This project is to produce a new data set of gravity waves in the upper stratosphere based on Cloud Imaging and Particle Size (CIPS) measurements from the Aeronomy of Ice in the Mesosphere (AIM) satellite. The CIPS data set at ~50 km altitude will provide measurements of gravity waves observed in CIPS measurements of ozone albedo that complement the Atmospheric Infrared Sounder (AIRS) measurements from the Aqua satellite at ~35 km. The postdoctoral fellow will work with CIPS researchers to produce the data set of waves and then work with the AIRS research team to analyze the gravity waves and understand their geophysical significance. The work builds on an ozone retrieval algorithm for CIPS data that was recently developed by the principal investigator (PI) as part of his PhD work. This project will be carried out at Virginia Tech under the mentorship of Dr. Scott Bailey and at NWRA in Boulder, CO under the mentorship of Dr. M. Joan Alexander and with the participation also of Dr. Cora Randall at University of Colorado, who is the PI on the CIPS instrument.
The effort will result in a new dataset for gravity waves which covers a segment of the spectrum which isn't presently well constrained by observations. The dataset will be made publicly available so that it can be used by the community to help advance our understanding of gravity waves and their effects on global circulation. The fellowship is crucial to the development of a young researcher who has already shown significant potential through his strong contributions to the AIM mission. The research project coupled with a strong mentorship program as well as teaching and faculty development opportunities will yield a valuable, productive member of the aeronomy community.
The goal of this project was to develop the capability to measure Gravity Waves (GW) observed in the rayleigh scattered albedo images from the Cloud Imaging and Particle Size (CIPS) instrument on board the Aeronomy of Ice in the Mesosphere (AIM) satellite. GWs are traveling disturbances in the Earth's atmosphere which transport significant energy and momentum from the troposphere into the upper atmosphere. These waves have scale sizes that are too small to be resolved in most global climate models, but are of critical importance to the dynamical forcing of the atmosphere. The CIPS instrument observes GWs in the lower mesosphere and is uniquely sensitive to GWs with vertical wavelengths longer than ~15 km and horizontal wavelengths between 20 and 300 km. Existing measurements in the lower mesosphere are sensitive to a distinct set of waves with lower vertical and longer horizontal wavelengths. Together with these existing measurements, CIPS adds to a more complete observational coverage of the GW spectrum in this region. GWs alter the mean atmospheric winds by depositing the "momentum flux" that they carry. An important result of this project was the determination that the mean momentum flux of the spectrum of waves CIPS observes is, at least, on the same order as that already observed by other instruments. Not only does CIPS add to the spectral coverage of GWs, but the additional population of waves it observes are important to the dynamical forcing of the mesosphere.
