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• 21. [Article] Silicic acid biogeochemistry in the Gulf of California: Insights from sedimentary Si isotopes

  This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: [link to journal].

  Citation × Citation Citation Abstract Copy Title: Silicic acid biogeochemistry in the Gulf of California: Insights from sedimentary Si isotopes Author: McClymont, Erin L., Ganeshram, Raja S., Thunell, Robert, Prahl, Fredrick, Pedersen, Thomas F., Pichevin, Laetitia, Reynolds, Ben C. This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: [link to journal]. Title: Silicic acid biogeochemistry in the Gulf of California: Insights from sedimentary Si isotopes Author: McClymont, Erin L., Ganeshram, Raja S., Thunell, Robert, Prahl, Fredrick, Pedersen, Thomas F., Pichevin, Laetitia, Reynolds, Ben C. This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: [link to journal]. Close

• 22. [Article] Glacial to holocene watermass and continental weathering reconstructions from the Southeast Pacific

  Sediments of the central Chile margin record changes in ocean circulation and continental erosion associated with large–scale climate change. Here Antarctic– influenced Southern Ocean currents flow equatorward, ...

  Citation × Citation Citation Abstract Copy Title: Glacial to holocene watermass and continental weathering reconstructions from the Southeast Pacific Author: Muratli, Jesse M. Sediments of the central Chile margin record changes in ocean circulation and continental erosion associated with large–scale climate change. Here Antarctic– influenced Southern Ocean currents flow equatorward, forming a link between the high– and low–latitude oceans. Part of this link, Antarctic Intermediate Water, is an important conduit that ventilates South Pacific subsurface and mid–depth waters. Differential weathering of the two parallel mountain ranges of Chile has been attributed to latitudinal shifts in the position of the southern westerly wind belt, with an equatorward shift increasing Coast Range rainfall and weathering rates. An increase in Coast Range weathering relative to Andean weathering has been proposed to reduce the delivery of iron to the marginal ocean, with implications for productivity in the Fe– limited Southern Ocean–derived waters. Sediments from three drill sites along the Chile margin (36°S–41°S, water depths ~500–1000 m) monitor changes in the extent and distribution of surface and subsurface ocean currents, as well as provenance of continental weathering products. Concentrations of the redox–sensitive metals Mn and Re in the sediments are controlled by bottom water oxygen. Decreasing concentrations of Mn and increased levels of Re relative to glacial–age concentrations suggest a deglacial poleward retreat of Antarctic Intermediate Water and subsequent expansion of low–oxygen water masses sourced from low latitudes. A suite of elements defines lithogenic contributions to the sediments, and a river sediment dataset provides a link to possible source regions on the continent. Rivers draining the Chilean Coast Range have similar Al concentrations to Andean rivers, but are poorer (relative to Al) in Ca, Mg, and Sr. Although Andean rocks have been hypothesized to be relatively iron–rich, levels of Fe/Al and Ti/Al are indistinguishable among river types. Marine sediments show reduced values of Mg/Al relative to glacial levels after deglaciation, suggesting a switch to a Coast Range source of material. This