The relationship between organic aerosols and meteorological variables at the border between São Paulo Metropolitan Region and Atlantic Forest

• Grant number: 23/18250-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2024
• End date: February 28, 2026
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Meteorology
• Principal Investigator: Theotonio Mendes Pauliquevis Júnior
• Grantee: Raísa Batista Sanchez
• Host Institution: Instituto de Ciências Ambientais, Químicas e Farmacêuticas (ICAQF). Universidade Federal de São Paulo (UNIFESP). Campus Diadema. Diadema , SP, Brazil

Abstract

Within the period from December 2016 to March 2017, an intensive campaign of atmospheric gases and aerosol measurements was conducted in the city of Diadema, located at the boundary between the urban area of the Metropolitan Region of São Paulo (MRSP) and the Atlantic Forest domain. The experimental site is subject to the influence of moist air masses (due to sea breeze) before their mixing with anthropogenic emissions from the MRSP, and it may also receive occasional contributions from emissions originated in the Baixada Santista region. Instrumentation for trace gases (O3, NO2, SO2, CO, CO2) and aerosols was deployed, including a high-temporal-resolution mass spectrometer (ACSM: NO3, SO4, NH4, Cl, and organics), as well as instrumentation for aerosol physical properties (size distribution: SMPS and OPS; optical properties: absorption (MAAP) and scattering (Nephelometer), and filters.In this undergraduate research plan, we propose that the student revisit these measurements, focusing on the relationship between organic aerosols and meteorological variables. Monteiro dos Santos et al. (2021), utilizing Positive Matrix Factorization (PMF), extracted four components of organic aerosols from the ACSM measurements in the same database: oxygenated organic aerosol (OOA), biomass burning organic aerosols (BBOA), and two organic aerosols resembling hydrocarbons (HOAI and HOAII). The student will compare surface meteorological variables (wind, humidity, temperature, precipitation) with the concentration of these classes of organic aerosols. Measurements of sulfate, nitrate, and ammonia, also obtained, complete the comprehensive set of data collected in this campaign.The diurnal cycle of different aerosol components will be characterized, and periods with contrasting meteorological conditions will be inter-compared. This endeavor aims to contribute to an improved understanding of the dynamic processes influencing aerosol concentrations in the MRSP while providing advanced training to the student, whose undergraduate background lies in Environmental Sciences with a strong interest in Atmospheric Pollution.