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4. Detecting and quantifying palaeoseasonality in stalagmites using geochemical and modelling approaches

Author

Baldini, James U. L., Lechleitner, Franziska A., Breitenbach, Sebastian F. M., van Hunen, Jeroen, Baldini, Lisa M., Wynn, Peter M., Jamieson, Robert A., Ridley, Harriet E., Baker, Alex J., Walczak, Izabela W., and Fohlmeister, Jens

Subjects
Physics - Geophysics
Abstract

Stalagmites are an extraordinarily powerful resource for the reconstruction of climatological palaeoseasonality. Here, we provide a comprehensive review of different types of seasonality preserved by stalagmites and methods for extracting this information. A new drip classification scheme is introduced, which facilitates the identification of stalagmites fed by seasonally responsive drips and which highlights the wide variability in drip types feeding stalagmites. This hydrological variability, combined with seasonality in Earth atmospheric processes, meteoric precipitation, biological processes within the soil, and cave atmosphere composition means that every stalagmite retains a different and distinct (but correct) record of environmental conditions. Replication of a record is extremely useful but should not be expected unless comparing stalagmites affected by the same processes in the same proportion. A short overview of common microanalytical techniques is presented, and suggested best practice discussed. In addition to geochemical methods, a new modelling technique for extracting meteoric precipitation and temperature palaeoseasonality from stalagmite d18O data is discussed and tested with both synthetic and real-world datasets. Finally, world maps of temperature, meteoric precipitation amount, and meteoric precipitation oxygen isotope ratio seasonality are presented and discussed, with an aim of helping to identify regions most sensitive to shifts in seasonality.

Published
2021
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7. Drought-Induced Civil Conflict Among the Ancient Maya

Author

Kennett, Douglas J., Masson, Marilyn, Lope, Carlos Peraza, Serafin, Stanley, George, Richard J., Spencer, Tom C., Hoggarth, Julie A., Culleton, Brendan J., Harper, Thomas K., Prufer, Keith M., Milbrath, Susan, Russell, Bradley W., González, Eunice Uc, McCool, Weston C., Aquino, Valorie V., Paris, Elizabeth H., Curtis, Jason H., Marwan, Norbert, Zhang, Mingua, Asmerom, Yemane, Polyak, Victor J., Carolin, Stacy A., James, Daniel H., Mason, Andrew J., Henderson, Gideon M., Brenner, Mark, Baldini, James U. L., Breitenbach, Sebastian F. M., and Hodell, David A.

Published
2022
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10. Seasonality of westerly moisture transport in the East Asian summer monsoon and its implications for interpreting precipitation δ18O

Author

Baker, Alexander J, Sodemann, Harald, Baldini, James UL, Breitenbach, Sebastian FM, Johnson, Kathleen R, Hunen, Jeroen, and Zhang, Pingzhong

Subjects
Climate Action, Asian monsoon, moisture sources, oxygen isotopes, rainfall, Lagrangian analysis, Atmospheric Sciences, Physical Geography and Environmental Geoscience
Abstract

East Asian summer monsoon (EASM) rainfall impacts the world’s most populous regions. Accurate EASM rainfall prediction necessitates robust paleoclimate reconstructions from proxy data and quantitative linkage to modern climatic conditions. Many precisely dated oxygen isotope records from Chinese stalagmites have been interpreted as directly reflecting past EASM rainfall amount variability, but recent research suggests that such records instead integrate multiple hydroclimatic processes. Using a Lagrangian precipitation moisture source diagnostic, we demonstrate that EASM rainfall is primarily derived from the Indian Ocean. Conversely, Pacific Ocean moisture export peaks during winter, and the moisture uptake area does not differ significantly between summer and winter and is thus a minor contributor to monsoonal precipitation. Our results are substantiated by an accurate reproduction of summer and winter spatial rainfall distributions across China. We also correlate modern EASM rainfall oxygen isotope ratios with instrumental rainfall amount and our moisture source data. This analysis reveals that the strength of the source effect is geographically variable, and differences in atmospheric moisture transport may significantly impact the isotopic signature of EASM rainfall at the Hulu, Dongge, and Wanxiang Cave sites. These results improve our ability to isolate the rainfall amount signal in paleomonsoon reconstructions and indicate that precipitation across central and eastern China will directly respond to variability in Indian Ocean moisture supply.