analysis implies that at latitudes south of 36°S ice sheet retreat after the glacial period caused an overall decrease in the rate of Andean weathering, which overwhelmed any signal of decreased Coast Range weathering driven by the poleward retreat of the westerly winds. In southern Chile (41°S) increased Holocene Ti/Al is interpreted as a switch after deglaciation to a Coast Range source rich in titanium. While weathering patterns, driven mainly by ice sheet changes, are not likely to change in a warming planet, recent observational trends in ocean circulation and intermediate water oxygen content suggest a future expansion of oxygen–minimum zones. Title: Glacial to holocene watermass and continental weathering reconstructions from the Southeast Pacific Author: Muratli, Jesse M. Sediments of the central Chile margin record changes in ocean circulation and continental erosion associated with large–scale climate change. Here Antarctic– influenced Southern Ocean currents flow equatorward, forming a link between the high– and low–latitude oceans. Part of this link, Antarctic Intermediate Water, is an important conduit that ventilates South Pacific subsurface and mid–depth waters. Differential weathering of the two parallel mountain ranges of Chile has been attributed to latitudinal shifts in the position of the southern westerly wind belt, with an equatorward shift increasing Coast Range rainfall and weathering rates. An increase in Coast Range weathering relative to Andean weathering has been proposed to reduce the delivery of iron to the marginal ocean, with implications for productivity in the Fe– limited Southern Ocean–derived waters. Sediments from three drill sites along the Chile margin (36°S–41°S, water depths ~500–1000 m) monitor changes in the extent and distribution of surface and subsurface ocean currents, as well as provenance of continental weathering products. Concentrations of the redox–sensitive metals Mn and Re in the sediments are controlled by bottom water oxygen. Decreasing concentrations of Mn and increased levels of Re relative to glacial–age concentrations suggest a deglacial poleward retreat of Antarctic Intermediate Water and subsequent expansion of low–oxygen water masses sourced from low latitudes. A suite of elements defines lithogenic contributions to the sediments, and a river sediment dataset provides a link to possible source regions on the continent. Rivers draining the Chilean Coast Range have similar Al concentrations to Andean rivers, but are poorer (relative to Al) in Ca, Mg, and Sr. Although Andean rocks have been hypothesized to be relatively iron–rich, levels of Fe/Al and Ti/Al are indistinguishable among river types. Marine sediments show reduced values of Mg/Al relative to glacial levels after deglaciation, suggesting a switch to a Coast Range source of material. This analysis implies that at latitudes south of 36°S ice sheet retreat after the glacial period caused an overall decrease in the rate of Andean weathering, which overwhelmed any signal of decreased Coast Range weathering driven by the poleward retreat of the westerly winds. In southern Chile (41°S) increased Holocene Ti/Al is interpreted as a switch after deglaciation to a Coast Range source rich in titanium. While weathering patterns, driven mainly by ice sheet changes, are not likely to change in a warming planet, recent observational trends in ocean circulation and intermediate water oxygen content suggest a future expansion of oxygen–minimum zones. Close

