The rapid economic growth and a lack of strict implementation of air quality regulations have led to unqualified effects on the health, the environment, and the climate. In recent years, there has been an urgent need for the increased characterization of aerosols in terms of optical, micro-physical, and radiative properties and their climatic impacts. In the present study, the aerosol-climate implications were evaluated by aerosol radiative forcing (ARF) at three environmentally specific sites, Malindi (3 degrees S, 40.2 degrees E, 12 m asl), Mbita (0.42 degrees S, 34.20 degrees E, 1125 m asl), and Nairobi (1.0 degrees S, 36.0 degrees E, 1650 m asl), located in Kenya. The aerosol optical properties such as aerosol optical depth (AOD(440)), single scattering albedo (SSA(440)), asymmetric parameter (ASY(440)), and & Aring;ngstr & ouml;m exponent (AE(440-870)) showed significant annual and seasonal heterogeneities. They noticed high (low) values during the local dry (wet) seasons, attributed to changes in anthropogenic activities, emission sources, and prevailing dynamics played by the meteorology. The study also utilized measured spectral aerosol optical properties and two radiative transfer models in the short-wave (SW) and long-wave (LW) regions with their respective spectral bands (0.2-4.0 mu m) and (4.0-100.0 mu m) during 2007-2018. The direct ARF simulated in the SW using the Santa Barbara DISORT Atmospheric Radiative Transfer Model (SBDART) and the Coupled Ocean and Atmospheric Radiative Transfer models (COART) depicted high correspondence, evidenced by relatively high (r > 0.64) correlations over the three sites. The ARF simulated by the two models in the SW and LW regions exhibited significant seasonal heterogeneity, with maximum (minimum) values observed during the local dry (wet) seasons. The results from the present study could form a basis for other climate change studies and increase the accuracy of the existing climate models to enhance climate forecasting over the East Africa region.

Under the COVID-19-induced lockdown, there was a sharp decrease in pollution emissions, which led to previously unheard-of trends in India’s most dangerous pollutants. The study is considered for March-June 2020 to investigate the impact of lockdown on the concentrations of air pollutants, at the four stations in Andhra Pradesh, India. The study period was divided into Before Lockdown (BLD), During Lockdown (Phase-I (P-I), Phase-II (P-II), Phase-III (P-III), Phase-IV (P-IV)) and After Lockdown (ALD). The air pollutant concentrations over four stations were retrieved using in-situ measurements under the Central Pollution Control Board (CPCB), India network. The percentage contribution of PM2.5 in PM10 was recorded as 60–70

The aerosol-cloud interactions importantly influence the energy and water cycle of Earth-atmosphere system. The uncertainty of climate models is partly due to the lack of large-scale observational constraints of interaction between aerosol and water cloud. Based on CATS lidar time-resolved observations over the global marine region during 2015-2017, this study investigates the vertical effect of aerosol on marine water clouds, and evaluates the covariate influence of meteorological factors combined with European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis meteorological data. The mutual roles between aerosols as cloud condensation nucleation (CCN) and meteorological variables (temperature and relative humidity) contribute to the non-linear relationship of interactions between aerosol and water clouds. The results provide effective constraints for the parameterizations of aerosol-cloud interactions in current climate models.

In the present study, we examined the spatial and temporal variations in aerosol optical depth (AOD) at 550 nm and its relationship with various cloud parameters derived from the Moderate resolution Imaging Spectroradiometer (MODIS) sensor onboard Terra satellite. The data have been analyzed for the period of 10-years between March 2003 and February 2013 over 12 major cities in China. The results revealed that high AOD noticed over low latitude regions influenced with high anthropogenic activities and the low AOD observed for the high altitude and mountainous areas, since AOD accounts for the slant path which reduces the aerosol emissions. In addition, the aerosol variations in the atmosphere are complicated by several factors in emissions (natural and anthropogenic) as well as stagnant synoptic meteorology. From the temporal studies, it is clear that the maximum AOD was found during summer followed by spring and autumn with a minimum AOD in winter season for all the regions of study in China. Furthermore, we studied the relationship between AOD versus water vapor (WV), cloud fraction (CF), cloud optical thickness (COT), cloud effective radius (CER), cloud top pressure (CTP), and cloud top temperature (CTT) for the selected regions in China. Additionally, regression analysis and one paired student's t-Test were applied to represent the probability of data significant at 95% confidence for the derived AOD values and cloud parameters in order to provide a better understanding of aerosol-cloud interaction.

