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• 1011. [Article] Glacial greenhouse-gas fluctuations controlled by ocean circulation changes

  Earth's climate and the concentrations of the atmospheric greenhouse gases carbon dioxide (CO2) and nitrous oxide (N2O) varied strongly on millennial timescales during past glacial periods. Large and rapid ...

  Citation × Citation Citation Abstract Copy Title: Glacial greenhouse-gas fluctuations controlled by ocean circulation changes Author: Schmittner, Andreas, Galbraith, Eric D. Earth's climate and the concentrations of the atmospheric greenhouse gases carbon dioxide (CO2) and nitrous oxide (N2O) varied strongly on millennial timescales during past glacial periods. Large and rapid warming events in Greenland and the North Atlantic were followed by more gradual cooling, and are highly correlated with fluctuations of N2O as recorded in ice cores. Antarctic temperature variations, on the other hand, were smaller and more gradual, showed warming during the Greenland cold phase and cooling while the North Atlantic was warm, and were highly correlated with fluctuations in CO2. Abrupt changes in the Atlantic meridional overturning circulation (AMOC) have often been invoked to explain the physical characteristics of these Dansgaard–Oeschger climate oscillations, but the mechanisms for the greenhouse-gas variations and their linkage to the AMOC have remained unclear. Here we present simulations with a coupled model of glacial climate and biogeochemical cycles, forced only with changes in the AMOC. The model simultaneously reproduces characteristic features of the Dansgaard–Oeschger temperature, as well as CO2 and N2O fluctuations. Despite significant changes in the land carbon inventory, CO2 variations on millennial timescales are dominated by slow changes in the deep ocean inventory of biologically sequestered carbon and are correlated with Antarctic temperature and Southern Ocean stratification. In contrast, N2O co-varies more rapidly with Greenland temperatures owing to fast adjustments of the thermocline oxygen budget. These results suggest that ocean circulation changes were the primary mechanism that drove glacial CO2 and N2O fluctuations on millennial timescales. Title: Glacial greenhouse-gas fluctuations controlled by ocean circulation changes Author: Schmittner, Andreas, Galbraith, Eric D. Earth's climate and the concentrations of the atmospheric greenhouse gases carbon dioxide (CO2) and nitrous oxide (N2O) varied strongly on millennial timescales during past glacial periods. Large and rapid warming events in Greenland and the North Atlantic were followed by more gradual cooling, and are highly correlated with fluctuations of N2O as recorded in ice cores. Antarctic temperature variations, on the other hand, were smaller and more gradual, showed warming during the Greenland cold phase and cooling while the North Atlantic was warm, and were highly correlated with fluctuations in CO2. Abrupt changes in the Atlantic meridional overturning circulation (AMOC) have often been invoked to explain the physical characteristics of these Dansgaard–Oeschger climate oscillations, but the mechanisms for the greenhouse-gas variations and their linkage to the AMOC have remained unclear. Here we present simulations with a coupled model of glacial climate and biogeochemical cycles, forced only with changes in the AMOC. The model simultaneously reproduces characteristic features of the Dansgaard–Oeschger temperature, as well as CO2 and N2O fluctuations. Despite significant changes in the land carbon inventory, CO2 variations on millennial timescales are dominated by slow changes in the deep ocean inventory of biologically sequestered carbon and are correlated with Antarctic temperature and Southern Ocean stratification. In contrast, N2O co-varies more rapidly with Greenland temperatures owing to fast adjustments of the thermocline oxygen budget. These results suggest that ocean circulation changes were the primary mechanism that drove glacial CO2 and N2O fluctuations on millennial timescales. Close

• 1012. [Article] Oceanic germanium/silicon ratios: Evaluation of the potential overprint of temperature on weathering signals

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Oceanic germanium/silicon ratios: Evaluation of the potential overprint of temperature on weathering signals Author: McManus, James, Berelson, William M., Hammond, Douglas E. Copyrighted by American Geophysical Union. Title: Oceanic germanium/silicon ratios: Evaluation of the potential overprint of temperature on weathering signals Author: McManus, James, Berelson, William M., Hammond, Douglas E. Copyrighted by American Geophysical Union. Close

• 1013. [Article] A Semi-Empirical Inversion Model for Assessing Surface Soil Moisture using AMSR-E Brightness Temperatures

  This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-hydr...

