1
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Gorin AL, Shakun JD, Jones AG, Kennedy TM, Marcott SA, Goehring BM, Zoet LK, Jomelli V, Bromley GRM, Mateo EI, Mark BG, Rodbell DT, Gilbert A, Caffee MW. Recent tropical Andean glacier retreat is unprecedented in the Holocene. Science 2024; 385:517-521. [PMID: 39088605 DOI: 10.1126/science.adg7546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 07/02/2024] [Indexed: 08/03/2024]
Abstract
Tropical glaciers have retreated over recent decades, but whether the magnitude of this retreat exceeds the bounds of Holocene fluctuations is unclear. We measured cosmogenic beryllium-10 and carbon-14 concentrations in recently exposed bedrock at the margin of four glaciers spanning the tropical Andes to reconstruct their past extents relative to today. Nuclide concentrations are near zero in almost all samples, suggesting that these locations were never exposed during the Holocene. Our data imply that many glaciers in the tropics are probably now smaller than they have been in at least 11,700 years, making the tropics the first large region where this milestone has been documented.
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Affiliation(s)
- Andrew L Gorin
- Department of Earth and Environmental Sciences, Boston College, Chestnut Hill, MA, USA
- Department of Earth and Planetary Science, University of California, Berkeley, Berkeley, CA, USA
| | - Jeremy D Shakun
- Department of Earth and Environmental Sciences, Boston College, Chestnut Hill, MA, USA
| | - Andrew G Jones
- Department of Geoscience, University of Wisconsin-Madison, Madison, WI, USA
| | - Tori M Kennedy
- Department of Earth and Environmental Sciences, Tulane University of Louisiana, New Orleans, LA, USA
| | - Shaun A Marcott
- Department of Geoscience, University of Wisconsin-Madison, Madison, WI, USA
| | - Brent M Goehring
- Department of Earth and Environmental Sciences, Tulane University of Louisiana, New Orleans, LA, USA
| | - Lucas K Zoet
- Department of Geoscience, University of Wisconsin-Madison, Madison, WI, USA
| | - Vincent Jomelli
- Aix-Marseille University, CNRS, IRD, Collège de France, INRAE, CEREGE, Aix-en-Provence, France
| | | | | | - Bryan G Mark
- Department of Geography and Byrd Polar and Climate Research Center, The Ohio State University, Columbus, OH, USA
| | | | - Adrien Gilbert
- Université Grenoble Alpes, CNRS, IRD, G-INP, Institut des Geosciences de l'Environnement, Grenoble, France
| | - Marc W Caffee
- Department of Physics and Astronomy and Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, IN, USA
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2
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Chen F, Wang T, Zhao X, Esper J, Ljungqvist FC, Büntgen U, Linderholm HW, Meko D, Xu H, Yue W, Wang S, Yuan Y, Zheng J, Pan W, Roig F, Hadad M, Hu M, Wei J, Chen F. Coupled Pacific Rim megadroughts contributed to the fall of the Ming Dynasty's capital in 1644 CE. Sci Bull (Beijing) 2024:S2095-9273(24)00263-9. [PMID: 38811339 DOI: 10.1016/j.scib.2024.04.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 03/25/2024] [Accepted: 03/26/2024] [Indexed: 05/31/2024]
Abstract
Historical documents provide evidence for regional droughts preceding the political turmoil and fall of Beijing in 1644 CE, when more than 20 million people died in northern China during the late Ming famine period. However, the role climate and environmental changes may have played in this pivotal event in Chinese history remains unclear. Here, we provide tree-ring evidence of persistent megadroughts from 1576 to 1593 CE and from 1624 to 1643 CE in northern China, which coincided with exceptionally cold summers just before the fall of Beijing. Our analysis reveals that these regional hydroclimatic extremes are part of a series of megadroughts along the Pacific Rim, which not only impacted the ecology and society of monsoonal northern China, but likely also exacerbated external geopolitical and economic pressures. This finding is corroborated by last millennium reanalysis data and numerical climate model simulations revealing internally driven Pacific sea surface temperature variations and the predominance of decadal scale La Niña-like conditions to be responsible for precipitation decreases over northern China, as well as extensive monsoon regions in the Americas. These teleconnection patterns provide a mechanistic explanation for reoccurring drought spells during the late Ming Dynasty and the environmental framework fostering the fall of Beijing in 1644 CE, and the subsequent demise of the Ming Dynasty.
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Affiliation(s)
- Feng Chen
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650504, China; Southwest United Graduate School, Kunming 650504, China.
| | - Tao Wang
- Climate Change Research Center and Nansen-Zhu International Research Centre, Institute of Atmospheric Physics, Chinese Academy of Sciences (CAS), Beijing 100029, China
| | - Xiaoen Zhao
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650504, China; Southwest United Graduate School, Kunming 650504, China
| | - Jan Esper
- Department of Geography, Johannes Gutenberg University, Mainz 55099, Germany; Global Change Research Institute (CzechGlobe), Czech Academy of Sciences, Brno 60300, Czech Republic
| | - Fredrik Charpentier Ljungqvist
- Department of History, Stockholm University, Stockholm 10691, Sweden; Bolin Centre for Climate Research, Stockholm University, Stockholm 10691, Sweden; Swedish Collegium for Advanced Study, Linneanum, Thunbergsvägen 2, Uppsala 75238, Sweden
| | - Ulf Büntgen
- Department of Geography, University of Cambridge, Cambridge CB2 3EN, UK; Global Change Research Institute (CzechGlobe), Czech Academy of Sciences, Brno 60300, Czech Republic; Department of Geography, Faculty of Science, Masaryk University, Brno 61137, Czech Republic; Swiss Federal Research Institute (WSL), Birmensdorf 8903, Switzerland
| | - Hans W Linderholm
- Regional Climate Group, Department of Earth Sciences, University of Gothenburg, Gothenburg 40530, Sweden
| | - David Meko
- Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ 85721, USA
| | - Hongna Xu
- Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC‑FEMD), Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Weipeng Yue
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650504, China
| | - Shijie Wang
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650504, China; Southwest United Graduate School, Kunming 650504, China
| | - Yujiang Yuan
- Key Laboratory of Tree-ring Physical and Chemical Research, Institute of Desert Meteorology, China Meteorological Administration, Urumqi 830002, China
| | - Jingyun Zheng
- Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Wei Pan
- Key Laboratory of Digital Human Technology R&D and Application of Yunnan Provincial Department of Education, Yunnan University, Kunming 650504, China
| | - Fidel Roig
- Laboratorio de Dendrocronología e Historia Ambiental, IANIGLA-CCT CONICET-Universidad Nacional de Cuyo, Mendoza 5500, Argentina; Hémera Centro de Observación de La Tierra, Escuela de Ingeniería ForestalFacultad de Ciencias, Universidad Mayor, Huechuraba 8580745, Santiago, Chile
| | - Martín Hadad
- Laboratorio de Dendrocronología de Zonas Áridas CIGEOBIO (CONICET-UNSJ), Gabinete de Geología Ambiental (INGEO-UNSJ), San Juan 3306, Argentina
| | - Mao Hu
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650504, China; Southwest United Graduate School, Kunming 650504, China
| | - Jiachang Wei
- Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security, Institute of International Rivers and Eco-Security, Yunnan University, Kunming 650504, China
| | - Fahu Chen
- ALPHA, State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research (ITPCAS), Chinese Academy of Sciences (CAS), Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China; MOE Key Laboratory of Western China's Environmental System, Lanzhou University, Lanzhou 730000, China
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3
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Geng J, Yan H, Liu C, Han T, Liu S, Zhao N, Wen H, Yang H, Zhou P, Wang G, Dodson J. Reconstruction of ENSO variability using the standardized growth index of a Tridacna shell from Yongshu Reef, South China Sea. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169118. [PMID: 38065507 DOI: 10.1016/j.scitotenv.2023.169118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 12/01/2023] [Accepted: 12/03/2023] [Indexed: 12/23/2023]
Abstract
El Niño-Southern Oscillation (ENSO) is the strongest signal of global interannual climate anomaly and reconstructing past ENSO variations using high-resolution paleoclimate archives can improve our understanding of ENSO variability, as well as improve our ability to predict future climate changes. Here, a daily resolution standardized growth index (SGI) was established using a giant clam (Tridacna spp.) shell specimen MD2 (life span: 1994-2013 CE), collected from the Yongshu Reef, southern South China Sea (SCS). The cross-spectral and correlation analysis indicated that the SGI variation of MD2 was strongly influenced by ENSO variability on an interannual timescale. Tridacna spp. is in symbiosis with zooxanthellae, and its growth index is usually modulated by the photosynthetic efficiency of zooxanthellae. During the El Niño (La Niña) period, the convective anomalies stimulated in western Pacific would increase (decrease) the effective solar radiation on Yongshu Reef, and in turn influence the photosynthesis rate of zooxanthellae and enzyme activity for the calcification site and thus the SGI of giant clam MD2. The SGI can explain 54.7 % of ENSO variance, demonstrating the potential for Tridacna SGI in ENSO reconstruction. Compared with conventional ENSO reconstruction using high-resolution geochemical proxies, the method of giant clam SGI is rapid and economical.
