Community Services

Field Projects

One of ATD’s main functions is the support of field projects, which exemplifies NCAR's community service function. ATD deployment activities serve university users, often involving more than one university. Virtually all of ATD's activities advance the community's observational capabilities. Many university and NCAR scientists regard ATD's capabilities and services as the primary justification for a national center.

In FY 2003, ATD supported the following field projects:

American Low-Level jetS (ALLS)

One of ATD’s MGLASS systems was deployed to Santa Cruz, Bolivia from 15 November 2002 to 28 February 2003 to support Jan Paegle from the University of Utah. The system was used to help define the diurnal and thermodynamic structure of the east Andean Low-Level-Jet (LLJ) and was part of a larger international project involving several South American countries including Bolivia, Argentina, and Paraguay.

The goal of the study was to fill a prominent gap in the monitoring of low level atmospheric jets and to assess their impact on climate variability, regional hydrology, and high impact weather over the Americas, which cannot be resolved by operational observing systems. LLJ circulations promote exchange of atmospheric water vapor and its subsequent condensation and modulate organization of droughts, floods and severe weather over the Americas. ALLS extended efforts to help obtain accurate moisture fluxes over the larger river basins of South America through evaluation of gridded data sets used in empirical studies and calibration of models on both short and long time scales. The GLASS system provided information on wind, moisture, and thermal profiles needed for atmospheric water budget estimations.

Bow Echo and MCV EXperiment (BAMEX)

The Bow Echo and MCV (mesoscale convective vortices) Experiment (BAMEX) took place from 19 May to 6 July 2003 in the central United States. The project focused on lifecycles of mesoscale convective systems, primarily bow echoes and MCVs with the goal of understanding and improving prediction of mesoscale as well as cell-scale processes that produce severe surface winds and heavy rains.

BAMEX was the first field deployment that claimed an entire airport for science operations. Three aircraft, the NRL P3, one of the NOAA P3s and a leased Learjet from Weather Modifications Inc. were operated out of MidAmerica airport near the town of Mascoutah, IL. The two turboprops were equipped with dual Doppler radar capability, the Lear carried the NCAR drop5sonde system to map the mesoscale evolution of long-lived MCSs. On the ground, the GBOS consisting of two mobile GLASS systems and the University of Alabama at Huntsville MIPS system were used to augment airborne radar coverage by documenting the thermodynamic structure of the PBL.

Despite a slow start and lack of appropriate weather in the early weeks of the project, the NLR P-3 with NCAR’s ELDORA radar flew 18 Intensive Observing Periods, spending 134 hours in Midwestern airspace. The MGLASS drove 13,733 miles in the 7 weeks of operations, launching close to 300 sondes, while the Learjet dropped 468 sondes in the same time frame.

Coastal Stratocumulus Imposed Perturbation Experiment (CSTRIPE)

CSTRIPE is a field experiment with collaboration between the California Institute of Technology, CIRPAS (Center for Interdisciplinary Remotely-Piloted Aircraft Studies), Naval Postgraduate School, University of Miami and the National Center for Atmospheric Research (NCAR). CSTRIPE is funded by the National Science Foundation (NSF) and the Office of Naval Research (ONR).

The CSTRIPE field experiment is designed to quantify the effect aerosol has on the microphysics, precipitation and dynamics of marine stratocumulus (MSc). The CIRPAS Twin Otter aircraft was deployed in a three-week mission off the coast of Monterey, California in July, 2003. The strategy is a blend from two previous field experiments, MAST and ACE-2, that were directed towards aerosol-MSc interactions. MAST (Monterey Area Ship Track Experiment) was successful in that it targeted ship tracks. Use of a localized aerosol perturbation, such as ship tracks, obviates the difficulty of separating aerosol-forced signals from meteorologically forced signals. ACE-2 (The second Aerosol Characterization Experiment) was successful in that it used a number of well articulated closure studies to evaluate state-of-the-art models including: hygroscopic and CCN activity of aerosol; cloud activation; the effect of entrainment mixing on the vertical and horizontal distribution of cloud microphysics; and the link between cloud microphysics and the radiative properties of the clouds (i.e. both albedo and bi-directional reflectance used by satellites to retrieve cloud optical properties). By using both a closure strategy, as in ACE-2, and the contrast provided by a localized aerosol perturbation, as in MAST, it is hoped to achieve an unprecedented degree of success with relatively modest resources. A new element added to the strategy is the use of hygroscopic cloud seeding flares as a controlled and well-characterized perturbation.

