Michaela Imelda Hegglin

Research Interests

My research interests are reflected in a range of projects I’m involved in, but can be summarized more generally as the impact of ozone depleting substances and climate change on atmospheric composition, feedback mechanisms between chemistry, radiation, and transport, and the influence of these changes on human health and the ecosystem.


Projects I am/was involved in…


(most recent projects are listed first)


SPARC Data Initiative


The goal of the SPARC Data Initiative is to compare climatologies of mainly long-lived trace gases from satellite observations, determine their quality and representativeness, and make them accessible to future chemistry-climate model validation activities. I’m

co-lead of this new SPARC activity together with Dr. Susann Tegtmeier (IFM-GEOMAR) since October 2009.




AC&C is a joint SPARC/IGAC activity coordinating research on Atmospheric Chemistry and Climate coupling. Since October 2009, I’m a new co-lead of the AC&C activity group II together with Dr. Celine Mari (CNRS) and Dr. Mary Barth (NCAR), which focuses on chemical and physical processes determining the chemical composition and dynamical structure of the upper troposphere and lower stratosphere using models and observations.


Twenty Questions & Answers About the Ozone Layer: 2010 Update


I see communicating scientific results and environmental issues to the broader public as an important task for scientists in current times. One such endeavour is the booklet ‘Twenty Questions & Answers About the Ozone Layer’, which explains in detail the science behind the ozone layer and its depletion by anthropogenic chlorinated chemicals. Together with Dr. David W. Fahey (NOAA) I’m a coordinating lead author of this document, which is an integral part of the WMO/UNEP scientific ozone assessment.




Observations in the upper troposphere and lower stratosphere are difficult to obtain, however, are strongly needed given the climate sensitivity of this region. PREMIER is a candidate mission for the European Space Agency’s Earth Explorer satellite program. I am involved in the PREMIER Mission Advisory Group, whose goal is to define the science usage of the data and measurement needs and capabilities.




I was working within the C-SPARC project for the last 5 years as a Postdoc and Research Associate on chemistry-climate model validation and chemistry-climate coupling. I am particularly interested in how climate change will affect transport within the upper troposphere and lower stratosphere, which feedback mechanisms will result from these changes, and how they affect tropospheric air pollution due to transport of stratospheric tracers into the troposphere and changes in UV radiation.




The latest round of SPARC’s chemistry-climate model validation activity CCMVal (CCMVal-2) included for the first time the evaluation of the upper troposphere and lower stratosphere in chemistry-climate models due to its large sensitivity to climate change. Together with Dr. Andrew Gettelman (NCAR) I was co-lead author of chapter 7, ‘The upper troposphere and lower stratosphere’, of the comprehensive SPARC CCMVal report, published in 2010.




SPURT is the German acronym for ‘Trace gas transport in the tropopause region’ and was a German aircraft project between 2001 and 2003, within which I completed my PhD thesis. This work included the setup and implementation of the NOy, NO, and O3 measurement system, and its operation during eight seasonally distributed campaigns, as well as the processing and interpretation of the data.










Research Interests