@article {bianchette_machine_2023,
	title = {Machine learning based anomaly detection for sedimentological data: Application to a Holocene multi-proxy paleoenvironmental reconstruction from Laguna Boquita, Jalisco, Mexico},
	journal = {Marine Geology},
	volume = {464},
	year = {2023},
	month = {08/2023},
	pages = {107125},
	abstract = {Paleoenvironmental reconstructions are critical to determine past climatological and hydrological conditions, such as sea-level rise (SLR) and extreme events including hurricanes and tsunamis. While established quantitative methods, such as principal components analysis and discriminant analysis, have effectively aided reconstructions by demarcating stratigraphic zones, they suffer from limitations due to the underlying assumptions (linearity, normality). Here, we introduce the machine learning technique anomaly detection for sedimentological reconstructions, capable of objectively pinpointing events (anomalies) in sediment cores. We tested this technique on five sediment cores extracted from Laguna Boquita, located along the Pacific coast of Mexico. Each core was subjected to high resolution loss-on-ignition, while the most representative core (core 1) was deemed the training core and scanned with a handheld XRF unit. In general, the sediment cores were dominated by thick units of peat and/or clay, and most cores contained sand layers. This reconstruction represents many environmental settings, ranging from a sandy terrestrial environment (\~{}6830-~\~{}~6370~cal~yr BP), organic-rich wetland (\~{}6370-~\~{}~5170~cal~yr BP), and clastic-rich backbarrier lagoon (\~{}5170~cal~yr BP to present). The anomaly detection technique proved effective in marking many events, including marine transgression, evidence of SLR, transitions separating dominant depositional environments, and, perhaps most notably, a faded blue clay layer with minimal LOI variability that may represent a shift in backbarrier water level. The anomaly detection also registered anomalies when events were not visually distinct nor present in the LOI datasets (false positives), which represent sediment core sections that require further investigation with multiple proxies. However, anomaly detection failed to register anomalies in certain core sections that should have registered as events due to their distinct nature. Future efforts will look to improve anomaly detection by choosing different train cores and adding additional proxy datasets.},
	keywords = {Loss-on-ignition, Machine learning, Paleoclimate, peat, Radiocarbon dating, x-ray fluorescence},
	issn = {0025-3227},
	doi = {10.1016/j.margeo.2023.107125},
	url = {https://www.sciencedirect.com/science/article/pii/S0025322723001378},
	author = {Bianchette, Thomas A. and Pandey, Vijitashwa and Mollan, Calahan and Hall, Sawyer and McCloskey, Terrence A. and Liu, Kam-biu}
}
@article {winkler_more_2023,
	title = {More Frequent Hurricane Passage Across the Bahamian Archipelago During the Little Ice Age},
	journal = {Paleoceanography and Paleoclimatology},
	volume = {38},
	number = {11},
	year = {2023},
	note = {_eprint: https://onlinelibrary.wiley.com/doi/pdf/10.1029/2023PA004623},
	month = {11/2023},
	pages = {e2023PA004623},
	abstract = {The year 2020 Common Era (CE) experienced the highest number of named tropical cyclones in the Atlantic Ocean since 1850 CE, but the short instrumental record makes it challenging to assess if this level of activity is statistically meaningful. Here, we present two near-annually resolved hurricane reconstructions from sediment archived in two blue holes located only 300 m apart on the northern margin of Grand Bahama. These two blue holes provide a replicated signal of hurricanes passing within a 50{\textendash}100 km radius over the last 1,800 years, and the long-term reconstructions document multiple 50-to-150-year intervals when hurricane frequency was significantly higher than it has been over the last 100 years. These two records were first merged into a single stack, and then compiled with five other high-resolution reconstructions from across the Bahamian Archipelago to form a single 1500-year record of Bahamian hurricane frequency. This new Bahamian Compilation documents more hurricanes passing \~{}75{\textdegree}W from 21{\textdegree}N to 26{\textdegree}N during the Little Ice Age (LIA; 1300{\textendash}1850 CE) relative to the prior millennium and the last 170 years. The US Eastern Seaboard also experienced heightened hurricane activity during the LIA, whereas the Gulf of Mexico and Southern Caribbean were inactive. This suggests that despite a globally cooler climate, regional climate conditions during the LIA remained favorable for cyclogenesis and intensification along certain Atlantic hurricane pathways. Perhaps heightened Sahel rainfall during the LIA indicates an increase in African Easterly waves, which in turn possibly seeded more tropical cyclones in the Atlantic Main Development Region.},