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Affiliation(s)
- Jun Geng
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hong Yan
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Open Studio for Oceanic-Continental Climate and Environment Changes, Laoshan Laboratory, Qingdao 266237, China; Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an 710049, China.
| | - Chengcheng Liu
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Xi'an Institute for Innovative Earth Environment Research, Xi'an 710061, China
| | - Tao Han
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Xi'an Institute for Innovative Earth Environment Research, Xi'an 710061, China
| | - Shan Liu
- Xi'an Institute for Innovative Earth Environment Research, Xi'an 710061, China
| | - Nanyu Zhao
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Hanfeng Wen
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haotian Yang
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an 710049, China
| | - Pengchao Zhou
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Guozhen Wang
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - John Dodson
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney 2052, Australia
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4
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Falster G, Konecky B, Coats S, Stevenson S. Forced changes in the Pacific Walker circulation over the past millennium. Nature 2023; 622:93-100. [PMID: 37612511 PMCID: PMC10550830 DOI: 10.1038/s41586-023-06447-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 07/14/2023] [Indexed: 08/25/2023]
Abstract
The Pacific Walker circulation (PWC) has an outsized influence on weather and climate worldwide. Yet the PWC response to external forcings is unclear1,2, with empirical data and model simulations often disagreeing on the magnitude and sign of these responses3. Most climate models predict that the PWC will ultimately weaken in response to global warming4. However, the PWC strengthened from 1992 to 2011, suggesting a significant role for anthropogenic and/or volcanic aerosol forcing5, or internal variability. Here we use a new annually resolved, multi-method, palaeoproxy-derived PWC reconstruction ensemble (1200-2000) to show that the 1992-2011 PWC strengthening is anomalous but not unprecedented in the context of the past 800 years. The 1992-2011 PWC strengthening was unlikely to have been a consequence of volcanic forcing and may therefore have resulted from anthropogenic aerosol forcing or natural variability. We find no significant industrial-era (1850-2000) PWC trend, contrasting the PWC weakening simulated by most climate models3. However, an industrial-era shift to lower-frequency variability suggests a subtle anthropogenic influence. The reconstruction also suggests that volcanic eruptions trigger El Niño-like PWC weakening, similar to the response simulated by climate models.
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Affiliation(s)
- Georgina Falster
- Australian Research Council Centre of Excellence for Climate Extremes, Canberra, Australian Capital Territory, Australia.
- Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, USA.
- Research School of Earth Sciences, Australian National University, Canberra, Australia.
| | - Bronwen Konecky
- Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | - Sloan Coats
- Department of Earth Sciences, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Samantha Stevenson
- Bren School of Environmental Science and Management, University of California, Santa Barbara, Santa Barbara, CA, USA
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5
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Climatic and Cultural Transitions in Lambayeque, Peru, 600 to 1540 AD: Medieval Warm Period to the Spanish Conquest. GEOSCIENCES 2022. [DOI: 10.3390/geosciences12060238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
The Lambayeque Valley on the north coast of Peru offers a cautionary case study on the relation between climatic and cultural change. Three archaeological site complexes dating from late in the first millennium AD to the middle of the second millennium AD rose and were abandoned in sequence. Each abandonment was associated with a conflagration on the main pyramidal mound(s). In this region, El Niño is the most significant climatic disruption now and for millennia past. By tracking proxy records for El Niño intensity, we found that only the first episode of abandonment and burning was associated with a strong peak in El Niño intensity, while the final episode was the outcome of the Spanish Conquest of the Andes, a distinctly non-climatic driver. These records suggest that equifinality is operative and urge caution in over-interpreting climate as culture-changing catastrophe.
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6
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Yang D, Yao T, Wu G, Zhu M, Zhao H, Shi Y, Qu D. Different patterns and origins between northwestern and southeastern Tibetan ice core glaciochemical records over the past century. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 819:153195. [PMID: 35051462 DOI: 10.1016/j.scitotenv.2022.153195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 06/14/2023]
Abstract
Atmospheric circulation systems differ between the northern and southern Tibetan Plateau (TP) and are characterized by prevailing westerly winds and the Indian monsoon, respectively. This leads to spatial differences between glaciochemical records in the northwestern and southeastern TP. We compared the spatial differences in major soluble ion concentrations (Ca2+, SO42-, NO3-, NH4+, Cl-, Na+, K+, and Mg2+) during the last century in the Aru (northwestern TP) and East Rongbuk (ER; southeastern TP) ice cores. Ca2+ exhibited the largest difference between the ice cores (2371 ppb in the Aru ice core and 65 ppb in the ER ice core), indicating that crustal processes were more dominant in the Aru ice core. NH4+ accounted for 17% of the total ion concentration in the ER ice core but only 3% in the Aru ice core, which may be related to the Indian monsoon traveling over NH3 emission zones in southern Asia. The major soluble ion concentrations exhibited decreasing trends in the Aru ice core but increasing trends in the ER ice core (P < 0.01). Empirical orthogonal function and backward trajectory analyses indicated that the major soluble ions in the Aru ice core originated from crustal sources in central Asia; those in the ER ice core had crustal, anthropogenic, and oceanic sources from southern Asia. The results from the Aru ice core suggest that dust events and enhanced prevailing westerly winds promoted the deposition of dust aerosols from the Taklamakan Desert and arid and semi-arid regions of central Asia. Contrastingly, the results from the ER ice core suggest that the Indian monsoon transported crustal and anthropogenic sources from southern Asia and oceanic sources from the Bay of Bengal and Arabian Sea. This study contributes to the comprehensive understanding of the differences in glaciochemical records and their causes between the northwestern and southeastern TP.
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Affiliation(s)
- Dandan Yang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing 100101, China; University of Chinese Academy of Science, Beijing 100049, China
| | - Tandong Yao
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing 100101, China; Lanzhou University, Lanzhou 730000, China.
| | - Guangjian Wu
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing 100101, China
| | - Meilin Zhu
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing 100101, China
| | - Huabiao Zhao
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing 100101, China
| | - Yanyun Shi
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing 100101, China
| | - Dongmei Qu
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing 100101, China
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Climate change-induced population pressure drives high rates of lethal violence in the Prehispanic central Andes. Proc Natl Acad Sci U S A 2022; 119:e2117556119. [PMID: 35446706 PMCID: PMC9169923 DOI: 10.1073/pnas.2117556119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Understanding the influence of climate change and population pressure on human conflict remains a critically important topic in the social sciences. Long-term records that evaluate these dynamics across multiple centuries and outside the range of modern climatic variation are especially capable of elucidating the relative effect of—and the interaction between—climate and demography. This is crucial given that climate change may structure population growth and carrying capacity, while both climate and population influence per capita resource availability. This study couples paleoclimatic and demographic data with osteological evaluations of lethal trauma from 149 directly accelerator mass spectrometry 14C-dated individuals from the Nasca highland region of Peru. Multiple local and supraregional precipitation proxies are combined with a summed probability distribution of 149 14C dates to estimate population dynamics during a 700-y study window. Counter to previous findings, our analysis reveals a precipitous increase in violent deaths associated with a period of productive and stable climate, but volatile population dynamics. We conclude that favorable local climate conditions fostered population growth that put pressure on the marginal and highly circumscribed resource base, resulting in violent resource competition that manifested in over 450 y of internecine warfare. These findings help support a general theory of intergroup violence, indicating that relative resource scarcity—whether driven by reduced resource abundance or increased competition—can lead to violence in subsistence societies when the outcome is lower per capita resource availability.
