PhD Student Openings

PHD STUDENT SCHOLARSHIPS AVAILABLE

A study on Gravity waves effects in the lower thermosphere from NASA GOLD observations and simulations from WACCM-X

Description: Simulations from the Whole Atmosphere Community Climate Model with Thermosphere and Ionosphere extension (WACCM-X) have shown that a wide variety of gravity waves, ranging from concentric GWs generated by deep convective storms in the tropics to GWs generated by orography, can propagate into the lower thermosphere. The GWs range in horizontal scales from mesoscale to thousands of kilometers and can cause temperature fluctuations ranging from 50-100K. They can produce horizontal wind variations ranging from -60 m/s to +60 m/s and vertical wind variations ranging from 2 m/s to -2 m/s. The O2 and N2 density perturbations caused by such GWs in the thermosphere is likely to be observed by the NASA Global-scale Observations of the Limb and Disk (GOLD) experiment scheduled for launch in January 2018. GOLD can thus provide unprecedented observations of the GW effects on the thermosphere as well as on seasonal and latitudinal variations of GW activity and effects in the thermosphere. Combining high-resolution simulations from WACCM-X and observations from the GOLD mission, this project will study the longitudinal, latitudinal and seasonal variability in GWs observed in the thermosphere. GW amplitudes in temperature and wind perturbations and their sources as well as GW effects on chemical species, specifically O2 and N2 densities in the lower thermosphere will be studied.

An equatorial Cubesat constellation for Regional Ionosphere Mapping

Description: In this project, the PhD student will work on an equatorial constellation mission of eight 6U cubesats to provide continuous GPS radio occultation measurements over the South East Asian region. These measurements combined with measurements from ground based GPS receivers can provide a 3D reconstruction of the ionosphere in common volume measurement zones. The student will work to develop algorithms for radio occultation measurement retrievals and TEC calculation, identifying common volume measurements and adaptive imaging techniques using sparse measurements to derive optimal 3D plasma images with high temporal resolution. In addition the student will also serve as student project manager for building the first prototype cubesat carrying the GPS receiver for radio occultation measurements. The student is expected to gain an insight into the various subsystems of a spacecraft and defining the system level requirements for the mission. The student will have responsibility for maintaining schedule and leading the engineering group on periodic reviews and assessments.

Contact Person: Amal Chandran, email: [email protected]