Published
2015

13. Spatio-temporal dynamics of speleothem growth and glaciation in the British Isles.

Author

Panitz, Sina, Rogerson, Michael, Longman, Jack, Scroxton, Nick, Lawson, Tim J., Atkinson, Tim C., Ersek, Vasile, Baldini, James, Baldini, Lisa, Umbo, Stuart, Lone, Mahjoor A., Henderson, Gideon M., and Breitenbach, Sebastian F. M.

Abstract

Reconstructing the spatio-temporal dynamics of glaciations and permafrost largely relies on surface deposits, and is therefore a challenge for every glacial older than the last due to erosion. Consequently, glaciations and permafrost remain poorly constrained worldwide before c. 30 ka. Since speleothems (carbonate cave deposits) form from drip water and generally indicate the absence of an ice sheet and permafrost, we evaluate how speleothem growth phases defined by U-series dates align with past glacial-interglacial cycles. Further, we make the first systematic comparison of the spatial distribution of speleothem dates with independent reconstructions of the history of the British-Irish Ice Sheet (BIIS) to test how well geomorphologic ice reconstructions are replicated in the cave record. The frequency distribution of 1,020 U-series dates based on three different dating methods between 300 and 5 ka shows statistically significant periods of speleothem growth during the last interglacial and several interstadials during the last glacial. A pronounced decline in speleothem growth coincides with the Last Glacial Maximum, before broad reactivation during deglaciation and into the Holocene. Spatio-temporal patterns in speleothem growth between 31 and 15 ka agree well with the surface-deposit-based reconstruction of the last BIIS. In data-rich regions, such as northern England, ice dynamics are well-replicated in the cave record, which provide additional evidence about the spatio-temporal distribution of permafrost dynamics. Beyond the Last Glacial Maximum, the distribution of speleothem dates across the British Isles offers the opportunity to improve chronological constraints on past ice sheet variability, with evidence for a highly dynamic Scottish ice sheet during the last glacial. The results provide independent evidence of ice distribution complementary to studies of surface geomorphology and geology, and the potential to extend reconstructions into permafrost and earlier glacial cycles. Whilst undersampling is currently the main limitation for speleothem-based ice and permafrost reconstruction even in relatively well-sampled parts of the British Isles, we show that speleothem dates obtained using modern mass spectrometry techniques reveal a higher spatio-temporal resolution of glacial-interglacial cycles and glacial extent than previously possible. Further study of leads and lags in speleothem growth compared to surface deposition may provide new insights into landscape-scale dynamics during ice sheet growth and retreat. [ABSTRACT FROM AUTHOR]

Published
2024
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31. Corrigendum to “The trace-element composition of a Polish stalagmite: Implications for the use of speleothems as a record of explosive volcanism” [Chemical Geology 540 (2021) 120157]

Author

Paine, Alice R., Baldini, James U.L., Wadsworth, Fabian B., Lechleitner, Franziska A., Jamieson, Robert A., Baldini, Lisa M., Brown, Richard J., Müller, Wolfgang, Hercman, Helena, Gąsiorowski, Michał, Stefaniak, Krzysztof, Socha, Paweł, Sobczyk, Artur, and Kasprzak, Marek

Published
2021
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32. Evaluating model outputs using integrated global speleothem records of climate change since the last glacial