• 23. [Article] Cosmogenic ¹°Be chronology for the last deglaciation of the southern Scandinavian Ice Sheet

  The goal of this dissertation is to develop a chronology of the retreat of the southern margin of the Scandinavian Ice Sheet (SIS) during the late Pleistocene using surface exposure dating with cosmogenic ...

  Citation × Citation Citation Abstract Copy Title: Cosmogenic ¹°Be chronology for the last deglaciation of the southern Scandinavian Ice Sheet Author: Rinterknecht, Vincent R. The goal of this dissertation is to develop a chronology of the retreat of the southern margin of the Scandinavian Ice Sheet (SIS) during the late Pleistocene using surface exposure dating with cosmogenic 10Be. A sequence of seven prominent moraines in northeastern Europe (the Leszno Moraine, the Pomeranian Moraine, the Middle Lithuanian Moraine, the North Lithuanian Moraine, the P andivere Moraine, the Palivere Moraine, and the Salpausselka I Moraine) indicates a potential millennialscale record of climate variability. However, there are no direct dating constraints on the timing of this ice sheet retreat. Surface exposure dating using cosmogenic nuclide elements produced by secondary high-energy particles in the upper part of the lithosphere allows for direct dating of moraines deposited by the SIS. Cosmogenic 10Be concentrations were measured in quartz sampled from erratic boulders deposited on top of the moraines. The SIS margin withdrew from its maximum extent at 17,9 ± 2,4 10Be ka, which is correlative to the end of the Last Glacial Maximum period (23,0 to 19,0 ka). Following a recessional period, the ice readvanced to the Pomeranian Moraine. Deglaciation from this moraine is dated at 14,1 ± 1,8 10Be ka, and subsequent deglaciation is marked by the Middle Lithuanian Moraine (13,1 ± 1,7 "Be ka), the North Lithuanian Moraine (13,1 ± 1,7 10Be ka), the Pandivere Moraine (13,0 ± 1,1 10Be ka), the Palivere Moraine (10.0 ± 1,3 10Be ka), and the Salpausselka I Moraine (12,5 ± 1,5 10Be ka). This new chronology is compared to abrupt climate variability recorded in the North Atlantic region during the late Pleistocene. Paleo air temperatures recorded from the GISP2 ice core and paleo sea surface temperatures recorded from the North Atlantic region display warmings at the end of the Last Glacial Maximum period, during the Balling-Allerod interstadial, and at the end of the Younger Dryas stadial. These records also display abrupt coolings during the Oldest Dryas and the Younger Dryas stadials. Based on the 10Be chronology, the margin of the SIS responded to climate changes that occurred in the North Atlantic region. This new chronology contributes the first direct evidence of climate forcing on the southern margin of the SIS. Title: Cosmogenic ¹°Be chronology for the last deglaciation of the southern Scandinavian Ice Sheet Author: Rinterknecht, Vincent R. The goal of this dissertation is to develop a chronology of the retreat of the southern margin of the Scandinavian Ice Sheet (SIS) during the late Pleistocene using surface exposure dating with cosmogenic 10Be. A sequence of seven prominent moraines in northeastern Europe (the Leszno Moraine, the Pomeranian Moraine, the Middle Lithuanian Moraine, the North Lithuanian Moraine, the P andivere Moraine, the Palivere Moraine, and the Salpausselka I Moraine) indicates a potential millennialscale record of climate variability. However, there are no direct dating constraints on the timing of this ice sheet retreat. Surface exposure dating using cosmogenic nuclide elements produced by secondary high-energy particles in the upper part of the lithosphere allows for direct dating of moraines deposited by the SIS. Cosmogenic 10Be concentrations were measured in quartz sampled from erratic boulders deposited on top of the moraines. The SIS margin withdrew from its maximum extent at 17,9 ± 2,4 10Be ka, which is correlative to the end of the Last Glacial Maximum period (23,0 to 19,0 ka). Following a recessional period, the ice readvanced to the Pomeranian Moraine. Deglaciation from this moraine is dated at 14,1 ± 1,8 10Be ka, and subsequent deglaciation is marked by the Middle Lithuanian Moraine (13,1 ± 1,7 "Be ka), the North Lithuanian Moraine (13,1 ± 1,7 10Be ka), the Pandivere Moraine (13,0 ± 1,1 10Be ka), the Palivere Moraine (10.0 ± 1,3 10Be ka), and the Salpausselka I Moraine (12,5 ± 1,5 10Be ka). This new chronology is compared to abrupt climate variability recorded in the North Atlantic region during the late Pleistocene. Paleo air temperatures recorded from the GISP2 ice core and paleo sea surface temperatures recorded from the North Atlantic region display warmings at the end of the Last Glacial Maximum period, during the Balling-Allerod interstadial, and at the end of the Younger Dryas stadial. These records also display abrupt coolings during the Oldest Dryas and the Younger Dryas stadials. Based on the 10Be chronology, the margin of the SIS responded to climate changes that occurred in the North Atlantic region. This new chronology contributes the first direct evidence of climate forcing on the southern margin of the SIS. Close

• 24. [Article] Paleo-oceanography of the Gulf of California based on silicoflagellates from marine varved sediments

  Plankton and surface sediment samples from the Gulf of California were analyzed to determine the present geographic distribution of silicoflagellate species in this area. Variations in the composition ...

