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Distributed modeling of ablation (1996–2011) and climate sensitivity on the glaciers of Taylor Valley, Antarctica
Here, the McMurdo Dry Valleys of Antarctica host the coldest and driest ecosystem on Earth, which is acutely sensitive to the availability of water coming from glacial runoff. We modeled the spatial variability in ablation and assessed climate sensitivity of the glacier ablation zones using 16 years of meteorological and surface mass-balance observations collected in Taylor Valley. Sublimation was the primary form of mass loss over much of the ablation zones, except for near the termini where melt, primarily below the surface, dominated. Microclimates in ~10 m scale topographic basins generated melt rates up to ten times higher than over smooth glacier surfaces. In contrast, the vertical terminal cliffs on the glaciers can have higher or lower melt rates than the horizontal surfaces due to differences in incoming solar radiation. The model systematically underpredicted ablation for the final 5 years studied, possibly due to an increase of windblown sediment. Surface mass-balance sensitivity to temperature was ~–0.02 m w.e. K –1 , which is among the smallest magnitudes observed globally. We also identified a high sensitivity to ice albedo, with a decrease of 0.02 having similar effects as a 1 K increase in temperature, and a complex sensitivity to wind speed.
Simulation of Coal Ash Particle Deposition Experiments
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Organometallics Roundtable 2011
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Castagna, M., M. W. Becker, and A. Bellin (2011), Joint estimation of transmissivity and storativity in a bedrock fracture, Water Resour. Res., 47, W09504, doi:10.1029/2010WR009262.
The spatial variability of transmissivity (T) and storativity (S) in a sandstone bedding plane fracture was investigated through field and numerical hydraulic tomography experiments. Cross-hole pumping tests were conducted in a single subhorizontal bedrock fracture, thereby constraining the problem to two dimensions. A Bayesian method implementing pilot points was used to invert the drawdown, under the hypothesis that T and S are independent random space functions, where integral scale, mean, and variance of the random fields were parameters of inversion in addition to pilot point values. An ensemble of 20 Monte Carlo realizations was created for each model scenario. Inversion of the measured cross-hole drawdown resulted in spatially variable T and S fields. To determine the accuracy of the method, a suite of synthetic inversions modeled after the field site were also conducted. The synthetic experiments demonstrate that the assumed spatial structure of S influences the accuracy of both the T and S inversions. When the S field is spatially heterogeneous and is assumed to be heterogeneous in the inversion, a consistent representation of the T and S fields is obtained. When the S field is spatially heterogeneous but is assumed to be homogeneous in the inversion, a consistent representation of the T field is still obtained, but the S field is entirely misrepresented; if the S field is actually homogeneous but assumed to be heterogeneous, a poor representation of the T and S fields is obtained along with high uncertainty in the inversion statistics of confidence.
Phosphazenes (2011)
Organophosphorus Chemistry provides a comprehensive and critical review of the recent literature. Coverage includes phosphines and their chalcogenides, phosphonium salts, low coordination number phosphorus compounds, penta- and hexa- coordinated compounds, quiquevalent phosphorus acids, nucleotides and nucleic aicds, ylides and related compounds, phosphazenes and the application of physical methods in the study of organophosphorus compounds. This is the 40th in a series of volumes which first appeared in 1970 under the editorship of Stuart Trippett and which covered the literature of organophosphorus chemistry published in the period from January 1968 to June 1969, citing some 1370 publications. The present volume covers the literature from January 2009 to January 2010, citing more than 2200 publications, continuing our efforts to provide an up to date survey of progress in an area of chemistry that has expanded significantly over the past 40 years.
Publisher's Note: ''Enhanced damping of ion acoustic waves in dense plasmas'' [Phys. Plasmas 18, 014505 (2011)]
No abstract prepared.
Publisher's Note: ''Relaxation model for extended magnetohydrodynamics: Comparison to magnetohydrodynamics for dense Z-pinches'' [Phys. Plasmas 18, 012703 (2011)]
No abstract prepared.
Publisher's Note: ''Higher-order energy-conserving gyrokinetic theory'' [Phys. Plasmas 18, 022305 (2011)]
No abstract prepared.
Erratum: ''New equipment and new technique for measuring activity coefficients and Henry's constants at infinite dilution'' [Rev. Sci. Instrum. 82, 025108 (2011)]
No abstract prepared.
Response to 'Comment on 'The nonmonotonic concentration dependence of the mean activity coefficient of electrolytes is a result of a balance between solvation and ion-ion correlations'' [J. Chem. Phys. 134, 157101 (2011)]
No abstract prepared.
Publisher's Note: ''Temperatures following x-ray free-electron-laser heating of thin low- and medium-Z solid targets'' [Phys. Plasmas 18, 013105 (2011)]
No abstract prepared.
Response to 'Comment on 'Heat capacity, enthalpy fluctuations, and configurational entropy in broken ergodic systems'' [J. Chem. Phys. 134, 147101 (2011)]
We show that Johari's critique of our work is based on a misunderstanding of ergodic theory and a disregard for the broken ergodic nature of glass. His analysis is in contradiction with well established experimental results in specific heat spectroscopy, shear-mechanical spectroscopy, and the vanishing of heat capacity in the limit of zero temperature. Based on these misinterpretations, Johari arrives at the erroneous conclusion that the residual entropy of glass is real. However, we show that Johari's result is an artifact in direct contradiction with both rigorous theory and experimental measurements.
Response to ''Comment on 'Acoustic solitons in inhomogenous pair-ion plasmas''' [Phys. Plasmas 18, 054701 (2011)]
The quantity n{sub p0}(0) is different from n{sub p0}(x) and same is true for v{sub p0}(0), v{sub p0}(x). Taking these differences into account and considering the mathematical relation v{sub p0}(x)= 1/n{sub p0}(x), it can easily be shown that derivatives of these space dependent densities and velocities are linked through the relation {partial_derivative}v{sub p0}(x)/{partial_derivative}{eta}=-1/n{sub p0}{sup 2}(x){partial_derivative}n{sub p0}(x)/{partial_derivative}{eta}. We show that constraint (1) of the comment can also be transformed to derivative transformation relation. This derivative transformation relation can be used in the derivation of the KdV like equation and our model is valid for inhomogenous pair ion plasma. We mathematically and physically prove that the objections in the comment are false and baseless.
Comment on 'Solution of Dirac equation with spin and pseudospin symmetry for an anharmonic oscillator' [J. Math. Phys. 52, 013506 (2011)]
No abstract prepared.
Publisher's Note: ''A Freon-filled bubble chamber for neutron detection in inertial confinement fusion experiments'' [Rev. Sci. Instrum. 82, 033305 (2011)]
No abstract prepared.
Response to 'Comment on 'Threshold voltage control of oxide nanowire transistors using nitrogen plasma treatment'' [Appl. Phys. Lett. 98, 176101 (2011)]
No abstract prepared.