Starting from August 6th in 2019, Sentinel-5P TROPOMI along-track high spatial resolution (~5.5km at nadir) has been implemented.For data before August 6th of 2019, please check S5P_L2__AER_AI_1 data collection.The Copernicus Sentinel-5 Precursor (Sentinel-5P or S5P) satellite mission is one of the European Space Agency's (ESA) new mission family - Sentinels, and it is a joint initiative between the Kingdom of the Netherlands and the ESA. The sole payload on Sentinel-5P is the TROPOspheric Monitoring Instrument (TROPOMI), which is a nadir-viewing 108 degree Field-of-View push-broom grating hyperspectral spectrometer, covering the wavelength of ultraviolet-visible (UV-VIS, 270nm to 495nm), near infrared (NIR, 675nm to 775nm), and shortwave infrared (SWIR, 2305nm-2385nm). Sentinel-5P is the first of the Atmospheric Composition Sentinels and is expected to provide measurements of ozone, NO2, SO2, CH4, CO, formaldehyde, aerosols and cloud at high spatial, temporal and spectral resolutions.The TROPOMI UV Aerosol Index has been calculated based on wavelength dependent changes in Rayleigh scattering in the UV spectral range where ozone absorption is weak. A residual value is calculated from measured top-of-atmosphere (TOA) reflectance and per-calculated theoretical reflectance for a Rayleigh scattering-only atmosphere given a wavelength pair. TROPOMI UVAI products use the classical wavelength pair of 340/380 nm, and the OMI chosen 354/388 nm pair for the long-term continuous AI record. Figure 1 shows TROPOMI UVAI of orbit# 4060.