and the North Atlantic Oscillation, may have exhibited late 20th century behavior that is anomalous in a long-term context. Regional conclusions, particularly for the Southern Hemisphere and parts of the tropics where high-resolution proxy data are sparse, are more circumspect. The dramatic differences between regional and hemispheric/ global past trends, and the distinction between changes in surface temperature and precipitation/drought fields, underscore the limited utility in the use of terms such as the "Little Ice Age" and "Medieval Warm Period" for describing past climate epochs during the last millennium. Comparison of emphirical evidence with proxy-based reconstructions demonstrates that natural factors appaear to explain relatively well the major surface temperature changes of the past millennium through the 9th century (including hemispheric means and some spatial patterns). Only anthropogenic forcing of climate, however, can explain the recent anomalous warming in the late 20th century.

AB - 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 past 1 to 2 millennia. We assess reconstructions and modeling studies analyzing a number of different climate fields, including atmospheric circulation diagnostics, precipitation, and drought. We devote particular attention to proxy-based reconstructions of temperature patterns in past centuries, which place recent large-scale warming in an appropriate longer-term context. Our assessment affirms the conclusion that late 20th century warmth is unprecedented at hemispheric and, likely, global scales. There is more tentative evidence that particular modes of climate variability, such as the El Niño/Southern Oscillation and the North Atlantic Oscillation, may have exhibited late 20th century behavior that is anomalous in a long-term context. Regional conclusions, particularly for the Southern Hemisphere and parts of the tropics where high-resolution proxy data are sparse, are more circumspect. The dramatic differences between regional and hemispheric/ global past trends, and the distinction between changes in surface temperature and precipitation/drought fields, underscore the limited utility in the use of terms such as the "Little Ice Age" and "Medieval Warm Period" for describing past climate epochs during the last millennium. Comparison of emphirical evidence with proxy-based reconstructions demonstrates that natural factors appaear to explain relatively well the major surface temperature changes of the past millennium through the 9th century (including hemispheric means and some spatial patterns). Only anthropogenic forcing of climate, however, can explain the recent anomalous warming in the late 20th century.

UR - http://www.scopus.com/inward/record.url?scp=4444301308&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=4444301308&partnerID=8YFLogxK

U2 - 10.1029/2003RG000143

DO - 10.1029/2003RG000143

M3 - Article

VL - 42

JO - Reviews of Geophysics

JF - Reviews of Geophysics

SN - 8755-1209

IS - 2

ER -