	keywords = {Bahamas, Carbonate, common era, hurricanes, Paleoclimate, sedimentology},
	issn = {2572-4525},
	doi = {10.1029/2023PA004623},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1029/2023PA004623},
	author = {Winkler, T. S. and van Hengstum, P. J. and Donnelly, J. P. and Wallace, E. J. and Albury, N. A. and D{\textquoteright}Entremont, N. and Hawkes, A. D. and Maio, C. V. and Roberts, J. and Sullivan, R. M. and Woodruff, J. D.}
}
@article {thatcher_iberian_2022,
	title = {Iberian hydroclimate variability and the Azores High during the last 1200 years: evidence from proxy records and climate model simulations},
	journal = {Climate Dynamics},
	year = {2022},
	month = {08/2022},
	pages = {1{\textendash}23},
	abstract = {The state of the atmospheric circulation and the associated hydroclimate in the North Atlantic during the last millennium remain the subject of considerable debate in both proxy- and model-based studies. Of particular interest in the Iberian region is the Azores High (AH) system, the southern node of the North Atlantic Oscillation (NAO), an atmospheric dipole closely tied to regional hydroclimate. Hydroclimate-sensitive proxy reconstructions from this region offer some insights into atmospheric dynamics, but large spatiotemporal gaps in these data inhibit a robust evaluation of hydroclimate variability. In this study, we present a continuous, sub-decadally-resolved composite stalagmite carbon isotopic record from three partially overlapping stalagmites from Buraca Gloriosa (BG) cave, western Portugal, situated within the center of the AH, that preserves evidence of regional hydroclimate variability from approximately 800 CE to the present. Chronologies are derived from U/Th dating and annual laminae. Stalagmite carbon isotopic values primarily reflect the amount of effective moisture and reveal generally dry conditions during the Medieval Climate Anomaly (MCA; 850{\textendash}1250 CE) and Modern Climate/Industrial Era (1850 CE-present), and wetter conditions during the Little Ice Age (LIA; 1400{\textendash}1850 CE). Multidecadal to centennial variability in the BG record and state-of-the-art last millennium climate model simulations show considerable coherence with precipitation-sensitive records from Spain and Morocco that, like BG, are strongly influenced by the intensity, size, and location of the AH. Model-proxy synthesis suggests that western Portugal was persistently dry during much of the MCA consistent with other NAO reconstructions; however, even considering age uncertainties, the apparent timing in the transition from a relatively dry MCA to a wetter LIA is spatially variable and confirms the non-stationary behavior of the AH system indicated by model output.},
	keywords = {Azores High, Hydroclimate, last millennium, Last Millennium Ensemble, Paleoclimate, Stalagmite},
	doi = {10.1007/s00382-022-06427-6},
	url = {https://app.dimensions.ai/details/publication/pub.1150271437},
	author = {Thatcher, Diana L. and Wanamaker, A. D. and Denniston, R. F. and Ummenhofer, C. C. and Asmerom, Y. and Polyak, V. J. and Cresswell-Clay, N. and Hasiuk, F. and Haws, J. and Gillikin, D. P.}
}
@article {2703,
	title = {Comparing and improving methods for reconstructing peatland water-table depth from testate amoebae},
	journal = {The Holocene},
	volume = {29},
	year = {2019},
	month = {Jan-08-2020},
	pages = {1350 - 1361},
	abstract = {Proxies that use changes in the composition of ecological communities to reconstruct temporal changes in an environmental covariate are commonly used in paleoclimatology and paleolimnology. Existing methods, such as weighted averaging and modern analog technique, relate compositional data to the covariate in very simple ways, and different methods are seldom compared systematically. We present a new Bayesian model that better represents the underlying data and the complexity in the relationships between species{\textquoteright} abundances and a paleoenvironmental covariate. Using testate amoeba{\textendash}based reconstructions of water-table depth as a test case, we systematically compare new and existing models in a cross-validation experiment on a large training dataset from North America. We then apply the different models to a new 7500-year record of testate amoeba assemblages from Caribou Bog in Maine and compare the resulting water-table depth reconstructions. We find that Bayesian models represent an improvement over existing methods in three key ways: more complete use of the underlying compositional data, full and meaningful treatment of uncertainty, and clear paths toward methodological improvements. Furthermore, we highlight how developing and systematically comparing methods lead to an improved understanding of the proxy system. This paper focuses on testate amoebae and water-table depth, but the framework and ideas are widely applicable to other proxies based on compositional data.},
