Mongolian Tree Rings and 20th-Century Warming

Japanese cedar rings sampled from Aomori Prefecture, Japan, were measured to obtain tree-ring radiocarbon data covering a period of the latter half of the 20th century in the northernmost area of Honshu (mainland Japan), to obtain records of variation in atmospheric 14C concentration caused by past atmospheric nuclear testing, and to study any possible local effects. This work, carried out on a partial disk, was also intended to provide a reference for data obtained by core sampling of live, standing Japanese black pines as a part of marine environmental studies.

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Long-term records of strontium isotopic composition in tree rings suggest changes in forest calcium sources in the early 20th century

Global Change Biology ◽

10.1111/j.1365-2486.2005.01034.x ◽

2005 ◽

Vol 0 (0) ◽

pp. 051006062331003-??? ◽

Cited By ~ 2

Author(s):

Thomas Drouet ◽

Jacques Herbauts ◽

Daniel Demaiffe

Keyword(s):

Isotopic Composition ◽

20Th Century ◽

Tree Rings ◽

Early 20Th Century ◽

Calcium Sources

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June–July Temperature Reconstruction of Kashmir Valley from Tree Rings of Himalayan Pindrow Fir

Atmosphere ◽

10.3390/atmos12030410 ◽

2021 ◽

Vol 12 (3) ◽

pp. 410

Author(s):

Rayees Malik ◽

Raman Sukumar

Keyword(s):

Climate Change ◽

20Th Century ◽

Tree Rings ◽

Volcanic Eruptions ◽

Summer Temperature ◽

Kashmir Valley ◽

Climate Records ◽

June July ◽

Site Chronology

The Himalaya is one of the major mountain ecosystems that is most likely to be impacted by climate change. The main drawback in understanding climate change in the remote Himalayan ecosystems is the lack of long-term instrumental climate records. Reconstructing past climates from tree-rings offers a useful proxy for adding data to the instrumental climate records. In this study, climatically sensitive tree-rings of Himalayan fir (Abies pindrow) were used for reconstruction of mean June–July temperatures of Kashmir valley. Total ring-width chronology was built from 60 tree-ring cores growing near the higher altitudinal limits of the species. The radial growth showed a strong positive response to growing season temperature. The strong response of site chronology to mean June–July temperatures was used for reconstruction purposes. Mean June–July temperatures of Kashmir valley were reconstructed since 1773 from residual site chronology. Though the reconstruction did not show any strong long-term trend, on a centennial-scale, 20th-century summers were the warmest with a mean annual summer temperature of 22.99 °C. Seven of the warmest years and five of the warmest decades were seen in the 20th century. The reconstruction for 1773–2012 showed 23 extreme hot summers above the hot threshold of a 23.47 °C mean temperature and 19 extreme cold years below the cold threshold of a 22.46 °C mean summer temperature. The cold years in the reconstruction did not coincide with known volcanic eruptions. This reconstruction will help in providing a better understanding of regional climate change.

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Tree rings of Pinus nigra from the Vienna basin region (Austria) show evidence of change in climatic sensitivity in the late 20th century

Canadian Journal of Forest Research ◽

10.1139/x07-189 ◽

2008 ◽

Vol 38 (4) ◽

pp. 744-759 ◽

Cited By ~ 35

Author(s):

Sofia Leal ◽

Derek Eamus ◽

Michael Grabner ◽

Rupert Wimmer ◽

Paolo Cherubini

Keyword(s):

Growth Rate ◽

20Th Century ◽

Tree Rings ◽

Tree Growth ◽

Water Availability ◽

Summer Precipitation ◽

Pinus Nigra ◽

Vienna Basin ◽

Late 20Th Century ◽

The Relationship

The width of tree rings of Pinus nigra Arn. trees growing near the ecological limits for the species, in the Vienna basin, Austria, showed a strong and positive correlation with spring–summer precipitation, indicating a dependence of growth on water availability during the growing season. During the late 20th century, tree rings grew wider than expected given the predicted relationship between rainfall and growth rate observed in the early 20th century. This resulted in models of the relationship between climate and growth rate systematically overestimating the total spring–summer (April–July) precipitation over the last half of the 20th century. Analysis of the temporal stability of the relationship between tree growth and climate variables shows a decrease in the sensitivity of the growth of tree rings to spring–summer precipitation towards the end of the 20th century. This change in sensitivity suggests that tree growth was no longer primarily dependent on water availability. We propose that there was an improvement in water-use efficiency arising from a stimulation of photosynthesis and declining stomatal conductance as a consequence of the increasing CO2 concentration in the atmosphere and that this effect was enhanced by a relatively high input of N due to the proximity of N emission sources.

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Burning Fossil Fuels Worsens Drought

Eos ◽

10.1029/2019eo122733 ◽

2019 ◽

Vol 100 ◽

Author(s):

Jenessa Duncombe

Keyword(s):

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

20Th Century ◽

Tree Rings ◽

Fossil Fuels ◽

Gas Emissions ◽

Drought Conditions

Tree rings help scientists trace the influence of greenhouse gas emissions on 20th-century drought conditions.

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Dendroclimatology as the Part of Dendrochronology

Man and Environment. Issues of Neoecology ◽

10.26565/1992-4224-2019-32-07 ◽

2019 ◽

Keyword(s):

Climate Change ◽

20Th Century ◽

Tree Rings ◽

Limiting Factors ◽

Weather Data ◽

Future Climate Change ◽

Forest Steppe ◽

Scientific Publications ◽

The Past ◽

Selection Of

As a the brench of dendrochronology, dendroclimatology assesses the climate in the past and uses tree rings and weather data, mainly precipitation and temperatures, to assess future climate change. The rate of publications on dendroclimatology was slow during the first half of the 20th century, but it has grown exponentially since the 1960s. More than 3,000 of the 12,000 scientific publications now listed in the dendrochronology's online bibliography contain the word "climate". The purpose of the paper is to review the history of dendro-climatology and its basic provisions. The American astronomer A.I. Douglas at the beginning of the 20th century developed the methods and principles that we use today. The basic principles of dendrochronology are borrowed from general ecology: the uniformitarian principle, the principle of limiting factors, the principle of aggregate tree growth, the principle of ecological emplitude, the principle of crossdating, the principle of cite celection. The basic methods in dendrochronology are: selection of research sites, selection of cores, cross-dating, indexation of tree-ring chronologies. Statistical methods for quantifying tree to climate ratios are briefly discussed, as well as correlation analysis and response function. Examples of dendroclimatological studies are given. F.G. Kolyshchuk proposed an original technique for the study of radial pine growth in the Carpathian Mountains. He found that during the last 200 - 230 years different species of pine (Pinus mughus Scop., Sembra L.) growing in the high mountains and inter-forested marshes (P. Silvestris L., P. Mughus Scop.) In the Ukrainian Carpathians it’s revealed a similar growth rate in tree rings, which may be evidence of climatic conditioning of the dynamics of growth and the same response of these pine species to climate change. An example study of the response of pine radial growth to climate variations in the forest-steppe zone shows an increase in the sensitivity of stands due to climate warming. Conclusions. Dendroclimatology is an interdisciplinary science that helps to determine how similar or not climate is today to the past and continues to play an extremely important role in the study of the response of forest ecosystems to climate change.

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