Author

Comas-Bru, Laia, Harrison, Sandy P., Werner, Martin, Rehfeld, Kira, Scroxton, Nick, Veiga-Pires, Cristina, Ahmad, Syed Masood, Brahim, Yassine Ait, Mozhdehi, Sahar Amirnezhad, Arienzo, Monica, Atsawawaranunt, Kamolphat, Baker, Andy, Braun, Kerstin, Breitenbach, Sebastian, Burstyn, Yuval, Chawchai, Sakonvan, Columbu, Andrea, Deininger, Michael, Demeny, Attila, Dixon, Bronwyn, Hatvani, Istvan Gabor, Hu, Jun, Kaushal, Nikita, Kern, Zoltan, Labuhn, Inga, Lachniet, Matthew S., Lechleitner, Franziska A., Lorrey, Andrew, Markowska, Monika, Nehme, Carole, Novello, Valdir F., Oster, Jessica, Perez-Mejias, Carlos, Pickering, Robyn, Sekhon, Natasha, Wang, Xianfeng, Warken, Sophie, Atkinson, Tim, Ayalon, Avner, Baldini, James, Bar-Matthews, Miryam, Bernal, Juan Pablo, Boch, Ronny, Borsato, Andrea, Boyd, Meighan, Brierley, Chris, Cai, Yanjun, Carolin, Stacy, Cheng, Hai, Constantin, Silviu, Couchoud, Isabelle, Cruz, Francisco, Denniston, Rhawn, Dragusin, Virgil, Duan, Wuhui, Ersek, Vasile, Finné, Martin, Fleitmann, Dominik, Fohlmeister, Jens, Frappier, Amy, Genty, Dominique, Holzkamper, Steffen, Hopley, Philip, Johnston, Vanessa, Kathayat, Gayatri, Keenan-Jones, Duncan, Koltai, Gabriella, Li, Ting-Yong, Lone, Mahjoor Ahmad, Luetscher, Marc, Mattey, Dave, Moreno, Ana, Moseley, Gina, Psomiadis, David, Ruan, Jiaoyang, Scholz, Denis, Sha, Lijuan, Smith, Andrew Christopher, Strikis, Nicolas, Treble, Pauline, Unal-Imer, Ezgi, Vaks, Anton, Vansteenberge, Stef, Voarintsoa, Ny Riavo G., Wong, Corinne, Wortham, Barbara, Wurtzel, Jennifer, Zhang, Haiwei, Voarintsoa, Ny Riavo, Earth Observatory of Singapore, Comas-Bru L., Harrison S.P., Werner M., Rehfeld K., Scroxton N., Veiga-Pires C., Ahmad S.M., Brahim Y.A., Mozhdehi S.A., Arienzo M., Atsawawaranunt K., Baker A., Braun K., Breitenbach S., Burstyn Y., Chawchai S., Columbu A., Deininger M., Demeny A., Dixon B., Hatvani I.G., Hu J., Kaushal N., Kern Z., Labuhn I., Lachniet M.S., Lechleitner F.A., Lorrey A., Markowska M., Nehme C., Novello V.F., Oster J., Perez-Mejias C., Pickering R., Sekhon N., Wang X., Warken S., Atkinson T., Ayalon A., Baldini J., Bar-Matthews M., Bernal J.P., Boch R., Borsato A., Boyd M., Brierley C., Cai Y., Carolin S., Cheng H., Constantin S., Couchoud I., Cruz F., Denniston R., Dragusin V., Duan W., Ersek V., Finne M., Fleitmann D., Fohlmeister J., Frappier A., Genty D., Holzkamper S., Hopley P., Johnston V., Kathayat G., Keenan-Jones D., Koltai G., Li T.-Y., Lone M.A., Luetscher M., Mattey D., Moreno A., Moseley G., Psomiadis D., Ruan J., Scholz D., Sha L., Smith A.C., Strikis N., Treble P., Unal-Imer E., Vaks A., Vansteenberge S., Voarintsoa N.R.G., Wong C., Wortham B., Wurtzel J., and Zhang H.