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8
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Lapointe F, Bradley RS. Little Ice Age abruptly triggered by intrusion of Atlantic waters into the Nordic Seas. SCIENCE ADVANCES 2021; 7:eabi8230. [PMID: 34910526 PMCID: PMC8673760 DOI: 10.1126/sciadv.abi8230] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The Little Ice Age (LIA) was one of the coldest periods of the postglacial period in the Northern Hemisphere. Although there is increasing evidence that this time interval was associated with weakening of the subpolar gyre (SPG), the sequence of events that led to its weakened state has yet to be explained. Here, we show that the LIA was preceded by an exceptional intrusion of warm Atlantic water into the Nordic Seas in the late 1300s. The intrusion was a consequence of persistent atmospheric blocking over the North Atlantic, linked to unusually high solar activity. The warmer water led to the breakup of sea ice and calving of tidewater glaciers; weakening of the blocking anomaly in the late 1300s allowed the large volume of ice that had accumulated to be exported into the North Atlantic. This led to a weakening of the SPG, setting the stage for the subsequent LIA.
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Affiliation(s)
- Francois Lapointe
- Department of Geosciences, Climate System Research Center, University of Massachusetts Amherst, Amherst, MA, USA
| | - Raymond S Bradley
- Department of Geosciences, Climate System Research Center, University of Massachusetts Amherst, Amherst, MA, USA
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9
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Nelson EA, Buikstra JE, Herbig A, Tung TA, Bos KI. Advances in the molecular detection of tuberculosis in pre-contact Andean South America. INTERNATIONAL JOURNAL OF PALEOPATHOLOGY 2020; 29:128-140. [PMID: 31964606 DOI: 10.1016/j.ijpp.2019.12.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 12/06/2019] [Accepted: 12/13/2019] [Indexed: 06/10/2023]
Abstract
Andean paleopathological research has significantly enhanced knowledge about the geographical distribution and evolution of tuberculosis (TB) in pre-Columbian South America. In this paper, we review the history and progress of research on ancient tuberculosis (TB) in the Andean region, focusing on the strengths and limitations of current approaches for the molecular detection of ancient pathogens, with special attention to TB. As a case study, we describe a molecular screening approach for the detection of ancient Mycobacterium tuberculosis in individuals from Late Intermediate Period (1000-1400 CE) contexts at the site of Huari, Peru. We evaluate 34 commingled human vertebrae and combine morphological assessments of pathology with high throughput sequencing and a non-selective approach to ancient pathogen DNA screening. Our method enabled the simultaneous detection of ancient M. tuberculosis DNA and an evaluation of the environmental microbial composition of each sample. Our results show that despite the dominance of environmental DNA, molecular signatures of M. tuberculosis were identified in eight vertebrae, six of which had no observable skeletal pathology classically associated tuberculosis infection. This screening approach will assist in the identification of candidate samples for downstream genomic analyses. The method permits higher resolution disease identification in cases where pathology may be absent, or where the archaeological context may necessitate a broad differential diagnosis based on morphology alone.
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Affiliation(s)
- Elizabeth A Nelson
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Kahlaische Str 10, 07745 Jena, Germany; Eberhard Karls Universität Tübingen, Geschwister-Scholl-Platz, 72074 Tübingen, Germany.
| | - Jane E Buikstra
- Center for Bioarchaeological Research, Arizona State University, 1151 S. Forest Ave., Tempe, AZ, 85281, USA.
| | - Alexander Herbig
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Kahlaische Str 10, 07745 Jena, Germany.
| | - Tiffiny A Tung
- Department of Anthropology, Vanderbilt University, VU Station B #356050, Nashville, TN 37235, USA.
| | - Kirsten I Bos
- Department of Archaeogenetics, Max Planck Institute for the Science of Human History, Kahlaische Str 10, 07745 Jena, Germany.
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10
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Sandweiss DH, Andrus CFT, Kelley AR, Maasch KA, Reitz EJ, Roscoe PB. Archaeological climate proxies and the complexities of reconstructing Holocene El Niño in coastal Peru. Proc Natl Acad Sci U S A 2020; 117:8271-8279. [PMID: 32284418 PMCID: PMC7165442 DOI: 10.1073/pnas.1912242117] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Archaeological evidence plays a key role in longitudinal studies of humans and climate. Climate proxy data from Peruvian archaeological sites provide a case study through insight into the history of the "flavors" or varieties of El Niño (EN) events after ∼11 ka: eastern Pacific EN, La Niña, coastal EN (COA), and central Pacific or Modoki EN (CP). Archaeological proxies are important to the coastal Peruvian case because more commonly used paleoclimate proxies are unavailable or equivocal. Previously, multiproxy evidence from the Peruvian coast and elsewhere suggested that EN frequency varied over the Holocene: 1) present in the Early Holocene; 2) absent or very low frequency during the Middle Holocene (∼9 to 6 ka); 3) low after ∼6 ka; and 4) rapidly increasing frequency after 3 ka. Despite skepticism about the reliability of archaeological proxies, nonarchaeological proxies seemed to confirm this archaeological EN reconstruction. Although there is consensus that EN frequency varied over this period, some nonarchaeological and archaeological proxies call parts of this reconstruction into question. Here we review Holocene EN frequency reconstructions for the Peruvian coast, point to complexities introduced by apparent contradictions in a range of proxy records, consider the impact of CP and COA phenomena, and assess the merits of archaeological proxies in EN reconstructions. Reconciling Peruvian coastal paleoclimate data is critical for testing models of future EN behavior under climate variability.
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Affiliation(s)
- Daniel H Sandweiss
- Department of Anthropology, University of Maine, Orono, ME 04469;
- Climate Change Institute, University of Maine, Orono, ME 04469
| | - C Fred T Andrus
- Department of Geological Sciences, University of Alabama, Tuscaloosa, AL 35487
| | - Alice R Kelley
- Climate Change Institute, University of Maine, Orono, ME 04469
- School of Earth and Climate Sciences, University of Maine, Orono, ME 04469
| | - Kirk A Maasch
- Climate Change Institute, University of Maine, Orono, ME 04469
- School of Earth and Climate Sciences, University of Maine, Orono, ME 04469
| | - Elizabeth J Reitz
- Georgia Museum of Natural History, University of Georgia, Athens, GA 30602
| | - Paul B Roscoe
- Department of Anthropology, University of Maine, Orono, ME 04469
- Climate Change Institute, University of Maine, Orono, ME 04469
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11
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Michelutti N, Sowell P, Tapia PM, Grooms C, Polo M, Gambetta A, Ausejo C, Smol JP. A pre-Inca pot from underwater ruins discovered in an Andean lake provides a sedimentary record of marked hydrological change. Sci Rep 2019; 9:19193. [PMID: 31844075 PMCID: PMC6915777 DOI: 10.1038/s41598-019-55422-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 11/25/2019] [Indexed: 11/20/2022] Open
Abstract
Pre-Hispanic artifacts and sacred architecture were recently discovered submerged in a large lake (Laguna Sibinacocha) in the Peruvian Andes. The underwater ruins indicate a dramatic shift in the region’s hydrology but the timing and triggers of this shift remain unknown. In a novel approach blending archaeology and paleoecology, we analyzed a sediment sequence from within one of the recovered artifacts, specifically a pot from the Late Intermediate Period (~1000–1400 CE). Radioisotopic dating of discrete sediment intervals sampled from the pot show a stratigraphically intact profile that preserves a history of change at this site. The pot’s basal sediment age places the timing of lake-level rise at ~1600 CE, which post-dates the end of the Inca Empire (1400–1532 CE) by several decades. The ubiquity of planktonic algae throughout the sediment profile suggests water levels remained high above the pot since its submergence. Paleoclimate data from the nearby Quelccaya ice core records indicate lake flooding followed a pronounced wet period beginning ~1520 CE. These data show the permanence of mean state changes in climate on the region’s hydrology, with clear implications for the study site (an important water resource for ~500,000 people) and other lakes in the rapidly warming Andes.
