Persistent draining of the stratospheric 10Be reservoir after the Samalas volcanic eruption (1257 CE)

More than 2,000 analyses of beryllium&#8208;10 (10Be) and sulphate concentrations were performed at a nominal subannual resolution on an ice core covering the last millennium as well as on shorter records from three sites in Antarctica (Dome C, South Pole, and Vostok) to better understand the increase in 10Be deposition during stratospheric volcanic eruptions.A significant increase in 10Be concentration is observed in 14 of the 26 volcanic events studied. The slope and intercept of the linear regression between 10Be and sulphate concentrations provide different and complementary information. Slope is an indicator of the efficiency of the draining of 10Be atoms by volcanic aerosols depending on the amount of sulphur dioxide (SO2) released and on the altitude it reaches in the stratosphere. The intercept provides an appreciation of the 10Be production in the stratospheric reservoir, ultimately depending on solar modulation (Baroni et al., 2019, JGR).Among all the identified events, the Samalas event (1257 CE) stands out as the biggest eruption of the last millennium with the lowest positive slope. It released (158 &#177; 12) Tg of SO2 up to an altitude of 43 km in the stratosphere (Lavigne et al., 2013, PNAS ; Vidal et al., 2016, Sci. Rep.). We hypothesize that the persistence of volcanic aerosols in the stratosphere after the Samalas eruption has drained the stratospheric 10Be reservoir for a decade.The persistence of Samalas sulphate aerosols might be due to the increase of SO2 lifetime because of: (i) the exhaustion of the OH reservoir required for sulphate formation (e.g. (Bekki, 1995, GRL; Bekki et al., 1996, GRL; Savarino et al., 2003, JGR); and/or, (ii) the evaporation followed by photolysis of gaseous sulphuric acid back to SO2 at altitudes higher than 30 km (Delaygue et al., 2015, Tellus; Rinsland et al., 1995, GRL). In addition, the lifetime of air masses increases to 5 years above 30 km altitude compared with 1 year for aerosols and air masses in the lower stratosphere (Delaygue et al., 2015, Tellus). When this high-altitude SO2 finally returns below the 30 km limit, it could be oxidized back to sulphate and forms new sulphate aerosols. These processes could imply that the 10Be reservoir is washed out over a long time period following the end of the eruption of Samalas.This would run counter to modelling studies that predict the formation of large particle sizes and their rapid fall out due to the large amount of SO2, which would limit the climatic impact of Samalas-type eruptions (Pinto et al., 1989, JGR; Timmreck et al., 2010, 2009, GRL).

Download Full-text

Antarctic Anion Glaciochemistry (Abstract only)

Annals of Glaciology ◽

10.1017/s0260305500003311 ◽

1982 ◽

Vol 3 ◽

pp. 354

Author(s):

Michael M. Herron

Keyword(s):

Fossil Fuel ◽

Accumulation Rate ◽

Ice Core ◽

Volcanic Eruptions ◽

Snow Accumulation ◽

Scale Height ◽

Solar Modulation ◽

Fossil Fuel Combustion ◽

Marine Aerosol ◽

Major Anions

Snow and ice-core samples from a number of sites in Antarctica and Greenland have been analyzed for the major anions Cl−, NO3 −, and SO4 2- by ion chromatography. Reproducibility on adjacent core or pit samples is ±10% at the 95% confidence level. Chloride is of marine origin except following some major volcanic eruptions. Chloride concentrations decrease exponentially with increasing site elevation with a scale height of about 1.5 km. For sites of comparable elevation, Antarctic Cl− concentrations are only slightly higher than in Greenland. Sulfate concentrations, corrected for the marine aerosol contribution, show an inverse dependence on snow accumulation rate. For sites of comparable accumulation rate, Greenland concentrations exceed those in Antarctica by a factor of 2 to 3. Nitrate concentrations also decrease with increasing accumulation rate and for comparable sites Greenland NO3 − concentrations are a factor of 2 higher than in Antarctica. There is no evidence of solar modulation or supernova perturbation of Greenland NO3 − concentrations. The Byrd deep core is shown to have distinct seasonal variations in Cl− and SO4 2- that may be used for dating. In addition, the Byrd core contains volcanic signals similar to those found in Greenland. Recent Greenland snow contains about 4 times as much SO4 2- and 2 to 3 times as much NO3 − as is found in older ice due to modern fossil fuel combustion.

