EOL Seminar: In situ observations of ozone using Electrochemical Concentration Cell ozone sondes

Tuesday, July 20, 2021 - 15:30 to 16:30
Virtual (Webcast link provided below)
Contact Name: 
Melissa Ward
Contact Email: 
Contact Phone: 

SPEAKER: Dr. Holger Vömel - In-Situ Sensing Facility, Earth Observing Laboratory

DATE: July 20, 2021

Time: 3:30 - 4:30 pm MST

WEBCAST: https://operations.ucar.edu/live-eol

QUESTIONS: Slido will be used to answer your questions during the seminar.



In situ observations of ozone from small instruments flying on meteorological balloons provide vertical profiles from the surface to the middle stratosphere. These instruments are important tools in monitoring the stratospheric ozone layer, ozone pollution in the troposphere, and transport processes between the troposphere and stratosphere. Furthermore, they provide essential reference observations in the validation of space borne observations of ozone. Surprisingly, in some cases, they are also able to detect volcanic emissions.

Worldwide, about 60 stations monitor the distribution of ozone using the Electrochemical Concentration Cell (ECC) Ozone Sonde. The Assessment of Standard Operating Procedures for Ozone Sondes (ASOPOS) group of scientists reviews the operations for these instruments under the umbrella of the WMO Global Atmospheric Watch to assure that all measurements provide observations of similar data quality.

Significant progress made by this group of experts aims to reduce the uncertainty of ECC ozone observations to between 5 to 10 % over the entire profile. In addition to an update of the standard operating procedures, the most important result of this group is the recognition that the time response of the ECC plays an important role in the processing of its measurements, in particular in regions of very low ozone and sharp vertical gradients.

In my talk, I will provide some background on using ECC ozone sondes, describe the efforts of the ASOPOS team, and describe the time response processing of ozone sondes. This method improves measurements in the upper troposphere and makes the ECCs good tool for observations of ozone within the boundary layer. I discuss the ozone concentration in the upper tropical troposphere within the Southern Hemisphere Additional OZone Sonde (SHADOZ) network of tropical stations, in particular at Costa Rica, which has a more than 15-year record. In addition, this station features a significant number of observations of volcanic emissions, which are observed by the regular ozone soundings.