	keywords = {Bayesian statistics, compositional data, Holocene, hydrology, North America, Northeast United States, Paleoclimate, peatlands, statistical methods, testate amoebae},
	issn = {0959-6836},
	doi = {10.1177/0959683619846969},
	url = {https://journals.sagepub.com/doi/10.1177/0959683619846969},
	author = {Nolan, Connor and Tipton, John and Booth, Robert K and Hooten, Mevin B and Jackson, Stephen T}
}
@article {2677,
	title = {Coupled ocean and atmospheric changes during Greenland stadial 1 in southwestern Europe},
	journal = {Quaternary Science Reviews},
	volume = {212},
	year = {2019},
	month = {Jan-05-2019},
	pages = {108 - 120},
	abstract = {Paleoclimate reconstructions suggest that the complex variability within the Greenland stadial 1 (GS-1) over western Europe was governed by coupled ocean and atmospheric changes. However, few works from the North Atlantic mid-latitudes document both the GS-1 onset and its termination, which are often considered as single abrupt transition events. Here, we present a direct comparison between marine (alkenone-based sea surface temperatures) and terrestrial (pollen) data, at very high resolution (28 years mean), from the southwestern Iberian shelf record D13882. Our results reveal a rather complex climatic period with internally changing conditions. The GS-1 onset (GS-1a: 12890-12720 yr BP) is marked by a progressive cooling and drying; GS-1b (12720-12390 yr BP) is the coldest and driest phase; GS-1c (12390-12030 yr BP) is marked by a progressive warming and increase in moisture conditions; GS-1 termination (GS-1d: 12030-11770 yr BP) is marked by rapid switches between cool wet, cold dry and cool wet conditions. Although hydroclimate response was very unsteady throughout the GS-1 and in particular during its termination phase, the persistence of an open temperate and Mediterranean forest in southwestern Iberia during the entire episode suggests that at least some moisture was delivered via the Westerlies. We propose coupled ocean and atmospheric mechanisms to reproduce these scenaria. Changes in the strength of the Atlantic Meridional Overturning Circulation (AMOC) as well as variations in the North Atlantic sea-ice growth have favoured the displacement of the polar jet stream{\textquoteright}s latitudinal position and contributed to a complex spatial pattern and strength of the Westerlies across western Europe.},
	keywords = {Climate variability, Greenland stadial, Iberian margin, Jet stream, Moisture availability, North Atlantic, Paleoclimate, Westerlies, Younger Dryas Complex},
	issn = {02773791},
	doi = {10.1016/j.quascirev.2019.03.033},
	url = {https://www.researchgate.net/publication/332292599_Coupled_ocean_and_atmospheric_changes_during_Greenland_stadial_1_in_southwestern_Europe},
	author = {Naughton, F. and Costas, S. and Gomes, S.D. and Desprat, S. and Rodrigues, T. and Sanchez Go{\~n}i, M.F. and Renssen, H. and Trigo, R. and Bronk-Ramsey, C. and Oliveira, D. and Salgueiro, E. and Voelker, A.H.L. and Abrantes, F.}
}
@article {2785,
	title = {Lake-level variability in Salar de Coipasa, Bolivia during the past \~{}40,000 yrAbstract},
	journal = {Quaternary Research},
	volume = {91},
	year = {2019},
	month = {Jan-03-2019},
	pages = {881 - 891},
	abstract = {Various paleoclimatic records have been used to reconstruct the hydrologic history of the Altiplano, relating this history to past variability of the South American summer monsoon. Prior studies of the southern Altiplano, the location of the world{\textquoteright}s largest salt flat, the Salar de Uyuni, and its neighbor, the Salar de Coipasa, generally agree in their reconstructions of the climate history of the past \~{}24 ka. Some studies, however, have highly divergent climatic records and interpretations of earlier periods. In this study, lake-level variation was reconstructed from a \~{}14-m-long sediment core from the Salar de Coipasa. These sediments span the last \~{}40 ka. Lacustrine sediment accumulation was apparently continuous in the basin from \~{}40 to 6 ka, with dry or very shallow conditions afterward. The fossil diatom stratigraphy and geochemical data (δ13C, δ15N, \%Ca, C/N) indicate fluctuations in lake level from shallow to moderately deep, with the deepest conditions correlative with the Heinrich-1 and Younger Dryas events. The stratigraphy shows a continuous lake of variable depth and salinity during the last glacial maximum and latter stages of Marine Oxygen Isotope Stage 3 and is consistent with environmental inferences and the original chronology of a drill core from Salar de Uyuni.},