The global climatology (spatial and temporal) of the total cloud fraction (precipitating cloud (rain cloud + snow cloud) + non-precipitating cloud) during 2007–2016 is investigated based on the observations derived from the CloudSat. It is revealed that the total cloud fraction occurs in the tropical belt ( ±15° latitude) over all seasons. Among them, the mean fraction of precipitation clouds is 12

Aerosol effects upon ice clouds remain the most considerable uncertainty of the global climate forcing uncertainties. Dust aerosol and ice cloud properties over Tarim Basin (TB), China, from 2007 to 2021 are analyzed based on the simultaneously retrieved multiple satellite observations. The present study examines the variations and potential interaction mechanisms among different ice clouds and aerosol parameters such as ice water content (IWC), ice water path (IWP), aerosol extinction coefficient (EC), and aerosol optical depth (AOD). The results showed a strong agreement between IWC and EC with the steeper vertical variation and the maximum median in summer. The interannual variability of IWC, IWP, and AOD bear reasonable natural climate variability with steady changes and showed a significant seasonal cycle with IWC and IWP. Whereas the AOD median depicted maximum in the summer or spring season. Also, the correlation studies are presented utilizing the satellite data where the correlation coefficient is a maximum of 0.65 for AOD-OMI (Ozone Monitoring Instrument) with IWP-MLS (Microwave Limb Sounder), suggest AOD has a positive effect on the formation of ice clouds. Above results of ice cloud and dust aerosol variations, which could be partially attributed to the Taklamakan Desert dominate the dust aerosols in TB, which occurred roughly during the same seasons. This is affected by weather conditions and primarily drives the seasonal and annual cycle behavior of ice cloud and dust aerosol over the region. Multi-source satellite detection can capture the main characteristic changes of ice clouds and dust aerosol and provide adequate observational facts in this study. Therefore, the present study may provide valuable complementary or alternative information for ice clouds, dust aerosol, and their interaction research in the troposphere or upper troposphere. It may also offer more consistent input for climate research on the TB area in China.

Measurements on size distribution of atmospheric aerosol were made at Anantapur, during January to December 2005. A ten channel Quartz Crystal Microbalance Cascade Impactor (QCM) is used to study the response of aerosol characteristics to mesoscale and synoptic processes. The accumulation mode aerosol mass concentration (submicron Ma ≈ 0.4 to 0.05 μm) is found to be minimum (~10 μg/m3) and maximum (~27 μg/m3) during the months March–August and November–December, 2005 respectively. Coarse mode aerosol mass concentration (supermicron Mc ≈ 12.5 to 0.8 μm) is found to be maximum (~17 μg/m3) during the months of July and September 2005. The effect of wind on the concentration of Mc and Ma has been studied. The variation in the effective radius (Reff) from 0.1 μm to 0.4 μm indicates how the size of the particles varied seasonally. The present study brings out the fact that the size distributions on aerosols are very much affected by the meteorological parameters.

This article presents variations of simultaneous measurements of near surface ozone (O3) at two sites namely Anantapur [14.62°N, 77.65°E], a semi arid rural location in India and Xi'An [34.20°N, 108.98°E], a semi arid urban location in China during January-July 2009. The results showed a clear diurnal cycle of O3 with a minimum at sunrise and a maximum at noon for both the sites. The monthly average diurnal variation shows that the maximum/minimum ozone was observed in March/July whereas in Xi'An maximum/minimum ozone was observed in July/February because of different climatic zones and rainfall activity. The average diurnal variation of O3 for different seasons (summer and winter) shows higher ozone concentration at Anantapur than at Xi'An. This may be due to slower titration of NO in the evening hours at Anantapur. But in Xi'An, the highest ozone levels recorded in noon hours for some days in June and July months. This is mainly due to strong emissions of NOx, VOC and high solar radiation and this implies significant negative effects on vegetation and regional air quality around Xi'An. The rate of increase of ozone is almost the same at two sites but the rate of decrease of ozone is more at Xi'An than at Anantapur which is due to the higher NOx concentration from vehicular emission and also due to the fast titration of O3. The maximum 54% of frequency distribution of ozone lies between 20–45 ppbv at Anantapur whereas in Xi'An 34% lies in the range of 0–5 ppbv, 32% of Ozone lie between 5–20 ppbv and 24% of all O3 lie in the range of 20–45 ppbv.