Subjects
010506 paleontology, Climate Research, 010504 meteorology & atmospheric sciences, δ18O, lcsh:Environmental protection, Climate Change, Stratigraphy, Speleothem, Climate change, F800, PMIP4 CONTRIBUTION, Geology [Science], 01 natural sciences, Klimatforskning, STABLE-ISOTOPE VARIATIONS, lcsh:Environmental pollution, Time windows, ddc:550, Meteorology & Atmospheric Sciences, lcsh:TD169-171.8, Speleothem Records, GENERAL-CIRCULATION MODEL, ASIAN MONSOON, Glacial period, Geosciences, Multidisciplinary, DELTA-O-18 WATER ISOTOPE, Baseline (configuration management), lcsh:Environmental sciences, 0105 earth and related environmental sciences, lcsh:GE1-350, Global and Planetary Change, geography, Coupled model intercomparison project, Science & Technology, geography.geographical_feature_category, Paleontology, Geology, GROWTH FREQUENCY VARIATIONS, NORTH-ATLANTIC, OXYGEN-ISOTOPE, 13. Climate action, Climatology, lcsh:TD172-193.5, Physical Sciences, Spatial ecology, Environmental science, Institut für Geowissenschaften, ATMOSPHERIC CIRCULATION, HIGH-RESOLUTION
Abstract

Although quantitative isotope data from speleothems has been used to evaluate isotope-enabled model simulations, currently no consensus exists regarding the most appropriate methodology through which to achieve this. A number of modelling groups will be running isotope-enabled palaeoclimate simulations in the framework of the Coupled Model Intercomparison Project Phase 6, so it is timely to evaluate different approaches to using the speleothem data for data-model comparisons. Here, we illustrate this using 456 globally distributed speleothem delta O-18 records from an updated version of the Speleothem Isotopes Synthesis and Analysis (SISAL) database and palaeoclimate simulations generated using the ECHAM5-wiso isotope-enabled atmospheric circulation model. We show that the SISAL records reproduce the first-order spatial patterns of isotopic variability in the modern day, strongly supporting the application of this dataset for evaluating model-derived isotope variability into the past. However, the discontinuous nature of many speleothem records complicates the process of procuring large numbers of records if data-model comparisons are made using the traditional approach of comparing anomalies between a control period and a given palaeoclimate experiment. To circumvent this issue, we illustrate techniques through which the absolute isotope values during any time period could be used for model evaluation. Specifically, we show that speleothem isotope records allow an assessment of a model's ability to simulate spatial isotopic trends. Our analyses provide a protocol for using speleothem isotope data for model evaluation, including screening the observations to take into account the impact of speleothem mineralogy on delta O-18 values, the optimum period for the modern observational baseline and the selection of an appropriate time window for creating means of the isotope data for palaeo-time-slices. European Geosciences Union - W2017/413; Irish Centre for Research in Applied Geosciences (iCRAG); European Association of Geochemistry (Early Career Ambassadors program 2017); Quaternary Research Association UK; Navarino Environmental Observatory, Stockholm University; University College Dublin, Savillex (UK) - SF1428; Ibn Zohr University, Morocco; University of Reading; European Research Council - 694481; Natural Environment Research Council (JPI-Belmont project "PAleao-Constraints on Monsoon Evolution and Dynamics (PACMEDY)"); Geological Survey Ireland - 2017-SC-056; Royal Irish Academy; Deutsche Forschungsgemeinschaft - RE3994/2-1; Past Global Changes (PAGES) programme; info:eu-repo/semantics/publishedVersion

Published
2019
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34. Letters

Author

Rotkovitch, Rachel, Scicchitano, Theresa M., Bummara, Janet Laird, Pfister, Shirley, Bouffard, Barbara A., Ammon, Kathleen B., Syzdak, Nancy J., Macewicz, Cathy, Thomas, Ruth, Holman, Diane R., Pessar, Arlene, Meehan, Vivian, Emmerich, Kim, Kelderhouse, Susan, James, Judith K., Uustal, Diane B., Brown, Sherry, Rushton, Patricia, George, Dora L., Anderson, Sandi, Wieta, Francine, Dobbins, Anne M., and Baldini, James T.

Published
1979
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39. Detecting and quantifying palaeoseasonality in stalagmites using geochemical and modelling approaches

Author

Baldini, James U.L., primary, Lechleitner, Franziska A., additional, Breitenbach, Sebastian F.M., additional, van Hunen, Jeroen, additional, Baldini, Lisa M., additional, Wynn, Peter M., additional, Jamieson, Robert A., additional, Ridley, Harriet E., additional, Baker, Alexander J., additional, Walczak, Izabela W., additional, and Fohlmeister, Jens, additional

Published
2021
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40. Structure of the 8200-year cold event revealed by a speleothem trace element record. (Reports)

Author

Baldini, James U.L., McDermott, Frank, and Fairchild, Ian J.

