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• 481. [Article] Comparison between Observed and Model-Simulated Atmospheric CirculationPatterns Associated with Extreme Temperature Days over North AmericaUsing CMIP5 Historical Simulations

  Circulation patterns associated with extreme temperature days over North America, as simulated by a suite of climate models, are compared with those obtained from observations. The authors analyze 17 coupled ...

  Citation × Citation Citation Abstract Copy Title: Comparison between Observed and Model-Simulated Atmospheric CirculationPatterns Associated with Extreme Temperature Days over North AmericaUsing CMIP5 Historical Simulations Author: Loikith, Paul C., Broccoli, Anthony J. Year: 2015 Circulation patterns associated with extreme temperature days over North America, as simulated by a suite of climate models, are compared with those obtained from observations. The authors analyze 17 coupled atmosphere–ocean general circulation models contributing to the fifth phase of the Coupled Model Intercomparison Project. Circulation patterns are defined as composites of anomalies in sea level pressure and 500-hPa geopotential height concurrent with days in the tails of temperature distribution. Several metrics used to systematically describe circulation patterns associated with extreme temperature days are applied to both the observed and model-simulated data. Additionally, self-organizing maps are employed as a means of comparing observed and model-simulated circulation patterns across the North American domain. In general, the multimodel ensemble resembles the observed patterns well, especially in areas removed from complex geographic features (e.g., mountains and coastlines). Individual model results vary; however, the majority of models capture the major features observed. The multimodel ensemble captures several key features, including regional variations in the strength and orientation of atmospheric circulation patterns associated with extreme temperatures, both near the surface and aloft, as well as variations with latitude and season. The results from this work suggest that these models can be used to comprehensively examine the role that changes in atmospheric circulation will play in projected changes in temperature extremes because of future anthropogenic climate warming. Title: Comparison between Observed and Model-Simulated Atmospheric CirculationPatterns Associated with Extreme Temperature Days over North AmericaUsing CMIP5 Historical Simulations Author: Loikith, Paul C., Broccoli, Anthony J. Year: 2015 Circulation patterns associated with extreme temperature days over North America, as simulated by a suite of climate models, are compared with those obtained from observations. The authors analyze 17 coupled atmosphere–ocean general circulation models contributing to the fifth phase of the Coupled Model Intercomparison Project. Circulation patterns are defined as composites of anomalies in sea level pressure and 500-hPa geopotential height concurrent with days in the tails of temperature distribution. Several metrics used to systematically describe circulation patterns associated with extreme temperature days are applied to both the observed and model-simulated data. Additionally, self-organizing maps are employed as a means of comparing observed and model-simulated circulation patterns across the North American domain. In general, the multimodel ensemble resembles the observed patterns well, especially in areas removed from complex geographic features (e.g., mountains and coastlines). Individual model results vary; however, the majority of models capture the major features observed. The multimodel ensemble captures several key features, including regional variations in the strength and orientation of atmospheric circulation patterns associated with extreme temperatures, both near the surface and aloft, as well as variations with latitude and season. The results from this work suggest that these models can be used to comprehensively examine the role that changes in atmospheric circulation will play in projected changes in temperature extremes because of future anthropogenic climate warming. Close

• 482. [Article] Reverse Gyrase is Not Necessary for Survival of Hyperthermophilic Archaeon Pyrococcus Furiosus

  Reverse gyrase is the only known topoisomerase enzyme with positive supercoiling activity on covalently-closed DNA. This positive supercoiling is required to prevent DNA from denaturation at high temperatures. ...