Surface measurements of O3, NO, NO2 and NOx have been made over a semi-arid rural site, Anantapur (14.62°N; 77.65°E; 331 m asl) in southern India, during January-December 2010. The highest monthly mean O3 concentration was observed in April (56.1 ± 9.9 ppbv) and the lowest in August (28.5 ± 7.4), with an annual mean of 40.7 ± 8.7 ppbv for the observation period. Seasonal variations in O3 concentrations were the highest during the summer (70.2 ± 6.9 ppbv), and lowest during the monsoon season (20.0 ± 4.7 ppbv), with an annual mean of 40.7 ± 8.7 ppbv. In contrast, higher NOx values appeared in the winter (12.8 ± 0.8 ppbv) followed by the summer season (10.9 ± 0.7 ppbv), while lower values appeared in the monsoon season (3.7 ± 0.5 ppbv). The results for O3, NO and NO2 indicate that the level of oxidant concentration ([OX] = NO2 + O3) at a given location is the sum of NOx-independent ”regional contribution” (background level of O3) and linearly NOx-dependent ”local contribution”. The O3 concentration shows a significant positive correlation with temperature, and a negative correlation with both wind speed and relative humidity. In contrast, NOx have a significant positive correlation with humidity and wind speed, and negative correlation with temperature. The slope between [BC] and [O3] suggests that every 1 μg/m^3 increase in black carbon aerosol mass concentration causes a reduction of 4.7 μg/m^3 in the surface ozone concentration. A comparative study using satellite data shows that annual mean values of tropospheric ozone contributes 12% of total ozone, while near surface ozone contributes 82% of tropospheric ozone. The monthly mean variation of tropospheric ozone is similar to that tropospheric NO2, with a correlation coefficient of +0.80.

China is considered one of the nitrogen deposition hotspots in the world. Measurements to date have focused mainly on inorganic nitrogen, organic nitrogen and the size distribution of particulate nitrogen has yet to be studied. Lack of dry deposition observations imposes a reliance on models, resulting in a much larger uncertainty relative to wet deposition which is routinely measured. In this study, dry and wet organic and inorganic nitrogen deposition were comprehensively measured in Nanjing in 2019, and nitrogen species in size-segregated particles were investigated. Total annual nitrogen deposition flux was up to 29.96 kg N ha(-1) yr(-1) in Nanjing, with wet deposition contributed slightly more (51.90%) to total deposition than dry deposition (48.10%). Observations revealed that reduced nitrogen (NHx = NH3 + NH4+) contributed 65.49% of the total inorganic nitrogen deposition budget, which implied that the control of reduced N in urban environments is needed to improve local air quality. Dry deposition of ammonia played an especially key role in dry deposition, contributing from 18.17% to 55.91% in different seasons. The deposition flux of water-soluble organic nitrogen (WSON) dominated by wet deposition, with the wet WSON about 4.6 times higher than that of dry deposition and contributed 41.18% of the wet nitrogen deposition. The wet N deposition in summer was significantly higher than in the other three seasons. The seasonal patterns in dry deposition were driven mostly by seasonal concentration patterns. The highest deposition of ammonia occurred in summer, while the deposition of nitrogen dioxide, particulate ammonium and nitrate peaked in winter. The maximum dry and wet WSON deposition appeared in autumn. Higher NH4+ concentration almost distributed in each size bin and centered in ranges of 0.18-1.0 mu m, while higher NO3- concentration scattered in particle size ranges of 1.8-5.6 mu m and 0.18-1.0 mu m.

