35-years of aerosols-PBAPs research in Brazil: the need to think outside the Amazonian box

Whilst there is a consensus that aerosol particles and primary biological aerosol particles (PBAPs) play an important role in regulating the global climate, with aerosols-PBAPs research increasing lately in Brazil, information summarizing the available knowledge is limited. Here, we present a systematic review of research published during the last 35-years on aerosols-PBAPs in Brazil. A total of 212 studies encompassing 474 cases met the selection criteria. The Amazon rainforest was the most studied biome represented by 72% of cases, followed by the Atlantic Forest with 18%. Studies focusing on the Amazon rainforest mostly studied climate-related issues and aerosol physics, with less than 5% examining the biological identity of aerosols, whereas outside the Amazon rainforest this number reached 16%. In addition, more than half of the cases within Amazon (55%) were held at seven sampling sites only, but conclusions were mainly extrapolated to the entire biome. On the other hand, research beyond Amazon has mostly addressed temporal and biological characterization of PBAPs, and not only is it scattered, but also scarce. Regarding sampling effort, most cases (72%) have had less than 100 days of sampling, and 60% of them spanned less than half a year of study, confining research to one or two seasons at the most. Consequently, while research from different countries that conduce their studies within Brazil and scientific fields are focusing on the same area, inconsistences are slowing the progress of this research topic. We argue that scientists from different fields of research (e.g., biologists, physicists) and countries should work together to produce more detailed and complete assessments of aerosols-PBAPs in the country as a whole, particularly on regards to their biological identity, given their importance to global climate regulation.