	keywords = {Altiplano, Andes, Paleoclimate, paleohydrology, Paleolake, South America},
	issn = {0033-5894},
	doi = {10.1017/qua.2018.108},
	url = {https://www.cambridge.org/core/product/identifier/S0033589418001084/type/journal_article},
	author = {Nunnery, J. Andrew and Fritz, Sherilyn C. and Baker, Paul A. and Salenbien, Wout}
}
@article {2857,
	title = {Temperature-controlled tundra fire severity and frequency during the last millennium in the Yukon-Kuskokwim Delta, Alaska},
	journal = {The Holocene},
	volume = {29},
	year = {2019},
	month = {Jan-07-2019},
	pages = {1223 - 1233},
	abstract = {Wildfire is an important disturbance to Arctic tundra ecosystems. In the coming decades, tundra fire frequency, intensity, and extent are projected to increase because of anthropogenic climate change. To more accurately predict the effects of climate change on tundra fire regimes, it is critical to have detailed knowledge of the natural frequency and extent of past wildfires and how they responded to past climate variability. We present analyses of fire frequency and temperature from a lake sediment core from the Yukon-Kuskokwim (YK) Delta. Our ca. 1000 macroscopic charcoal record shows more frequent but possibly less severe tundra fires during the first half of the last millennium, whereas less frequent, possibly more severe fires characterize the latter half. Our temperature reconstruction, based on distributional changes of branched glycerol dialkyl glycerol tetraethers (brGDGTs), shows slightly warmer conditions from ca. AD 1000 to 1500, and cooler conditions thereafter (ca. AD 1500 to 2000), suggesting that fire frequency increases when climate is relatively warmer in this region. When wildfires occur more frequently, fire severity may decrease because of limited biomass (fuel source) accumulating between fires. The data suggest that tundra ecosystems are highly sensitive to climate change, and that a warmer climate, which is predicted to develop in the near future, will result in more frequent tundra wildfires.},
	keywords = {alaska, Arctic, charcoal, glycerol dialkyl glycerol tetraethers (GDGTs), late-holocene, Paleoclimate, Paleofire},
	issn = {0959-6836},
	doi = {10.1177/0959683619838036},
	url = {http://journals.sagepub.com/doi/10.1177/0959683619838036},
	author = {Sae-Lim, Jarunetr and Russell, James M and Vachula, Richard S and Holmes, Robert M and Mann, Paul J and Schade, John D and Natali, Susan M}
}
@article {2844,
	title = {A 7000-year history of coastal environmental changes from Mexico{\textquoteright}s Pacific coast: A multi-proxy record from Laguna Mitla, Guerrero},
	journal = {The Holocene},
	volume = {27},
	year = {2017},
	month = {Sep-08-2017},
	pages = {1214 - 1226},
	abstract = {The lack of multi-millennial multi-proxy paleoenvironmental reconstructions from Mexico{\textquoteright}s Pacific coast has limited our understanding of the regional response to climate change and sea-level rise. A 479-cm core covering the last 6900 years was extracted from Laguna Mitla in the state of Guerrero on Mexico{\textquoteright}s Pacific coast. Beginning as a Rhizophora-dominated salt pan ~6900 yr BP, at ~6500 yr BP, the site transitioned to a mangrove swamp dominated by Laguncularia, which lasted about 300 years. The beach barrier formed from ~6200 to 5200 yr BP, during which time, the site existed as an intermittently sheltered bay, the result of large, rapid changes in wave energy associated with the shifting barrier location and changes in stability. After the beach barrier was stabilized at ~5200 yr BP, water level at the coring site became a function of precipitation rather than sea level. Since that time, deposition has alternated between peat, laid down in a mangrove swamp, and clay intervals characterized by high concentrations of titanium and a predominantly regional pollen signal, representing open-water lagoon phases. Seven periods of increased water level, varying in duration, occurred during the backbarrier period, with El Ni{\~n}o-Southern Oscillation (ENSO) likely the main climatic mechanism causing these periodic shifts in the paleo-precipitation levels. We suggest that the deepest water levels detected over the last ~3200 years correlate with periods of increased ENSO activity. The spatial distribution of tropical cyclone rainfall, which represents a significant percentage of total annual precipitation along Mexico{\textquoteright}s Pacific coast, may explain the inconsistencies between our record and paleoclimatic records from Mexico{\textquoteright}s interior, but more work is needed to test this hypothesis.},
