Physical Sciences and Mathematics Commons^™

Measurements Of Gas‐Phase Inorganic And Organic Acids From Biomass Fires By Negative‐Ion Proton‐Transfer Chemical‐Ionization Mass Spectrometry, P. Veres, James M. Roberts, I. R. Burling, C. Warneke, Joost De Gouw, Robert J. Yokelson

Chemistry and Biochemistry Faculty Publications

[1] Emissions from 34 laboratory biomass fires were investigated at the combustion facility of the U.S. Department of Agriculture Fire Sciences Laboratory in Missoula, Montana. Gas-phase organic and inorganic acids were quantified using negative-ion proton-transfer chemical-ionization mass spectrometry (NI-PT-CIMS), open-path Fourier transform infrared spectroscopy (OP-FTIR), and proton-transfer-reaction mass spectrometry (PTR-MS). NI-PT-CIMS is a novel technique that measures the mass-to-charge ratio (m/z) of ions generated from reactions of acetate (CH₃C(O)O⁻) ions with inorganic and organic acids. The emission ratios for various important reactive acids with respect to CO were determined. Emission ratios for isocyanic acid (HNCO), 1,2 …

What Brown Saw And You Can Too, Philip Pearle, Brian Collett, Kenneth Bart, David Bilderback, Dara Newman, D. Scott Samuels

Biological Sciences Faculty Publications

A discussion of Robert Brown’s original observations of particles ejected by pollen of the plant Clarkia pulchella undergoing what is now called Brownian motion is given. We consider the nature of those particles and how he misinterpreted the Airy disk of the smallest particles to be universal organic building blocks. Relevant qualitative and quantitative investigations with a modern microscope and with a “homemade” single lens microscope similar to Brown’s are presented.

Missoula Greenhouse Gas Emissions Inventory And Analysis, 2003-2008: Toward A Blueprint For Municipal Sustainability, Robin K. Saha, Kathryn Elizabeth Makarowski, Russ J. Paepeghem, Bethany Mason Taylor, Michelle Lanzoni, Michael Lattanzio, Owen Weber

Environmental Studies Faculty Publications

The City of Missoula has been a signer on the U.S. Conference of Mayors Climate Protection Agreement for three mayor administrations, with Mayor John Engen renewing the pledge shortly after he took office in 2006. Mayor Engen and the City of Missoula formed a partnership in January 2009 with The University of Montana and Professor Robin Saha of the Environmental Studies Program to complete an emissions inventory of municipal operations.

The specific goals of the report are:

1. To present a baseline greenhouse gas emissions inventory for the City of Missoula that quantifies total energy use and associated emissions for …

Measurement Of Hono, Hnco, And Other Inorganic Acids By Negative-Ion Proton-Transfer Chemical-Ionization Mass Spectrometry (Ni-Pt-Cims): Application To Biomass Burning Emissions, J. M. Roberts, P. Veres, C. Warneke, J. A. Neuman, R. A. Washenfelder, S. S. Brown, M. Baasandorj, J. B. Burkholder, I. R. Burling, T. J. Johnson, Robert J. Yokelson, J. De Gouw

Chemistry and Biochemistry Faculty Publications

A negative-ion proton-transfer chemical ionization mass spectrometric technique (NI-PT-CIMS), using acetate as the reagent ion, was applied to the measurement of volatile inorganic acids of atmospheric interest: hydrochloric (HCl), nitrous (HONO), nitric (HNO(3)), and isocyanic (HNCO) acids. Gas phase calibrations through the sampling inlet showed the method to be intrinsically sensitive (6-16 cts/pptv), but prone to inlet effects for HNO(3) and HCl. The ion chemistry was found to be insensitive to water vapor concentrations, in agreement with previous studies of carboxylic acids. The inlet equilibration times for HNCO and HONO were 2 to 4s, allowing for measurement in biomass burning …

Timing Of Present And Future Snowmelt From High Elevations In Northwest Montana, Bonnie Jean Gillan, Joel T. Harper, Johnnie N. Moore

Geosciences Faculty Publications

The sensitivity of snowmelt-driven water supply to climate variability and change is difficult to assess in the mountain west, where strong climatic gradients coupled with complex topography are sampled by sparse ground measurements. We developed a model which ingests daily satellite imagery and meteorological data and is suitable for areas >1000 km2, yet captures spatial variability of snow accumulation and melt in steep mountain terrain.We applied the model for the years 2000–2008 to a 2900 km2 snowmelt-dominated watershed in NW Montana. We found that >25% of the basin’s snow water equivalent (SWE) accumulates above the highest measurement station and >70% …

Using Correlation Coefficients To Estimate Slopes In Multiple Linear Regression, Rudy Gideon

Mathematical Sciences Faculty Publications

This short note takes correlation coefficients as the starting point to obtain inferential results in linear regression. Under certain conditions, the population correlation coefficient and the sampling correlation coefficient can be related via a Taylor series expansion to allow inference on the coefficients in simple and multiple regression. This general method includes nonparametric correlation coefficients and so gives a universal way to develop regression methods. This work is part of a correlation estimation system that uses correlation coefficients to perform estimation in many settings, for example, time series, nonlinear and generalized linear models, and individual distributions.

