A STUDENT TEAM INVESTIGATES AEROSOL PARTICLES, SNOW CRYSTALS, SNOWFALL AND CLOUD CHEMISTRY IN THE NORTHERN COLORADO ROCKIES, JANUARY 2003

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1 A STUDENT TEAM INVESTIGATES AEROSOL PARTICLES, SNOW CRYSTALS, SNOWFALL AND CLOUD CHEMISTRY IN THE NORTHERN COLORADO ROCKIES, JANUARY 2003 Introduction Through field studies, science and engineering students can expand education and training received in the classroom and laboratory. Accordingly, Hindman (1993, Bull. Am. Meteor. Soc.) developed a field course for City College of New York (CCNY) students at Storm Peak Laboratory (SPL) located at 10,520 feet MSL in the northern Colorado Rockies near Steamboat Springs. The course was an outgrowth of the research he and his colleagues were conducting on the physical and chemical properties of the snowing clouds that frequently enveloped the lab. This field course and the tradition of geological field courses in the CCNY Earth and Atmospheric Sciences Department led to a required environmental project course for all EAS undergraduate students. The course you will read about in this volume is Prof. Hindman's expression of the course. The reports for the 2001 and 2002 courses at SPL are at SPL was established 22 years ago (Hindman, 2001, Weatherwise) and has been developed into a world-class facility by the Desert Research Institute (DRI) of the University of Nevada (Borys and Wetzel, 1997, Bull. Am. Meteor. Soc.). The facility, thus, is thoroughly equipped for student studies. Further, its easy accessibility atop the Steamboat ski area makes SPL attractive to adventuresome students. SPL stormpeak.dri.edu Ice-encrusted SPL after a significant cloud immersion. The wave cloud, in the background, was triggered by the Park Range, upon which SPL is located. SPL Base (the Leisure Resorts at Steamboat) in the valley below SPL. Lowenthal, et al. (2002, J. Geophys. Res.) and Hindman, et al. (2002, J. Wea. Modif.) have demonstrated the sensitivity of the clouds at SPL to air pollutants. So, SPL is an excellent location for students to study the effects of air pollutants on clouds. The effects studied in the clouds that envelop SPL no doubt occur in the clouds above NYC. Air pollution affects both the physical and chemical properties of clouds. Consequently, Prof. Teresa Bandosz of the CCNY Chemistry Department and Prof. Neal Introduction page 1

2 Phillip of the Bronx Community College (BCC) Department of Chemistry and Chemical Technology joined with Prof. Ward Hindman, a cloud physicist, to conduct the course. Teresa is a specialist in the measurement of atmospheric pollutant gases and Neal specializes in measurement of pollutants in water samples, both atmospheric and domestic. Neal was an undergraduate meteorology and chemistry major at CCNY and was the first CCNY student Ward brought to SPL in the Spring of In January 2001, Neal brought his first student to SPL to study. Thus, the third-generation researcher has arrived at SPL. Course summary During the Fall semester 2002, the CCNY and BCC students planning to study at SPL between 6 and 19 January 2003 learned about the experiments to be conducted and were trained on the CUNY instruments to be brought to SPL. The education and training occurred in a series of seminars during "club hours" when no classes were scheduled. Additional training occurred during the three-day acclimatization period upon arriving in Steamboat Springs. SPL Base (SPLB) was the condominium that housed students and staff at the 6,700 foot MSL base of the Steamboat ski mountain. To facilitate movement between SPL and SPLB, the students had ski lessons during the day. They trained on the instruments in the evenings at SPLB. After acclimatizing, the students collected data at SPL and SPLB every-threehours around-the-clock for a 7-day period (1100 MST, 10 January to 0800 MST, 18 January 2003). This required the students to work as a team and in shifts. Cloud and snow samples were collected at SPL and snow samples at SPLB and their ph measured. Also, the students operated SO 2 and NO 2 gas and aerosol particle instruments at SPL and at SPLB to measure the concentrations of air pollutants. A weather station and particulate instruments operated automatically at 8,500 feet MSL on the ski area to produce a vertical distribution of weather and air pollutants between SPL and SPLB (called SPL Mid-mountain, SPLM). The data were inspected for quality in the field and the intensive data analyses were conducted during the Spring Semester 2003 at CCNY and BCC. During the Spring Semester 2003, the CCNY and BCC students studied at their respective campuses. CCNY EAS post-baccalaureate student Noel Hennelly studied independently with Prof. Hindman. Noel took the Environmental Field Studies course at SPL last year and was a great help to the new students. CCNY EAS graduate students Mari Wee and Martin Yapur studied in the Environmental Project course with Prof. Hindman. Daidre Nembhard, now at Lehman College, studied last year at SPL and returned this year to help Prof. Phillip with his BCC undergraduate students Cheryl Gulliver, Nelson Suero and Roberto Garcia. Prof. Bandosz and her graduate student Deon Hines were responsible for teaching all how to make the trace-gas measurements. Introduction page 2