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Affiliation(s)
- Neal Michelutti
- Paleoecological Environmental Assessment and Research Laboratory (PEARL), Department of Biology, Queen's University, Kingston, Ontario, Canada.
| | | | - Pedro M Tapia
- INAIGEM - Dirección de Investigación en Ecosistemas de Montañas, Huaraz, Perú
| | - Christopher Grooms
- Paleoecological Environmental Assessment and Research Laboratory (PEARL), Department of Biology, Queen's University, Kingston, Ontario, Canada
| | - Martin Polo
- El Centro Peruano de Arqueología Marítima y Subaquática [CPAMS], Lima, Peru
| | | | - Carlos Ausejo
- El Centro Peruano de Arqueología Marítima y Subaquática [CPAMS], Lima, Peru
| | - John P Smol
- Paleoecological Environmental Assessment and Research Laboratory (PEARL), Department of Biology, Queen's University, Kingston, Ontario, Canada
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12
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Disappearance of the last tropical glaciers in the Western Pacific Warm Pool (Papua, Indonesia) appears imminent. Proc Natl Acad Sci U S A 2019; 116:26382-26388. [PMID: 31818944 DOI: 10.1073/pnas.1822037116] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The glaciers near Puncak Jaya in Papua, Indonesia, the highest peak between the Himalayas and the Andes, are the last remaining tropical glaciers in the West Pacific Warm Pool (WPWP). Here, we report the recent, rapid retreat of the glaciers near Puncak Jaya by quantifying the loss of ice coverage and reduction of ice thickness over the last 8 y. Photographs and measurements of a 30-m accumulation stake anchored to bedrock on the summit of one of these glaciers document a rapid pace in the loss of ice cover and a ∼5.4-fold increase in the thinning rate, which was augmented by the strong 2015-2016 El Niño. At the current rate of ice loss, these glaciers will likely disappear within the next decade. To further understand the mechanisms driving the observed retreat of these glaciers, 2 ∼32-m-long ice cores to bedrock recovered in mid-2010 are used to reconstruct the tropical Pacific climate variability over approximately the past half-century on a quasi-interannual timescale. The ice core oxygen isotopic ratios show a significant positive linear trend since 1964 CE (0.018 ± 0.008‰ per year; P < 0.03) and also suggest that the glaciers' retreat is augmented by El Niño-Southern Oscillation processes, such as convection and warming of the atmosphere and sea surface. These Papua glaciers provide the only tropical records of ice core-derived climate variability for the WPWP.
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13
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Sanz Rodriguez E, Plummer C, Nation M, Moy A, Curran M, Haddad PR, Paull B. Sub-1 mL sample requirement for simultaneous determination of 17 organic and inorganic anions and cations in Antarctic ice core samples by dual capillary ion chromatography. Anal Chim Acta 2019; 1063:167-177. [PMID: 30967181 DOI: 10.1016/j.aca.2019.02.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 02/08/2019] [Accepted: 02/09/2019] [Indexed: 11/26/2022]
Abstract
The significant advance of delivering high value multi-species data from sub-1 mL ice core sample volumes allows higher temporal resolution in deposition records of inorganic and low molecular weight organic anions and cations. The determination of these species is a fundamental strategic requirement in modern paleoclimate studies. Herein, for the first time, a dual capillary ion chromatography (Cap-IC) based method for the simultaneous separation of 17 organic and inorganic anions and cations in low volume Antarctic ice core samples is presented. The total amount of sample required for direct injection has been reduced to 190 μL, which is 35 times lower than the amount of sample required by standard ion chromatography methods. A dual Cap-IC system configured for the simultaneous determination of cations and anions was used throughout. A range of chromatographic parameters was optimised for both anion and cation systems to obtain baseline separations of all target analytes in a suitable run time and to minimise the amount of sample required. Baseline separation of matrix and trace 'marker' ions were achieved in less than 35 min, after injecting only 40 μL of sample in each IC system. Limits of detection (LODs) for all analytes determined were within a range similar to that achieved by previously published standard bore IC-based methods. Intra- and inter-day repeatability were evaluated, with both parameters being typically below 3% for peak area. In further validation of the method, a comparative analysis of a set of 420 ice core samples from Aurora Basin North site, Antarctica, previously analysed by standard IC, established that the proposed low sample volume technique was applicable as a routine measurement approach in ice core analysis projects.
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Affiliation(s)
- Estrella Sanz Rodriguez
- Australian Centre for Research on Separation Science, School of Natural Sciences, University of Tasmania, GPO Box 252-75, Hobart, Tasmania, 7001, Australia.
| | - Christopher Plummer
- Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, GPO Box 252-80, Hobart, Tasmania, 7001, Australia
| | - Meredith Nation
- Australian Antarctic Division, 203 Channel Highway, Kingston, Tasmania, 7050, Australia
| | - Andrew Moy
- Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, GPO Box 252-80, Hobart, Tasmania, 7001, Australia; Australian Antarctic Division, 203 Channel Highway, Kingston, Tasmania, 7050, Australia
| | - Mark Curran
- Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, GPO Box 252-80, Hobart, Tasmania, 7001, Australia; Australian Antarctic Division, 203 Channel Highway, Kingston, Tasmania, 7050, Australia
| | - Paul R Haddad
- Australian Centre for Research on Separation Science, School of Natural Sciences, University of Tasmania, GPO Box 252-75, Hobart, Tasmania, 7001, Australia
| | - Brett Paull
- Australian Centre for Research on Separation Science, School of Natural Sciences, University of Tasmania, GPO Box 252-75, Hobart, Tasmania, 7001, Australia
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14
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Projections of the future disappearance of the Quelccaya Ice Cap in the Central Andes. Sci Rep 2018; 8:15564. [PMID: 30349015 PMCID: PMC6197230 DOI: 10.1038/s41598-018-33698-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 10/02/2018] [Indexed: 11/24/2022] Open
Abstract
We analyze the future state of Quelccaya Ice Cap (QIC), the world’s largest tropical ice cap with a summit elevation of 5680 m a.s.l., which, in terms of its elevation range (~5300–5680 m a.s.l.), is representative of many low-elevation glacierized sites in the tropical Andes. CMIP5 model projections of air temperature (Ta) at QIC indicate a warming of about 2.4 °C and 5.4 °C (respectively) for RCP4.5 and RCP8.5 scenarios by the end of the 21st century, resulting in a pronounced increase in freezing level height (FLH). The impact of this warming on the QIC was quantified using equilibrium-line altitude (ELA) projections. The change in the ELA was quantified based on an empirical ELA–FLH relationship, and calibrated with observations of the highest annual snowline altitude (SLA) derived from LANDSAT data. Results show that from the mid-2050s onwards, the ELA will be located above the QIC summit in the RCP8.5 scenario. At that time, surface mass balance at QIC and most tropical glaciers at similar elevations will become increasingly negative, leading to their eventual complete disappearance. Our analysis further corroborates that elevation-dependent warming (EDW) contributes significantly to the enhanced warming over the QIC, and that EDW at Quelccaya depends on the rate of anthropogenic forcing.
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15
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Mentzafou A, Wagner S, Dimitriou E. Historical trends and the long-term changes of the hydrological cycle components in a Mediterranean river basin. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 636:558-568. [PMID: 29719279 DOI: 10.1016/j.scitotenv.2018.04.298] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 11/30/2017] [Accepted: 04/22/2018] [Indexed: 06/08/2023]
Abstract
Identifying the historical hydrometeorological trends in a river basin is necessary for understanding the dominant interactions between climate, human activities and local hydromorphological conditions. Estimating the hydrological reference conditions in a river is also crucial for estimating accurately the impacts from human water related activities and design appropriate water management schemes. In this effort, the output of a regional past climate model was used, covering the period from 1660 to 1990, in combination with a dynamic, spatially distributed, hydrologic model to estimate the past and recent trends in the main hydrologic parameters such as overland flow, water storages and evapotranspiration, in a Mediterranean river basin. The simulated past hydrologic conditions (1660-1960) were compared with the current hydrologic regime (1960-1990), to assess the magnitude of human and natural impacts on the identified hydrologic trends. The hydrological components of the recent period of 2008-2016 were also examined in relation to the impact of human activities. The estimated long-term trends of the hydrologic parameters were partially assigned to varying atmospheric forcing due to volcanic activity combined with spontaneous meteorological fluctuations.