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The present work extensively demonstrates spatiotemporal climatological changes and trends, and a forecast modeling approach by utilizing the Machine Learning tools observed in aerosol optical depth (AOD) over Andhra Pradesh (AP) State in South India. In this study, the AOD at 550 nm (AOD550) and Ångström Exponent (AE470-870) data were retrieved from Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2) reanalysis data from 1981 to 2020 and compared with MODIS for the collocated 2 period. MERRA-2 annual AOD550 showed a high (0.16) in the North AP region and gradually decreased in the South AP (< 0.11) with moderate in the Central AP exhibiting a south-to-north gradient. Seasonally, the spatial distribution of AOD550 was observed high in the pre-monsoon (or summer) and monsoon seasons over the North and Central AP areas attributed to increased natural and anthropogenic aerosols. Whereas low AOD550 was observed in all seasons over South AP. The study area experiences high AOD in pre-monsoon due to the massive influx of dust particles from the Arabian Deserts to the inland during the transition from pre-monsoon to monsoon season. The Mann-Kendal trend analysis indicates a significant (99

The present study analyzes simultaneous and collocated measurements of spectral columnar aerosol optical depth (AOD) and the variations in total mass concentration of near surface aerosols in the marine atmosphere over the Bay of Bengal (BoB) during the winter phase of the Integrated Campaign for Aerosols, gases and Radiation Budget (W-ICARB) expedition of December and January 2008/2009 on board the Oceanographic Research Vessel (ORV) of Sagar Kanya. High AOD500 values (> 0.8) are found close to coastal regions in the western and northern BoB due to outflow of aerosols and pollutants from the densely populated Indo-Gangetic Plain (IGP). In these regions, the Ångström exponent α380–1020 values are also found to be high (~1.2–1.3), indicating relative abundance of accumulation-mode continental aerosols. Low AOD500 (0.1–0.2) values are observed in central and southern BoB, far away from the mainland. The AOD500 and total aerosol mass loading increased along with the latitude. The total mass concentration is found to vary between 15 μg/m3 and 45 μg/m3, with higher loadings near the east coast and northern parts of the BoB. NCEP reanalysis of the data with winds at 925 hPa, along with airmass trajectories calculated using the HYSPLIT model, suggest transport of continental aerosols from central and northern India over the BoB at lower heights, and mineral dust aerosol transport from arid regions in the west of India at higher altitudes; while the increase in aerosol loading over eastern BoB was strongly affected by airmasses originating from Southeast Asia. The spatial correlation map between the MODIS and MISR AOD data is analyzed, revealing a strong correlation between the two datasets. The influence of wind speed and continental airmass on AOD is also examined, which provides information on the effects of the adjoining landmass on the marine aerosol field.

This paper reports the observational results of aerosol optical characteristics, modification processes and discrimination of key aerosol types over Skukuza (24.9°S, 31.5°E, and 150 m), a subtropical rural site in South Africa (SA), using CIMEL Sunphotometer data, part of the AErosol RObotic NETwork (AERONET), from December 2005 to November 2006. The results show that a pronounced spectral and temporal variability in the optical properties of aerosols is mainly due to anthropogenic emissions. The discrimination of different aerosol types over Skukuza is also made using the daily mean values of aerosol optical depth at 500 nm (AOD500) and Ångström exponent (α440–870) by applying the threshold values. The results of the analysis indentified three individual components (biomass burning/urban (BU), desert dust (DD) and clean maritime (CM) aerosol types) of differing origin, composition and optical characteristics, and revealed that the percentage contribution of each of type of aerosol changed significantly from season to season. We also derived the curvature of a2 in an attempt to obtain information on aerosol-particle size and type, although the results revealed that the curvature alone is not enough to achieve this. In addition,, we analyzed the seasonal changes in aerosol characteristics using the classification scheme introduced in Gobbi et al. (2007) based on the measured scattering properties (α, dα) derived from the Sunphotometer data. The results show that during spring an extremely large fraction of fine-mode aerosols (η > 70

A comprehensive and robust dataset of tropospheric aerosol properties is important for understanding the effects of aerosol–radiation feedback on the climate system and reducing the uncertainties of climate models. The “Third Pole” of Earth (Tibetan Plateau, TP) is highly challenging for obtaining long-term in situ aerosol data due to its harsh environmental conditions. Here, we provide the more reliable new vertical aerosol index (AI) parameter from the spaceborne-based lidar CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) on board CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) for daytime and nighttime to investigate the aerosol's climatology over the TP region during 2007–2020. The calculated vertical AI was derived from the aerosol extinction coefficient (EC), which was rigorously quality-checked and validated for passive satellite sensors (MODIS) and ground-based lidar measurements. Generally, our results demonstrated that there was agreement of the AI dataset with the CALIOP and ground-based lidar. In addition, the results showed that, after removing the low-reliability aerosol target signal, the optimized data can obtain the aerosol characteristics with higher reliability. The data also reveal the patterns and concentrations of high-altitude vertical structure characteristics of the tropospheric aerosol over the TP. They will also help to update and make up the observational aerosol data in the TP. We encourage climate modelling groups to consider new analyses of the AI vertical patterns, comparing the more accurate datasets, with the potential to increase our understanding of the aerosol–cloud interaction (ACI) and aerosol–radiation interaction (ARI) and their climate effects. Data described in this work are available at https://doi.org/10.11888/Atmos.tpdc.300614 (Huang, 2023).