  Citation × Citation Citation Abstract Copy Title: A Semi-Empirical Inversion Model for Assessing Surface Soil Moisture using AMSR-E Brightness Temperatures Author: Han, Liusheng, Liao, Jishan, Li, Dan, Li, Xia, Chen, Shuisen, Su, Yongxian, Chen, Xiuzhi, Li, Yong, Zhong, Ruofei This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-hydrology/. Title: A Semi-Empirical Inversion Model for Assessing Surface Soil Moisture using AMSR-E Brightness Temperatures Author: Han, Liusheng, Liao, Jishan, Li, Dan, Li, Xia, Chen, Shuisen, Su, Yongxian, Chen, Xiuzhi, Li, Yong, Zhong, Ruofei This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-hydrology/. Close

• 1014. [Article] Diurnal heat balance for the northern Monterey Bay inner shelf

  This is the publisher's version of record. The original submission is copyrighted by American Geophysical Union and can be found here: http://www.agu.org/

  Citation × Citation Citation Abstract Copy Title: Diurnal heat balance for the northern Monterey Bay inner shelf Author: S. H. Suanda, S. H., Barth, J. A., Woodson, C. B. This is the publisher's version of record. The original submission is copyrighted by American Geophysical Union and can be found here: http://www.agu.org/ Title: Diurnal heat balance for the northern Monterey Bay inner shelf Author: S. H. Suanda, S. H., Barth, J. A., Woodson, C. B. This is the publisher's version of record. The original submission is copyrighted by American Geophysical Union and can be found here: http://www.agu.org/ Close

• 1015. [Article] The signature of El Nino off Oregon, 1982-1983

  National Science Foundation through grants OCE-8026131, OCE-8405232, OCE-8014943 and OCE-8315014.

  Citation × Citation Citation Abstract Copy Title: The signature of El Nino off Oregon, 1982-1983 Author: Smith, Robert L. (Robert Lloyd), 1935-, Huyer, Adriana, 1945- National Science Foundation through grants OCE-8026131, OCE-8405232, OCE-8014943 and OCE-8315014. Title: The signature of El Nino off Oregon, 1982-1983 Author: Smith, Robert L. (Robert Lloyd), 1935-, Huyer, Adriana, 1945- National Science Foundation through grants OCE-8026131, OCE-8405232, OCE-8014943 and OCE-8315014. Close

• 1016. [Article] Evaluation of the air-sea bulk formula and sea-surface temperature variability from observations

  Citation × Citation Citation Abstract Copy Title: Evaluation of the air-sea bulk formula and sea-surface temperature variability from observations Author: Vickers, Dean, Mahrt, Larry Title: Evaluation of the air-sea bulk formula and sea-surface temperature variability from observations Author: Vickers, Dean, Mahrt, Larry Close

• 1017. [Article] Comment on "Ground vs. surface air temperature trends: implications for borehole surface reconstructions" by M.E. Mann and G. Schmidt

  Citation × Citation Citation Abstract Copy Title: Comment on "Ground vs. surface air temperature trends: implications for borehole surface reconstructions" by M.E. Mann and G. Schmidt Author: Harriss, Robert N., Bartlett, Marshall G., Chapman, David S. Title: Comment on "Ground vs. surface air temperature trends: implications for borehole surface reconstructions" by M.E. Mann and G. Schmidt Author: Harriss, Robert N., Bartlett, Marshall G., Chapman, David S. Close

• 1018. [Article] Ontogenetic patterns and temperature-dependent growth rates in early life stages of Pacific cod (Gadus macrocephalus)

  Pacific cod (Gadus macrocephalus) is an important component of fisheries and food webs in the North Pacific Ocean and Bering Sea. However, vital rates of early life stages of this species have yet to be ...

