scholarly journals Regional flow climatology for central Mexico (Queretaro): a first case study

2021 ◽  
Author(s):  
Daniel Rozanes-Valenzuela ◽  
Adolfo Vicente Magaldi ◽  
Dara Salcedo
Keyword(s):  
Flow Regimes ◽  
Industrial Area ◽  
Central Mexico ◽  
Wind Fields ◽  
Hysplit Model ◽  
Back Trajectories ◽  
Criteria Pollutants ◽  
Regional Flow ◽  
First Case ◽  
Regional Sources

A flow climatology was established for the Metropolitan Area of Queretaro (MAQ), in central Mexico, by analyzing four years (2014-2017) of back-trajectories generated using the HYSPLIT Model. Two flow regimes were found: one from June until September (rainy regime); the other from December to May (dry regime). October and November were considered transition months. Northeasterly flows were present throughout the year; in contrast, trajectories from the southwest were much less frequent and observed mainly during the dry regime. An analysis of the wind fields from the NARR database for a longer period of time (1979 – 2019), suggests that these results are representative of the average conditions of the atmosphere at the study site. Some of the northeasterly trajectories observed originate within a desertic region of the state of Queretaro, where several limestone mines are located. During the dry regime and transition months some clusters originate at the industrial area in Guanajuato, which includes the Salamanca refinery. As air transport of pollutants follow these paths, this analysis could be useful for identifying regional sources that affect the MAQ and possibly increase its air pollution load. In fact, the variability of criteria pollutants concentrations matched the flow regimes described above.

scholarly journals Identification of the Aerosol Types over Athens, Greece: The Influence of Air-Mass Transport

2010 ◽  
Vol 2010 ◽  
pp. 1-15 ◽  
Author(s):  
D. G. Kaskaoutis ◽  
P. G. Kosmopoulos ◽  
H. D. Kambezidis ◽  
P. T. Nastos
Keyword(s):  
Winter Season ◽  
Saharan Dust ◽  
Dust Particles ◽  
Hysplit Model ◽  
Air Mass ◽  
Back Trajectories ◽  
Air Masses ◽  
Local Pollution ◽  
Coarse Mode ◽  
Aerosol Types

Aerosol optical depth at 550 nm () and fine-mode (FM) fraction data from Terra-MODIS were obtained over the Greater Athens Area covering the period February 2000–December 2005. Based on both and FM values three main aerosol types have been discriminated corresponding to urban/industrial aerosols, clean maritime conditions, and coarse-mode, probably desert dust, particles. Five main sectors were identified for the classification of the air-mass trajectories, which were further used in the analysis of the ( and FM data for the three aerosol types). The HYSPLIT model was used to compute back trajectories at three altitudes to investigate the relation between -FM and wind sector depending on the altitude. The accumulation of local pollution is favored in spring and corresponds to air masses at lower altitudes originating from Eastern Europe and the Balkan. Clean maritime conditions are rare over Athens, limited in the winter season and associated with air masses from the Western or Northwestern sector. The coarse-mode particles origin seems to be more complicated proportionally to the season. Thus, in summer the Northern sector dominates, while in the other seasons, and especially in spring, the air masses belong to the Southern sector enriched with Saharan dust aerosols.

scholarly journals Aerosol Characteristics in the Three Poles of the Earth Observed by CALIPSO

2020 ◽  
Author(s):  
Yikun Yang ◽  
Chuanfeng Zhao ◽  
Quan Wang ◽  
Zhiyuan Cong ◽  
Xingchuan Yang ◽  
...  
Keyword(s):  
South Asia ◽  
Ross Sea ◽  
Temporal Trends ◽  
Arctic Region ◽  
The Arctic ◽  
Hysplit Model ◽  
Back Trajectories ◽  
Air Masses ◽  
Spatial And Seasonal Variation ◽  
The Antarctic

Abstract. To better understand the aerosol properties over the Arctic, Antarctic, and Tibetan Plateau (TP), the aerosol optical properties were investigated using 13 years CALIPSO L3 data, and the back trajectories for air masses were also simulated using the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model. The results show that the aerosol optical depth (AOD) has obvious spatial and seasonal variation characteristics, and the aerosol loading over Eurasia, Ross Sea, and South Asia is relatively large. The annual average AOD in the Arctic, Antarctic, and TP are 0.046, 0.025, and 0.098, respectively. The Arctic and Antarctic regions have larger AOD values in winter and spring, while the TP in spring and summer. There are no significant temporal trends of AOD anomalies in the three study regions. Clean marine and dust-related aerosols are the dominant types over ocean and land respectively in both the Arctic and Antarctic, while dust-related aerosol types have greater occurrence frequency (OF) over the TP. The OF of dust-related and elevated smoke is large for a broad range of heights, indicating that they are likely transported aerosols, while other types of aerosols mainly occurred at heights below 2 km in the Antarctic and Arctic. The maximum OF of dust-related aerosols mainly occurs at 6 km altitude over the TP. The analysis of back trajectories of the air masses shows large differences among different regions and seasons. The Arctic region is more vulnerable to mid-latitude pollutants than the Antarctic region, especially in winter and spring, while the air masses in the TP are mainly from the Iranian Plateau, Tarim Basin, and South Asia.

