Anne Laraia graduated from the University of Massachusetts Lowell with a grade point average of 3.983 {summa cum laude} earning her bachelor's degree in Atmospheric Science with a minor in mathematics. Anne began doing research in Prof. Gamache's group at the end of her freshmen year. At the end of her sophomore year she was invited by the Centre National de la Recherche Scientifique (CNRS) to work in Paris for a month with researchers at the Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), CNRS and Universités Paris 12 and Paris 7, and with researchers at Laboratoire de Dynamique, Interactions et Réactivité (LADIR), Université Pierre et Marie Curie-Paris 6. The summer after her Junior year she took the position of Visiting Student at the Harvard-Smithsonian Astrophysical Observatory working with scientists at the Center for Astrophysics. Anne will begin her Ph.D. studies at the California Institute of Technology (Caltech) in Pasadena, CA in the Department of Environmental Sciences and Engineering and will pursue research in the dynamics of planetary atmospheres.
Below is a short description of the research, presentations, publications she made as a UML student.  

Research:
           Nitric acid, HNO3, is an important minor constituent in the Earth's atmosphere. It is the main stratospheric reservoir species of the NOX family. Photolysis of gas phase HNO3 releases NO2, enabling a major pathway for the deactivation of chlorine via the reformation of ClONO2 from NO2 and ClO. The Polar Stratospheric Clouds (PSCs) that form in the very low temperatures of polar winter remove HNO3, a key component of PSCs, from the gas phase. PSC particles provide surfaces on which heterogeneous chemical reactions occur that convert chlorine from its reservoir species (e.g., ClONO2, HCl) to the highly reactive forms (e.g., ClO) that participate in the catalytic cycles of ozone destruction. If PSC particles grow large enough they can settle out of the lower stratosphere carrying the HNO3 with them in a process known as denitrification. When denitrification is severe the formation of ClONO2 is limited, allowing enhanced ClO and thus chemical ozone destruction to persist. Thus HNO3 has a major role in both the activation and the deactivation of chlorine and indirectly affects the extent, duration, and cumulative magnitude of stratospheric ozone depletion.
           As a result of the importance of nitric acid's role in the major catalytic cycles for stratospheric ozone loss a number of balloon, aircraft, and satellite instruments are retrieving the concentration profiles of HNO3, for example the Polar Aura Validation Experiment (PAVE); the Microwave Limb Sounder (MLS), High Resolution Dynamics Limb Sounder (HIRDLS), and Tropospheric Emission Spectrometer (TES) experiments aboard the Aura satellite.; JPL MkIV solar occultation Fourier Transform Infrared (FTIR) spectrometer, the Smithsonian Astrophysical Observatory (SAO) far-infrared spectrometer (FIRS-2), and the JPL Submillimeterwave Limb SounderŠ2 (SLS-2), the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on the European Space Agency (ESA) Environmental Satellite (Envisat), the Swedish-led Odin satellite with the Submillimetre Radiometer (SMR), the Improved Limb Atmospheric Spectrometer (ILAS) on board the Advanced Earth Observing Satellite (ADEOS), and the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) on the Canadian Space Agency's SCISAT-1 mission. The HNO3 retrieval is based primarily on a set of microwindows covering the 1690 - 1730 cm-1 spectral range, with additional microwindows in the range 860 - 880 cm-1 used for measurements in the upper troposphere.
           A main weakness of the spectroscopic data is the pressure-broadened half-widths. The focus of Anne's work was to calculate N2 broadened half-widths and their temperature dependence for some 4979 transitions in the v5 band of HNO3 using the Complex Robert-Bonamy (CRB) formalism. This work was done in collaboration with researchers at the Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), CNRS and Universités Paris 12 and Paris 7 and was in support of the MIPAS insturment onboard the European Space Agency (ESA) Environmental Satellite (Envisat). The half-widths determined in this work were scaled to air-broadening by multiplying them by 0.935 and used in simulations. A significant decrease of the residuals in the retrievals was observed.

           Working in collaboration with researchers at the Laboratoire de Dynamique, Interactions et Rèactivité (LADIR), Université Pierre et Marie Curie-Paris 6 and the Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), CNRS, Universités Paris 12 and Paris 7, measurements and calculations of the broadening coefficients of H2CO were made to aid in the reduction of satellite remote sensing data. Anne's work was to use CRB theory to calculate the half-width and its temperature dependence for N2-broadening. Anne made CRB calculations for 3296 v2 transitions at 7 temperatures (200,225,275,296, 350, 500,and 700K). From these data the half-width and its temperature dependence were determined. A line list was prepared and incorporated into the 2010 version of the HITRAN database. These data are needed for the reduction of many of the satellite measurements of H2CO.

