Modeling historical long-term trends of sulfate, ammonium, and elemental carbon over Europe: A comparison with ice core records in the Alps

10 Be is produced in a similar way as 14 C by the interaction of cosmic radiation with the nuclei in the atmosphere. Assuming that the 10 Be and 14 C variation are proportional and considering the different behaviour in the Earth system, the 10 Be concentrations in ice cores can be compared with the 14 C variations in tree rings. A high correlation is found for the short-term variations ( 14 C-Suess-wiggles). They reflect with a high probability production rate variations. More problematic is the interpretation of the long-term trends of 14 C and 10 Be. Several explanations are discussed. The reconstructed CO 2 concentrations in ice cores indicate a rather constant value (280 ± 10 p.p.m. by volume) during the past few millenia. Measurements on the ice core from Byrd Station, Antarctica, during the period 9000 to 6000 years BP indicate a decrease that might be explained by the extraction of CO 2 from the atmosphere-ocean system to build the terrestrial biomass pool during the climatic optimum.

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Greenland precipitation trends in a long-term instrumental climate context (1890-2012): evaluation of coastal and ice core records

International Journal of Climatology ◽

10.1002/joc.3986 ◽

2014 ◽

Vol 35 (2) ◽

pp. 303-320 ◽

Cited By ~ 54

Author(s):

Sebastian H. Mernild ◽

Edward Hanna ◽

Joseph R. McConnell ◽

Michael Sigl ◽

Andrew P. Beckerman ◽

...

Keyword(s):

Ice Core ◽

Precipitation Trends ◽

Ice Core Records

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Differing pre-industrial cooling trends between tree rings and lower-resolution temperature proxies

Climate of the Past ◽

10.5194/cp-16-729-2020 ◽

2020 ◽

Vol 16 (2) ◽

pp. 729-742 ◽

Cited By ~ 1

Author(s):

Lara Klippel ◽

Scott St. George ◽

Ulf Büntgen ◽

Paul J. Krusic ◽

Jan Esper

Keyword(s):

Tree Ring ◽

Tree Rings ◽

Ice Core ◽

Temperature Sensitive ◽

Global Trends ◽

Temperature Changes ◽

Long Term Trends ◽

Sediment Data ◽

Common Era

Abstract. The new PAGES2k global compilation of temperature-sensitive proxies offers an unprecedented opportunity to study regional to global trends associated with orbitally driven changes in solar irradiance over the past 2 millennia. Here, we analyze pre-industrial long-term trends from 1 to 1800 CE across the PAGES2k dataset and find that, in contrast to the gradual cooling apparent in ice core, marine, and lake sediment data, tree rings do not exhibit the same decline. To understand why tree-ring proxies lack any evidence of a significant pre-industrial cooling, we divide those data by location (high Northern Hemisphere latitudes vs. midlatitudes), seasonal response (annual vs. summer), detrending method, and temperature sensitivity (high vs. low). We conclude that the ability of tree-ring proxies to detect pre-industrial, millennial-long cooling is not affected by latitude, seasonal sensitivity, or detrending method. Caution is advised when using multi-proxy approaches to reconstruct long-term temperature changes over the entire Common Era.

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Holocene Climate Variability in Antarctica Based on 11 Ice-Core Isotopic Records

Quaternary Research ◽

10.1006/qres.2000.2172 ◽

2000 ◽

Vol 54 (3) ◽

pp. 348-358 ◽

Cited By ~ 239

Author(s):

Valérie Masson ◽

Françoise Vimeux ◽

Jean Jouzel ◽

Vin Morgan ◽

Marc Delmotte ◽

...

Keyword(s):

Time Trend ◽

Ross Sea ◽

Ice Core ◽

Ice Cores ◽

West Antarctica ◽

Climatic Fluctuations ◽

Long Time ◽

Long Term Trends ◽

Isotopic Records

A comparison is made of the Holocene records obtained from water isotope measurements along 11 ice cores from coastal and central sites in east Antarctica (Vostok, Dome B, Plateau Remote, Komsomolskaia, Dome C, Taylor Dome, Dominion Range, D47, KM105, and Law Dome) and west Antarctica (Byrd), with temporal resolution from 20 to 50 yr. The long-term trends possibly reflect local ice sheet elevation fluctuations superimposed on common climatic fluctuations. All the records confirm the widespread Antarctic early Holocene optimum between 11,500 and 9000 yr; in the Ross Sea sector, a secondary optimum is identified between 7000 and 5000 yr, whereas all eastern Antarctic sites show a late optimum between 6000 and 3000 yr. Superimposed on the long time trend, all the records exhibit 9 aperiodic millennial-scale oscillations. Climatic optima show a reduced pacing between warm events (typically 800 yr), whereas cooler periods are associated with less-frequent warm events (pacing >1200 yr).

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Links between MIS 11 millennial to sub-millennial climate variability and long term trends as revealed by new high resolution EPICA Dome C deuterium data – A comparison with the Holocene

Climate of the Past ◽

10.5194/cp-7-437-2011 ◽

2011 ◽

Vol 7 (2) ◽

pp. 437-450 ◽

Cited By ~ 23

Author(s):

K. Pol ◽

M. Debret ◽

V. Masson-Delmotte ◽

E. Capron ◽

O. Cattani ◽

...