	keywords = {El Nino-Southern Oscillation, Laguna Mitla, mangroves, Pacific coast of Mexico, Paleoclimate, paleoenvironmental reconstruction, pollen, Sediment, tropical cyclones, x-ray fluorescence},
	issn = {0959-6836},
	doi = {10.1177/0959683616687379},
	url = {http://journals.sagepub.com/doi/10.1177/0959683616687379},
	author = {Bianchette, Thomas A and McCloskey, Terrence A and Liu, Kam-biu}
}
@article {2529,
	title = {Holocene climate and environmental history of East Greenland inferred from lake sediments},
	journal = {Journal of Paleolimnology},
	volume = {57},
	year = {2017},
	month = {Jan-04-2017},
	pages = {321 - 341},
	abstract = {Prediction of future Arctic climate and environmental changes, as well as associated ice-sheet behavior, requires placing present-day warming and reduced ice extent into a long-term context. Here we present a record of Holocene climate and glacier fluctuations inferred from the paleolimnology of small lakes near Istorvet ice cap in East Greenland. Calibrated radiocarbon dates of organic remains indicate deglaciation of the region before ~10,500 years BP, after which time the ice cap receded rapidly to a position similar to or less extensive than present, and lake sediments shifted from glacio-lacustrine clay to relatively organic-rich gyttja. The lack of glacio-lacustrine sediments throughout most of the record suggests that the ice cap was similar to or smaller than present throughout most of the Holocene. This restricted ice extent suggests that climate was similar to or warmer than present, in keeping with other records from Greenland that indicate a warm early and middle Holocene. Middle Holocene magnetic susceptibility oscillations, with a ~200-year frequency in one of the lakes, may relate to solar influence on local catchment processes. Following thousands of years of restricted extent, Istorvet ice cap advanced to within 365 m of its late Holocene limit at ~AD 1150. Variability in the timing of glacial and climate fluctuations, as well as of sediment organic content changes among East Greenland lacustrine records, may be a consequence of local factors, such as elevation, continentality, water depth, turbidity, and seabirds, and highlights the need for a detailed spatial array of datasets to address questions about Holocene climate change.},
	keywords = {De Vries cycle, Glacially fed lakes, Greenland, Holocene, Paleoclimate},
	issn = {0921-2728},
	doi = {10.1007/s10933-017-9951-5},
	url = {http://link.springer.com/10.1007/s10933-017-9951-5},
	author = {Lusas, Amanda R. and Hall, Brenda L. and Lowell, Thomas V. and Kelly, Meredith A. and Bennike, Ole and Levy, Laura B. and Honsaker, William}
}
@article {2786,
	title = {Younger-Dryas cooling and sea-ice feedbacks were prominent features of the Pleistocene-Holocene transition in Arctic Alaska},
	journal = {Quaternary Science Reviews},
	volume = {169},
	year = {2017},
	month = {Jan-08-2017},
	pages = {330 - 343},
	abstract = {Declining sea-ice extent is currently amplifying climate warming in the Arctic. Instrumental records at high latitudes are too short-term to provide sufficient historical context for these trends, so paleoclimate archives are needed to better understand the functioning of the sea ice-albedo feedback. Here we use the oxygen isotope values of wood cellulose in living and sub-fossil willow shrubs (δ18Owc) (Salix spp.) that have been radiocarbon-dated (14C) to produce a multi-millennial record of climatic change on Alaska{\textquoteright}s North Slope during the Pleistocene-Holocene transition (13,500{\textendash}7500 calibrated 14C years before present; 13.5{\textendash}7.5 ka). We first analyzed the spatial and temporal patterns of δ18Owc in living willows growing at upland sites and found that over the last 30 years δ18Owc values in individual growth rings correlate with local summer temperature and inter-annual variations in summer sea-ice extent. Deglacial δ18Owc