           Anne has made calculations of the half-widths, line shifts, and temperature dependence of the half-widths are determined for H216O rotation band transitions. The reasons for choosing the rotation band are that the parameters describing the intermolecular potential are mostly well known, no vibrational effects enter into the calculation, i.e. the S1 term is zero, and accurate wavefunctions can be determined by diagonalizing the Watson Hamiltonian. For this band, there are a good number of measurements of the half-width to which the calculated values can be compared. There are fewer measurements of the line shift and the temperature dependence of the half-width, but still enough to draw conclusions on the calculated values. To make the calculations, all transitions of the (0 0 0) - (0 0 0) band belonging to the principal isotopologue of water, H216O, were selected from the HITRAN database. This procedure yielded 1639 transitions. The half-width and line shift were calculated via the CRB formalism at seven temperatures, 200, 225, 275, 296, 350, 500, 700, for N2 and O2 as the perturbing gas. The air-broadened values were determined at each temperature using the usual formula. Very good agreement with the measurement database is observed.

          Anne is also working on calculating total internal partition sums for new molecules and isotopologues added to the HITRAN database. These molecules include: two minor isotopologues of carbon dioxide (13C18O2 and 13C18O17O), a minor isotopologue of ethane (13C12CH6), two isotopologues of monodeuterated methane (12CH3D and 13CH3D), and carbon tetrafluoride (12CF4). The method used is based on previous work of Gamache et al. Calculations are compared to values in the literature whenever possible, and these data will serve as an update to the 2008 version of the HITRAN database. These calculations will be extended to consider molecules of interstellar and planetary significance. The current list includes propane (C3H8), diacetylene (C4H2), cyclopropene (C3H4), cyanoacetylene (HC3N), cyanogen (C2N2), sulfur monoxide (SO), CS and CS2 molecules, molecular hydrogen (H2), C2HD isotopologue of acetylene, methyl radical (CH3), and H3+. The Q(T) data will be generated at 1 K steps from 1 to 3025 K and a select part of the data will be used in an updated version of the TIPS program.

For a short description of the CRB formalism  click here


Presentations

  • April 29, 2008

Anne Laraia, Robert R. Gamache, "Pressure Broadening Parameters for Nitric Acid in the v5 Band," the 11th Annual Student Research Symposium, The University of Massachusetts Lowell, April 29, 2008

  • June 22-24, 2008

Robert R. Gamache, Anne Laraia, "N2-Broadening of v5 Band Transitions of HNO3 in the Region from 841-931 cm-1," the 10th Biennial HITRAN Database Conference, Harvard-Smithsonian Center for Astrophysics, June 22-24, 200

  • June 22-24, 2008

L. Gomez, H. Tran, A. Perrin, J.-M. Hartmann, J. Orphal, P. Chelin. G. Brizzi, Robert R. Gamache, Anne Laraia, "HNO3 Spectroscopic Parameters in the 600-950 cm-1, and 1300-1360 cm-1, Spectral Regions," the 10th Biennial HITRAN Database Conference, Harvard-Smithsonian Center for Astrophysics, June 22-24, 2008

  • June 22-24, 2008

A. Perrin, D. Jacquemart, F. Kwabia Tchana,, N. Lacome, Robert R. Gamache, Anne Laraia, "Absolute Line Intensities and Accurate Line Broadening Parameters for the 5.7 µm and 3.6 µm Bands of Formaldehyde," the 10th Biennial HITRAN Database Conference, Harvard-Smithsonian Center for Astrophysics, June 22-24, 2008

  • Aug 27-30, 2008

A. Perrin, D. Jacquemart, F. Kwabia Tchana,, N. Lacome, Robert R. Gamache, Anne Laraia, "Absolute line intensities, line-broadening parameters and new linelists for the 5.7 µm and 3.6 µm bands of formaldehyde," 8th Atmospheric Spectroscopy Applications Congress, Université de Reims Champagne Ardenne, Reims, France, 2008

  • Aug 27-30, 2008

L. Gomez, H. Tran, A. Perrin, J.M. Hartmann, J. Orphal, P. Chelin, R.R. Gamache and A. Laraia, "Some improvements of HNO3 spectroscopic parameters in the spectral region between 600 and 950 cm-1," 8th Atmospheric Spectroscopy Applications Congress, Université de Reims Champagne Ardenne, Reims, France, 2008

  • Aug 27-30, 2008

R. Gamache, Anne Laraia , J.-M. Hartmann, A. Perrin, L. Gomez, "Half-widths and Their Temperature Dependence for N2-Broadening of v5 Transitions of HNO3," 8th Atmospheric Spectroscopy Applications Congress, Université de Reims Champagne Ardenne, Reims, France, 2008

