Dear all,
The next Geophysics & Planetary (GP) Seminar will be given by our very own Dr. Bing Cao, a research scientist in IGPP. Bing will discuss the use of GNSS airborne radio occultation to probe atmospheric properties.
The seminar will be held in the Munk Conference Room on Wednesday, November 19th, at 3:00 PM. Coffee, snacks, and tea will be provided before and after the seminar. This seminar will be in-person only.
We look forward to seeing you at the seminar!
Title:
From Navigation Errors to Atmospheric Insights: Exploring the Atmosphere with GNSS Airborne Radio Occultation
Abstract:
Global Navigation Satellite System (GNSS) signals, originally designed for navigation and timing, are refracted and delayed as their ray paths traverse the atmosphere. These effects, once excluded as errors, provide valuable information about atmospheric properties. The GNSS radio occultation (RO) technique measures signal bending and delay to retrieve high-vertical-resolution, all-weather, bias-free profiles of refractivity, temperature, and moisture, and has been successfully implemented on multiple satellite missions. Airborne radio occultation (ARO) extends this capability to high-altitude research aircraft and stratospheric balloons, enabling flexible, regionally targeted observations for field programs such as atmospheric river and hurricane reconnaissance.
In this presentation, I will first outline how GNSS can be turned into an atmospheric profiler by exploiting sophisticated GNSS precise point positioning (PPP) tools. I will then describe how ARO observations are implemented in practice, from instrumentation development and processing algorithms through flight operations, to the delivery of near-real-time and post-processed products, and the current/future status of deployment. In the second part, I will focus on tropical atmospheric wave dynamics, using RO datasets from free-floating balloons to characterize tropical gravity waves and derive their intrinsic properties. I will show how these observations can be used to quantify wave impacts on the circulation and to explore how gravity waves modulate water vapor in the tropical atmosphere.
Best,
Baoning and Harrison
GP Seminar Committee