1 / 26

Annual Committee Meeting Taryn M. Lopez May 8, 2008

Annual Committee Meeting Taryn M. Lopez May 8, 2008. Environmental Chemistry Program University of Alaska Fairbanks Department of Chemistry & Biochemistry. Committee Members. Cathy Cahill: Dept. of Chemistry/UAF Geophysical Institute/AVO

ojal
Download Presentation

Annual Committee Meeting Taryn M. Lopez May 8, 2008

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Annual Committee Meeting Taryn M. Lopez May 8, 2008 Environmental Chemistry Program University of Alaska Fairbanks Department of Chemistry & Biochemistry

  2. Committee Members Cathy Cahill:Dept. of Chemistry/UAF Geophysical Institute/AVO Specialties: Atmospheric chemistry, atmospheric aerosols Cindy Werner: USGS Volcano Emissions Project, Project Chief Specialties: Volcanic gas chemistry, monitoring of volcanic emissions Jon Dehn: UAF Geophysical Institute/AVO Specialties: Physical volcanology, remote sensing of volcanoes Bill Simpson: Dept. of Chemistry/UAF Geophysical Institute Specialties: Physical and atmospheric chemistry, spectroscopy Rainer Newberry: Dept. of Geology and Geophysics Specialties: Geochemistry, genesis of ores, exploration of ore deposits

  3. Why study volcanic gases? Volcanic gases can provide insight into subsurface volcanic processes through their chemical signatures: • Magma solubility • Water solubility • Pressure/Temperature • Oxidation state By collecting repeated gas measurements over time scientists can use these chemical signatures to elucidate subsurface processes and help forecast volcanic activity.

  4. Research Goals 1) Use the chemical signatures of volcanic gases to elucidate subsurface volcanic processes 2) Utilize, expand on, and validate ground and satellite-based remote sensing techniques for volcano monitoring to make it safer and more efficient for scientists to measure volcanic gases 3) Investigate the atmospheric evolution and fate of volcanic gases, specifically how volcanic gases react in the atmosphere and what the implications of these reactions are with respect to volcano monitoring and the environment

  5. Current Projects • Chemistry and emission rates of volcanic gases from Bezymianny volcano, Kamchatka (Contribution to PIRE project) • OMI (Ozone Monitoring Instrument) validation for high latitude volcanic sulfur dioxide emissions Image produced by Dimitry Melnikov

  6. I. Bezymianny Gas Chemistry Project goals: • Collect repeated direct and remote measurements of Bezymianny’s volcanic emissions over 3-4 field seasons • Ground (and air) based remote sensing of plume SO2 (and BrO?) column densities using UV spectroscopy (FLYSPEC) • Direct sampling of volcanic gases from dome (and elsewhere?) using evacuated (Giggenbach) bottle technique • Use these data (and geochemical modeling software?) to deduce subsurface environmental conditions • Compare gas chemistry with seismic, deformation, and petrologic data to generate a model explaining Bezymianny’s volcanic system (PIRE Project Goal)

  7. Bezymianny Sample Locations, 2007 ASTER image from 2/4/2007

  8. I. Bezymianny Gas Chemistry Methods: FLYSPEC Giggenbach Bottles

  9. www.oceanoptics.com Figure from Keith Horton FLYSPEC Specifications • Ocean Optics USB2000 UV Spectrometer, integrated GPS & data processing software • Measures light intensities from 177 to 330 nm at 0.25 nm spectral resolution • Software uses SO2 absorption feature from 300 – 315 nm, as well as clear sky, and plume FLYSPEC measurements to calculate SO2 column densities, according to Beer’s Law

  10. FLYSPEC Theory I(λ) = transmitted radiation Io (λ) = incident radiation σ = molar absorptivity n = concentration l = pathlength of plume Beer’s Law: ln (Iλ / Ioλ) = - σλnl

  11. Giggenbach Sampling Direct samples were collected using 300 ml pre-weighed, evacuated bottles (Giggenbach bottles) containing a 4 M KOH and Cd(CH3COOH)2 absorbing solution

  12. I. Bezymianny Gas Chemistry Preliminary Results: FLYSPEC Giggenbach Bottles

  13. II. OMI Validation for Volcanic SO2 Project Goals: • Compare direct and ground/air-based remote sensing SO2 measurements from high latitude volcanoes to OMI SO2 product 2) Determine strengths and weaknesses of OMI product for high latitude volcano monitoring and formulate method to make data comparable

