This is a CAREER award that will set a solid foundation for a young scientist in developing a successful academic career through creative and exciting research, education, and integrated activities. The focus of the work plan is to advance research and education in lidar remote sensing and the applications of global lidar data to middle and upper atmospheric science. The research represents the first time that worldwide lidar data will be combined to create a global picture of the thermal structure of the mesosphere and lower thermosphere (MLT) via the use of satellite data and computer simulations. These efforts will significantly advance our understanding of the global MLT thermal structure and will further our knowledge of middle atmosphere dynamics that govern these variations. This research will also test and improve sophisticated global circulation models through use of these observational data. Because this project will identify altitudes in the MLT region where the temperatures undergo minimum seasonal variations, it will be important for establishing a temperature baseline that can be used to monitor climate change. This project will significantly advance our knowledge of the least understood region of the atmosphere, which is the equatorial and transition region of the middle atmosphere. This project will also significantly increase the usage of the lidar data collected at Arecibo Observatory, a national facility for scientific research, and at other sites around the world. Through analyzing past and present data, the large data backlog will be reduced, and scientific results will be obtained to help guide future data collection and instrumentation upgrades. The study will act as a bridge to encourage collaborations between modelers and experimentalists to dramatically increase the use of lidar data in testing and improving GCM models. This project provides excellent opportunities to educate and train graduate and undergraduate students, and to advance the integration of atmospheric science with lidar engineering. Students will gain extensive knowledge and experience through classroom learning of lidar remote sensing and then applying them to active lidar research. This project will help the principal investigator to successfully develop her academic career. The activities align well with the PI's career goals of establishing a strong lidar and atmospheric research and education group at the University of Colorado, and developing a center of excellence for lidar technologies and applications for the middle and upper atmosphere community.
", AGS-0645584, was a six-year project at the University of Colorado at Boulder (CU-Boulder). This project set a solid foundation for the PI to developing a successful academic career through creative and exciting research, education and integrated activities. In particular, this project focused on advancing research and education in lidar remote sensing, and the applications of global lidar and satellite data as well as general circulation models to middle and upper atmospheric science. Through six years of efforts, the PI has established a successful academic career. She is leading the world lidar research for the atmosphere and space sciences. Resonance fluorescence Doppler lidar, such as the Na (sodium) Doppler wind and temperature lidars, provide fundamental measurements of the upper atmosphere region from 30-110 km altitude at temporal and spatial resolutions that are difficult to achieve by other means. As a result, Na Doppler lidars have yielded fundamental advances in our understanding of upper atmosphere dynamics, thermal structure, chemistry, and microphysics that were previously impossible. Part of the measuring domain where the Na Doppler lidar systems are particularly capable is the mesosphere and lower thermosphere (MLT), known to be the coldest region in the entire Earth’s atmosphere with minimum temperatures occurring paradoxically in the summer months. This unique condition is a result of wave energy deposition in the upper atmosphere. The lidar measurements of simultaneous, height-resolved, wind and temperatures through the mesosphere and lower thermosphere enable significant advancements in understanding dominant wave momentum and energy transfer processes in the upper atmosphere. The mesosphere and lower thermosphere also defines the reentry region of natural and man-made objects. The existence of a sodium layer, exploited by this lidar technology, is due to meteor ablation and complex atmospheric chemical pathways that lead to a well-defined shell of free metallic atoms surrounding the Earth from 75-110 km. The complex chemistry and dynamic behavior of the sodium gas observed by the lidar contributes to understanding chemical processes in the upper atmosphere. New results are indicating the significant connection between the sodium layer density and plasma processes related to the overlying Earth’s ionosphere. Conversely the lidar systems are providing an improved understanding of upper atmosphere behavior in the reentry region of Earth. The analyses of lidar and satellite data by the research team, and comparison with and then further improvement of sophisticated TIME-GCM and WACCM models, substantially advanced our understanding of the MLT thermal structures, the seasonal and latitudinal variations of MLT temperatures, and gravity wave dynamics. Several new findings were achieved, including the global teleconnection (also called inter-hemispheric coupling) patterns extend well into the thermosphere. The research team demonstrates that in-situ gravity wave generation in the stratosphere by unbalanced flow can be an important gravity wave source, especially during the stratospheric sudden warming. During the project period, the research team developed a new Na Doppler lidar named Student Training and Atmospheric Research (STAR) Lidar. STAR lidar is one of the best lidars in the world because of the highest optical efficiency and lidar signal levels achieved by this lidar. Through the work, the team not only advanced lidar design, development and implementation, but also enabled new science investigations, such as constituent and heat fluxes and potentially eddy flux measurements for the first time. The STAR lidar has become a powerful tool for the community and also a testbed for new lidar technology development. The PI successfully developed a lidar education base in Boulder. She also developed a new curriculum on lidar remote sensing and spectroscopy to systematically educate and train students and your researchers at the University of Colorado and in the CEDAR science community. The PI integrated active research projects with the CU remote sensing classes by involving both graduate and undergraduate students in the research projects and the building of the STAR lidar. Education and training in upper atmosphere science and lidar research is a key aspect of this CAREER project. Data analysis and atmospheric science study, the development, optimization and operation of Na Doppler lidar educated and trained many graduate and undergraduate students as well as a postdoctoral research associate. Over the past 6 years, this project produced 2 Ph.D. degrees (Dr. Chihoko Yamashita in 2011 and Dr. Bo Tan in 2012) and 3 Master degrees (Chihoko Yamashita in 2008, John A. Smith and Bo Tan in 2009). Another three Masters (Brendan Roberts, Ian Dahlke and Johannes Wiig), and two Bachelors (Arvind Talukdar and Aaron Holt) benefited from this project activities. Furthermore, three PhD students (John A. Smith, Weichun Fong and Cao Chen) and one postdoc (Dr. Wentao Huang) gained extensive experience through developing the STAR Na Doppler lidar and launched their careers in lidar research.