  Citation × Citation Citation Abstract Copy Title: Paleo-oceanography of the Gulf of California based on silicoflagellates from marine varved sediments Author: Murray, David W. Plankton and surface sediment samples from the Gulf of California were analyzed to determine the present geographic distribution of silicoflagellate species in this area. Variations in the composition of the silicoflagellate assemblage are related to water mass distributions. Seven species and three forms were identified in these samples. Octactis pulchra is associated with high levels of primary productivity in the surface waters and is found in greatest abundance in the central Gulf of California. Dictyocha messanensis dominates the silicoflagellate assemblage in stations outside the Gulf of California and increases in relative abundance with decreasing amounts of 0. pulchra. D. calida and D. spec. 1 forms are associated with equatorial waters and have the highest relative abundance near the mouth of the Gulf. D. epiodon and Distephanus speculum are associated with cold California Current Water and Dictyocha epiodon is present in minor abundance in Gulf samples. D. spec. 2 has a patchy distribution with low relative abundance in these samples. Downcore sediment samples were analyzed from six locations in the southern Gulf of California. The results suggest that major variations in the relative composition of the silicoflagellate assemblage have not occurred over the past 1000 years. Sediment material obtained from the basin slopes in the central Gulf of California exhibit alternating light and dark laminations. A laminae couplet equals one year of deposition. The composition of the silicoflagellate assemblage was determined in one hundred twenty individual laminae samples from the top section of a box core from the central Gulf. There is no indication of a characteristic assemblage composition associated with either light or dark laminations in these samples. A high relative abundance of 0. pulchra is present in the well laminated sections of the core. D. spec. 1, D. epiodon, D. calida, and D. spec. 2 are periodically in great abundance spanning more than one laminae sample. Variations in the relative abundance of silicoflagellate species in the central Gulf of California during the last 38,000 years were determined from DSDP Leg 64 Site 480 samples. The results indicate that 0. pulchra was in lower relative abundance and Distephanus speculum, Dictyocha epiodon, and D. spec. 1 forms were in greater abundance during the glacial period compared to the present. This suggests that there was a decrease in primary production, an increase in Pacific water influence, and a decrease in surface water temperatures in the central Gulf of California during the last major glacial interval compared to the present conditions. Title: Paleo-oceanography of the Gulf of California based on silicoflagellates from marine varved sediments Author: Murray, David W. Plankton and surface sediment samples from the Gulf of California were analyzed to determine the present geographic distribution of silicoflagellate species in this area. Variations in the composition of the silicoflagellate assemblage are related to water mass distributions. Seven species and three forms were identified in these samples. Octactis pulchra is associated with high levels of primary productivity in the surface waters and is found in greatest abundance in the central Gulf of California. Dictyocha messanensis dominates the silicoflagellate assemblage in stations outside the Gulf of California and increases in relative abundance with decreasing amounts of 0. pulchra. D. calida and D. spec. 1 forms are associated with equatorial waters and have the highest relative abundance near the mouth of the Gulf. D. epiodon and Distephanus speculum are associated with cold California Current Water and Dictyocha epiodon is present in minor abundance in Gulf samples. D. spec. 2 has a patchy distribution with low relative abundance in these samples. Downcore sediment samples were analyzed from six locations in the southern Gulf of California. The results suggest that major variations in the relative composition of the silicoflagellate assemblage have not occurred over the past 1000 years. Sediment material obtained from the basin slopes in the central Gulf of California exhibit alternating light and dark laminations. A laminae couplet equals one year of deposition. The composition of the silicoflagellate assemblage was determined in one hundred twenty individual laminae samples from the top section of a box core from the central Gulf. There is no indication of a characteristic assemblage composition associated with either light or dark laminations in these samples. A high relative abundance of 0. pulchra is present in the well laminated sections of the core. D. spec. 1, D. epiodon, D. calida, and D. spec. 2 are periodically in great abundance spanning more than one laminae sample. Variations in the relative abundance of silicoflagellate species in the central Gulf of California during the last 38,000 years were determined from DSDP Leg 64 Site 480 samples. The results indicate that 0. pulchra was in lower relative abundance and Distephanus speculum, Dictyocha epiodon, and D. spec. 1 forms were in greater abundance during the glacial period compared to the present. This suggests that there was a decrease in primary production, an increase in Pacific water influence, and a decrease in surface water temperatures in the central Gulf of California during the last major glacial interval compared to the present conditions. Close

• 25. [Article] Late Quaternary and Holocene Paleoecology of Interior Mesic Forests of Northern Idaho

  The mesic forests distributed within the Rocky Mountains of northern Idaho are unique because many species contained within the forest are separated from their main distribution along the Pacific Northwest ...