Download Full-text

Antarctic Anion Glaciochemistry (Abstract only)

Annals of Glaciology ◽

10.3189/s0260305500003311 ◽

1982 ◽

Vol 3 ◽

pp. 354-354

Author(s):

Michael M. Herron

Keyword(s):

Fossil Fuel ◽

Accumulation Rate ◽

Ice Core ◽

Volcanic Eruptions ◽

Snow Accumulation ◽

Scale Height ◽

Solar Modulation ◽

Fossil Fuel Combustion ◽

Marine Aerosol ◽

Major Anions

Snow and ice-core samples from a number of sites in Antarctica and Greenland have been analyzed for the major anions Cl−, NO3−, and SO42- by ion chromatography. Reproducibility on adjacent core or pit samples is ±10% at the 95% confidence level. Chloride is of marine origin except following some major volcanic eruptions. Chloride concentrations decrease exponentially with increasing site elevation with a scale height of about 1.5 km. For sites of comparable elevation, Antarctic Cl− concentrations are only slightly higher than in Greenland. Sulfate concentrations, corrected for the marine aerosol contribution, show an inverse dependence on snow accumulation rate. For sites of comparable accumulation rate, Greenland concentrations exceed those in Antarctica by a factor of 2 to 3. Nitrate concentrations also decrease with increasing accumulation rate and for comparable sites Greenland NO3− concentrations are a factor of 2 higher than in Antarctica. There is no evidence of solar modulation or supernova perturbation of Greenland NO3− concentrations. The Byrd deep core is shown to have distinct seasonal variations in Cl− and SO42- that may be used for dating. In addition, the Byrd core contains volcanic signals similar to those found in Greenland. Recent Greenland snow contains about 4 times as much SO42- and 2 to 3 times as much NO3− as is found in older ice due to modern fossil fuel combustion.

Download Full-text

Volcanic Fluxes Over the Last Millennium as Recorded in the Gv7 Ice Core (Northern Victoria Land, Antarctica)

Geosciences ◽

10.3390/geosciences10010038 ◽

2020 ◽

Vol 10 (1) ◽

pp. 38 ◽

Cited By ~ 3

Author(s):

Raffaello Nardin ◽

Alessandra Amore ◽

Silvia Becagli ◽

Laura Caiazzo ◽

Massimo Frezzotti ◽

...

Keyword(s):

Accumulation Rate ◽

Ice Core ◽

Ice Cores ◽

Volcanic Eruptions ◽

Deposition Flux ◽

Last Millennium ◽

Regional Variability ◽

High Accumulation ◽

Continental Scale ◽

Victoria Land

Major explosive volcanic eruptions may significantly alter the global atmosphere for about 2–3 years. During that period, volcanic products (mainly H2SO4) with high residence time, stored in the stratosphere or, for shorter times, in the troposphere are gradually deposited onto polar ice caps. Antarctic snow may thus record acidic signals providing a history of past volcanic events. The high resolution sulphate concentration profile along a 197 m long ice core drilled at GV7 (Northern Victoria land) was obtained by Ion Chromatography on around 3500 discrete samples. The relatively high accumulation rate (241 ± 13 mm we yr −1) and the 5-cm sampling resolution allowed a preliminary counted age scale. The obtained stratigraphy covers roughly the last millennium and 24 major volcanic eruptions were identified, dated, and tentatively ascribed to a source volcano. The deposition flux of volcanic sulphate was calculated for each signature and the results were compared with data from other Antarctic ice cores at regional and continental scale. Our results show that the regional variability is of the same order of magnitude as the continental one.

Download Full-text

Climatic Impact of Volcanic Eruptions

The Scientific World JOURNAL ◽

10.1100/tsw.2002.83 ◽

2002 ◽

Vol 2 ◽

pp. 869-884 ◽

Cited By ~ 3

Author(s):

Gregory A. Zielinski

Keyword(s):