Apparent Seasonal Cycle In Isotopic Discrimination Of Carbon In The Atmosphere And Biosphere Due To Vapor Pressure Deficit, Ashley P. Ballantyne, J. B. Miller, P. P. Tans

Ecosystem and Conservation Sciences Faculty Publications

We explore seasonal variability in isotopic fractionation by analyzing observational data from the atmosphere and the biosphere, as well as simulated data from a global model. Using simulated values of atmospheric CO₂ and its carbon isotopic composition, we evaluated different methods for specifying background concentrations when calculating the isotopic signature of source CO₂ (δ_s) to the atmosphere. Based on this evaluation, we determined that free troposphere measurements should be used when available as a background reference when calculating δ_s from boundary layer observations. We then estimate the seasonal distribution of δ_s from monthly …

Evolution Of Trace Gases And Particles Emitted By A Chaparral Fire In California, S. K. Akagi, J. S. Craven, J. W. Taylor, G. R. Mcmeeking, Robert J. Yokelson, I. R. Burling, S. P. Urbanski, C. E. Wold, J. H. Seinfeld, H. Coe, M. J. Alvarado, D. R. Weise

Chemistry and Biochemistry Faculty Publications

Biomass burning (BB) is a major global source of trace gases and particles. Accurately representing the production and evolution of these emissions is an important goal for atmospheric chemical transport models. We measured a suite of gases and aerosols emitted from an 81 hectare prescribed fire in chaparral fuels on the central coast of California, US on 17 November 2009. We also measured physical and chemical changes that occurred in the isolated down-wind plume in the first similar to 4 h after emission. The measurements were carried out onboard a Twin Otter aircraft outfitted with an airborne Fourier transform infrared …

Laboratory Measurements Of Trace Gas Emissions From Biomass Burning Of Fuel Types From The Southeastern And Southwestern United States, I. R. Burling, Robert J. Yokelson, David W. T. Griffith, T. J. Johnson, P. Veres, J. M. Roberts, C. Warneke, S. P. Urbanski, J. Reardon, D. R. Weise, Wei Min Hao, J. De Gouw

Chemistry and Biochemistry Faculty Publications

Vegetation commonly managed by prescribed burning was collected from five southeastern and southwestern US military bases and burned under controlled conditions at the US Forest Service Fire Sciences Laboratory in Missoula, Montana. The smoke emissions were measured with a large suite of state-of-the-art instrumentation including an open-path Fourier transform infrared (OP-FTIR) spectrometer for measurement of gas-phase species. The OP-FTIR detected and quantified 19 gas-phase species in these fires: CO2, CO, CH4, C2H2, C2H4, C3H6, HCHO, HCOOH, CH3OH, CH3COOH, furan, H2O, NO, NO2, HONO, NH3, HCN, HCl, and SO2. Emission factors for these species are presented for each vegetation type burned. …

Trace Gas And Particle Emissions From Domestic And Industrial Biofuel Use And Garbage Burning In Central Mexico, Ted J. Christian, Robert Yokelson, B. Cardenas, L. T. Molina, G. Engling, S. C. Hsu

Chemistry and Biochemistry Faculty Publications

In central Mexico during the spring of 2007 we measured the initial emissions of 12 gases and the aerosol speciation for elemental and organic carbon (EC, OC), anhydrosugars, Cl(-), NO(3)(-), and 20 metals from 10 cooking fires, four garbage fires, three brick making kilns, three charcoal making kilns, and two crop residue fires. Global biofuel use has been estimated at over 2600 Tg/y. With several simple case studies we show that cooking fires can be a major, or the major, source of several gases and fine particles in developing countries. Insulated cook stoves with chimneys were earlier shown to reduce …

Representation Invariant Genetic Operators, Jonathan E. Rowe, Michael D. Vose, Alden H. Wright

Computer Science Faculty Publications

A genetic algorithm is invariant with respect to a set of representations if it runs the same no matter which of the representations is used. We formalize this concept mathematically, showing that the representations generate a group that acts upon the search space. Invariant genetic operators are those that commute with this group action. We then consider the problem of characterizing crossover and mutation operators that have such invariance properties. In the case where the corresponding group action acts transitively on the search space, we provide a complete characterization, including high-level representation-independent algorithms implementing these operators.

Results From The Ice-Sheet Model Intercomparison Project-Heinrich Event Intercomparison (Ismip Heino), Reinhard Calov, Ralf Greve, Ayako Abe-Ouchi, Ed Bueler, Philippe Huybrechts, Jesse V. Johnson, Rank Pattyn, David Pollard, Catherine Ritz, Fuyuki Saito, Lev Tarasov

Computer Science Faculty Publications

Results from the Heinrich Event INtercOmparison (HEINO) topic of the Ice-Sheet Model Intercomparison Project (ISMIP) are presented. ISMIP HEINO was designed to explore internal largescale ice-sheet instabilities in different contemporary ice-sheet models. These instabilities are of interest because they are a possible cause of Heinrich events. A simplified geometry experiment reproduces the main characteristics of the Laurentide ice sheet, including the sedimented region over Hudson Bay and Hudson Strait. The model experiments include a standard run plus seven variations. Nine dynamic/thermodynamic ice-sheet models were investigated; one of these models contains a combination of the shallow-shelf (SSA) and shallow-ice approximation (SIA), …