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Atmospheric aerosol refers to a group of solid or liquid particles suspended in the atmosphere that has an impact on the planet’s climate by altering the radiative balance. Its effects can be direct or indirect. Aerosols serve as the starting point for condensation and the development of droplets known as Cloud Condensation Nuclei (CCN). In addition to interacting with radiation and affecting the optical characteristics of clouds, CCNs can alter the formation of droplets and ice crystals, cloud cover, and precipitation. Aerosols in the lower troposphere either move up to the upper troposphere/lower stratosphere (UT/LS) or, in a process known as new particle creation, trace gases move up to the UT and create new particles by condensing gases in the free atmosphere. Thus, in this study we analyzed the presence South American Tropopause Aerosol Layer (SATAL), an aerosol layer in the upper troposphere/lower stratosphere (UT/LS) in South America, over the Amazon region to characterize this layer. For that, it was used Aerosol Extinction 532 nm (AE532) from MERRA-2, for the period January/2002 to December/2021 and aerosol measurements in the upper troposphere from High Altitude Long Range Aircraft (HALO) airplane. The HALO measurements were made during the GermanBrazilian campaign Chemistry of the Atmosphere: Field Experiment in Brazil (CAFE-Brazil) that took place over the Amazon region during December/2022 and January/2023. Our results from MERRA-2 clearly show the presence of the SATAL over South America, specifically over the Amazon Basin at around 11-14 km height, with seasonal behavior like the ATAL and NATAL (over Asia region and North America, respectively). The maximum AE532 values occurred between October and November, coincident with the starts of the wet season period over South America. SATAL is formed first in the eastern Amazon eastern Amazon Basin, then moves to the Southern Amazon, where it weakens in December-January and finally dissipates in February-March. Because SATAL’s biggest peak occurs between October and November, our preliminary findings imply that SATAL is generated by organic aerosols, most likely associated with the dry season. Once, the source of aerosols probably is in the lower troposphere, the updraft mass flux from the convective activity during the active phase of the South American Monsoon System (SAMS) make them go up. Particles in the UT/LS have been one of the largest aerosol reservoirs in the atmosphere, and they can act as CCN in remote regions.