  Citation × Citation Citation Abstract Copy Title: Late Quaternary and Holocene Paleoecology of Interior Mesic Forests of Northern Idaho Author: Herring, Erin Year: 2014 The mesic forests distributed within the Rocky Mountains of northern Idaho are unique because many species contained within the forest are separated from their main distribution along the Pacific Northwest coast. It remains unclear whether most species within the inland disjunction survived the glacial periods of the Pleistocene, or whether they were more recently dispersed from coastal populations. To see if the dominant tree taxa of the mesic forests today could have persisted in a refugium south of the large ice sheets, four sediment cores were used to reconstruct the vegetation and climate history of the region. A nearly continuous record of pollen and sediment composition (biogenic silica and inorganic and organic matter) over the last ca. 120,000 years provides evidence of a dynamic ecosystem. Over a long timescale, the slow shifts in vegetation are attributed to the changes in climate. During the last interglacial period, the region was warmer and drier with a Pinus dominated mixed conifer forest. Approximately 71,000 years ago, a Pseudotsuga/Larix forest became established in the area as a response to the increased available moisture. As climate cooled and glaciers expanded the Pinus and Picea forest was the dominant vegetation type until ca. 40,000 years ago. The environment during the Last Glacial Maximum (LGM) was so harsh that no vegetation record was recorded. After the LGM, climate warmed, enabling a Pinus and Picea forest to establish and persist until the Holocene. The mesic taxa that dominate the modern forests did not arrive in northern Idaho until the mid- to late-Holocene. The recent arrival of the dominant tree species, Thuja plicata and Tsuga mertensiana, suggests that they likely did not persist in a refugium during the last glaciation. Instead, these species recently dispersed from coastal populations, but expansion into their interior distributions was likely limited by both climate and species competition in already established forests. During the late-Quaternary, the deposition of thick tephra layers (>20 cm) from the eruptions of Glacier Peak (ca. 13,400 years ago) and Mt. Mazama (ca. 7,600 years ago) also facilitated an abrupt and persistent change in vegetation in northern Idaho. Title: Late Quaternary and Holocene Paleoecology of Interior Mesic Forests of Northern Idaho Author: Herring, Erin Year: 2014 The mesic forests distributed within the Rocky Mountains of northern Idaho are unique because many species contained within the forest are separated from their main distribution along the Pacific Northwest coast. It remains unclear whether most species within the inland disjunction survived the glacial periods of the Pleistocene, or whether they were more recently dispersed from coastal populations. To see if the dominant tree taxa of the mesic forests today could have persisted in a refugium south of the large ice sheets, four sediment cores were used to reconstruct the vegetation and climate history of the region. A nearly continuous record of pollen and sediment composition (biogenic silica and inorganic and organic matter) over the last ca. 120,000 years provides evidence of a dynamic ecosystem. Over a long timescale, the slow shifts in vegetation are attributed to the changes in climate. During the last interglacial period, the region was warmer and drier with a Pinus dominated mixed conifer forest. Approximately 71,000 years ago, a Pseudotsuga/Larix forest became established in the area as a response to the increased available moisture. As climate cooled and glaciers expanded the Pinus and Picea forest was the dominant vegetation type until ca. 40,000 years ago. The environment during the Last Glacial Maximum (LGM) was so harsh that no vegetation record was recorded. After the LGM, climate warmed, enabling a Pinus and Picea forest to establish and persist until the Holocene. The mesic taxa that dominate the modern forests did not arrive in northern Idaho until the mid- to late-Holocene. The recent arrival of the dominant tree species, Thuja plicata and Tsuga mertensiana, suggests that they likely did not persist in a refugium during the last glaciation. Instead, these species recently dispersed from coastal populations, but expansion into their interior distributions was likely limited by both climate and species competition in already established forests. During the late-Quaternary, the deposition of thick tephra layers (>20 cm) from the eruptions of Glacier Peak (ca. 13,400 years ago) and Mt. Mazama (ca. 7,600 years ago) also facilitated an abrupt and persistent change in vegetation in northern Idaho. Close

• 26. [Article] Past climate variability in southwestern Oregon and relationships with regional and hemispheric climate

  This dissertation presents the results of three studies that assessed climate variability on short and long timescales in western United States. The growth of carbonate formations in caves (speleothems) ...