NCAR’s Multichannel Cloud Radiometer (MCR) was deployed aboard the CIRPAS Twin Otter for all test and research flights. The MCR is a downward-looking seven-channel (2 visible, 4 near-infrared (NIR) and 1 thermal IR) radiometer that scans between ± 45°. The thermal channel will provide cloud top temperature and will therefore be utilized to indirectly estimate cloud top height. MCR visible and NIR channels have been recently analyzed to characterize cloud liquid water content, effective radius, and optical depth [Tschudi, 2002]. It is anticipated that these and other MCR-derived cloud characteristics during CSTRIPE will be included in collaborative work between NCAR [Tschudi] and CIRPAS.

Tschudi, M.A., 2002: Cloud characterization at DYCOMS II from MCR Observations. Proceedings, IEEE Int’l. Geoscience and Remote Sensing Symposium, Toronto, Canada.

Fluxes Over Snow Surfaces II experiment (FLOSS II)

ATD and the University of Wyoming supported Larry Mahrt from Oregon State University for a second field phase of FLOSS. The project took place from December 2002 to April 2003 and focused on the surface meteorology of snow-covered rangeland in the North Park region of Colorado, near Walden.
Preliminary results from FLOSS I conducted in FY 2002 indicated that sage plant communities, which protrude above the snow surface, lead to substantial absorption of solar radiation compared to snow-covered grass, heating of the air and advection of heated air over the cooler snow-covered grass surfaces. The physics of this advection, which leads to a stable internal boundary layer and transport of heat downward towards the snow surface, and the downward heat transport, was addressed by three ISFF systems during FLOSS II.

Instrument Development and Education in Airborne Science (IDEAS) II and III

ATD conducted Phase II and III of IDEAS in FY 2003, in October 2002 and September 2003, respectively. The programs, which involve the NSF/NCAR C-130, have a strong community service impact as they provide opportunities for university students to learn about observational science by testing airborne instrumentation for future NSF airborne deployments. For more information on the educational aspects of IDEAS II and III, visit our Education & Outreach page. For more information on the ATD instrumentation that was tested during this project, visit our Divisional Activities: Technology page.

Land Use and Cloud Interactions Experiment (LUCIE)

LUCIE took place in Costa Rica during the month of March 2003. Two Mobile GLASS were deployed at six pairs of launch sites to determine the relationship between tropical deforestation and the formation of cumulus cloud fields and orographic cloud banks in environmentally complex tropical terrain. In addition, the PIs developed a set of techniques that allows remote sensing observations of convective cumulus and orographic cloud characteristics to be extended to hydrological predictions in regions changing in response to human colonization and agricultural development. At each site, balloon launches occurred every ~3 hours during daylight hours for up to four days before moving the systems to the next pair of sites. The PI for the LUCIE project was Ronald Welsh from the University of Alabama in Huntsville.