Time Scales ◽

Global Climate ◽

Ice Core ◽

Volcanic Eruptions ◽

Ice Age ◽

Climatic Impact ◽

Global Cooling ◽

Temperature Records ◽

Instrumental Temperature ◽

Cool Climate

Volcanic eruptions have the potential to force global climate, provided they are explosive enough to emit at least 1–5 megaton of sulfur gases into the stratosphere. The sulfuric acid produced during oxidation of these gases will both absorb and reflect incoming solar radiation, thus warming the stratosphere and cooling the Earth’s surface. Maximum global cooling on the order of 0.2–0.3°C, using instrumental temperature records, occurs in the first 2 years after the eruption, with lesser cooling possibly up to the 4th year. Equatorial eruptions are able to affect global climate, whereas mid- to high-latitude events will impact the hemisphere of origin. However, regional responses may differ, including the possibility of winter warming following certain eruptions. Also, El Niño warming may override the cooling induced by volcanic activity. Evaluation of different style eruptions as well as of multiple eruptions closely spaced in time beyond the instrumental record is attained through the analysis of ice-core, tree-ring, and geologic records. Using these data in conjunction with climate proxy data indicates that multiple eruptions may force climate on decadal time scales, as appears to have occurred during the Little Ice Age (i.e., roughly AD 1400s–1800s). The Toba mega-eruption of ~75,000 years ago may have injected extremely large amounts of material into the stratosphere that remained aloft for up to about 7 years. This scenario could lead to the initiation of feedback mechanisms within the climate system, such as cooling of sea-surface temperatures. These interacting mechanisms following a mega-eruption may cool climate on centennial time scales.

Download Full-text

Volcanic fluxes over the last millennium as recorded in the GV7 ice core (Northern Victoria Land, Antarctica)

10.5194/egusphere-egu2020-10616 ◽

2020 ◽

Author(s):

Rita Traversi ◽

Silvia Becagli ◽

Mirko Severi ◽

Raffaello Nardin ◽

Laura Caiazzo ◽

...

Keyword(s):

Accumulation Rate ◽

Ice Core ◽

Ice Cores ◽

Volcanic Eruptions ◽

Deposition Flux ◽

Last Millennium ◽

Regional Variability ◽

High Accumulation ◽

Continental Scale ◽

Victoria Land

Explosive volcanic eruptions are able to affect significantly the atmosphere for 2&#8208;3 years. During this time, volcanic products (mainly H2SO4) with high residence &#8232;time are stored in the stratosphere/troposphere, and eventually deposited onto polar ice caps; snow layers may thus record signals providing a history of past &#8232;volcanic events. A high resolution sulphate concentration profile along a 197 m long ice core drilled at GV7 (Northern Victoria Land) was obtained by Ion Chromatography. The relatively high accumulation rate (241&#177;13 mm we yr-1) and the 5&#8208;cm resolution allowed a preliminary counted age scale. The obtained stratigraphy covers roughly the last millennium and 24 major volcanic eruptions were identified, dated and &#8232;ascribed to a source volcano. The deposition flux of volcanic sulfate was calculated and the results were compared with data from other Antarctic ice cores at regional and continental scale. Our results show that the regional variability is of the same order of magnitude &#8232;of the continental scale.

Download Full-text

Cryptotephra from the Icelandic Veiðivötn 1477 CE eruption in a Greenland ice core: confirming the dating of 1450s CE volcanic events and assessing the eruption's climatic impact

10.5194/cp-2020-104 ◽

2020 ◽

Author(s):

Peter M. Abbott ◽

Gill Plunkett ◽

Christophe Corona ◽

Nathan J. Chellman ◽

Joseph R. McConnell ◽

...

Keyword(s):

Northern Hemisphere ◽

Tree Ring ◽

Chemical Elements ◽

Climatic Variability ◽

Ice Core ◽

Ice Cores ◽

Volcanic Eruptions ◽

Ice Age ◽

Climate Projections ◽

Climatic Impact

Abstract. Volcanic eruptions are a key source of climatic variability and reconstructing their past impact can improve our understanding of the operation of the climate system and increase the accuracy of future climate projections. Two annually resolved and independently dated palaeoarchives – tree rings and polar ice cores – can be used in tandem to assess the timing, strength and climatic impact of volcanic eruptions over the past ~ 2500 years. The quantification of post-volcanic climate responses, however, has at times been hampered by differences between simulated and observed temperature responses that raised questions regarding the robustness of the chronologies of both archives. While many chronological mismatches have been resolved, the precise timing and climatic impact of one or more major sulphate emitting volcanic eruptions during the 1450s CE, including the largest atmospheric sulphate loading event in the last 700 years, has not been constrained. Here we explore this issue through a combination of tephrochronological evidence and high-resolution ice-core chemistry measurements from the TUNU2013 ice core. We identify tephra from the historically dated 1477 CE eruption of Veiðivötn-Bárðarbunga, Iceland, in direct association with a notable sulphate peak in TUNU2013 attributed to this event, confirming that it can be used as a reliable and precise time-marker. Using seasonal cycles in several chemical elements and 1477 CE as a fixed chronological point shows that ages of 1453 CE and 1458/59 CE can be attributed, with a high accuracy, to two notable sulphate peaks. This confirms the accuracy of the NS1-2011 Greenland ice-core chronology over the mid- to late 15th century and corroborate the findings of recent volcanic reconstructions from Greenland and Antarctica. Overall, this implies that large-scale Northern Hemisphere climatic cooling affecting tree-ring growth in 1453 CE was caused by a Northern Hemisphere volcanic eruption in 1452 CE and then a Southern Hemisphere eruption, previously assumed to have triggered the cooling, occurred later in 1458 CE. The direct attribution of the 1477 CE sulphate peak to the eruption of Veiðivötn, the most explosive from Iceland in the last 1200 years, also provides the opportunity to assess its climatic impact. A tree-ring based reconstruction of Northern Hemisphere summer temperatures shows a cooling of −0.35 °C in the aftermath of the eruption, the 356th coldest summer since 500 CE, a relatively weak and spatially incoherent climatic response in comparison to the less explosive but longer-lasting Icelandic Eldgjá 939 CE and Laki 1783 CE eruptions, that ranked as the 205th and 9th coldest summers respectively. In addition, the Veiðivötn 1477 CE eruption occurred around the inception of the Little Ice Age and could be used as a chronostratigraphic marker to constrain the phasing and spatial variability of climate changes over this transition if it can be traced into more regional palaeoclimatic archives.