  Citation × Citation Citation Abstract Copy Title: Past climate variability in southwestern Oregon and relationships with regional and hemispheric climate Author: Ersek, Vasile This dissertation presents the results of three studies that assessed climate variability on short and long timescales in western United States. The growth of carbonate formations in caves (speleothems) is used to infer the timing and amplitude of past climate variability. We first assess the controls on speleothem growth for the past 380 000 years by combining high-density U-Th dating with a regional climate model and an energy balance model. The majority of speleothem growth occurred overwhelmingly during interglacial periods and glacial periods were characterized by little or no growth. We assess the mechanisms responsible for growth cessation during the peak of the last glaciation (LGM), 21 000 years ago, with a regional climate model and determine that a combination of drier LGM conditions with a change in the seasonal cycle of the surface water balance provides a feedback mechanism that limited recharge to the deeper soil and reduced or eliminated drip water in the cave. The energy balance model supports this mechanism by indicating that cave temperatures did not drop below the freezing point of water at any time during the last glaciation. We then evaluate the climatic significance of stable isotopes of oxygen in rainwater collected in southwestern Oregon in order to accurately interpret the isotopic record of speleothems. We establish that temperature plays an important role in controlling the distribution of oxygen isotopes in rainwater and therefore speleothems in southwestern Oregon can preserve a record of temperature changes through time. Finally, we present a high-resolution paleoclimate record using speleothems from a cave in Oregon that grew during the last 9000 years and during the middle of the last interglaciation. We find the winter temperatures were sensitive to winter solar insolation and varied in a quasi-cyclical pattern on millennial timescales. This pattern was characteristic of both regional and hemispheric variability as indicated by similarities of our record with other regional and hemispheric climate reconstructions. It appears that higher climate variability in the past was associated with warming trends, with the implication that global warming may make the climate more unstable in the future. Climate variability during the last interglacial period was characterized by different scales of millennial and centennial climate variability compared with the Holocene. Title: Past climate variability in southwestern Oregon and relationships with regional and hemispheric climate Author: Ersek, Vasile This dissertation presents the results of three studies that assessed climate variability on short and long timescales in western United States. The growth of carbonate formations in caves (speleothems) is used to infer the timing and amplitude of past climate variability. We first assess the controls on speleothem growth for the past 380 000 years by combining high-density U-Th dating with a regional climate model and an energy balance model. The majority of speleothem growth occurred overwhelmingly during interglacial periods and glacial periods were characterized by little or no growth. We assess the mechanisms responsible for growth cessation during the peak of the last glaciation (LGM), 21 000 years ago, with a regional climate model and determine that a combination of drier LGM conditions with a change in the seasonal cycle of the surface water balance provides a feedback mechanism that limited recharge to the deeper soil and reduced or eliminated drip water in the cave. The energy balance model supports this mechanism by indicating that cave temperatures did not drop below the freezing point of water at any time during the last glaciation. We then evaluate the climatic significance of stable isotopes of oxygen in rainwater collected in southwestern Oregon in order to accurately interpret the isotopic record of speleothems. We establish that temperature plays an important role in controlling the distribution of oxygen isotopes in rainwater and therefore speleothems in southwestern Oregon can preserve a record of temperature changes through time. Finally, we present a high-resolution paleoclimate record using speleothems from a cave in Oregon that grew during the last 9000 years and during the middle of the last interglaciation. We find the winter temperatures were sensitive to winter solar insolation and varied in a quasi-cyclical pattern on millennial timescales. This pattern was characteristic of both regional and hemispheric variability as indicated by similarities of our record with other regional and hemispheric climate reconstructions. It appears that higher climate variability in the past was associated with warming trends, with the implication that global warming may make the climate more unstable in the future. Climate variability during the last interglacial period was characterized by different scales of millennial and centennial climate variability compared with the Holocene. Close

• 27. [Article] Holocene vegetation and fire history of the floristically diverse Klamath Mountains, northern California, USA

  xiv, 227 p. : ill. (some col.) A print copy of this title is available through the UO Libraries under the call numbers: KNIGHT QE720.2.K53 B75 2008

  Citation × Citation Citation Abstract Copy Title: Holocene vegetation and fire history of the floristically diverse Klamath Mountains, northern California, USA Author: Briles, Christy Elaine, 1976- Year: 2008 xiv, 227 p. : ill. (some col.) A print copy of this title is available through the UO Libraries under the call numbers: KNIGHT QE720.2.K53 B75 2008 Title: Holocene vegetation and fire history of the floristically diverse Klamath Mountains, northern California, USA Author: Briles, Christy Elaine, 1976- Year: 2008 xiv, 227 p. : ill. (some col.) A print copy of this title is available through the UO Libraries under the call numbers: KNIGHT QE720.2.K53 B75 2008 Close

• 28. [Article] Onset of deglacial warming in West Antarctica driven by local orbital forcing

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Macmillan ...