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Affiliation(s)
- A Mentzafou
- Hellenic Centre for Marine Research, Institute of Marine Biological Resources and Inland Waters, 46.7 km of Athens - Sounio Ave., 19013 Anavissos Attikis, Greece
| | - S Wagner
- Helmholtz-Zentrum Geesthacht, Institute for Coastal Research, Department of Paleoclimate and Statistics, Max-Planck-Straße 1, 21502 Geesthacht, Germany
| | - E Dimitriou
- Hellenic Centre for Marine Research, Institute of Marine Biological Resources and Inland Waters, 46.7 km of Athens - Sounio Ave., 19013 Anavissos Attikis, Greece.
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16
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17
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Chen F, Zhang M, Wang S, Qiu X, Du M. Environmental controls on stable isotopes of precipitation in Lanzhou, China: An enhanced network at city scale. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 609:1013-1022. [PMID: 28783912 DOI: 10.1016/j.scitotenv.2017.07.216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 07/23/2017] [Accepted: 07/24/2017] [Indexed: 06/07/2023]
Abstract
Stable hydrogen and oxygen isotopes in precipitation are very sensitive to environmental changes, and can record evolution of water cycle. The Lanzhou city in northwestern China is jointly influenced by the monsoon and westerlies, which is considered as a vital platform to investigate the moisture regime for this region. Since 2011, an observation network of stable isotopes in precipitation was established across the city, and four stations were included in the network. In 2013, six more sampling stations were added, and the enhanced network might provide more meaningful information on spatial incoherence and synoptic process. This study focused on the variations of stable isotopes (δ18O and δD) in precipitation and the environmental controls based on the 1432 samples in this enhanced network from April 2011 to October 2014. The results showed that the precipitation isotopes had great spatial diversity, and the neighboring stations may present large difference in δD and δ18O. Based on the observation at ten sampling sites, an isoscape in precipitation was calculated, and the method is useful to produce isoscape for small domains. The temperature effect and amount effect was reconsidered based on the dataset. Taking meteorological parameters (temperature, precipitation amount, relative humidity, water vapor pressure and dew point temperature) as variables in a multi-linear regression, the result of coefficients for these meteorological parameters were calculated. Some cases were also involved in this study, and the isotopic characteristics during one event or continuous days were used to understand the environmental controls on precipitation isotopes.
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Affiliation(s)
- Fenli Chen
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, China.
| | - Mingjun Zhang
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, China.
| | - Shengjie Wang
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, China.
| | - Xue Qiu
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, China.
| | - Mingxia Du
- College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, China.
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18
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A global multiproxy database for temperature reconstructions of the Common Era. Sci Data 2017; 4:170088. [PMID: 28696409 PMCID: PMC5505119 DOI: 10.1038/sdata.2017.88] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 05/03/2017] [Indexed: 11/08/2022] Open
Abstract
Reproducible climate reconstructions of the Common Era (1 CE to present) are key to placing industrial-era warming into the context of natural climatic variability. Here we present a community-sourced database of temperature-sensitive proxy records from the PAGES2k initiative. The database gathers 692 records from 648 locations, including all continental regions and major ocean basins. The records are from trees, ice, sediment, corals, speleothems, documentary evidence, and other archives. They range in length from 50 to 2000 years, with a median of 547 years, while temporal resolution ranges from biweekly to centennial. Nearly half of the proxy time series are significantly correlated with HadCRUT4.2 surface temperature over the period 1850-2014. Global temperature composites show a remarkable degree of coherence between high- and low-resolution archives, with broadly similar patterns across archive types, terrestrial versus marine locations, and screening criteria. The database is suited to investigations of global and regional temperature variability over the Common Era, and is shared in the Linked Paleo Data (LiPD) format, including serializations in Matlab, R and Python.
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19
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Recent enhancement of central Pacific El Niño variability relative to last eight centuries. Nat Commun 2017; 8:15386. [PMID: 28555638 PMCID: PMC5459944 DOI: 10.1038/ncomms15386] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Accepted: 03/27/2017] [Indexed: 11/30/2022] Open
Abstract
The far-reaching impacts of central Pacific El Niño events on global climate differ appreciably from those associated with eastern Pacific El Niño events. Central Pacific El Niño events may become more frequent in coming decades as atmospheric greenhouse gas concentrations rise, but the instrumental record of central Pacific sea-surface temperatures is too short to detect potential trends. Here we present an annually resolved reconstruction of NIÑO4 sea-surface temperature, located in the central equatorial Pacific, based on oxygen isotopic time series from Taiwan tree cellulose that span from 1190 AD to 2007 AD. Our reconstruction indicates that relatively warm Niño4 sea-surface temperature values over the late twentieth century are accompanied by higher levels of interannual variability than observed in other intervals of the 818-year-long reconstruction. Our results imply that anthropogenic greenhouse forcing may be driving an increase in central Pacific El Niño-Southern Oscillation variability and/or its hydrological impacts, consistent with recent modelling studies. El Niño events in the Central Pacific may be changing due to climate change, but long records to support this are lacking. Here, the authors present sea surface temperature reconstructions from tree cellulose for the last 800 years which suggest the variability of Central Pacific El Niño events has increased.
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20
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Putnam AE, Broecker WS. Human-induced changes in the distribution of rainfall. SCIENCE ADVANCES 2017; 3:e1600871. [PMID: 28580418 PMCID: PMC5451196 DOI: 10.1126/sciadv.1600871] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 04/13/2017] [Indexed: 05/24/2023]
Abstract
A likely consequence of global warming will be the redistribution of Earth's rain belts, affecting water availability for many of Earth's inhabitants. We consider three ways in which planetary warming might influence the global distribution of precipitation. The first possibility is that rainfall in the tropics will increase and that the subtropics and mid-latitudes will become more arid. A second possibility is that Earth's thermal equator, around which the planet's rain belts and dry zones are organized, will migrate northward. This northward shift will be a consequence of the Northern Hemisphere, with its large continental area, warming faster than the Southern Hemisphere, with its large oceanic area. A third possibility is that both of these scenarios will play out simultaneously. We review paleoclimate evidence suggesting that (i) the middle latitudes were wetter during the last glacial maximum, (ii) a northward shift of the thermal equator attended the abrupt Bølling-Allerød climatic transition ~14.6 thousand years ago, and (iii) a southward shift occurred during the more recent Little Ice Age. We also inspect trends in seasonal surface heating between the hemispheres over the past several decades. From these clues, we predict that there will be a seasonally dependent response in rainfall patterns to global warming. During boreal summer, in which the rate of recent warming has been relatively uniform between the hemispheres, wet areas will get wetter and dry regions will become drier. During boreal winter, rain belts and drylands will expand northward in response to differential heating between the hemispheres.
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Affiliation(s)
- Aaron E. Putnam
- School of Earth and Climate Sciences and Climate Change Institute, 224 Bryand Global Sciences Center, University of Maine, Orono, ME 04469, USA
- Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W/PO Box 1000, Palisades, NY 10964, USA
| | - Wallace S. Broecker
- Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W/PO Box 1000, Palisades, NY 10964, USA
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21
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Tropical rainfall over the last two millennia: evidence for a low-latitude hydrologic seesaw. Sci Rep 2017; 7:45809. [PMID: 28378755 PMCID: PMC5381098 DOI: 10.1038/srep45809] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 03/06/2017] [Indexed: 12/03/2022] Open
Abstract
The presence of a low- to mid-latitude interhemispheric hydrologic seesaw is apparent over orbital and glacial-interglacial timescales, but its existence over the most recent past remains unclear. Here we investigate, based on climate proxy reconstructions from both hemispheres, the inter-hemispherical phasing of the Intertropical Convergence Zone (ITCZ) and the low- to mid-latitude teleconnections in the Northern Hemisphere over the past 2000 years. A clear feature is a persistent southward shift of the ITCZ during the Little Ice Age until the beginning of the 19th Century. Strong covariation between our new composite ITCZ-stack and North Atlantic Oscillation (NAO) records reveals a tight coupling between these two synoptic weather and climate phenomena over decadal-to-centennial timescales. This relationship becomes most apparent when comparing two precisely dated, high-resolution paleorainfall records from Belize and Scotland, indicating that the low- to mid-latitude teleconnection was also active over annual-decadal timescales. It is likely a combination of external forcing, i.e., solar and volcanic, and internal feedbacks, that drives the synchronous ITCZ and NAO shifts via energy flux perturbations in the tropics.