Subjects
Paleoclimatology -- Research, Paleogeography -- Holocene, Science and technology, Research
Abstract

Abrupt first-order shifts in strontium and phosphorus concentrations in stalagmite calcite deposited in western Ireland during the 8200-year event (the major cooling episode 8200 years before the present) are interpreted as responses to a drier climate lasting about 37 years. Both shifts are centered on 8330 ± 80 years before the present, coinciding with a large oxygen isotope anomaly and a change in the calcite petrography. In this very high resolution (monthly) record, antipathetic second-order oscillations in phosphorus and strontium reveal decreased growth rates and increased rainfall seasonality. Growth rate variations within the event reveal a two-pronged structure consistent with recent model simulations., The 8200-year event is widely regarded as the strongest Holocene cooling episode, with clear expressions in Greenland (1, 2), the North Atlantic (3), Europe (4-11), North America (12-14), North Africa [...]

Published
2002

41. A 1,600 year record of paleoseasonality from the neotropics of Central America and its implications for rainfall predictability in agricultural societies

Author

Prufer, Keith, primary, Breitenbach, Sebastian, additional, Baldini, James, additional, Braun, Tobias, additional, Ray, Erin, additional, Baldini, Lisa, additional, Polyak, Victor, additional, Lechleitner, Franziska, additional, Marwan, Norbert, additional, Kennett, Douglas, additional, and Asmerom, Yemane, additional

Published
2020
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44. The SISAL database

Author

Atsawawaranunt, Kamolphat, Comas-Bru, Laia, Mozhdehi, Sahar Amirnezhad, Deininger, Michael, Harrison, Sandy P., Baker, Andy, Boyd, Meighan, Kaushal, Nikita, Ahmad, Syed Masood, Brahim, Yassine Ait, Arienzo, Monica, Bajo, Petra, Braun, Kerstin, Burstyn, Yuval, Chawchai, Sakonvan, Duan, Wuhui, Hatvani, Istvan Gabor, Hu, Jun, Kern, Zoltan, Labuhn, Inga, Lachniet, Matthew, Lechleitner, Franziska A., Lorrey, Andrew, Perez-Mejias, Carlos, Pickering, Robyn, Scroxton, Nick, Atkinson, Tim, Ayalon, Avner, Baldini, James, Bar-Matthews, Miriam, Pablo Bernal, Juan, Breitenbach, Sebastian, Boch, Ronny, Borsato, Andrea, Cai, Yanjun, Carolin, Stacy, Cheng, Hai, Columbu, Andrea, Couchoud, Isabelle, Cruz, Francisco, Demeny, Attila, Dominguez-Villar, David, Dragusin, Virgil, Drysdale, Russell, Ersek, Vasile, Finne, Martin, Fleitmann, Dominik, Fohlmeister, Jens Bernd (Dr.), Frappier, Amy, Genty, Dominique, Holzkamper, Steffen, Hopley, Philip, Kathayat, Gayatri, Keenan-Jones, Duncan, Koltai, Gabriella, Luetscher, Marc, Li, Ting-Yong, Lone, Mahjoor Ahmad, Markowska, Monika, Mattey, Dave, McDermott, Frank, Moreno, Ana, Moseley, Gina, Nehme, Carole, Novello, Valdir F., Psomiadis, David, Rehfeld, Kira, Ruan, Jiaoyang, Sekhon, Natasha, Sha, Lijuan, Sholz, Denis, Shopov, Yavor, Smith, Andrew, Strikis, Nicolas, Treble, Pauline, Unal-Imer, Ezgi, Vaks, Anton, Vansteenberge, Stef, Veiga-Pires, Cristina, Voarintsoa, Ny Riavo, Wang, Xianfeng, Wong, Corinne, Wortham, Barbara, Wurtzel, Jennifer, and Zong, Baoyun