Download Full-text

Minimum-size detection limit for volcanic glass particles using automated scanning electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100132066 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1486-1487

Author(s):

Mark S. Germani

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Ice Core ◽

Ice Cores ◽

Volcanic Glass ◽

Volcanic Eruptions ◽

Minimum Size ◽

Climatic Impact ◽

Automated Scanning ◽

Scanning Electron

Ice cores contain a detailed record of fallout from large volcanic eruptions. Identification of volcanic glass particles is used to aid in dating ice cores (tephrachronology). In addition, it should be possible to relate concentrations of volcanogenically-derived species; silicate glass particles, sulfate (from oxidation of SO2), chloride and fluoride to atmospheric levels which existed shortly after eruption. This information, coupled with proxy meteorological records from the core, can be used to assess the climatic impact from major volcanic eruptions.Automated scanning electron microscopy has been used to detect volcanic glass particles >1 μm in diameter in ice core meltwater samples filtered onto Nuclepore filters. It is important to be able to detect submicrometer volcanic glass particles because of their longer atmospheric residence time and the fact that they comprise a significant portion of the number of glass particles deposited in an ice core. Existing procedures for automated analysis of micrometer size particles need to be modified to efficiently analyze submicrometer particles.

Download Full-text

Quantifying the influence of natural forcing on oxygen isotope variability in alpine and polar ice core sites

10.5194/egusphere-egu2020-19341 ◽

2020 ◽

Author(s):

Kira Rehfeld ◽

Moritz Kirschner ◽

Max Holloway ◽

Louise Sime

Keyword(s):

Surface Temperature ◽

Oxygen Isotope ◽

Ice Core ◽

Ice Cores ◽

Volcanic Eruptions ◽

Isotope Ratios ◽

Tibet Plateau ◽

European Alps ◽

Last Millennium ◽

The Tibet Plateau

Stable water isotope ratios are routinely used to infer past climatic conditions in palaeoclimate archives. In particular, oxygen isotope ratios in precipitation co-vary with temperature in high latitudes, and have been established as indicators for past temperature changes in ice-cores. The timescales for which this holds, and the validity of spatial/temporal regression slopes are difficult to constrain based on the observational record.Here, surface climate and oxygen isotope ratio variability are compared across an ensemble of millennial-long simulations with the isotope-enabled version of the Hadley Centre Coupled Model version 3 (iHadCM3). The ensemble consists, amongst others, of paired experiments. One half were performed as conventional palaeoclimate equilibrium simulations for the Last Glacial Maximum (LGM, orbital and trace gas concentrations of 21kyrs BP), the mid Holocene (conditions 6kyrs BP) and the pre-industrial period (PI, 1850CE) analogously to the simulations in the Palaeoclimate Modeling Intercomparison Project. The second half of the ensemble is additionally perturbed by radiative forcing variations from solar variability and volcanic forcing as for the last millennium. Each simulation is continued for at least 1050 years.We find that global mean surface temperature and precipitation decrease significantly in all considered climate states (LGM, 6k, PI). Post-volcanic temperature reduction is fairly consistent across the globe, but weak in Antarctica. In the PI state, we find a significant increase in the AMOC strength after eruptions. This does not occur for the LGM state. No significant responses to solar forcing were detectable in the isotopic record. Correlating precipitation-weighted &#948;18O (&#948;18Opr) at these locations with surface temperature across the globe shows strong linear relationships and teleconnections. In Greenland, &#948;18Opr, at the decadal scale, shows high correlations across the Northern hemisphere for the PI simulations, but this spatial representativeness is smaller in the LGM.We finally examine the detectability of strong interannual volcanic impacts in the climate and isotope record at ice core drill sites in West and East Antarctica, Greenland, the European Alps and the Tibet Plateau. At all locations, modeled isotope and climate variance is higher in the naturally forced simulations. On annual time scales, we find only weak imprints of sub-supervolcanic eruptions in annual &#948;18Opr at most locations compared to interannual variability, with the exception of the Tibet plateau. We extend this epoch analysis to high-resolution ice core records to assess the consistency between modeled and measured isotope variations for prominent volcanic eruptions over the last millennium.The inclusion of natural forcing in the simulations alleviates the discrepancy between modeled and observed isotope variability. However, the gap cannot be closed completely. This suggests that improving our understanding of the signal formation process, the dynamical origins of isotope signatures, and model biases at all latitudes is important to constrain the regional to global representativeness of stable water isotopes in ice cores.

