Small-scale variability of stratospheric ozone during the SSW 2018/2019 observed at Ny-Ålesund, Svalbard

Abstract

Abstract. Middle atmospheric ozone, water vapour and zonal and meridional wind profiles have been measured with the two ground-based microwave radiometers GROMOS-C and MIAWARA-C. The instruments are located at the Arctic research base AWIPEV at Ny-Ålesund, Svalbard (79° N, 12° E) since September 2015. GROMOS-C measures ozone spectra in the four cardinal directions with an elevation angle of 22°. This means that the probed airmasses at an altitude of 3 hPa (37 km) have a horizontal distance of 92 km to Ny-Ålesund. We retrieve four separate ozone profiles along the lines of sight and calculate daily mean horizontal ozone gradients which allow us to investigate the small-scale spatial variability of ozone above Ny-Ålesund. In winter 2018/2019 a major sudden stratospheric warming (SSW) took place with the central date at 2 January. We present the ozone, water vapour and wind measurements of the winter 2018/2019 and discuss the signatures of the SSW in a global context. We further present the evolution of the ozone gradients at Ny-Ålesund and link it to the planetary wave activity. At 3 hPa we find a distinct seasonal variation of the ozone gradients. In October and March a strong polar vortex leads to ozone decreases towards the pole. In November the amplitudes of the planetary waves grow until they break in the end of December and an SSW takes place. From November until February the ozone gradients mostly point to higher latitudes and the magnitude is smaller than in October and March. We attribute this to the planetary wave activity of wave number 1 and 2 which enabled meridional transport. The MERRA-2 reanalysis and the SD-WACCM model are able to capture the small-scale ozone variability and its seasonal changes.

Infrastructure needs on latitudinal and longitudinal chains of co-located ground-based observations

“…Thus, roughly 107 imagers could combine to form a network that covers the entire contiguous US while using the central region of the FOV (120º) to control the circular distortion at the edges, as shown in Figure 4 (b) (not including Hawaii and Alaska), and the whole cost estimate is less than $2 million. d. Consider adding multiple next-generation instruments at the poles: Next-generation radiometers such as TEMPERA and TEMPERA-C could provide continuous and nearly weather-independent temperature soundings up to the MLT; the WIRA instrument observes stratospheric and mesospheric winds; and the next-generation ozone and water vapor observations assess the strength of the upwelling and downwelling within the polar vortex (e.g., Krochin et al, 2022a, Schranz et al, 2019. Furthermore, the new TEMPERA-C radiometer is going to measure changes in the mesospheric magnetic field leveraging the Zeeman effect (Krochin et al, 2022b).…”

Atmospheric tomography using the Nordic Meteor Radar Clusterand Chilean Observation Network De Meteor Radars: networkdetails and 3DVAR retrieval

“…Optimal estimation is a technique often applied for atmospheric remote sounding and is described in detail in Rodgers (2000). The optimal estimation technique has become a standard tool in radiometry to retrieve atmospheric quantities such as winds, temperatures or trace gas concentrations (Livesey et al, 2006;Schwartz et al, 2008;Hagen et al, 2018;Schranz et al, 2019;Navas-Guzmán et al, 2016).…”

Frequency-Agile FFT Spectrometer for Microwave Remote Sensing Applications

“…An instrument that observes multiple emission lines with a frequency switched double-side-band receiver has been shown to be valuable for simultaneous measurements of carbon monoxide and ozone [5]. In [6], the value of joint ozone and wind measurements was demonstrated at the arctic station in Ny-Ålesund, Svalbard, using the 110 GHz ozone emission line.…”