  14. OMI Background/Specifications • Flown on the EOS-Aura Spacecraft • Aura was launched on July 15, 2004 • Daily global coverage (14 orbits) • 2600 Km swath width • 13 x 24 Km spatial resolution at nadir • Hyperspectral UV/VIS spectrometer • Measures solar backscatter radiation • 1560 wavelength bands from 270-500 nm with a spectral resolution of 0.5 nm • Measures trace gases including: O3, NO2, HCHO, BrO, OClO, and SO2 • Also measures aerosol characteristics, cloud top heights, cloud coverage, and surface UV irradiance. Schobert et al., 2006 & Ahmad et al., 2003

  15. II. OMI Validation for Volcanic SO2 Preliminary Results: Fourpeaked Case Study Gas flight data provided by USGS-VEP Image produced by Simon Carn

  16. II. OMI Validation for Volcanic SO2 Current work: • Compare OMI SO2 product to USGS-VEP gas flight measurements for Fourpeaked and Augustine 2006 eruptions • Compare OMI SO2 product to ground-based measurements at Bezymianny and other volcanoes (Shiveluch? Stromboli?) • Attended OMI Workshop led by Simon Carn (University of Maryland Baltimore County & NASA Goddard Space Flight Center) at the Cascades Volcano Observatory (Feb. 2008) • Obtained IDL code to produce images and calculate SO2 mass

  17. Future Work • Continue measurements at Bezy; expand sampling techniques to get a more thorough dataset (Stream sampling? Sublimates? BrO absorption?) • Compare OMI to gas measurements (continue work on Fourpeaked and Augustine 2006 VEP measurements) • Obtain funding to for gas sampling instrumentation (electrochemical sensors/infrared analyzers) and field money to conduct aerial traverse of plume to: 1) validate OMI and 2) see how gases evolve with time (homo & heterogeneous reactions & formation of aerosols)

  18. First Year Highlights Spring 2007: TA for Chem 106; took Environmental Geochemistry, IR Remote Sensing; Accepted into PIRE program Summer 2007: Participated in PIRE program (PK, Bezymianny, CVO/MSH), collected gas measurements from Bezymianny & MSH Fall 2007: TA for Chem 105; took Intro to Geochemistry, Fundamentals of Environmental Chemistry; Participated in AVO eruption response at Pavlof Volcano (measured volcanic SO2); Presented preliminary results from Bezymianny SO2 measurements at AGU Fall Meeting Spring 2008: TA for Chem 105; took P-Chem (Quantum Chemistry & Spectroscopy); High Temperature Geochemistry; attended OMI workshop at CVO

  19. Future Work Timeline Summer 2008: Measure volcanic gases at Stromboli (May-June); Shiveluch (July); Bezymianny (July) volcanoes and process data to determine emission rates. Produce OMI images for dates with corresponding ground/air measurements; compare data. Fall 2008: Take P-Chem (Thermodynamics & Kinetics), Intro to Atmospheric Sciences, Chem Seminar; continue data processing & OMI comparison, attend IAVCEI-CCVG Volcanic Gas Workshop (Mexico, November), present on OMI validation results. Spring 2009: Take Remote Sensing of Volcanic Eruptions, Atmospheric Chemistry, Presentation Techniques; Prepare for comprehensive exams. Summer 2009: Comprehensive exams, present proposal; Field work at Bezymianny. Fall 2009: Take Physical Volcanology, continue research. Spring 2010: Take Molecular Spectroscopy, continue research.

  20. Grades Received CHEM 609 Environmental Geochemistry: A GEOS 654 Visible/IR Remote Sensing: A CHEM 605 Fundamentals of Environmental Chemistry: A GEOS 618: Introduction to Geochemistry: A- CHEM 332: Quantum Chemistry & Spectroscopy ? GEOS 695: High Temperature Geochemistry ?

  21. Thank you! Questions?

  22. Discussion Points • Comments on appropriateness of research goals • Suggestions for more effectively meeting goals (new instrumentation, sampling techniques, modeling, etc.) • Bezymianny • OMI validation • Appropriateness of course-selection and modification for degree course requirements • Comments on timeline • Suggestions for 3rd project

  23. Extra Slides…

  24. Gas Flight Traverses 1, 5 & 7 Overlain on OMI Interpolation

  25. 0 DU 4.77 Km 32.8 DU 23.4 Km Traverse 1: Assume Plume Area of 22.8 Km2 For 32.8 DU = 747.84 DU*Km2Pixel Area (not at nadir) = 13 x 42 Km (546 Km2) (assume 0 DU for remainder of Pixel)747.84 DU*Km2 + 0*534DU*Km2 = 546XX = 1.37 DU = Average Pixel ValueOMI Measured SO2 = 0.24 DU

More Related