TELEX I (or ELLS)

One of NCAR’s GPS dropsonde systems was installed in the NOAA/NSSL GLASS van and used in an upsonde mode during the Electrification and Lightning of Severe Storms (ELLS) and MCS experiment. The project, which took place in Oklahoma from 5 May to 10 June 2003, looked at hypotheses concerning the inter-relationship among the wind field, microphysical characteristics, electrical structure, and lightning of isolated severe storms and of large storm systems. The dropsondes were flown along with an electric field meter to acquire vertical soundings of electric fields, winds and thermodynamic parameters. Balloon soundings of the electric field provided electrical structure of storms throughout the entire vertical extent, which was essential for evaluating all hypotheses concerning the electrification of severe storms and the resulting lightning activity. Up to four balloons were launched into each storm. Combining the electric field meter data and the dropsonde position data gives the electric field sounding the locations of charge regions. The lead PIs on this project were Donald MacGorman, David Rust and Terry Schuur from the University of Oklahoma.

Editorships

Alan Fried

• Guest Editor, Spectrochimica Acta, Special Issue, 2003

Tammy Weckwerth

• Associate Editor, MWR, 1998-present
• Associate Editor, JAS, 2003-present

Steve Cohn

• Associate Editor, Journal of Applied Meteorology

Alan Fried, D. Richter, and J. Walega served in the Outreach program per NSF biocomplexity project: High-Precision Laser-Based Isotopomer Carbon Dioxide Spectrometer. This program involved training of high school teachers and students and will be continued in FY04.

External Scientific, Policy, Educational Committees & Advisory Panels

Alan Fried

• Member, International Advisory Committee, Forth Conference on Tunable Diode Laser Spectroscopy, 2003.
• Member, Laser Applications to Chemical Analysis, International Topical Meetings, 2003-2004.

Jorgen Jensen

• Member, International Commission on Clouds and Precipitation

Cathy Kessinger

• Member, Artificial Intelligence program committee, AMS, 2002-2005.

Wen-Chau Lee

• Member, AMS Radar Committee, 2001-present.
• Chair, Program Committee, 31st Conf. on Radar Meteorology, 2001-2003.

Dirk Richter

• Vice President, Rocky Mountain Chapter of the Optical Society of America, 2003.
• Seminar Coordinator, Advanced Technology and Observing Systems, Atmospheric Technology Division, NCAR.

Britton Stephens

• Member, Carbon Cycle Science Program Ocean Implementation Group, Carbon Cycle Interagency Working Group, 2002-present.

Jeffrey Stith

• Member, International Commission on Clouds and Precipitation

Tammy Weckwerth

• Member, Committee on Measurements, AMS, 2001-present.

Jim Wilson

• Member, WWRP Working Group on Nowcasting, World Weather Research Program, 2003-present.
• Member, NEXRAD Technical Advisory Committee, NEXRAD, 1991-present.
• Member, AMS Radar Committee, AMS, 2000-present.

Workshops

Radar Development and Applications Workshop (23-25 April 2003)
Organized by Wen-Chau Lee, Steve Cohn, J. Vivekanandan
Funded by ATD.

NCAR/NWS Technical Exchange Meeting (22 July 2003)
Organized by Junhong Wang and Dave Carlson
Funded by NCAR.

ECSA's Junior Faculty Forum on Future Scientific Directions (18-20 June 2003)
Organized by Junhong Wang as a co-chair for the "Water Cycle" session
Funded by NCAR/UCAR.

First EUFAR Expert Workshop on Thermodynamics at DLR (December 2002)
Organized by
Funded by Martin Zoeger / DLR.

NSF Community Workshop on Instrumentation for HIAPER (4-6 November 2002)
Organized by Krista Laursen, Dave Carlson
Funded by NSF.

Awards and Patents

Awards

Jim Wilson received the Remote Sensing Lecture Award at the AMS conference in Los Angeles in early February for "outstanding contributions and leadership in the application of meteorological remote sensing."

Patents

Wurman, J., Randall, M., Burghart, C.
U.S. Patent 6,462,699 awarded October 8, 2002
Bistatic radar system for centralized, near-real-time synchronized, processing of data to identify scatterers

Wurman, J., Randall, M., Burghart, C.
U.S. Patent 6,456,229 awarded September 24, 2002
Bistatic radar network having incoherent transmitter operating in a scanning mode to identify scatterers