values from 145 samples of subfossil willows clearly record the Aller{\o}d warm period (\~{}13.2 ka), the Younger Dryas cold period (12.9{\textendash}11.7 ka), and the Holocene Thermal Maximum (11.7{\textendash}9.0 ka). The magnitudes of isotopic changes over these rapid climate oscillations were \~{}4.5{\textperthousand}, which is about 60\% of the differences in δ18Owc between those willows growing during the last glacial period and today. Modeling of isotope-precipitation relationships based on Rayleigh distillation processes suggests that during the Younger Dryas these large shifts in δ18Owc values were caused by interactions between local temperature and changes in evaporative moisture sources, the latter controlled by sea ice extent in the Arctic Ocean and Bering Sea. Based on these results and on the effects that sea-ice have on climate today, we infer that ocean-derived feedbacks amplified temperature changes and enhanced precipitation in coastal regions of Arctic Alaska during warm times in the past. Today, isotope values in willows on the North Slope of Alaska are similar to those growing during the warmest times of the Pleistocene-Holocene transition, which were times of widespread permafrost thaw and striking ecological changes.},
	keywords = {alaska, Arctic, Bering Strait, Climate change, dendrochronology, north pacific, oxygen isotopes, Paleoclimate, Sea ice, Younger Dryas},
	issn = {02773791},
	doi = {10.1016/j.quascirev.2017.05.012},
	url = {https://linkinghub.elsevier.com/retrieve/pii/S0277379117301713},
	author = {Gaglioti, Benjamin V. and Mann, Daniel H. and Wooller, Matthew J. and Jones, Benjamin M. and Wiles, Gregory C. and Groves, Pamela and Kunz, Michael L. and Baughman, Carson A. and Reanier, Richard E.}
}
@article { ISI:000346894800004,
	title = {Holocene paleoclimatic variation in the Schirmacher Oasis, East Antarctica: A mineral magnetic approach}},
	journal = {POLAR SCIENCE},
	volume = {8},
	number = {{4}},
	year = {2014},
	month = {DEC},
	pages = {357-369},
	type = {Article},
	abstract = {An analysis of remanent magnetism and radiocarbon ages in the dry lacustrine/sediment fills of the Schirmacher Oasis (SO) in East Antarctica was conducted to reconstruct past climatic condition. The statistically run mineral magnetic data on paleontological statistics software package (multivariate cluster analysis) placed on accelerator mass spectrometer radiocarbon chronology of the three sediment sections, trace 6 phases of climatic fluctuation between 13 and 3 ka, (Phases 1, 3 and 5 represent cold periods while Phases 2, 4, and 6 represent warm periods). One short warm period (Phase 2, ca. 12.5 ka) occurred in the late Pleistocene, and two marked warm periods (Phase 4, 11-8.7 ka; Phase 6, 4.4-3 ka) occurred in the Holocene. High magnetic susceptibility (chi), saturation isothermal remanent magnetism (SIRM), and soft isothermal remanent magnetism (soft IRM) values correspond to colder periods and low values reflect comparatively warmer lacustrine phases. Holocene Optima (Phase 4) and Mid Holocene Hypsithermal (Phase 6) are distinguished by decreased values of concentrations dependent parameters. Remanence is preserved in the low-coercive minerals. Heavy metals in the sediments include, Fe, Rb, Zn, Mo, Co, Pb, Mn, Cu, and As in order of decreasing abundance. (C) 2014 Elsevier B.V. and NIPR. All rights reserved.},
	keywords = {Holocene, Lacustrine sediments, Mineral remanent magnetism, Paleoclimate, Schirmacher Oasis},
	issn = {1873-9652},
	doi = {10.1016/j.polar.2014.06.001},
	author = {Phartiyal, Binita}
}
@article {1946,
	title = {Postglacial climate reconstruction based on compound-specific D/H ratios of fatty acids from Blood Pond, New England},
	journal = {Geochemistry Geophysics Geosystems},
	volume = {7},
	year = {2006},
	note = {031uaTimes Cited:32
Cited References Count:43
},
	month = {Mar 28},
	abstract = {We determined hydrogen isotope ratios of individual fatty acids in a sediment core from Blood Pond, Massachusetts, USA, in order to reconstruct climate changes during the past 15 kyr. In addition to palmitic acid (C-16 n-acid), which has been shown to record lake water D/H ratios, our surface sediments and down core data indicate that behenic acid (C-22 n-acid), produced mainly by aquatic macrophytes, is also effective for capturing past environmental change. Calibration using surface sediments from two transects across eastern North America indicates that behenic acid records delta D variation of lake water. Down core variations in delta D values of behenic acid and pollen taxa are consistent with the known