Keyword(s):

High Resolution ◽

Ice Core ◽

Interglacial Period ◽

Marine Isotopic Stage ◽

The Holocene ◽

Sensitivity Tests ◽

Cooling Phase ◽

Long Term Trends ◽

The Antarctic

Abstract. We expand here the description of the Antarctic temperature variability during the long interglacial period occurring ~400 thousand years before the present (Marine Isotopic Stage, MIS 11). Our study is based on new detailed deuterium measurements conducted on the EPICA Dome C ice core, Antarctica, with a ~50 year temporal resolution. Despite an ice diffusion of a length reaching ~8 cm at MIS 11 depth, the data allow us to highlight a variability at multi-centennial scale for MIS 11, as it has already been observed for the Holocene period (MIS 1). The differences between MIS 1 and MIS 11 are analysed regarding the links between multi-millennial trends and sub-millennial variability. The EPICA Dome C deuterium record shows an increased variability and the onset of millennial to sub-millennial periodicities at the beginning of the final cooling phase of MIS 11. Our findings are robust with respect to sensitivity tests on the somewhat uncertain MIS 11 duration.

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Volcanic stratospheric sulphur injections and aerosol optical depth from 500 BCE to 1900 CE

10.5194/essd-2017-31 ◽

2017 ◽

Cited By ~ 1

Author(s):

Matthew Toohey ◽

Michael Sigl

Keyword(s):

20Th Century ◽

Aerosol Optical Depth ◽

Optical Depth ◽

Ice Core ◽

Ice Cores ◽

Volcanic Eruptions ◽

Volcanic Forcing ◽

Global Mean ◽

Ice Core Records

Abstract. The injection of sulphur into the stratosphere by explosive volcanic eruptions is the cause of significant climate variability. Based on sulphate records from a suite of ice cores from Greenland and Antarctica, the eVolv2k database includes estimates of the magnitudes and approximate source latitudes of major volcanic stratospheric sulphur injection (VSSI) events from 500 BCE to 1900 CE, constituting an update of prior reconstructions and an extension of the record by 1000 years. The VSSI estimates incorporate improvements to the ice core records in terms of synchronization and dating, refinements to the methods used to estimate VSSI from ice core records, and includes first estimates of the random uncertainties in VSSI values. VSSI estimates for many of the largest eruptions, including Samalas (1257), Tambora (1815) and Laki (1783) are within 10% of prior estimates. A number of strong events are included in eVolv2k which are largely underestimated or not included in earlier VSSI reconstructions, including events in 540, 574, 682 and 1108 CE. The long term annual mean VSSI from major volcanic eruptions is estimated to be ∼ 0.5 Tg [S] yr−1, ∼ 50 % greater than a prior reconstruction, due to the identification of more events and an increase in the magnitude of many intermediate events. A long-term, latitudinally and monthly resolved stratospheric aerosol optical depth (SAOD) time series is reconstructed from the eVolv2k VSSI estimates, and the resulting global mean SAOD is found to be similar (within 33%) to a prior reconstruction for most of the largest eruptions. The long-term (500 BCE–900 CE) average global mean SAOD estimated from the eVolv2k VSSI estimates and including a constant "background" injection of stratospheric sulphur is ∼ 0.014, 30 % greater than a prior reconstruction. These new long-term reconstructions of past VSSI and SAOD variability give context to recent volcanic forcing, suggesting that the 20th century was a period of somewhat weaker than average volcanic forcing, with current best estimates of 20th century mean VSSI and SAOD values being 25 and 14 % less, respectively, than the mean of the 500 BCE to 1900 CE period. The reconstructed VSSI and SAOD data are available at https://doi.org/10.1594/WDCC/eVolv2k_v2>.

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A Northern Hemisphere Volcanic Chemistry Record (1869–1984) and Climatic Implications Using a South Greenland Ice Core

Annals of Glaciology ◽

10.3189/s0260305500008521 ◽

1990 ◽

Vol 14 ◽

pp. 176-182 ◽

Cited By ~ 6

Author(s):

W.B. Lyons ◽

P.A. Mayewski ◽

M.J. Spencer ◽

M.S. Twickler ◽

T.E. Graedel

Keyword(s):

Global Climate ◽

Regional Climate ◽

Ice Core ◽

Volcanic Eruptions ◽

Chemical Signatures ◽

Time Period ◽

Tree Ring Data ◽

Long Term Trends ◽

Major Chemical

The effect of volcanic emission of acidic aerosols on climate is well documented. The presence of acid droplets in the stratosphere can reduce transmissivity and hence decrease surface temperatures. Since the amount and chemical composition of erupted material has important effects on regional climate, knowledge of past volcanic events is of extreme importance. Detailed glaciochemical records provide the only milieu wherein the geochemistry of paleovolcanic events can be fully documented. We present a detailed sulfate and chloride record from an ice core drilled at site 20 D, 40 km SW of Dye 3 in southern Greenland. The record spans the time period 1869–1984 with chemical analyses of approximately eight samples per year. Time series decomposition and locally weighted scatter plot smoothing techniques were used to extract long term trends from the data so that individual volcanic eruptions could be documented. A number of events identified here have been unnoticed previously and a high percentage of the major chemical signatures documenting these events is associated with large decreases in temperature in the latitudinal zone 60–90 °N. Many authors have pointed out that the amount of volcanic acids such as HCl and H2SO4 injected into the atmosphere has a very important influence on global climate, yet this volcanic input has been difficult to quantify prior to ∼1960. Our data help to alleviate this problem. These individual events can be compared to available frost tree ring data from North America, further establishing a volcanism-climatic linkage.

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