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NCAR Annual Scientific Report Fiscal Year 1985 - Link Page Next PART0002 National Center for Atmospheric Research Annual Scientific Report Fiscal Year 1985 Submitted to National Science Foundation by University Corporation for Atmospheric Research March 1986 iii CONTENTS INTRODUCTION ............... ............................................. v ATMOSPHERIC ANALYSIS AND PREDICTION DIVISION ............... 1 Significant Accomplishments........................ 1 AAP Division Office................................................ 4 Mesoscale Research Section . ........................................ 8 Climate Section........................................ 15 Large-Scale Dynamics Section....................................... 22 Oceanography Section. .......................... 28 ATMOSPHERIC CHEMISTRY DIVISION................................. .. 37 Significant Accompl i shments........................................ 38 Precipitation Chemistry, Reactive Gases, and Aerosols Section. ..................................39 Atmospheric Gas Measurements Section............................... 46 Global Observations, Modeling, and Optical Techniques Section.............................. 52 Support Section.................................................... 57 Di rector' s Office. * . ...... .......... .. .. ** 58 HIGH ALTITUDE OBSERVATORYY .. .................. ............... 63 Significant Accomplishments .......... .............................. 63 Coronal/Interplanetary Physics Section ....................... 64 Solar Variability and Terrestrial Interactions Section........................................... 72 Solar Atmosphere and Magnetic Fields Secti on. ................................. 82 ADVANCED STUDY PROGRAM............................ ........ 91 Significant Accompi shment........................................ 91 Visitor Program . ........................ 91 Environmental and Societal Impacts Group......................................... 96 Natural Systems Group................................. 100 CONVECTIVE STORMS DIVISION............. ........ ........... 107 Significant Accomplishments.............. ............ .............. 107 Mesoscale Convective Systems....................................... 109 Thunderstorm Water Budgets and Precipitation....................... 115 Thunderstorm Hydrometeor Evolution--Hail Growth and Trajectory Studies .. ......... .............................. 122 Thunderstorm Electrification.....c...... .................. .1.... 131 Cumulus Cloud Systems: Cumulus-Topped Boundary Layers, Gravity Waves, and Convective Initiation .......... .... 133 iv Cumulus Cloud Systems: Entrainment and Mixing, Cloud Droplet Spectra, and Downdraft Initiation ............... 137 Selected Topics in Microphysics .. ............................ 141 SCIENTIFIC COMPUTING DIVISION ......................................... 147 Significant Accomplishm ents. ....................................... 147 Organization. ........................................ .150 FY 85 Computing Support Provided..... .............................. 151 Systems Section....................................................154 Computer Operations and Maintenance Section........................ 157 User Services Section.............................................. 158 Advanced Methods Section.......1....................... 162 Data Support Section. ................................ 164 ATMOSPHERIC TECHNOLOGY DIVISION ........................................... 181 Statement of Goals ................ o............. ........... 181 Significant Accomplishments. ............ ........................... 181 Organization ....................................................... 183 Research Aviation Facility......................................... 183 Fielod Observing Facity................ ..................... 203 Global Atmospheric Measurements Program..................... 213 Research Applications Program. ...... ............ 216 Design and Fabrication Services................................ 221 ACID DEPOSITION MODELING PROJECT..................................2.... 225 Significant Accomplishments......... ................... .226 Chemistry ........................................... ........ 226 Meteorol ogy .......... ................... ... ................... 229 System Integration and V alidation.............................231 Engineering Model s........................................ 232 PUBLICATIONS. ........ ................... ............... 237 v INTRODUCTION This concise but comprehensive report has a double purpose. First, it is intended to give our Federal sponsor, the National Science Foundation, an accounting of the programmatic results of the support NSF and other agencies provided during the year. Second, it is intended to be a reference document for our colleagues in the universities and elsewhere about the recent work of groups and individuals at NCAR. As most readers know, NCAR has three major types of activity: * We carry out pioneering research work, often in collaboration with colleagues in the atmospheric sciences community, on problems of national and international importance and scope. * In consultation with the community, we develop and provide to the community those computational and field facilities that are most needed to make progress on critical problems and that are of such size and complexity that they are not likely to be within the resources of a single university. * By virtue of the nature of the institution and the breadth and quality of the staff, we offer a place where national and international planning groups may naturally come together to discuss promising research paths and to plan collaborative programs to make progress toward important atmospheric research objectives. This report gives new evidence that not only NCAR, but the entire community, is involved in a wide spectrum of research activities that are important to the science and to the nation. We are involved in questions such as the impact of human activity on the climate; the detailed processes by which acid rain is formed; the possibility of season-ahead climate pre- diction; the interaction of social, economic, and political forces in the African droughts; the detailed behavior of the sun and the reasons why its output varies; the role of electricity in thunderstorms; and the way groups of thunderstorms mass together to produce some of our most severe and damaging weather. In terms of basic and applied research, our work covers an equally broad spectrum. Though the bulk of our work is nearer the basic end of this spectrum, our work this past year ranged from fundamental studies of turbulence to the meteorological aspects of aircraft safety, and from studies of the ancient atmosphere to the development of models of acid deposition designed to be helpful to regulatory agencies. Like many endeavors supported by public funds, atmospheric research will be constrained by budget pressures for several years to come. NCAR will continue to be a resource for community progress, regardless of budget vi level. We are shaping our programs so that, in concert with the community, NCAR can continue to produce valuable research results and to provide essential facilities to the community. Our continuing aim is to contribute to the store of fundamental knowledge most needed by decision- and policy- makers in their efforts to foster the economic and environmental well-being of the nation and the world. As it does every year, this report demonstrates that NCAR's greatest asset is its staff, who consistently adhere to high standards of perform- ance and dedication. Again my heartfelt thanks go to them. My thanks also go to the many colleagues in the atmospheric sciences community who have worked with us and have contributed much time and effort to advising us, helping us shape our objectives, and reviewing our programs. Wilmot N. Hess Director ATMOSPHERIC ANALYSIS AND PREDICTION DIVISION Scientists in the Atmospheric Analysis and Prediction (AAP) Division study the behavior of the atmosphere and oceans on scales of motion ranging from small-scale turbulent eddies with lifetimes of seconds to global-scale circulations with time scales of years or longer. Investigations of turbu- lence, planetary boundary layers, convective storm systems, regional-scale meteorology, ocean circulations, extended-range weather prediction, and cli- mate are pursued through a balance of theoretical, numerical modeling, and observational studies. Advances in the fundamental understanding of atmo- spheric and oceanic processes make it possible to answer many important ap- plied problems, such as those related to seasonal forecasts, climate change due to increasing trace gases and modification of land surfaces, acid deposi- tion, and prediction of severe weather phenomena. In addition to performing individual research and collaborating with visitors and scientists in universities and other research institutions from around the world, AAP scientists participate actively in the planning and exe- cution of national and international scientific projects, such as the Earth Radiation Budget Experiment (ERBE), the National Stormscale Operational and Research Meteorology (STORM) Program, the First ISCCP Regional Experiment (FIRE; ISCCP denotes International Satellite Cloud Climatology Program), the Tropical Ocean Global Atmospheric (TOGA) Programme, the Global Tropospheric Chemistry Program, the Department of Energy's (DOE) Carbon Dioxide Research Program, and the World Ocean Circulation Experiment (WOCE). AAP scientists are also active in serving on national
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