scholarly journals Chemical composition of rainwater collected from 2006 to 2009 in Mexico City and at a rural site at Morelos State, south central Mexico

2020 ◽  
Vol 37 (1) ◽  
pp. 1-8
Author(s):  
Rocío García-Martínez ◽  
Alejandro Carrillo-Chavez ◽  
Ricardo Torres-Jardón ◽  
Alejandro Ramirez-Guzmán ◽  
Moisés López-Carrasco
Keyword(s):  
Chemical Composition ◽  
Mexico City ◽  
Atmospheric Transport ◽  
Sampling Site ◽  
Air Pollutant ◽  
Rural Site ◽  
Central Mexico ◽  
Strong Positive Correlation ◽  
Back Trajectories ◽  
South Central

The objective of the study was to evaluate the chemical composition of rainwater in urban and suburban areas of central Mexico to identify the possible sources of rainwater contamination. The rainwater was collected at Universidad Nacional Autónoma de Mexico, Campus Ciudad Universitaria (CU), in the southern part of Mexico City at 2200 meters above sea level (m a.s.l.). CU has many green areas with high to moderate traffic densities where air quality presents serious problems of pollution by particulate matter. The other sampling site is a forested rural area (Tlalnepantla), State of Morelos, Mexico, a suburban area 86 km to the south of Mexico City. A total of 145 rainwater samples were collected in the rain period from 2006 to 2009. The ions analyzed were the following: SO42-, NO3-, Cl-, HCO3-, Na+, K+, Ca2+, Mg2+, NH4+ and H+. Ammonium was the most abundant cation in both sites and is one of those responsible for the neutralization of acidic compounds in the atmosphere. The relative abundance of the inorganic anions present in the rainwater was in the following order: SO42- > NO3- > Cl-, for the alkaline metals the order was Ca2+ >Mg2+ > Na+ > K+ and Ca2+ >Mg2+ >K+ >Na+ for CU and Morelos, respectively. A correlation analysis shows a strong positive correlation among the ions, indicating that the most important source was anthropogenic. Air mass back trajectories were associated with the SO42-, Ca2+, Mg2+, NH4+ and H+ concentrations observed on each rainy day. Four factors were used in the statistic analysis and was weighted within each factor. Weights greater than 0.5 are considered to be significant components of each factor. The four factors explain 84.7 % of the total variance of all of the data for CU and 66.9 % for Morelos. All of these factors were associated with all of the analyzed ions. Air pollutant back trajectories were used to understand atmospheric transport and to identify the origins and pathways of air masses influencing the concentrations of the measured ions in rainwater.

scholarly journals Identification of PM10 air pollution origins at a rural background site

2018 ◽  
Vol 28 ◽  
pp. 01031 ◽  
Author(s):  
Magdalena Reizer ◽  
José A. G. Orza
Keyword(s):  
Air Pollution ◽  
Cluster Analysis ◽  
Hysplit Model ◽  
Back Trajectories ◽  
Air Masses ◽  
Rural Background ◽  
Central Eastern Europe ◽  
Background Site ◽  
North Eastern ◽  
Slow Moving

Trajectory cluster analysis and concentration weighted trajectory (CWT) approach have been applied to investigate the origins of PM10 air pollution recorded at a rural background site in North-eastern Poland (Diabla Góra). Air mass back-trajectories used in this study have been computed with the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model for a 10-year period of 2006–2015. A cluster analysis grouped back-trajectories into 7 clusters. Most of the trajectories correspond to fast and moderately moving westerly and northerly flows (45% and 25% of the cases, respectively). However, significantly higher PM10 concentrations were observed for slow moving easterly (11%) and southerly (20%) air masses. The CWT analysis shows that high PM10 levels are observed at Diabla Góra site when air masses are originated and passed over the heavily industrialized areas in Central-Eastern Europe located to the south and south-east of the site.