Ozone (O3) pollution with excessive near-surface O3 levels has been an important environmental issue in China, although the anthropogenic emission reductions (AER) have improved air quality since 2013. In this study, we investigated the sensitivities of atmospheric chemical environment with the urban and rural changes to the AER targeting a typical O3 pollution episode over North China in summer 2019, by conducting two WRF-Chem simulation experiments under two scenarios of anthropogenic emission inventories of years 2012 and 2019 with the meteorological conditions in the 2019 summertime O3 pollution episode for excluding the meteorological impacts on O3 pollution. The results show that the unbalanced AER aroused more serious O3 pollution in urban and rural areas. The intense NO reduction was responsible for the significant increments of urban O3, while the falling NO2 and NO synergistically devoted to the slight O3 variations in rural areas. Induced by the recent-year AER, the urban O3 production was governed by VOCs-limited and transition regime, whereas the NOx-limited regime dominated over rural areas in North China. Also, the AER reinforced the atmospheric oxidation capacity with the elevations of atmospheric oxidants O3 and ROx radicals, strengthening the chemical conversions to secondary inorganic particles. In both urban and rural areas, the sharp drop in SO2 caused a decrease in sulfate fraction, while the enhanced AOC accelerated the transformation to nitrate even when NOx was reduced. The AER induced nitrate to occupy the principal position in secondary PM2.5 in urban and rural areas. The AER promoted daytime and suppressed nighttime the nitrate production in urban areas, and more vigorous conversion of secondary aerosols were found in rural areas with much lower AOC increments. This study provides insights from a case study over North China in distinct responses of urban and rural O3 pollution with secondary particle changes to AER in urban and rural atmospheric environment changes, with implications for an effective abatement strategy on O3 pollution.

The present study examines the spatiotemporal changes in aerosol optical depth (AOD) and five aerosol species over the Middle East and North Africa (MENA) regions and incorporates an advanced Machine Learning model to predict AOD. The study utilizes reanalysis data from the Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), and the Copernicus Atmosphere Monitoring Service Reanalysis (CAMSRA), in conjunction with the MODIS spanning from 2003 to 2020. Seasonal-averaged AOD550 showed the dominance of aerosols in the summer and spring seasons, primarily driven by dust and black carbon, with dust being the most significant contributor due to frequent storms and desert conditions. Other contributors such as sea salt, sulfate, and organic carbon also play crucial roles, underscoring the complex interplay between natural and anthropogenic aerosols. The validation results revealed a high coefficient of determination (R²) for AOD ranging from 0.76 to 0.96 across these datasets. This demonstrates strong predictive accuracy with the XGBoost model, which shows a robust correlation between predicted and actual AOD values with minimal error and no significant bias. The AI/ML model analysis further elucidates the contributions of individual aerosol species to AOD predictions, revealing that dust and black carbon consistently enhance AOD. This study reveals that AOD fluctuations in the MENA region are driven by meteorological factors and drought-induced dust emissions. Ultimately, long-term reliable atmospheric composition reanalysis data can supplement ground-based or remote sensing observations in air quality research, emphasizing the need for continuous assessment of aerosols to inform policies aimed at reducing air pollution and mitigating climate change impacts.

