Figure 3.
2650-year (BC665-AD1985) WTR spliced with Beijing instrumental data from 1930-2000.
Solid red line is reconstructed MJJA temperature. Dark blue dashed line is errors.
Pink dashed line is observed MJJA data. The 101-year low-pass filter (green solid line)
shows centennial-scale variation. The zero line (light blue dashed) corresponds to the
overall mean of the reconstructed series. Thick and long arrows with capital letters
W and C point out the "absolute" warm peaks (upward) and cool troughs (downward),
respectively, at which temperature exceeds the average. Thin and short arrows with small
letter w and c point out the "relative" warm peaks and cool troughs, respectively,
at which temperature doesn't exceed the average.
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Cyclic rapid warming on centennial-scale revealed by a 2650-year stalagmite record of warm season temperature
Geophysical Research Letters
Vol. 30, No. 12, 1617 (June 2003).
Ming Tan and Tungsheng Liu
Institute of Geology and Geophysics, Chinese Academy of Sciences,
Beijing, China
State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences,
Shaanxi, China
Juzhi Hou and Xiaoguang Qin
Institute of Geology and Geophysics, Chinese Academy of Sciences,
Beijing, China
Hucai Zhang
Department of Geographical Sciences, Lanzhou University,
Lanzhou, China
Tieying Li
Beijing Geological Survey Institute,
Beijing, China
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A 2650-year (BC665-AD1985) warm season (MJJA: May, June, July, August) temperature reconstruction
is derived from a correlation between thickness variations in annual layers of a stalagmite from
Shihua Cave, Beijing, China and instrumental meteorological records. Observations of soil CO2
and drip water suggest that the temperature signal is amplified by the soil-organism-CO2 system
and recorded by the annual layer series. Our reconstruction reveals that centennial-scale rapid warming
occurred repeatedly following multicentennial cooling trends during the last millennia.
These results correlate with different records from the Northern Hemisphere, indicating that the
periodic alternation between cool and warm periods on a sub-millennial scale had a sub-hemispherical influence.
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