Download Full-text

Cryptotephra from the Icelandic Veiðivötn 1477 CE eruption in a Greenland ice core: confirming the dating of volcanic events in the 1450s CE and assessing the eruption's climatic impact

Climate of the Past ◽

10.5194/cp-17-565-2021 ◽

2021 ◽

Vol 17 (2) ◽

pp. 565-585

Author(s):

Peter M. Abbott ◽

Gill Plunkett ◽

Christophe Corona ◽

Nathan J. Chellman ◽

Joseph R. McConnell ◽

...

Keyword(s):

Northern Hemisphere ◽

Tree Ring ◽

Climatic Variability ◽

Ice Core ◽

Ice Cores ◽

Volcanic Eruptions ◽

Ice Age ◽

Climate Projections ◽

Climatic Impact ◽

Volcanic System

Abstract. Volcanic eruptions are a key source of climatic variability, and reconstructing their past impact can improve our understanding of the operation of the climate system and increase the accuracy of future climate projections. Two annually resolved and independently dated palaeoarchives – tree rings and polar ice cores – can be used in tandem to assess the timing, strength and climatic impact of volcanic eruptions over the past ∼ 2500 years. The quantification of post-volcanic climate responses, however, has at times been hampered by differences between simulated and observed temperature responses that raised questions regarding the robustness of the chronologies of both archives. While many chronological mismatches have been resolved, the precise timing and climatic impact of two major sulfate-emitting volcanic eruptions during the 1450s CE, including the largest atmospheric sulfate-loading event in the last 700 years, have not been constrained. Here we explore this issue through a combination of tephrochronological evidence and high-resolution ice-core chemistry measurements from a Greenland ice core, the TUNU2013 record. We identify tephra from the historically dated 1477 CE eruption of the Icelandic Veiðivötn–Bárðarbunga volcanic system in direct association with a notable sulfate peak in TUNU2013 attributed to this event, confirming that this peak can be used as a reliable and precise time marker. Using seasonal cycles in several chemical elements and 1477 CE as a fixed chronological point shows that ages of 1453 CE and 1458 CE can be attributed, with high precision, to the start of two other notable sulfate peaks. This confirms the accuracy of a recent Greenland ice-core chronology over the middle to late 15th century and corroborates the findings of recent volcanic reconstructions from Greenland and Antarctica. Overall, this implies that large-scale Northern Hemisphere climatic cooling affecting tree-ring growth in 1453 CE was caused by a Northern Hemisphere volcanic eruption in 1452 or early 1453 CE, and then a Southern Hemisphere eruption, previously assumed to have triggered the cooling, occurred later in 1457 or 1458 CE. The direct attribution of the 1477 CE sulfate peak to the eruption of Veiðivötn, one of the most explosive from Iceland in the last 1200 years, also provides the opportunity to assess the eruption's climatic impact. A tree-ring-based reconstruction of Northern Hemisphere summer temperatures shows a cooling in the aftermath of the eruption of −0.35 ∘C relative to a 1961–1990 CE reference period and −0.1 ∘C relative to the 30-year period around the event, as well as a relatively weak and spatially incoherent climatic response in comparison to the less explosive but longer-lasting Icelandic Eldgjá 939 CE and Laki 1783 CE eruptions. In addition, the Veiðivötn 1477 CE eruption occurred around the inception of the Little Ice Age and could be used as a chronostratigraphic marker to constrain the phasing and spatial variability of climate changes over this transition if it can be traced in more regional palaeoclimatic archives.

Download Full-text