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NCAR Annual Scientific Report April 1978 - March 1979 - Link Page Next PART0002 National Center for Atmospheric Research Annual Scientific Report April 1978-March 1979 Submitted to National Science Foundation by University Corporation for Atmospheric Research July 1979 * * iii11 1 CONTENTS INTRODUCTION v ATMOSPHERIC ANALYSIS AND PREDICTION DIVISION 1 Climate Section 7 Oceanography Section 15 Large-Scale Dynamics Section 19 Mesoscale Research Section 28 ATMOSPHERIC QUALITY DIVISION 37 In-Situ Measurements and Photochemical Modeling 39 Biosphere-Atmosphere Interaction 42 Gas and Aerosol Measurements 43 Global Observations, Modeling, and Optical Techniques 45 Reactive Gases and Particles 51 Thermospheric Dynamics and Aeronomy 53 Stratospheric-Tropospheric Exchange 56 Radioactive Aerosols and Effects 58 HIGH ALTITUDE OBSERVATORY 63 Solar Variability Section 65 Solar Atmosphere and Magnetic Fields Section 72 Coronal Physics Section 78 78 Interplanetary Physics Section 83 CONVECTIVE STORMS DIVISION 89 ADVANCED STUDY PROGRAM 113 ATMOSPHERIC TECHNOLOGY DIVISION 127 Research Aviation Facility 129 Computing Facility 141 Field Observing Facility 154 Research Systems Facility 163 Global Atmospheric Measurements Program 169 National Scientific Balloon Facility 176 PUBLICATIONS 183 v INTRODUCTION The UCAR-NSF contract for the operation of NCAR calls for UCAR to submit to NSF an annual scientific report "containing a scientific description of all programs conducted by NCAR staff and NCAR visitors during the previous year." The contract stipulates that the report should "include a description of the scientific problems placed in a larger context, accomplishments, and a listing of papers published." This document is designed to respond to that contract provision, and has as its primary audience those NSF staff members responsible for monitoring UCAR's performance in the operation of a national laboratory under NSF sponsorship. For each division of NCAR, we first present an overall statement of strategies, objectives, and major problems and tasks of the past year, followed by more detailed reports of the activities of the groups within those divisions. The report is intended to show the overall design of NCAR scientific and facilities programs and to give a general descrip- tion of program activities. The purpose is to allow perceptions to be formed of the ways in which programs and activities described in the Program Plan for the upcoming year are linked to NCAR's programs and activities of the past year. This document thus stands at a point between our future plans, as described in the Program Plan and in other, longer-range planning docu- ments submitted to NSF, and two more detailed kinds of documents on NCAR's current and past work. These are, first, scientific publications and technical reports, which are listed in this document; second, the documents prepared for the review panels of the Scientific Programs Evaluation Committee (SPEC), which reports simultaneously to UCAR and to NSF. The SPEC process, which covers all NCAR activities on a three-year schedule, constitutes a rigorous, in-depth review of NCAR performance. This report reflects the many modes of activities at NCAR: collab- orative work among NCAR scientists and university colleagues; the work of individuals and small groups clustered around a central theme; major organized research efforts requiring extensive field experiments; direct facility support to university and other outside scientists; participa- tion in and support of national and international atmospheric research efforts; improvement, development, and deployment of advanced computing capabilities and observing and data-handling techniques and resources; and a wide variety of techniques for bringing together atmospheric scientists on national and international scales to assess the state of knowledge in given areas of atmospheric science, to identify promising paths for future research, and to allow scientists to determine how their own research interests fit within the mosaic of scientific work required to attack the major fundamental problems presented us by the atmosphere. vi Our challenge is to maintain healthy balances among current collab- orative projects and the work of individuals that prepare us for future collaborations; between research and facilities activities; and between development of capabilities and services to meet current needs. We are mindful of the practical need for knowledge of the atmosphere to assist in enabling us to live in harmony with our atmospheric environ- ment, and at the same time, the vast amount of fundamental work that lies between us and the greatest usefulness of atmospheric knowledge. Francis P. Bretherton, Director John W. Firor, Executive Director ATMOSPHERIC ANALYSIS AND PREDICTION DIVISION OVERVIEW