Hannah Kessenich busts ozone hole myths
For World Ozone Day, the University of Otago asked Hannah what people misunderstand about the ozone hole. The short answer: almost everything.
Ozone in the Antarctic stratosphere shapes the jet streams that steer weather across Australasia. This, in turn, affects global climate forecasting. We are quantifying how much forecasting ability will be lost when the Aura record ends. With this information we will set hard targets on what a replacement instrument must deliver.
The work has four strands: establishing the link between ozone data quality and extreme-event forecasting, defining instrumental requirements for the photonics and engineering teams, retrieving atmospheric information from the instrument using the ARTS radiative transfer model, and identifying which further gases the same technique could measure.

Advisor — Stratospheric Ozone
Bodeker Scientific
Greg Bodeker is the director of Bodeker Scientific Ltd, an independent research organisation that has been operating in New Zealand since October 2009. Bodeker Scientific conducts fundamental climate change research as well as research at the interfaces of climate and other disciplines (e.g. climate and finance, and climate and architecture). Greg has a PhD in Physics from the University of Natal in South Africa, and worked for the National Institute of Water and Atmospheric Research (NIWA) for a little over 15 years where he developed a strong programme of research in atmospheric chemistry and physics with a focus on Antarctic ozone depletion. Greg is also an adjunct professor at Victoria University. He has a passion for seeing innovation used to transition New Zealand's economy to a long-term sustainable model.
Advisor — Aura MLS Principal Investigator
NASA Jet Propulsion Laboratory, California, USA

Advisor — Earth Observation & End Users
Finnish Meteorological Institute, Finland
Johanna Tamminen received a PhD in applied mathematics from the University of Helsinki in 2004 and in 2026 she was conferred as honorary doctorate in technology at the LUT University, Finland. She has strong expertise in research coordination and over 30 years of experience in atmospheric remote sensing and mathematical and statistical methods to analyse and characterize satellite data and related uncertainties. Currently she is a Research Professor at the Finnish Meteorological Institute (FMI) and leading the Earth Observation Research Unit of FMI’s Space and Earth Observation Centre. She has published over 130 peer-reviewed articles. During the years, her scientific interests have widened from remote sensing of ozone to air quality, greenhouse gases, emissions and more generally to climate. She is and has been member of various panels related to satellite remote sensing, European Space Sciences Committee (2024-2027), ESA Advisory Committee on Earth Observation (2018-2022), GCOS /WRCS Atmospheric Observation Panel for Climate (2018 – 2022), and Swedish National Space Agency (SNSA). She is Co-Principal Investigator of Ozone Monitoring Instrument on-board EOS-Aura satellite, Chair of EUMETSAT Atmospheric Composition Satellite Application Facility (AC-SAF) Steering Group, and previous member of ESA Mission Advisory Group on Sentinel 5 Precursor mission (2012-2018) and Anthropogenic CO2 Monitoring Mission (2017-2019). She acted as the vice director of Research council of Finland funded Centre of Excellence in Inverse Modelling and Imaging (2018 – 2025) and co-PI of Flagship on Advanced Mathematics for Sensing, Imaging and Modeling (FAME) since 2023.
For World Ozone Day, the University of Otago asked Hannah what people misunderstand about the ozone hole. The short answer: almost everything.
A two-year Catalyst: Seeding project pairs Tuwhiri's photonic sensor with a flight-proven JPL microwave spectrometer, aimed at measuring stratospheric water vapour.
Florian Sedlmeir and Hannah Kessenich presented the programme's photonics and atmospheric science work to around 20,000 geoscientists.