  Citation × Citation Citation Abstract Copy Title: Ontogenetic patterns and temperature-dependent growth rates in early life stages of Pacific cod (Gadus macrocephalus) Author: Ciannelli, Lorenzo, Hurst, Thomas P., Laurel, Benjamin J. Pacific cod (Gadus macrocephalus) is an important component of fisheries and food webs in the North Pacific Ocean and Bering Sea. However, vital rates of early life stages of this species have yet to be described in detail. We determined the thermal sensitivity of growth rates of embryos, pref lexion and postf lexion larvae, and postsettlement juveniles. Growth rates (length and mass) at each ontogenetic stage were measured in three replicate tanks at four to five temperatures. Nonlinear regression was used to obtain parameters for independent stage-specific growth functions and a unified size- and temperature- dependent growth function. Specific growth rates increased with temperature at all stages and generally decreased with increases in body size. However, these analyses revealed a departure from a strict size-based allometry in growth patterns, as reduced growth rates were observed among pref lexion larvae: the reduction in specific growth rate between embryos and free-swimming larvae was greater than expected based on body size differences. Growth reductions in the preflexion larvae appear to be associated with increased metabolic rates and the transition from endogenous to exogenous feeding. In future studies, experiments should be integrated across life transitions to more clearly define intrinsic ontogenetic and size-dependent growth patterns because these are critical for evaluations of spatial and temporal variation in habitat quality. Title: Ontogenetic patterns and temperature-dependent growth rates in early life stages of Pacific cod (Gadus macrocephalus) Author: Ciannelli, Lorenzo, Hurst, Thomas P., Laurel, Benjamin J. Pacific cod (Gadus macrocephalus) is an important component of fisheries and food webs in the North Pacific Ocean and Bering Sea. However, vital rates of early life stages of this species have yet to be described in detail. We determined the thermal sensitivity of growth rates of embryos, pref lexion and postf lexion larvae, and postsettlement juveniles. Growth rates (length and mass) at each ontogenetic stage were measured in three replicate tanks at four to five temperatures. Nonlinear regression was used to obtain parameters for independent stage-specific growth functions and a unified size- and temperature- dependent growth function. Specific growth rates increased with temperature at all stages and generally decreased with increases in body size. However, these analyses revealed a departure from a strict size-based allometry in growth patterns, as reduced growth rates were observed among pref lexion larvae: the reduction in specific growth rate between embryos and free-swimming larvae was greater than expected based on body size differences. Growth reductions in the preflexion larvae appear to be associated with increased metabolic rates and the transition from endogenous to exogenous feeding. In future studies, experiments should be integrated across life transitions to more clearly define intrinsic ontogenetic and size-dependent growth patterns because these are critical for evaluations of spatial and temporal variation in habitat quality. Close

• 1019. [Article] Drying Oregon white oak lumber

  Oregon white oak, Quercus garryana Dougl., could have greater commercial use, but information on its drying properties is lacking. All oaks are difficult to dry, and the initial kiln conditions are important ...

  Citation × Citation Citation Abstract Copy Title: Drying Oregon white oak lumber Author: Kozlik, Charles J., Oregon State University. Forest Research Laboratory, Espenas, Leif D. Oregon white oak, Quercus garryana Dougl., could have greater commercial use, but information on its drying properties is lacking. All oaks are difficult to dry, and the initial kiln conditions are important to prevent excessive surface checking and honeycombing. This study illustrated that a maximum dry-bulb temperature of 110 F with a wet-bulb depression of 4 F is required to reduce checking and must be maintained until the average moisture content is 40 percent or lower. The second stage of drying required a dry-bulb temperature of 110 F with a depression of 6 F and is held until the average moisture content is 30 percent. The drying conditions are set to promote drying until the equalization period, which is a dry-bulb temperature of 180 F and a wet-bulb depression of 35 F. This is followed by a conditioning period, which is a dry-bulb temperature of 180 F with a wet-bulb depression of 10 F. Drying times ranged from 21 days for 4/4 (1-inch thick) lumber, to 32 days for 5/4 (1'44-inch thick) lumber, and 43 days for 6/4 (1 V2-inch thick) lumber. Air drying to an average moisture content of 15-20 percent will reduce kiln-drying time for 4/4 lumber from 4 to 5 days. Title: Drying Oregon white oak lumber Author: Kozlik, Charles J., Oregon State University. Forest Research Laboratory, Espenas, Leif D. Oregon white oak, Quercus garryana Dougl., could have greater commercial use, but information on its drying properties is lacking. All oaks are difficult to dry, and the initial kiln conditions are important to prevent excessive surface checking and honeycombing. This study illustrated that a maximum dry-bulb temperature of 110 F with a wet-bulb depression of 4 F is required to reduce checking and must be maintained until the average moisture content is 40 percent or lower. The second stage of drying required a dry-bulb temperature of 110 F with a depression of 6 F and is held until the average moisture content is 30 percent. The drying conditions are set to promote drying until the equalization period, which is a dry-bulb temperature of 180 F and a wet-bulb depression of 35 F. This is followed by a conditioning period, which is a dry-bulb temperature of 180 F with a wet-bulb depression of 10 F. Drying times ranged from 21 days for 4/4 (1-inch thick) lumber, to 32 days for 5/4 (1'44-inch thick) lumber, and 43 days for 6/4 (1 V2-inch thick) lumber. Air drying to an average moisture content of 15-20 percent will reduce kiln-drying time for 4/4 lumber from 4 to 5 days. Close

• 1020. [Article] An oceanic microstructure measuring system

  Citation × Citation Citation Abstract Copy Title: An oceanic microstructure measuring system Author: Caldwell, D. R. (Douglas R.), Dillon, T. M. (Thomas M.), Oregon State University. School of Oceanography Title: An oceanic microstructure measuring system Author: Caldwell, D. R. (Douglas R.), Dillon, T. M. (Thomas M.), Oregon State University. School of Oceanography Close