Advection of Biomass Burning Aerosols towards the Southern Hemispheric Mid-Latitude Station of Punta Arenas as Observed with Multiwavelength Polarization Raman Lidar

Classification of atmospheric aerosols and clouds by use of dual-polarization lidar measurements

Accurate identification of aerosols and cloud from remote sensing observations is of importance for quantitatively evaluating their radiative forcing and related impacts. Even though polarization lidar has exhibited a unique advantage of classifying atmospheric aerosols and clouds over the past several decades, polarization measurements are often achieved at one wavelength (UV or VIS) using laser remote sensing. To better identify the types of aerosols and clouds, we developed a ground-based dual-polarization lidar system that can simultaneously detect polarization measurements at wavelengths of 355 nm and 532 nm. Our results show that the volume depolarization ratios (VDRs) at 355 nm and 532 nm markedly differ for typical types of aerosols and clouds in the atmosphere. For non-spherical particles, the ratio of VDRs at 532 nm and 355 nm are 2.87 ± 1.35 for ice cloud and 1.51 ± 0.29 for dust-dominated aerosols, respectively. However, for spherical particles, the ratios are 0.43 ± 0.26 for water cloud and 0.56 ± 0.05 for air pollutants. Consequently, we proposed a simple reliable method for classifying atmospheric aerosols and clouds from polarization measurements observed by the developed lidar system. The proposed method first distinguishes clouds from aerosols using a combination of the color ratio (CR, 532 nm/355 nm) and attenuated backscattering coefficients (ABC) at 532 nm. Then, subtypes of clouds and aerosols are identified based on the ratio of VDRs at 532 nm and 355 nm. The results showed that dual-polarization lidar measurements can remarkably improve the classification of atmospheric aerosols and clouds, compared with results using a traditional method. This study illustrates that more information on atmospheric aerosols and clouds can be obtained from polarization measurements at multiple wavelengths by active remote sensing.

Impact of exposure to smoke from biomass burning in the Amazon rain forest on human health

This review study aimed to determine the relationship between exposure to smoke from biomass burning in the Amazon rain forest and its implications on human health in that region in Brazil. A nonsystematic review was carried out by searching PubMed, Google Scholar, SciELO, and EMBASE databases for articles published between 2005 and 2021, either in Portuguese or in English, using the search terms "biomass burning" OR "Amazon" OR "burned" AND "human health." The review showed that the negative health effects of exposure to smoke from biomass burning in the Amazon have been poorly studied in that region. There is an urgent need to identify effective public health interventions that can help improve the behavior of vulnerable populations exposed to smoke from biomass burning, reducing morbidity and mortality related to that exposure.