OF RESEARCH ACTIVITIES Introduction The Atmospheric Analysis and Prediction (AAP) Division is composed of four sections with specific research interests in climate, ocean- ography, large-scale atmospheric dynamics, and mesoscale phenomena, as shown in the following table of organization: Atmospheric Analysis and Prediction Division (Leith) * Climate Section (Dickinson) Climate Sensitivity Group (Kellogg) Empirical Studies Group (Newton) Global Climate Modeling Group (Washington) * Oceanography Section (Holland) * Large-Scale Dynamics Section (Kasahara) * Mesoscale Research Section (Lilly) A general description of the AAP research directions was provided in the Annual Scientific Report last year. In this first section of the report this year we describe some shifts in emphasis and some high- lights of research activities during the year. In the following sections more detailed descriptions of research activities and directions are provided by the staff. Of course, the final measure of research progress is provided by the list of publications, but these lag behind current research activities by a year or so. Climate Research Climate research in AAP is directed toward the second objective of NCAR and of the Global Atmospheric Research Program (GARP), i.e., the understanding of the dynamics of the climate system. Climate system research is a major component of the U.S. National and the World Climate programs to be carried out in the 1980s. The AAP climate research effort is intended to complement that in the university community. It concentrates on studies of the physical process to which the climate is sensitive, the proper treatment of these processes in a global general circulation model (GCM) suitable for climate studies, and the analysis of climatological data sets to provide an observational basis against which the model climate may be compared. Climate Processes The energy budget of the earth is largely determined by the radi- ative properties of the atmosphere and the surface. Basic improvements are being made in the calculation of the interaction of radiation with 2 AAP Division particles, and they are permitting more accurate treatments of the climatological effects of dust, clouds, and snow albedo. Improved treatment of the absorption of radiation by CO2 is increasing confi- dence in estimates of the sensitivity of climate to C02 changes. The interaction of clouds and radiation is being studied through an analysis of satellite radiance signals. Zonally symmetric energy balance models have served a useful role in the study of climate sensitivity questions, but attention is now turning to more realistic asymmetric models. Observational Studies Further progress has been made during the year on the determination of the unpredictable climate noise in midlatitudes and the identifi- cation of potentially predictable signals of climate variability above the noise level. Large-scale patterns are being examined for improved signal-to-noise ratio. The structure of a westward-propagating planetary Rossby wave with wavenumber one has been determined. The consequences of its interaction with standing wave components are being studied. Further studies are elucidating the details of a large-scale, slowly changing component of atmospheric circulation and its associ- ation with anomalies in sea surface temperature and sea ice. General Circulation Model (GCM) The third-generation GCM has been shown in preliminary tests to provide a much more realistic simulation of the temperature and wind structure of the atmosphere than did the second-generation model. The model contains a far more careful treatment of solar and infrared radiation, clouds, and land surface processes. The effects of soil moisture and vegetation on albedo and evapotranspiration are included. A floating sea ice model suitable for coupling to the GCM has been developed and work is progressing on an ocean circulation model. The inclusion of many new physical processes in the model now permits experiments to determine the sensitivity of model climate to these processes. Emphasis is now shifting toward the carrying out of these experiments in collaboration with colleagues in the university community. Further progress has been made in developing the appropriate methodology so that statistical significance will be clearly known. Attention here is turning to the determination of the statistical significance of perceived changes in climate variances which, depending on their magnitude, may have greater socioeconomic impact than do changes in climate means. AAP Division 3 Oceanographic Research The ocean plays an important role as a regulator of climate. A large part of the heat transport from the equatorial regions towards the poles that is needed to maintain the energy balance of the globe takes place
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