Subjects
ddc:550, Institut für Geowissenschaften
Abstract

Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide "out-of-sample" evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Synthesis and Analysis) is an international working group of the Past Global Changes (PAGES) project. The working group aims to provide a comprehensive compilation of speleothem isotope records for climate reconstruction and model evaluation. The SISAL database contains data for individual speleothems, grouped by cave system. Stable isotopes of oxygen and carbon (delta O-18, delta C-13) measurements are referenced by distance from the top or bottom of the speleothem. Additional tables provide information on dating, including information on the dates used to construct the original age model and sufficient information to assess the quality of each data set and to erect a standardized chronology across different speleothems. The metadata table provides location information, information on the full range of measurements carried out on each speleothem and information on the cave system that is relevant to the interpretation of the records, as well as citations for both publications and archived data.

Published
2018

45. The SISAL database: a global resource to document oxygen and carbon isotope records from speleothems

Author

Atsawawaranunt, Kamolphat, Comas-Bru, Laia, Amirnezhad Mozhdehi, Sahar, Deininger, Michael, Harrison, Sandy P., Baker, Andy, Boyd, Meighan, Kaushal, Nikita, Ahmad, Syed Masood, Ait Brahim, Yassine, Arienzo, Monica, Bajo, Petra, Braun, Kerstin, Burstyn, Yuval, Chawchai, Sakonvan, Duan, Wuhui, Hatvani, István Gábor, Hu, Jun, Kern, Zoltán, Labuhn, Inga, Lachniet, Matthew, Lechleitner, Franziska A., Lorrey, Andrew, Pérez-Mejías, Carlos, Pickering, Robyn, Scroxton, Nick, Atkinson, Tim, Ayalon, Avner, Baldini, James, Bar-Matthews, Miriam, Bernal, Juan Pablo, Breitenbach, Sebastian, Boch, Ronny, Borsato, Andrea, Cai, Yanjun, Carolin, Stacy, Cheng, Hai, Columbu, Andrea, Couchoud, Isabelle, Cruz, Francisco, Demény, Attila, Domínguez-Villar, David, Drăgusin, Virgil, Drysdale, Russell, Ersek, Vasile, Finné, Martin, Fleitmann, Dominik, Fohlmeister, Jens, Frappier, Amy, Genty, Dominique, Holzkämper, Steffen, Kathayat, Gayatri, Keenan-Jones, Duncan, Koltai, Gabriella, Luetscher, Marc, Li, Ting-Yong, Lone, Mahjoor Ahmad, Markowska, Monika, Mattey, Dave, McDermott, Frank, Moreno, Ana, Moseley, Gina, Nehme, Carole, Novello, Valdir F., Psomiadis, David, Rehfeld, Kirah, Ruan, Jiaoyang, Sekhon, Natasha, Sha, Lijuan, Scholz, Denis, Shopov, Yavor, Strikis, Nicolás, Treble, Pauline, Ünal-İmer, Ezgi, Vaks, Anton, Vansteenberge, Stef, Veiga-Pires, Cristina, Voarintsoa, Ny Riavo, Wang, Xianfeng, Wong, Corinne, Wortham, Barbara, Wurtzel, Jennifer, and Zong, Baoyun

Abstract

Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide “out-of-sample” evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Synthesis and Analysis) is an international working group of the Past Global Changes (PAGES) project. The working group aims to provide a comprehensive compilation of speleothem isotope records for climate reconstruction and model evaluation. The SISAL database contains data for individual speleothems, grouped by cave system. Stable isotopes of oxygen and carbon (δ18O, δ13C) measurements are referenced by distance from the top or bottom of the speleothem. Additional tables provide information on dating, including information on the dates used to construct the original age model and sufficient information to assess the quality of each data set and to erect a standardized chronology across different speleothems. The metadata table provides location information, information on the full range of measurements carried out on each speleothem and information on the cave system that is relevant to the interpretation of the records, as well as citations for both publications and archived data. The compiled data are available at http://dx.doi.org/10.17864/1947.147 .

Published
2018

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