Evaluation of Tree Growth Relevant Atmospheric Circulation Patterns for Geopotential Height Field Reconstructions for Asia

2018 ◽  
Vol 31 (11) ◽  
pp. 4391-4401 ◽  
Author(s):  
Andrea Seim ◽  
Johannes A. Schultz ◽  
Christoph Beck ◽  
Achim Bräuning ◽  
Paul J. Krusic ◽  
...  
Keyword(s):  
Atmospheric Circulation ◽  
Tree Ring ◽  
Tree Rings ◽  
Tree Growth ◽  
Geopotential Height ◽  
Large Scale ◽  
Weather Conditions ◽  
Atmospheric Circulation Patterns ◽  
Circulation Patterns ◽  
Height Fields

Atmospheric circulations influence local and regional weather conditions and, thus, tree growth. To identify summer weather types relevant for tree growth, and their associated synoptic-scale circulation patterns, an atmospheric circulation tree ring index (ACTI) dataset, derived from 414 tree-ring sites across Asia spanning the period 1871–2010, was created. Modes of common variability in the ACTI dataset were compared with leading modes of observed summertime 500-hPa geopotential height. The first four ACTI modes (explaining 88% of the total variance) were associated with pressure centers over Eurasia, the tropics, and the Pacific Ocean. The high spatiotemporal resemblance between the leading circulation modes, derived from both tree rings and 500-hPa geopotential height fields, indicates a strong potential for reconstructing large-scale circulation patterns from tree rings in Asia. This would allow investigations of natural atmospheric circulation variability prior to anthropogenic climate change and provide a means to validate model simulations of climate predictions.

scholarly journals Large scale climate signals of a European oxygen isotope network from tree-rings – predominantly caused by ENSO teleconnections?

2020 ◽  
Author(s):  
Daniel F. Balting ◽  
Monica Ionita ◽  
Martin Wegmann ◽  
Gerhard Helle ◽  
Gerhard H. Schleser ◽  
...  
Keyword(s):  
Atmospheric Circulation ◽  
Tree Ring ◽  
Tree Rings ◽  
Large Scale ◽  
Southern Oscillation ◽  
Circulation Pattern ◽  
Isotopic Signature ◽  
Atmospheric Circulation Patterns ◽  
Climate Signals ◽  
Instrumental Records

Abstract. We investigate the annual variability of δ18O tree ring records from sites distributed all over Europe covering the last 400 years. An Empirical Orthogonal Function (EOF) analysis reveals two distinct modes of variability on the basis of the existing δ18O tree ring records. The first mode of δ18O variability is associated with anomaly patterns of the El Niño-Southern Oscillation (ENSO) and reflects a multi-seasonal climatic signal. The ENSO signal is visible for the last 130 years, but is found weak during the period 1600 to 1850 suggesting that the relationship between ENSO and the European climate may not stable over time. The second mode of δ18O variability, which captures an out-of-phase variability between northwestern and southeastern European δ18O tree ring records, is related to a regional summer atmospheric circulation pattern revealing a pronounced centre over the North Sea. Locally, the δ18O anomalies associated with this mode show the same (opposite) sign with temperature (precipitation). We infer that the investigation of large-scale atmospheric circulation patterns and related teleconnections far beyond instrumental records can be done with oxygen isotopic signature derived from tree rings. However, the European δ18Ocel tree network needs to be consolidated and updated, as well as additional research on the stationarity of reconstructed climate signals and the stationarity of teleconnections is advisable.

scholarly journals Large-scale climate signals of a European oxygen isotope network from tree rings

2021 ◽  
Vol 17 (3) ◽  
pp. 1005-1023
Author(s):  
Daniel F. Balting ◽  
Monica Ionita ◽  
Martin Wegmann ◽  
Gerhard Helle ◽  
Gerhard H. Schleser ◽  
...  
Keyword(s):  
Atmospheric Circulation ◽  
Tree Ring ◽  
Tree Rings ◽  
Large Scale ◽  
Southern Oscillation ◽  
Circulation Pattern ◽  
Isotopic Signature ◽  
Atmospheric Circulation Patterns ◽  
The North ◽  
Instrumental Records