  Citation × Citation Citation Abstract Copy Title: Reverse Gyrase is Not Necessary for Survival of Hyperthermophilic Archaeon Pyrococcus Furiosus Author: Taghizadeh, Farshid, Bartlett, Michael S. Year: 2015 Reverse gyrase is the only known topoisomerase enzyme with positive supercoiling activity on covalently-closed DNA. This positive supercoiling is required to prevent DNA from denaturation at high temperatures. The gene that codes for this protein is present in all hyperthermophiles and absent from all mesophilic and thermophilic genomes, suggesting that this enzyme is the only hyperthermophile-specific protein. To investigate if this protein is vital for the cells, we knocked out its gene from the genome of living organism Pyrococcus furiosus. Pyrococcus furiosus is a hyperthermophilic archaeon that grows between 70°C to 103°C with an optimum growth temperature of 100°C. The knocking out process was done as follows. Recombinant DNA was made using Gibson Assembly technique. This DNA, which included a selection marker for ability to synthesize uracil, was used to transform Pyrococcus furiosus strain ‘COM1’. Uracil prototrophs were selected on growth medium lacking uracil, and the deletion of the target gene was confirmed using PCR. Mutants then were grown at different temperatures ranging from 75°C to 105°C and growth curves were compared to that of COM1. Although mutants do not survive at temperatures over 93°C, no significant difference was observed between the growth rate and density of COM1 and mutants in temperatures below that. We demonstrated that although reverse gyrase is not essential for cell survival, it shifts the maximum living temperature from 103°C to 93°C. Title: Reverse Gyrase is Not Necessary for Survival of Hyperthermophilic Archaeon Pyrococcus Furiosus Author: Taghizadeh, Farshid, Bartlett, Michael S. Year: 2015 Reverse gyrase is the only known topoisomerase enzyme with positive supercoiling activity on covalently-closed DNA. This positive supercoiling is required to prevent DNA from denaturation at high temperatures. The gene that codes for this protein is present in all hyperthermophiles and absent from all mesophilic and thermophilic genomes, suggesting that this enzyme is the only hyperthermophile-specific protein. To investigate if this protein is vital for the cells, we knocked out its gene from the genome of living organism Pyrococcus furiosus. Pyrococcus furiosus is a hyperthermophilic archaeon that grows between 70°C to 103°C with an optimum growth temperature of 100°C. The knocking out process was done as follows. Recombinant DNA was made using Gibson Assembly technique. This DNA, which included a selection marker for ability to synthesize uracil, was used to transform Pyrococcus furiosus strain ‘COM1’. Uracil prototrophs were selected on growth medium lacking uracil, and the deletion of the target gene was confirmed using PCR. Mutants then were grown at different temperatures ranging from 75°C to 105°C and growth curves were compared to that of COM1. Although mutants do not survive at temperatures over 93°C, no significant difference was observed between the growth rate and density of COM1 and mutants in temperatures below that. We demonstrated that although reverse gyrase is not essential for cell survival, it shifts the maximum living temperature from 103°C to 93°C. Close

• 483. [Article] Effect of temperature and tissue type on fatty acid signatures of two species of North Pacific juvenile gadids: A laboratory feeding study

  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 Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Effect of temperature and tissue type on fatty acid signatures of two species of North Pacific juvenile gadids: A laboratory feeding study Author: Parrish, Christopher C., Laurel, Benjamin J., Copeman, Louise A. 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 Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-experimental-marine-biology-and-ecology/. Title: Effect of temperature and tissue type on fatty acid signatures of two species of North Pacific juvenile gadids: A laboratory feeding study Author: Parrish, Christopher C., Laurel, Benjamin J., Copeman, Louise A. 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 Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-experimental-marine-biology-and-ecology/. Close

• 484. [Article] Individual condition, standard metabolic rate, and rearing temperature influence steelhead and rainbow trout (Oncorhynchus mykiss) life histories

  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 NRC Research ...

  Citation × Citation Citation Abstract Copy Title: Individual condition, standard metabolic rate, and rearing temperature influence steelhead and rainbow trout (Oncorhynchus mykiss) life histories Author: Reeves, Gordon H., Sloat, Matthew R. 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 NRC Research Press and can be found at: http://www.nrcresearchpress.com/journal/cjfas. Title: Individual condition, standard metabolic rate, and rearing temperature influence steelhead and rainbow trout (Oncorhynchus mykiss) life histories Author: Reeves, Gordon H., Sloat, Matthew R. 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 NRC Research Press and can be found at: http://www.nrcresearchpress.com/journal/cjfas. Close

• 485. [Article] Temperature-dependent growth and behavior of juvenile Arctic cod (Boreogadus saida) and co-occurring North Pacific gadids

  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 article is copyrighted by the US Government ...

  Citation × Citation Citation Abstract Copy Title: Temperature-dependent growth and behavior of juvenile Arctic cod (Boreogadus saida) and co-occurring North Pacific gadids Author: Iseri, Paul, Spencer, Mara, Laurel, Benjamin J., Copeman, Louise A. 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 article is copyrighted by the US Government and published by Springer. It can be found at: http://link.springer.com/journal/300 Title: Temperature-dependent growth and behavior of juvenile Arctic cod (Boreogadus saida) and co-occurring North Pacific gadids Author: Iseri, Paul, Spencer, Mara, Laurel, Benjamin J., Copeman, Louise A. 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 article is copyrighted by the US Government and published by Springer. It can be found at: http://link.springer.com/journal/300 Close

• 486. [Article] Local atmospheric decoupling in complex topography alters climate change impacts

  Supplementary material included in separate file. This article was originally published in International Journal of Climatology and is copyrighted by the Royal Meteorological Society

  Citation × Citation Citation Abstract Copy Title: Local atmospheric decoupling in complex topography alters climate change impacts Author: Unsworth, Michael H., Daly, Christopher, Conklin, David R. Supplementary material included in separate file. This article was originally published in International Journal of Climatology and is copyrighted by the Royal Meteorological Society Title: Local atmospheric decoupling in complex topography alters climate change impacts Author: Unsworth, Michael H., Daly, Christopher, Conklin, David R. Supplementary material included in separate file. This article was originally published in International Journal of Climatology and is copyrighted by the Royal Meteorological Society Close

• 487. [Article] Climate change impacts on maritime mountain snowpack in the Oregon Cascades

  This is the publisher’s final pdf. The published article is copyrighted by Copernicus Publications and can be found at: http://publications.copernicus.org/.