The present study explores the intricacies of CALIPSO Level 3 optimized Aerosol Optical Depth (AOD) and Dust Aerosol Optical Depth (DAOD) products. Hence, the study focused on regions in the Middle East and North Africa (MENA) across different seasons from January 2007 to December 2020. The study utilizes a refined 1 degrees degrees x 1 degrees degrees grid resolution to analyze horizontal distribution patterns, seasonal variations, and the interplay of various aerosol constituents. The Middle East (ME) stands out with intensified AOD during transitional periods, and the Saharan- Sahel Dust (SSD) belt exhibits higher DAOD during specific seasons. Regions with significant industrialization and human activities exhibit high non-dust AOD values, while major dust sources like the SSD and the Arabian Desert showed high DAOD values in the spring and summer seasons. The study reveals seasonal variations in AOD and DAOD, with different regions showing distinct characteristics influenced by topographic and environmental factors. Observational evidence on the vertical distribution of dust layers is crucial for modeling studies to assess the impact of airborne dust particles on radiation and clouds. However, there are challenges in assimilating dust into atmospheric models due to limited ground measurements near dust sources. Further, the statistical metrics highlight regional and seasonal variations in DAOD, Dust Center of Mass, and Dust Top Height. The analysis extends to particle depolarization ratio, aerosol classification, spatial deviation in dust composition, AOD, and cloud properties (e.g., cloud optical thickness and cloud fraction). This has been influenced by several factors such as atmospheric circulation patterns, temperature, humidity, and land cover changes. Trends in AOD and DAOD over timescale indicate regional variations in aerosol concentrations. The study offers valuable insights into the complex atmospheric phenomena shaping the examined regions over the 13 years.

In this study, we have used the Terra satellite onboard of the Moderate Resolution Imaging Spectroradiometer (MODIS) to investigate the spatial and temporal relationship between aerosol optical depth (AOD) and cloud parameters namely, water vapor (WV), cloud optical depth (COD), cloud fraction (CF), cloud effective radius (CER), cloud top pressure (CTP), and cloud top temperature (CTT) based on 10 years (from January 2004 to December 2013) of dataset over six locations in South Africa (SA). The obtained results indicated seasonal variation in AOD, with high values during spring (September to November) and low values in winter (June to August) in all locations of study. In terms of temporal variation, AOD was lowest at Bloemfontein 0.06 ± 0.04 followed by Cape Town 0.08 ± 0.02, then Potchefstroom 0.09 ± 0.05, Pretoria and Skukuza had 0.11 ± 0.05 each and with the highest at Durban 0.13 ± 0.05. The mean Angstrom exponent (AE) values for each location showed a general prevalence of fine-mode particles which dominates the AOD for most parts of the year. A hybrid single particle Lagrangian integrated trajectory (HYSPLIT) model was used for trajectory analysis in order to determine the origin of airmasses and to understand the variability of AOD. We then studied the relationship between AOD, cloud parameters and precipitation over selected locations of SA so as to provide a better understanding of aerosol-cloud-precipitation interactions. All these correlations examined over six sites were observed to be depended on the large-scale meteorological variations.

Understanding the driving factors for the change of climatic patterns is crucial for the implementation of mitigation and adaptation measures. Significant effort has been made to understand changes in climatic patterns; however, less has been done to investigate the driving factors that influence the trends of early rainfall over Malawi. Hence, a substantial research gap exists concerning in the implementation of mitigation and adaptation measures. The present study investigates the implications of atmospheric aerosols on precipitation during the early rainfall season over Malawi. Open burning, such as bushfires and burning of crop residues by local farmers, are the major anthropogenic activities enhancing aerosol accumulation in the atmosphere and hence need to be strictly controlled over the domain and the surrounding region. The present results show that rainfall generally starts between October and November and gradually increases with the maximum observed in January and ends in March in most areas. Monthly aerosol optical depth (AOD 550 ) has an opposite pattern to that of rainfall with high AOD 550 (>0.4) between September and October, mostly over southern areas and along with Lake Malawi. An analysis of rainfall during the beginning of the season indicates a significant decrease of rainfall over the southern areas of Malawi, associated with high AOD 550 , while insignificant change is observed over the central and northern areas associated with low AOD 550 values. Statistical analyses among AOD 550 , cloud effective radius (CER), and precipitation demonstrates that negative trends of rainfall are strongly associated with a high concentration of anthropogenic aerosols from biomass burning during October. These aerosols might have absorbed excess moisture and disrupted local convective processes associated with the first rainfall that the domain receives, between the months of October and November. Therefore, regional control measures are required to reduce the excess emissions of anthropogenic aerosols into the atmosphere, such as controlling open burning during the active fire period (July-October).