Abstract. We investigate the climate signature of δ18O tree-ring records from sites distributed all over Europe covering the last 400 years. An empirical orthogonal function (EOF) analysis reveals two distinct modes of variability on the basis of the existing δ18O tree-ring records. The first mode is associated with anomaly patterns projecting onto the El Niño–Southern Oscillation (ENSO) and reflects a multi-seasonal climatic signal. The ENSO link is pronounced for the last 130 years, but it is found to be weak over the period from 1600 to 1850, suggesting that the relationship between ENSO and the European climate may not be stable over time. The second mode of δ18O variability, which captures a north–south dipole in the European δ18O tree-ring records, is related to a regional summer atmospheric circulation pattern, revealing a pronounced centre over the North Sea. Locally, the δ18O anomalies associated with this mode show the same (opposite) sign with temperature (precipitation). Based on the oxygen isotopic signature derived from tree rings, we argue that the prevailing large-scale atmospheric circulation patterns and the related teleconnections can be analysed beyond instrumental records.

scholarly journals Bomb Produced 14C Content in Tree Rings Grown at Different Latitudes

Radiocarbon ◽  
1986 ◽  
Vol 28 (2A) ◽  
pp. 346-349 ◽  
Author(s):  
Kai-Mei Dai ◽  
C Y Fan
Keyword(s):  
Atmospheric Circulation ◽  
Tree Rings ◽  
Atmospheric Circulation Patterns ◽  
Nuclear Bomb ◽  
Circulation Patterns ◽  
Bomb Test ◽  
The 1950S

The 14C content in 1961–1967 rings of each of three spruce pines grown at (68° N, 130° W), (47° 30' N, 129° 16' E) and (27° 13' N, 100° 20' E) were measured. Δ14C values of the three specimens rise dramatically from a common level (∼250‰) in 1961 to their respective maxima, 964‰, 909‰, and 743‰ in 1964 and then fall to a common level ∼680‰ in 1967. The observed Δ14C increase comes most likely from the nuclear bomb test of the USSR at 75° N in 1961, although there were many other tests since the 1950s. The different effects at different latitudes reflect the atmospheric circulation patterns in the stratosphere and the transport of 14C nuclei from the stratosphere to the troposphere.

scholarly journals Influence of atmospheric circulation patterns on the oxygen isotope ratio of tree rings in the Alpine region

2012 ◽  
Vol 117 (D5) ◽  
pp. n/a-n/a ◽  
Author(s):  
Matthias Saurer ◽  
Anne Kress ◽  
Markus Leuenberger ◽  
Katja T. Rinne ◽  
Kerstin S. Treydte ◽  
...  
Keyword(s):  
Oxygen Isotope ◽  
Atmospheric Circulation ◽  
Tree Rings ◽  
Isotope Ratio ◽  
Alpine Region ◽  
Oxygen Isotope Ratio ◽  
Atmospheric Circulation Patterns ◽  
Circulation Patterns

scholarly journals Trends and variability in extreme precipitation indices over Maghreb countries

2013 ◽  
Vol 13 (12) ◽  
pp. 3235-3248 ◽  
Author(s):  
Y. Tramblay ◽  
S. El Adlouni ◽  
E. Servat
Keyword(s):  
Atmospheric Circulation ◽  
Large Scale ◽  
Heavy Precipitation ◽  
Climate Indices ◽  
Atmospheric Circulation Patterns ◽  
Circulation Patterns ◽  
Precipitation Indices ◽  
Precipitation Records ◽  
Mediterranean Oscillation ◽  
Large Scale Atmospheric Circulation

Abstract. Maghreb countries are highly vulnerable to extreme hydrological events, such as floods and droughts, driven by the strong variability of precipitation. While several studies have analyzed the presence of trends in precipitation records for the Euro-Mediterranean basin, this study provides a regional assessment of trends on its southernmost shores. A database of 22 stations located in Algeria, Morocco and Tunisia with between 33 and 59 yr of daily precipitation records is considered. The change points and trends are analyzed for eleven climate indices, describing several features of the precipitation regime. The issue of conducting multiple hypothesis tests is addressed through the implementation of a false discovery rate procedure. The spatial and interannual variability of the precipitation indices at the different stations are analyzed and compared with large-scale atmospheric circulation patterns, including the North Atlantic Oscillation (NAO), western Mediterranean Oscillation (WEMO), Mediterranean Oscillation (MO) and El Niño–Southern Oscillation (ENSO). Results show a strong tendency towards a decrease of precipitation totals and wet days together with an increase in the duration of dry periods, mainly for Morocco and western Algeria. On the other hand, only a few significant trends are detected for heavy precipitation indices. The NAO and MO patterns are well correlated with precipitation indices describing precipitation amounts, the number of dry days and the length of wet and dry periods, whereas heavy precipitation indices exhibit a strong spatial variability and are only moderately correlated with large-scale atmospheric circulation patterns.

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