  Citation × Citation Citation Abstract Copy Title: Climate change impacts on maritime mountain snowpack in the Oregon Cascades Author: Sproles, E. A., Nolin, A.W., Rittger, K., Painter, T. H. This is the publisher’s final pdf. The published article is copyrighted by Copernicus Publications and can be found at: http://publications.copernicus.org/. Title: Climate change impacts on maritime mountain snowpack in the Oregon Cascades Author: Sproles, E. A., Nolin, A.W., Rittger, K., Painter, T. H. This is the publisher’s final pdf. The published article is copyrighted by Copernicus Publications and can be found at: http://publications.copernicus.org/. Close

• 488. [Article] Mixing Measurements on an Equatorial Ocean Mooring

  Vaned, internally recording instruments that measure temperature fluctuations using FP07 thermistors, including fluctuations in the turbulence wavenumber band, have been built, tested, and deployed on ...

  Citation × Citation Citation Abstract Copy Title: Mixing Measurements on an Equatorial Ocean Mooring Author: Moum, J. N., Nash, J. D. Vaned, internally recording instruments that measure temperature fluctuations using FP07 thermistors, including fluctuations in the turbulence wavenumber band, have been built, tested, and deployed on a Tropical Atmosphere Ocean (TAO) mooring at 0°, 140°W. These were supplemented with motion packages that measure linear accelerations, from which an assessment of cable displacement and speed was made. Motions due to vortex-induced vibrations caused by interaction of the mean flow with the cable are small (rms < 0.15 cable diameters) and unlikely to affect estimates of the temperature variance dissipation rate χ[subscript]T. Surface wave–induced cable motions are significant, commonly resulting in vertical displacements of ±1 m and vertical speeds of ±0.5 m s⁻¹ on 2–10-s periods. These motions produce an enhancement to the measurement of temperature gradient in the surface wave band herein that is equal to the product of the vertical cable speed and the vertical temperature gradient (i.e., dT/dt ~w[subscript]cdT/dz). However, the temperature gradient spectrum is largely unaltered at higher and lower frequencies; in particular, there exists a clear scale separation between frequencies contaminated by surface waves and the turbulence subrange. The effect of cable motions on spectral estimates of χ[subscript]T is evaluated and determined to result in acceptably small uncertainties (< a factor of two 95% of the time, based on 60-s averages). Time series of χT and the inferred turbulent kinetic energy dissipation rate ϵ are consistent with historical data from the same equatorial location. Title: Mixing Measurements on an Equatorial Ocean Mooring Author: Moum, J. N., Nash, J. D. Vaned, internally recording instruments that measure temperature fluctuations using FP07 thermistors, including fluctuations in the turbulence wavenumber band, have been built, tested, and deployed on a Tropical Atmosphere Ocean (TAO) mooring at 0°, 140°W. These were supplemented with motion packages that measure linear accelerations, from which an assessment of cable displacement and speed was made. Motions due to vortex-induced vibrations caused by interaction of the mean flow with the cable are small (rms < 0.15 cable diameters) and unlikely to affect estimates of the temperature variance dissipation rate χ[subscript]T. Surface wave–induced cable motions are significant, commonly resulting in vertical displacements of ±1 m and vertical speeds of ±0.5 m s⁻¹ on 2–10-s periods. These motions produce an enhancement to the measurement of temperature gradient in the surface wave band herein that is equal to the product of the vertical cable speed and the vertical temperature gradient (i.e., dT/dt ~w[subscript]cdT/dz). However, the temperature gradient spectrum is largely unaltered at higher and lower frequencies; in particular, there exists a clear scale separation between frequencies contaminated by surface waves and the turbulence subrange. The effect of cable motions on spectral estimates of χ[subscript]T is evaluated and determined to result in acceptably small uncertainties (< a factor of two 95% of the time, based on 60-s averages). Time series of χT and the inferred turbulent kinetic energy dissipation rate ϵ are consistent with historical data from the same equatorial location. Close

• 489. [Article] Evolution of the northeast Labrador Sea during the last interglaciation

  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/gc/.

  Citation × Citation Citation Abstract Copy Title: Evolution of the northeast Labrador Sea during the last interglaciation Author: Stoner, Joseph S., Carlson, Anders E., Hatfield, Robert G., Winsor, Kelsey, Klinkhammer, Gary P. 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/gc/. Title: Evolution of the northeast Labrador Sea during the last interglaciation Author: Stoner, Joseph S., Carlson, Anders E., Hatfield, Robert G., Winsor, Kelsey, Klinkhammer, Gary P. 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/gc/. Close

• 490. [Article] Towed thermister chain observations of fronts in the subtropical North Pacific

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Towed thermister chain observations of fronts in the subtropical North Pacific Author: Paulson, Clayton A., Samelson, Roger M. Copyrighted by American Geophysical Union. Title: Towed thermister chain observations of fronts in the subtropical North Pacific Author: Paulson, Clayton A., Samelson, Roger M. Copyrighted by American Geophysical Union. Close