3 The CCNY and BCC students jointly reported their findings at an EAS Department seminar at the end of the semester and their reports constitute the body of this volume. Volume summary The student team studied atmospheric physical and chemical phenomena at SPL. Detection of aerosol particle nucleation events led to analyses of aerosol formation and growth by Maria Wee. She identified the formation of ultrafine condensation nuclei caused the events and she made progress toward detecting the growth of these particles; such growth has been reported in other parts of the world. Observations of snow crystal habits during a warmer and a colder snowfall event led to a study of crystal formation conditions by Noel Hennelly. She produced beautiful images of the crystals, found the crystal formation conditions were consistent with accepted knowledge and proposed a new method of inferring and elusive cloud property, supersaturation (relative humidity >100%). Satellite overflights during snowfall events led to a study of the measurement of snowfall rates from space by Martin Yapur. The space-borne measurements detected 58% of the SPL snowfall events and produced greater water-equivalent precipitation amounts. Recommendations are made to reduce these discrepancies. Cloud and snow samples, returned frozen from SPL, were chemically analyzed by C. Gulliver, R. Garcia and N. Suero. The first-ever mercury measurements in the SPL cloud an snow samples were unexpectedly high and, thus, warrants further investigation. Finally, NO 2 and SO 2 gas measurements were analyzed by D. Hines. These data were included in the SPL archives to assist possible future studies. Acknowledgements Financial support which covered the rental of SPL and SPLB, shipping, supplies and student stipends was received from: The PSC-CUNY Research Award program The CCNY {EAS Department (J. Steiner), Science Division (M. Tamargo), Office of Student Affairs (J. Hendricks), the NSF-AMP program (J. Barba) and the NASA- PAIR program (R. Khanbilvardi)} The BCC {Office of Academic Affairs (M. Keizs), Student Activities (K. Daley) and President's Office (C. Williams)} Essential support in Steamboat Springs was received from: The DRI Storm Peak Laboratory (R. Borys) The Steamboat Ski and Resort Corporation (M. Lane, C. Wiedemer, B. Rommich) The Leisure Resorts (S. Everett, G. Toma) Dr. David Banks (SPLB trailer) ACZ Laboratories, Inc. (B. Craig) Mr. Tom Breckenridge of Mesa CO (Class assistant) TSI of St. Paul, MN loaned a DustTrak instrument for use at SPL. The Brompton Collection of NYC, NY provided hand and foot warmers and blankets to SPL. Introduction page 3

4 SPL Scenes (all photos by Prof. Hindman unless otherwise noted): Maria Wee checking the aerosol particle measuring instruments at SPLM. Noel Hennelly being interviewed by Fox 5 NYC weather person Nick Gregory at SPL as part of the Steamboat "Weather Summit". At SPL, Martin Yapur (left) being instructed by Prof. Neal Phillip on ph and conductivity measurements of cloud and snow samples collected at SPL and snow samples collected at SPLB. Deon Hines (center) helping Maria with the gas measurements at SPL while Nelson Suero records weather observations. A well-protected Daidre Nembhard making wind speed measurements during a cloud sieve exposure to collect cloud water samples at SPL. Cheryl Gulliver recording weather observations, with the help of Nelson, at SPLB (photo by Prof. Phillip). Introduction page 4

5 Roberto Garcia preparing the SPL snowfall collector (photo by Prof. Phillip). Prof. Teresa Bandosz (left) "shepherding" Deon (center) and Martin (right) between SPL and SPLB during an early-morning shift-change. Before the students arrived in Steamboat Springs, Tom Breckenridge (left) and Dr. Randy Borys, SPL Director, prepared a load of SPLB instruments from storage at Dr. Bory's office in Steamboat. Prof. Ward Hindman giving Maria a ride from SPL to the top of the gondola for her down-load during an early-morning shift-change between SPL and SPLB. Introduction page 5