Overview of the measurement site
Geographic coordinates of the Peterhof site are as follows: 59.88°N, 29.83°E, 20m asl. FTIR systems together with other equipment for atmospheric monitoring are situated at the University campus, in a suburb of greater Saint-Petersburg (~35 km from the city center). Saint-Petersburg is the 4th largest city in Europe with the population of 5.1 million people. Hence, the possibility of anthropogenic pollution influence should be borne in mind during spectra processing and the following analysis of retrieval results (gases TCs and profiles). The cases of FTIR observations through polluted air could be identified using data of in situ gas analyzers (NOx, O3, CO, CH4 and CO2) which started continuous monitoring in 2013.
The climate of the Saint-Petersburg region is classified as humid continental (Dfb - Köppen climate classification) with moderately mild winters and moderately warm summers. The average air humidity is of 78%. Frequent changes of Polar and Arctic air masses lead to highly variable weather. The westerlies are the dominant winds for Saint-Petersburg. The Saint-Petersburg region suffers from cyclone activity for about 140 days in a year therefore the number of overcast days is relatively high for the Peterhof station (~165 days per year).
Average number of measurement days per year for the period of 2009-2014 is of 100.
FTIR system
FTIR–spectrometer Bruker IFS 125HR for the high resolution (up to 0.0019 см-1) atmospheric measurements of solar spectra in wide spectral range from IR to UV (5-50000 см-1). Spectrometer is equipped by self-designed solar tracking system.