Dr. Chu explores advanced spectroscopy principles, develops new lidar technologies, and studies the fundamental physical and chemical processes that govern the structure and dynamics of the whole atmosphere. She is a Fellow of CIRES that is funded by CU and NOAA, and an Associate Professor in the Department of Aerospace Engineering Sciences. She teaches graduate classes of spectroscopy and lidar remote sensing, and undergraduate classes ASEN 3300 "Electronics and Communications" and ASEN 3113 "Thermodynamics and Heat Transfer".
Xinzhao Chu and her research group focus on both lidar technology development and atmospheric/space science study. The technology development involves atomic, molecular and laser spectroscopy, lidar technology and instrument development, and cluster remote sensing technology applications including observational campaigns from the North Pole to the South Pole. The science study is currently focused on the polar mesospheric and stratospheric clouds, thermal structure and dynamics in the stratosphere, mesosphere and lower thermosphere in both polar and equatorial regions with observations, data analysis, and modeling. One of the goals is to send a resonance lidar into space to study the global middle atmosphere dynamics.
Lidar marathons in Antarctica and plasma-neutral atmosphere coupling
Discoveries of thermospheric neutral iron (Fe) layers (Chu et al., Geophys. Res. Lett., 2011), solar effects on Fe layer bottomside (Yu et al., J. Geophys. Res., 2012), persistent inertia-gravity waves (Chen et al., J. Geophys. Res., 2013), and super-exponential growth of thermal tide amplitude above 100 kilometers (Fong et al., J. Geophys. Res., 2014) by lidar observations in Antarctica are challenging our understanding of electrodynamics, neutral dynamics, chemistry, composition, and energetics in Earth’s geospace environment. CIRES students Zhibin Yu and Weichun Fong in the Chu research group are developing numerical models to study the mechanisms. We achieved initial success, having successfully modeled the thermospheric Fe layers after carefully considering the neutral-plasma coupling and the influences of polar electric field, vertical wind, and aurora activity (see figure). These science discoveries are motivating the atmosphere and space science community with a new initiative, Observatory for Atmosphere Space Interaction Studies (OASIS).
This also has been a year of setting records. The CIRES lidar team set a historic record for lidar observations: a continuous 174 hours of observations from Dec. 29, 2013, to Jan. 6, 2014, in Antarctica. CIRES student Cao Chen set new records, making continuous, sole-operator, 53- and 65-hour lidar observations in the harsh Antarctic winter. CIRES student John Smith and CIRES researcher Wentao Huang achieved lidar signal levels of 2,400 counts per shot at Boulder, Colorado. These long and very high-resolution data sets are invaluable in pushing the envelope of upper atmosphere sciences. Another unprecedented record: CIRES students in the Chu group have won prizes every year from 2009 to 2014 in the Coupling, Energetic, and Dynamics of Atmospheric Regions (CEDAR) Student Poster Competition— most recently Zhibin Yu in 2013 and Weichun Fong in 2014. CIRES researcher Xian Lu won a CEDAR grant as the principal investigator for the first time. Congratulations to these creative students and researchers!
"Members" of the lidar team (from left to right: Cao Chen, Xinzhao Chu, and Jian Zhao) deployed in the summer of 2013–2014 at McMurdo, Antarctica.
Thermospheric iron (Fe) layers (top) discovered by lidar observations on May 28, 2011, at McMurdo, Antarctica (Chu et al., Geophys. Res. Lett., 2011) have been successfully modeled with a new thermospheric Fe/Fe+ model (middle and bottom) through the coupling between Fe+ and Fe layers in the polar geospace (Yu and Chu, J. Geophys. Res., 2014).
CIRES Ph.D. students Cao Chen and Jian Zhao jump up at Arrival Heights Lidar Observatory near McMurdo, Antarctica, to celebrate an extremely successful summer season and Chen's qualification to winter-over in 2014.