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22
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Freeze-thaw revival of rotifers and algae in a desiccated, high-elevation (5500 meters) microbial mat, high Andes, Perú. Extremophiles 2017; 21:573-580. [PMID: 28321614 DOI: 10.1007/s00792-017-0926-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 03/06/2017] [Indexed: 12/24/2022]
Abstract
This is the first study of the highest elevation cyanobacteria-dominated microbial mat yet described. The desiccated mat was sampled in 2010 from an ephemeral rock pool at 5500 m above sea level in the Cordillera Vilcanota of southern Perú. After being frozen for 6 years at -20 °C in the lab, pieces of the mat were sequenced to fully characterize both the 16 and 18S microbial communities and experiments were conducted to determine if organisms in the mat could revive and become active under the extreme freeze-thaw conditions that these mats experience in the field. Sequencing revealed an unexpectedly diverse, multi-trophic microbial community with 16S OTU richness comparable to similar, seasonally desiccated mats from the Dry Valleys of Antarctica and low elevation sites in the Atacama Desert region. The bacterial community of the mat was dominated by phototrophs in the Cyanobacteria (Nostoc) and the Rhodospirillales, whereas the eukaryotic community was dominated by predators such as bdelloid rotifers (Philodinidae). Microcosm experiments showed that bdelloid rotifers in the mat were able to come out of dormancy and actively forage even under realistic field conditions (diurnal temperature fluctuations of -12 °C at night to + 27 °C during the day), and after being frozen for 6 years. Our results broaden our understanding of the diversity of life in periodically desiccated, high-elevation habitats and demonstrate that extreme freeze-thaw cycles per se are not a major factor limiting the development of at least some members of these unique microbial mat systems.
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23
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Baldini LM, Baldini JUL, McElwaine JN, Frappier AB, Asmerom Y, Liu KB, Prufer KM, Ridley HE, Polyak V, Kennett DJ, Macpherson CG, Aquino VV, Awe J, Breitenbach SFM. Persistent northward North Atlantic tropical cyclone track migration over the past five centuries. Sci Rep 2016; 6:37522. [PMID: 27876831 PMCID: PMC5120344 DOI: 10.1038/srep37522] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 10/31/2016] [Indexed: 11/24/2022] Open
Abstract
Accurately predicting future tropical cyclone risk requires understanding the fundamental controls on tropical cyclone dynamics. Here we present an annually-resolved 450-year reconstruction of western Caribbean tropical cyclone activity developed using a new coupled carbon and oxygen isotope ratio technique in an exceptionally well-dated stalagmite from Belize. Western Caribbean tropical cyclone activity peaked at 1650 A.D., coincident with maximum Little Ice Age cooling, and decreased gradually until the end of the record in 1983. Considered with other reconstructions, the new record suggests that the mean track of Cape Verde tropical cyclones shifted gradually north-eastward from the western Caribbean toward the North American east coast over the last 450 years. Since ~1870 A.D., these shifts were largely driven by anthropogenic greenhouse gas and sulphate aerosol emissions. Our results strongly suggest that future emission scenarios will result in more frequent tropical cyclone impacts on the financial and population centres of the northeastern United States.
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Affiliation(s)
- Lisa M Baldini
- Department of Earth Sciences, Durham University, Durham, DH1 3LE, UK
| | - James U L Baldini
- Department of Earth Sciences, Durham University, Durham, DH1 3LE, UK
| | - Jim N McElwaine
- Department of Earth Sciences, Durham University, Durham, DH1 3LE, UK
| | - Amy Benoit Frappier
- Department of Geosciences, Skidmore College, 815 North Broadway, Saratoga Springs, New York, 12866, USA
| | - Yemane Asmerom
- Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87106, USA
| | - Kam-Biu Liu
- Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Keith M Prufer
- Department of Anthropology, University of New Mexico, Albuquerque, NM 87106, USA
| | - Harriet E Ridley
- Department of Earth Sciences, Durham University, Durham, DH1 3LE, UK
| | - Victor Polyak
- Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87106, USA
| | - Douglas J Kennett
- Department of Anthropology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | | | - Valorie V Aquino
- Department of Anthropology, University of New Mexico, Albuquerque, NM 87106, USA
| | - Jaime Awe
- Institute of Archaeology, Belmopan, Belize.,Department of Anthropology, Northern Arizona University, Flagstaff, AZ 86011-5200, USA
| | - Sebastian F M Breitenbach
- Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ, UK.,Institute for Geology, Mineralogy &Geophysics, Ruhr-Universität Bochum, Unversitätsstr. 150, 44801, Bochum, Germany
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24
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Griffiths ML, Kimbrough AK, Gagan MK, Drysdale RN, Cole JE, Johnson KR, Zhao JX, Cook BI, Hellstrom JC, Hantoro WS. Western Pacific hydroclimate linked to global climate variability over the past two millennia. Nat Commun 2016; 7:11719. [PMID: 27271972 PMCID: PMC4899856 DOI: 10.1038/ncomms11719] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 04/25/2016] [Indexed: 11/09/2022] Open
Abstract
Interdecadal modes of tropical Pacific ocean-atmosphere circulation have a strong influence on global temperature, yet the extent to which these phenomena influence global climate on multicentury timescales is still poorly known. Here we present a 2,000-year, multiproxy reconstruction of western Pacific hydroclimate from two speleothem records for southeastern Indonesia. The composite record shows pronounced shifts in monsoon rainfall that are antiphased with precipitation records for East Asia and the central-eastern equatorial Pacific. These meridional and zonal patterns are best explained by a poleward expansion of the Australasian Intertropical Convergence Zone and weakening of the Pacific Walker circulation (PWC) between ∼1000 and 1500 CE Conversely, an equatorward contraction of the Intertropical Convergence Zone and strengthened PWC occurred between ∼1500 and 1900 CE. Our findings, together with climate model simulations, highlight the likelihood that century-scale variations in tropical Pacific climate modes can significantly modulate radiatively forced shifts in global temperature. Interdecadal modes of tropical Pacific ocean-atmosphere circulation have a strong influence on global temperature. Here, the authors present a 2000-year hydroclimate record from the Indo-Pacific, which suggests that century-scale variations in these modes are also linked with global temperature variability.