  • April 28, 2009

Anne Laraia, Robert R. Gamache, "Pressure Broadening Parameters for Nitric Acid in the v5 Band," the 12th Annual Student Research Symposium, The University of Massachusetts Lowell, April 28, 2009

  • May 1, 2009

A. Laraia, R. Gamache. "Half-widths and Their Temperature Dependence for N2-Broadening of v5 Transitions of HNO3," Statewide Undergraduate Research Conference, University of Massachusetts Amherst, Amherst, MA, 2009

  • April 27, 2010

Anne Laraia, Robert R. Gamache, "Total Internal Partition Functions for HITRAN2008," the 13th Annual Student Research Symposium, The University of Massachusetts Lowell, April 27, 2010

  • April 27, 2010

A. L. Laraia, J. Lamouroux, H. Tran, R. R. Gamache, L. S. Rothman, I. E. Gordon, J.-M. Hartmann, "Updated database plus software for line-mixing effects in CO2 infrared spectra and their test," the 13th Annual Student Research Symposium, The University of Massachusetts Lowell, April 27, 2010

  • June 10, 2010

R. R. Gamache, J. Lamouroux, A. L. Laraia "Complex Robert-Bonamy calculations of Self-, N2-, O2-, and air-broadened line shape parameters of CO2," the 20th International Conference on Spectral Line Shapes, Memorial University of Newfoundland, June 6-11, 2010

  • June 17, 2010

R. R. Gamache, J. Lamouroux, A. L. Laraia, "The Collision-Broadened Line Shape of CO2: the Complexity of Simplicity," the 11th Biennial HITRAN Database Conference, June 16-18, 2010

  • June 17, 2010

A. L. Laraia, R. R. Gamache, J. Lamouroux, Ha, J-M Hartmann, "An Improved Version of the CO2 Line-mixing Database and Software Update and Extension," the 11th Biennial HITRAN Database Conference, June 16-18, 2010

  • June 17, 2010

D. Jacquemart, N. Lacome, A. Laraia, R.R. Gamache, A. Perrin, F. Kwabia Tchana, "Formaldehyde Broadening Coefficients: the 5.7µm AND 3.6µm Bands," the 11th Biennial HITRAN Database Conference, June 16-18, 2010

Publications

J. Lamouroux, H. Tran, A. L. Laraia, R. R. Gamache, L. S. Rothman, I. E. Gordon, J.-M. Hartmann, "Updated database plus software for line-mixing in CO2 infrared spectra and their test using laboratory spectra in the 1.5-2.3 µm region," in press, J. Quant. Spectrosc. Radiat. Transfer, 2010. preprint
A. Predoi-Cross1, W. Liu, R. Murphy, C. Povey, R. R. Gamache, A.L. Laraia, A.R.W. McKellar, D.R. Hurtmans, V. Malathy Devi, "Measurement and computations for temperature dependences of self-broadened carbon dioxide transitions in the 30012 <— 00001 and 30013 <— 00001 bands," J. Quant. Spectrosc. Radiat. Transfer, 111, 1065-1079, 2010. doi 10.1016/j.jqsrt.2010.01.003 PDF of article or JQSRT archive

D. Jacquemart, A. Laraia, F. Kwabia-Tchana, R. R. Gamache, A. N. Lacome, "Formaldehyde around 3.5 and 5.7-µm : measurement and calculation of self- and -N2 broadening coefficients," J. Quant. Spectrosc. Radiat. Transfer, 111, 1209-1222, 2010. doi 10.1016/j.jqsrt.2010.02.004 PDF of article or JQSRT archive

R. R. Gamache and A. L. Laraia, "N2-, O2-, and air-broadened half-widths, their temperature dependence, and line shifts for the rotation band of H216O, J. Mol. Spectrosc. 257, 116-127, 2009. doi 10.1016/j.jms.2009.07.004 PDF of article or J. Mol. Spectrosc. archive
A. Laraia, R. R. Gamache, J.-M. Hartmann, A. Perrin , L. Gomez, "Theoretical Calculations of N2-broadened Half-Widths of n5 Transitions of HNO3," in Press J. Quant. Spectrosc. Radiat. Transfer, 2008. PDF of article or JQSRT archive
L. Gomez, H. Tran, A. Perrin, R. R. Gamache, A. Laraia, J. Orphal, P. Chelin, C. E. Fellows, J.-M. Hartmann, "Some improvements of the HNO3 spectroscopic parameters in the spectral region from 600 to 950 cm-1," In Press, J. Quant. Spectrosc. Radiat. Transfer, 2008. PDF of article or JQSRT archive