Decadal time series of high-resolution downwelling spectral radiancemeasurements from Concordia Station, Antarctica

In December, 2011 the REFIR-PAD Fourier transform spectroradiometer was installed in Concordia Station, Antarctica to perform continuous monitoring of the atmospheric downwelling emitted radiance in the middle-far infrared region. The spectroradiometer is supported by several auxiliary instruments to monitor ground and sky conditions and, since 2020, by a compact lidar sensor to provide cloud structure in the lower troposphere and boundary layer region, thus establishing a complete and integrated set of sensors for the monitoring of the Antarctic troposphere.

The main product in the data set provided by the observing system consists in high-resolution spectral radiances measured in the 100-1500 cm-1 region with a 0.4 cm^-1 resolution. This allows us not only to separate the contributions to the radiation budget due to H₂O, CO₂, O₃ and clouds, but also to retrieve vertical profiles of water vapor and temperature, columnar amounts of minor constituents and cloud properties through a data inversion process.

The production of a consistent long-term dataset needs to front multiple challenges which are intrinsic in long period continuous operation in extreme environment, methods for the correction of systematic effects and to perform automatic data quality assessment had been developed in order to be able to make the data available for use by the atmospheric science community.

An example of the results that can be obtained exploiting the advantage of long term measurement and high temporal resolution provided by the dataset is the identification and analysis of extreme events: not only it is possible to perform a detailed analysis of the most prominent events on an hourly timescale, but also it is possible to search the dataset for the occurrence and statistics of minor events that could be of similar origin.