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Affiliation(s)
- Michael L Griffiths
- Department of Environmental Science, William Paterson University, Wayne, New Jersey 07470, USA
| | - Alena K Kimbrough
- Research School of Earth Sciences, Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | - Michael K Gagan
- Research School of Earth Sciences, Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | - Russell N Drysdale
- School of Geography, University of Melbourne, Parkville, Victoria 3010, Australia.,EDYTEM, UMR CNRS 5204, Université de Savoie, 73376 Le Bourget du Lac, France
| | - Julia E Cole
- Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA.,Department of Atmospheric Sciences, University of Arizona, Tucson, Arizona 85721, USA
| | - Kathleen R Johnson
- Department of Earth System Science, University of California, Irvine, California 92697-3100, USA
| | - Jian-Xin Zhao
- School of Earth Sciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Benjamin I Cook
- NASA Goddard Institute for Space Studies, New York, New York 10025, USA
| | - John C Hellstrom
- School of Earth Sciences, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Wahyoe S Hantoro
- Research Center for Geotechnology, Indonesian Institute of Sciences, Bandung 40135, Indonesia
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25
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van Hengstum PJ, Donnelly JP, Fall PL, Toomey MR, Albury NA, Kakuk B. The intertropical convergence zone modulates intense hurricane strikes on the western North Atlantic margin. Sci Rep 2016; 6:21728. [PMID: 26906670 PMCID: PMC4764861 DOI: 10.1038/srep21728] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 01/29/2016] [Indexed: 11/23/2022] Open
Abstract
Most Atlantic hurricanes form in the Main Development Region between 9°N to 20°N along the northern edge of the Intertropical Convergence Zone (ITCZ). Previous research has suggested that meridional shifts in the ITCZ position on geologic timescales can modulate hurricane activity, but continuous and long-term storm records are needed from multiple sites to assess this hypothesis. Here we present a 3000 year record of intense hurricane strikes in the northern Bahamas (Abaco Island) based on overwash deposits in a coastal sinkhole, which indicates that the ITCZ has likely helped modulate intense hurricane strikes on the western North Atlantic margin on millennial to centennial-scales. The new reconstruction closely matches a previous reconstruction from Puerto Rico, and documents a period of elevated intense hurricane activity on the western North Atlantic margin from 2500 to 1000 years ago when paleo precipitation proxies suggest that the ITCZ occupied a more northern position. Considering that anthropogenic warming is predicted to be focused in the northern hemisphere in the coming century, these results provide a prehistoric analog that an attendant northern ITCZ shift in the future may again return the western North Atlantic margin to an active hurricane interval.
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Affiliation(s)
- Peter J van Hengstum
- Texas A&M University at Galveston, Department of Marine Sciences, Galveston, Texas, 77554.,Texas A&M University, Department of Oceanography, College Station, Texas, 77843
| | - Jeffrey P Donnelly
- Woods Hole Oceanographic Institution, Department of Geology and Geophysics, Woods Hole, Massachusetts, 02543, USA
| | - Patricia L Fall
- University of North Carolina Charlotte, Department of Geography and Earth Sciences, Charlotte, North Carolina, 28223, USA
| | - Michael R Toomey
- U.S. Geological Survey, Eastern Geology and Paleoclimate Science Center, Reston, VA, 20192
| | - Nancy A Albury
- Antiquities, Monuments, and Museums Corporation/National Museum of The Bahamas, PO Box EE-15082, Nassau, The Bahamas
| | - Brian Kakuk
- Bahamas Underground, Marsh Harbour, Abaco Island, The Bahamas
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Rustic GT, Koutavas A, Marchitto TM, Linsley BK. Dynamical excitation of the tropical Pacific Ocean and ENSO variability by Little Ice Age cooling. Science 2015; 350:1537-41. [PMID: 26634438 DOI: 10.1126/science.aac9937] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 11/18/2015] [Indexed: 11/02/2022]
Abstract
Tropical Pacific Ocean dynamics during the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA) are poorly characterized due to a lack of evidence from the eastern equatorial Pacific. We reconstructed sea surface temperature, El Niño-Southern Oscillation (ENSO) activity, and the tropical Pacific zonal gradient for the past millennium from Galápagos ocean sediments. We document a mid-millennium shift (MMS) in ocean-atmosphere circulation around 1500-1650 CE, from a state with dampened ENSO and strong zonal gradient to one with amplified ENSO and weak gradient. The MMS coincided with the deepest LIA cooling and was probably caused by a southward shift of the intertropical convergence zone. The peak of the MCA (900-1150 CE) was a warm period in the eastern Pacific, contradicting the paradigm of a persistent La Niña pattern.
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Affiliation(s)
- Gerald T Rustic
- Department of Engineering Science and Physics, College of Staten Island, City University of New York, Staten Island, NY 10314, USA. Doctoral Program in Earth and Environmental Sciences, Graduate Center of the City University of New York, New York, NY 10016, USA.
| | - Athanasios Koutavas
- Department of Engineering Science and Physics, College of Staten Island, City University of New York, Staten Island, NY 10314, USA. Doctoral Program in Earth and Environmental Sciences, Graduate Center of the City University of New York, New York, NY 10016, USA. Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964, USA
| | - Thomas M Marchitto
- Department of Geological Sciences and Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO 80309, USA
| | - Braddock K Linsley
- Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964, USA
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Kennett DJ, Marwan N. Climatic volatility, agricultural uncertainty, and the formation, consolidation and breakdown of preindustrial agrarian states. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2015; 373:rsta.2014.0458. [PMID: 26460110 DOI: 10.1098/rsta.2014.0458] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The episodic formation, consolidation and breakdown of preindustrial states occurred in multiple contexts worldwide during the last 5000 years and are contingent upon interacting endogenous economic, demographic and political mechanisms. In some instances, there is support for climate change stimulating integration or inducing sociopolitical fragmentation in these complex systems. Here, we build upon this paradigm and introduce the hypothesis that stable climatic conditions favour the formation of agrarian states, while persistently volatile climatic conditions can contribute to the episodic collapse of these complex societies. It is generally recognized that agrarian economies underwrite preindustrial state-level societies. In these contexts, the economic uncertainty associated with highly volatile climatic regimes makes it difficult for individuals or institutions to determine the costs and benefits of one agricultural strategy over another. We argue that this fosters sociopolitical instability and decentralization. As a first test of this hypothesis, we examine the historical dynamics of state formation and decline in the Mexican and Andean highlands within the last 2000 years. The available data in these regions are consistent with the hypothesis that the formation and consolidation of regional polities and empires is favoured in stable climatic regimes and that political decentralization can be stimulated and perpetuated by highly volatile climatic conditions.
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Affiliation(s)
- Douglas J Kennett
- Department of Anthropology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Norbert Marwan
- Potsdam Institute for Climate Impact Research, PO Box 60 12 03, Potsdam 14412, Germany
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Fehren-Schmitz L, Llamas B, Lindauer S, Tomasto-Cagigao E, Kuzminsky S, Rohland N, Santos FR, Kaulicke P, Valverde G, Richards SM, Nordenfelt S, Seidenberg V, Mallick S, Cooper A, Reich D, Haak W. A Re-Appraisal of the Early Andean Human Remains from Lauricocha in Peru. PLoS One 2015; 10:e0127141. [PMID: 26061688 PMCID: PMC4464891 DOI: 10.1371/journal.pone.0127141] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 04/13/2015] [Indexed: 11/18/2022] Open
Abstract
The discovery of human remains from the Lauricocha cave in the Central Andean highlands in the 1960's provided the first direct evidence for human presence in the high altitude Andes. The skeletons found at this site were ascribed to the Early to Middle Holocene and represented the oldest known population of Western South America, and thus were used in several studies addressing the early population history of the continent. However, later excavations at Lauricocha led to doubts regarding the antiquity of the site. Here, we provide new dating, craniometric, and genetic evidence for this iconic site. We obtained new radiocarbon dates, generated complete mitochondrial genomes and nuclear SNP data from five individuals, and re-analyzed the human remains of Lauricocha to revise the initial morphological and craniometric analysis conducted in the 1960's. We show that Lauricocha was indeed occupied in the Early to Middle Holocene but the temporal spread of dates we obtained from the human remains show that they do not qualify as a single contemporaneous population. However, the genetic results from five of the individuals fall within the spectrum of genetic diversity observed in pre-Columbian and modern Native Central American populations.