climate change history of New England. By evaluating the hypothesis that D/H fractionations of long chain even numbered fatty acids (C-24-C-32 n-acids) relative to lake water provide independent estimates of relative humidity during the growing season, we find that differences between lake-level records and isotopically inferred humidity estimates may provide useful insight into seasonal aspects of the hydrologic cycle. Combined analyses of D/H of short and long chain fatty acids from lake sediment cores thus allow reconstructions of both past temperature and growing season relative humidity. Comparison of delta D records from two lakes in New England provides critical information on regional climate variation and abrupt climate change, such as the 8.2 ka event.},
	keywords = {atmospheric processes : paleoclimatology, eastern north-america, fatty acids, geochemistry : organic and biogenic geochemistry, geochemistry : stable isotope geochemistry, Holocene, hydrogen isotope, hydrogen isotope ratios, lacustrine organic-matter, lake-sediments, Paleoclimate, record, Stable isotopes, united-states, vegetation history, younger-dryas},
	isbn = {1525-2027},
	doi = {10.1029/2005GC001076},
	author = {Hou, J. Z. and Huang, Y. S. and Wang, Y. and Shuman, B. and Oswald, W. W. and Faison, E. and Foster, D. R.}
}
@article {895,
	title = {A continuous high-resolution record of late Pleistocene climate variability from the Estacia basin, New Mexico},
	journal = {Geological Society of America Bulletin},
	volume = {112},
	year = {2000},
	note = {id: 239},
	pages = {1444-1458},
	abstract = {Lake sediments that accumulated in the Estancia basin, central New Mexico, provide a detailed record of submillennial latest Pleistocene climatic oscillations. Sedimentologic, biologic, and geochemical proxies for changes in salinity and lake level were used to identify episodes of wet and dry climate that occurred between 24 and 12 k.y. B.P., as dated by 14C by means of accelerator mass spectrometry from shoreline and basin-center deposits. These dates determine the timing and duration of the episodes of wet and dry climate. The lake expanded and contracted repeatedly during the last glacial maximum and fluctuated near its highest elevation several times during the interval ca. 20 to 15 k.y. B.P. A pronounced lowstand lasting \~{}1 k.y. occurred between ca. 15 and 14 k.y. B.P., followed by two more highstands of the lake between ca. 14 and 12.5 k.y. B.P. Desiccation of the perennial lake after 12 k.y. B.P. was followed by a final, poorly dated highstand at ca. 10 k.y. B.P. The record of lake-level fluctuations from the Estancia basin provides a high-resolution record of changes in water budget in a basin, the comparatively simple physiography and hydrogeology of which ensured a direct response to the strong climatic fluctuations that occurred during the last glacial maximum and termination. },
	keywords = {Lacustrine sediments, Last glacial maximum, ostracodes, Paleoclimate, trace metals},
	doi = {10.1130/0016-7606(2000)112<1444:ACHRRO>2.0.CO;2},
	author = {Allen, B. D. and Anderson, R. Y.}
}
@article {2387,
	title = {Biogenic Silica in Lake Baikal Sediments - Results from 1990-1992 American Cores},
	journal = {Journal of Great Lakes Research},
	volume = {20},
	year = {1994},
	note = {Px453Times Cited:46
Cited References Count:20
},
	month = {1994},
	pages = {751-760},
	abstract = {The Lake Baikal Paleoclimate Project is a joint Russian-American program established to study the paleoclimate of Central Asia. During three summer field seasons, duplicate Russian and American coves were taken at a number of sites in different sedimentary environments in the lake. Eight cores returned to the U.S. were quantitatively analyzed for biogenic silica using a single-step 5-hour alkaline leach, followed by dissolved silicon analysis by inductively-coupled-plasma atomic-emission spectroscopy. Sediments of Holocene age in these cores have biogenic silica maxima that range from about 15 to 80 percent. An underlying zone in each core with low biogenic-silica concentrations (0 to 5 percent) dates from the last glacial maximum. The transition from the last glaciation to the present interglaciation, recorded by biogenic silica, began about 13,000 years ago. Biogenic silica profiles from these cores appear to be a good measure of past diatom productivity and a useful basis for paleoclimatic interpretations.},
	keywords = {accumulation, Holocene, Lake Baikal, marine-sediments, opal, Paleoclimate, sediments, silica},
	isbn = {0380-1330},
	author = {Carter, S. J. and Colman, S. M.}
}