  Citation × Citation Citation Abstract Copy Title: Onset of deglacial warming in West Antarctica driven by local orbital forcing Author: Mortensen, Nicolai, Edwards, R. Lawrence, Popp, Trevor J., Brook, Edward J., Neff, Peter, Edwards, Ross, Sowers, Todd, Cole-Dai, Jihong, Markle, Bradley R., Johnson, Jay, Hargreaves, Geoffrey, Schauer, Andrew J., Cuffey, Kurt M., Fegyveresi, John M., White, James W. C., Alley, Richard B., Clow, Gary D., McGwire, Kenneth C., Ding, Qinghua, Mitchell, Logan E., Fitzpatrick, Joan J., Schoenemann, Spruce W., Steig, Eric J., Fudge, T. J., Maselli, Olivia J., Mason, William, Ferris, David, Orsi, Anais J., Edwards, Jon S., Taylor, Kendrick C., McConnell, Joseph R., Conway, Howard, Lee, James E., Cheng, Hai To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Macmillan Publishers Limited and can be found at: http://www.macmillan.com/. Title: Onset of deglacial warming in West Antarctica driven by local orbital forcing Author: Mortensen, Nicolai, Edwards, R. Lawrence, Popp, Trevor J., Brook, Edward J., Neff, Peter, Edwards, Ross, Sowers, Todd, Cole-Dai, Jihong, Markle, Bradley R., Johnson, Jay, Hargreaves, Geoffrey, Schauer, Andrew J., Cuffey, Kurt M., Fegyveresi, John M., White, James W. C., Alley, Richard B., Clow, Gary D., McGwire, Kenneth C., Ding, Qinghua, Mitchell, Logan E., Fitzpatrick, Joan J., Schoenemann, Spruce W., Steig, Eric J., Fudge, T. J., Maselli, Olivia J., Mason, William, Ferris, David, Orsi, Anais J., Edwards, Jon S., Taylor, Kendrick C., McConnell, Joseph R., Conway, Howard, Lee, James E., Cheng, Hai To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Macmillan Publishers Limited and can be found at: http://www.macmillan.com/. Close

• 29. [Article] Relative timing and variability of atmospheric methane and GISP2 oxygen isotopes between 68 and 86 ka

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/gb/index.shtml.

  Citation × Citation Citation Abstract Copy Title: Relative timing and variability of atmospheric methane and GISP2 oxygen isotopes between 68 and 86 ka Author: Brook, Edward J., Severinghaus, Jeffrey P., Grachev, Alexi M., Pisias, Nicklas G. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/gb/index.shtml. Title: Relative timing and variability of atmospheric methane and GISP2 oxygen isotopes between 68 and 86 ka Author: Brook, Edward J., Severinghaus, Jeffrey P., Grachev, Alexi M., Pisias, Nicklas G. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/gb/index.shtml. Close

• 30. [Article] Precise interpolar phasing of abrupt climate change during the last ice age

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Nature ...

  Citation × Citation Citation Abstract Copy Title: Precise interpolar phasing of abrupt climate change during the last ice age Author: Rhodes, Rachael H., Rosen, Julia L., Kalk, Michael L., Buizert, Christo, Edwards, Jon S., Adrian, Betty, Bauska, Thomas K., Marcott, Shaun A., et al., Mitchell, Logan E., Lee, James E., Brook, Edward J., Ahn, Jinho To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Nature Publishing Group and can be found at: http://www.nature.com/nature/index.html. Supporting Information can be found at: http://www.nature.com/nature/journal/v520/n7549/full/nature14401.html#/supplementary-information Title: Precise interpolar phasing of abrupt climate change during the last ice age Author: Rhodes, Rachael H., Rosen, Julia L., Kalk, Michael L., Buizert, Christo, Edwards, Jon S., Adrian, Betty, Bauska, Thomas K., Marcott, Shaun A., et al., Mitchell, Logan E., Lee, James E., Brook, Edward J., Ahn, Jinho To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Nature Publishing Group and can be found at: http://www.nature.com/nature/index.html. Supporting Information can be found at: http://www.nature.com/nature/journal/v520/n7549/full/nature14401.html#/supplementary-information Close