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Affiliation(s)
- Lars Fehren-Schmitz
- Department of Anthropology, University of California Santa Cruz, Santa Cruz, California, United States of America
- Historical Anthropology and Human Ecology, University Goettingen, Goettingen, Lower Saxony, Germany
- * E-mail:
| | - Bastien Llamas
- Australian Centre for Ancient DNA, School of Biological Sciences, The University of Adelaide, South Australia, Australia
| | - Susanne Lindauer
- Curt-Engelhorn-Center for Archaeometry, Mannheim, Baden-Württemberg, Germany
| | - Elsa Tomasto-Cagigao
- Departamento de Humanidades, Pontificia Universidad Católica del Perú, Lima, Perú
| | - Susan Kuzminsky
- Department of Anthropology, University of California Santa Cruz, Santa Cruz, California, United States of America
- Instituto de Investigaciones Arqueológicas y Museo, Universidad Católica del Norte, San Pedro de Atacama, Antofagasta, Chile
| | - Nadin Rohland
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Fabrício R. Santos
- Departamento de Biologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Peter Kaulicke
- Departamento de Humanidades, Pontificia Universidad Católica del Perú, Lima, Perú
| | - Guido Valverde
- Australian Centre for Ancient DNA, School of Biological Sciences, The University of Adelaide, South Australia, Australia
| | - Stephen M. Richards
- Australian Centre for Ancient DNA, School of Biological Sciences, The University of Adelaide, South Australia, Australia
| | - Susanne Nordenfelt
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Verena Seidenberg
- Historical Anthropology and Human Ecology, University Goettingen, Goettingen, Lower Saxony, Germany
| | - Swapan Mallick
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Alan Cooper
- Australian Centre for Ancient DNA, School of Biological Sciences, The University of Adelaide, South Australia, Australia
| | - David Reich
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
- Broad Institute of Harvard and MIT, Cambridge, Massachusetts, United States of America
- Howard Hughes Medical Institute, Boston, Massachusetts, United States of America
| | - Wolfgang Haak
- Australian Centre for Ancient DNA, School of Biological Sciences, The University of Adelaide, South Australia, Australia
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Lewis SL, Maslin MA. Defining the Anthropocene. Nature 2015; 519:171-80. [DOI: 10.1038/nature14258] [Citation(s) in RCA: 1488] [Impact Index Per Article: 165.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 01/12/2015] [Indexed: 11/09/2022]
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Widespread pollution of the South American atmosphere predates the industrial revolution by 240 y. Proc Natl Acad Sci U S A 2015; 112:2349-54. [PMID: 25675506 DOI: 10.1073/pnas.1421119112] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In the Southern Hemisphere, evidence for preindustrial atmospheric pollution is restricted to a few geological archives of low temporal resolution that record trace element deposition originating from past mining and metallurgical operations in South America. Therefore, the timing and the spatial impact of these activities on the past atmosphere remain poorly constrained. Here we present an annually resolved ice core record (A.D. 793-1989) from the high-altitude drilling site of Quelccaya (Peru) that archives preindustrial and industrial variations in trace elements. During the precolonial period (i.e., pre-A.D. 1532), the deposition of trace elements was mainly dominated by the fallout of aeolian dust and of ash from occasional volcanic eruptions, indicating that metallurgic production during the Inca Empire (A.D. 1438-1532) had a negligible impact on the South American atmosphere. In contrast, a widespread anthropogenic signal is evident after around A.D. 1540, which corresponds with the beginning of colonial mining and metallurgy in Peru and Bolivia, ∼240 y before the Industrial Revolution. This shift was due to a major technological transition for silver extraction in South America (A.D. 1572), from lead-based smelting to mercury amalgamation, which precipitated a massive increase in mining activities. However, deposition of toxic trace metals during the Colonial era was still several factors lower than 20th century pollution that was unprecedented over the entirety of human history.
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Uetake J, Tanaka S, Hara K, Tanabe Y, Samyn D, Motoyama H, Imura S, Kohshima S. Novel biogenic aggregation of moss gemmae on a disappearing African glacier. PLoS One 2014; 9:e112510. [PMID: 25401789 PMCID: PMC4234412 DOI: 10.1371/journal.pone.0112510] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 10/18/2014] [Indexed: 11/18/2022] Open
Abstract
Tropical regions are not well represented in glacier biology, yet many tropical glaciers are under threat of disappearance due to climate change. Here we report a novel biogenic aggregation at the terminus of a glacier in the Rwenzori Mountains, Uganda. The material was formed by uniseriate protonemal moss gemmae and protonema. Molecular analysis of five genetic markers determined the taxon as Ceratodon purpureus, a cosmopolitan species that is widespread in tropical to polar region. Given optimal growing temperatures of isolate is 20-30 °C, the cold glacier surface might seem unsuitable for this species. However, the cluster of protonema growth reached approximately 10 °C in daytime, suggesting that diurnal increase in temperature may contribute to the moss's ability to inhabit the glacier surface. The aggregation is also a habitat for microorganisms, and the disappearance of this glacier will lead to the loss of this unique ecosystem.
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Affiliation(s)
- Jun Uetake
- Transdisciplinary Research Integration Center, Minato-ku, Tokyo, Japan
- National Institute of Polar Research, Tachikawa, Tokyo, Japan
- * E-mail:
| | - Sota Tanaka
- Faculty of Science, Chiba University, Chiba, Chiba, Japan
| | - Kosuke Hara
- Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Yukiko Tanabe
- Institute for Advanced Study, Waseda University, Shinjuku-ku, Tokyo, Japan
| | - Denis Samyn
- Department of Mechanical Engineering, Nagaoka University of Technology, Nagaoka, Nigata, Japan
| | | | - Satoshi Imura
- Faculty of Science, Chiba University, Chiba, Chiba, Japan
| | - Shiro Kohshima
- Wildlife Research Center, Kyoto University, Kyoto, Kyoto, Japan
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Beal SA, Kelly MA, Stroup JS, Jackson BP, Lowell TV, Tapia PM. Natural and anthropogenic variations in atmospheric mercury deposition during the Holocene near Quelccaya Ice Cap, Peru. GLOBAL BIOGEOCHEMICAL CYCLES 2014; 28:437-450. [PMID: 30760944 PMCID: PMC6370314 DOI: 10.1002/2013gb004780] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Mercury (Hg) is a toxic metal that is transported globally through the atmosphere. The emission of Hg from mineral reservoirs and subsequent recycling in surface reservoirs (i.e., soil/biomass, ocean, and atmosphere) are fundamental to the modern global Hg cycle, yet past emissions from anthropogenic and natural sources are not fully constrained. We use a sediment core from Yanacocha, a headwater lake in southeastern Peru, to study the anthropogenic and natural controls on atmospheric Hg deposition during the Holocene. From 12.3 to 3.5 ka, Hg fluxes in the record are relatively constant (mean ± 1σ: 1.4 ± 0.6 μg m-2 a-1, n = 189). Past Hg deposition does not correlate with changes in regional temperature and precipitation, inferred from nearby paleoclimate records, or with most large volcanic events that occurred regionally, in the Andean Central Volcanic Zone (~300-400 km from Yanacocha), and globally. In B.C. 1450 (3.4 ka), Hg fluxes abruptly increased and reached the Holocene-maximum flux (6.7 μg m-2 a-1) in B.C. 1200, concurrent with a ~100-year peak in Fe and chalcophile metals (As, Ag, Tl) and the presence of framboidal pyrite. Continuously elevated Hg fluxes from B.C. 1200-500 suggest a protracted mining-dust source near Yanacocha that is identical in timing to documented pre-Incan cinnabar mining in central Peru. During Incan and Colonial time (A.D. 1450-1650), Hg deposition remains elevated relative to background levels but lower relative to other Hg records from sediment cores in central Peru, indicating a limited spatial extent of preindustrial Hg emissions. Hg fluxes from A.D. 1980 to 2011 (4.0 ± 1.0 μg m-2 a-1, n = 5) are 3.0 ± 1.5 times greater than pre-anthropogenic fluxes and are similar to modern fluxes documented in remote lakes around the world.
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Affiliation(s)
- Samuel A Beal
- Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire, USA
| | - Meredith A Kelly
- Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire, USA
| | - Justin S Stroup
- Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire, USA
| | - Brian P Jackson
- Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire, USA
| | - Thomas V Lowell
- Department of Geology, University of Cincinnati, Cincinnati, Ohio, USA
| | - Pedro M Tapia
- Department of Biological Sciences, Universidad Peruana Cayetano Heredia, Lima, Peru
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Frezzotti M, Orombelli G. Glaciers and ice sheets: current status and trends. RENDICONTI LINCEI 2013. [DOI: 10.1007/s12210-013-0255-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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35
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Lease RO, Ehlers TA. Incision into the Eastern Andean Plateau During Pliocene Cooling. Science 2013; 341:774-6. [DOI: 10.1126/science.1239132] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Richard O. Lease
- Department of Geosciences, University of Tübingen, Tübingen 72074, Germany
| | - Todd A. Ehlers
- Department of Geosciences, University of Tübingen, Tübingen 72074, Germany
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