Articles | Volume 18, issue 6
Research article
26 Mar 2018
Research article |  | 26 Mar 2018

Diurnal variation in middle-atmospheric ozone observed by ground-based microwave radiometry at Ny-Ålesund over 1 year

Franziska Schranz, Susana Fernandez, Niklaus Kämpfer, and Mathias Palm

Abstract. We present an analysis of the diurnal ozone cycle from 1 year of continuous ozone measurements from two ground-based microwave radiometers in the Arctic. The instruments GROMOS-C and OZORAM are located at the AWIPEV research base at Ny-Ålesund, Svalbard (79° N, 12° E), and gathered a comprehensive time series of middle-atmospheric ozone profiles with a high time resolution. An intercomparison was performed with EOS MLS and ozone sonde measurements and simulations with SD-WACCM. The measured data sets were used to study the photochemically induced diurnal cycle of ozone in the stratosphere and mesosphere. Throughout the year the insolation in the Arctic changes drastically from polar night to polar day. Accordingly, the seasonal variations in the diurnal ozone cycle are large. In the stratosphere we found a diurnal cycle throughout the entire period of polar day with the largest amplitude in April. In the mesosphere a diurnal cycle was detected in spring and fall. SD-WACCM has been proven to capture the diurnal cycle well and was therefore used to analyse the chemical reaction rates of ozone production and loss at equinox and summer solstice. Furthermore GROMOS-C proved capable of measuring the tertiary ozone layer above Ny-Ålesund in winter.

Short summary
We present 1 year of ozone measurements form two ground-based microwave radiometers located at Ny-Ålesund, Svalbard. The ozone measurements cover an altitude range of 25–70 km altitude and have a high time resolution of 1–2 h. With these datasets and model data a comprehensive analysis of the ozone diurnal cycle in the Arctic is performed for the different insolation conditions throughout the year. In the stratosphere we find a diurnal cycle which persists over the whole polar day.
Final-revised paper