scholarly journals Cupressaceae Pollen in the City of Évora, South of Portugal: Disruption of the Pollen during Air Transport Facilitates Allergen Exposure

Forests ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 64
Author(s):  
Ana Galveias ◽  
Ana R. Costa ◽  
Daniele Bortoli ◽  
Russell Alpizar-Jara ◽  
Rui Salgado ◽  
...  
Keyword(s):  
Wind Speed ◽  
Ornamental Plants ◽  
Global Solar Radiation ◽  
Early Spring ◽  
Back Trajectory ◽  
Late Winter ◽  
Hysplit Model ◽  
Back Trajectories ◽  
Factors Affecting ◽  
Back Trajectory Analysis

Research Highlights: Daily airborne Cupressaceae pollen disruption ranged from 20 to 90%; relative humidity (RH), rainfall and atmospheric pressure (AtP) were the major meteorological determinants of this phenomenon. Background and Objectives: Cupressaceae family includes several species that are widely used as ornamental plants pollinating in late winter-early spring and might be responsible for allergic outbreaks. Cupressaceae pollen disruption may favour allergen dissemination, potentiating its allergenicity. The aim of this work was to characterize the Cupressaceae pollen aerobiology in Évora, South of Portugal, in 2017 and 2018, particularly the pollen disruption, and to identify the meteorological parameters contributing to this phenomenon. Materials and Methods: Pollen was collected using a Hirst type 7-day pollen trap and was identified following the standard methodology. Temperature, RH, rainfall, global solar radiation (Global Srad), AtP, wind speed and direction were obtained from a weather station installed side-by-side to the Hirst platform. Back trajectories (12-h) of air masses arriving at Évora were calculated using the HYSPLIT model. Results: Cupressaceae pollen index was higher in 2017 compared to 2018 (>5994 and 3175 pollen/m3, respectively) and 36 ± 19% (2017) and 59 ± 23% (2018) of the pollen was disrupted. Higher levels of disrupted pollen coincided with RH > 60% and rainfall. Temperature, Global Srad and AtP correlated negatively with pollen disruption. Wind speed and wind direction did not significantly correlate with pollen disruption. Intra-diurnal pollen pattern peaked between 9:00 am–2:00 pm, suggesting local origin, confirmed by the back trajectory analysis. Intra-diurnal pollen disruption profile followed hourly pollen pattern and it negatively correlated with AtP, temperature and Global Srad but was uncorrelated with RH. Conclusions: The results suggest that RH, rainfall and AtP are the main factors affecting airborne Cupressaceae pollen integrity and in conjunction with daily pollen concentration may be used to predict the risk of allergy outbreaks to this pollen type.

scholarly journals River Breezes for Pollutant Dispersion in GoAmazon2014/5

2018 ◽  
Author(s):  
Adan S. S. Medeiros ◽  
Igor O. Ribeiro ◽  
Marcos V. B. Morais ◽  
Rita V. Andreoli ◽  
Jorge A. Martins ◽  
...  
Keyword(s):  
Pollutant Dispersion ◽  
Atmospheric Composition ◽  
Horizontal Wind ◽  
Data Sets ◽  
Plume Dispersion ◽  
Wind Fields ◽  
Wind Speeds ◽  
Pollutant Concentrations ◽  
First Case ◽  
Apparent Influence

Abstract. The effect of river breezes on pollutant plume dispersion or canalization in the central Amazon was evaluated. A pollution plume changes atmospheric composition downwind of Manaus, a city of 2 million people positioned at the confluence between two wide rivers. Herein, to evaluate the effects of river breezes, two cases were modeled at the mesoscale for March 2014. The first case, "with rivers" (wR), simulated the transport and chemistry of the Manaus pollution plume as the rivers were in reality. The second case, "without rivers" (woR), carried out simulations for which all rivers and floodable areas were replaced by forest. The three main conclusions are as follows: (1) Between the two cases, alterations in wind speeds were maximum at local noon, and river breezes influenced horizontal wind fields from surface up to 150 m in altitude, suggesting a capping height of 150 m on most days for the influence of river breezes on pollutant concentrations. In agreement with this modeling result, data sets collected at 500 m by aircraft flights showed no apparent influence of the underlying rivers on plume dispersion. The flights traversed the plume downwind of Manaus during the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) Experiment. (2) Between the wR and wOR cases, changes to downwind concentrations of O3, NOx, and CO pollutants were

scholarly journals Analysis of air mass back trajectories with present and historical volcanic activity and anthropogenic compounds to infer pollution sources in the South Shetland Islands (Antarctica)

2018 ◽  
Vol 15 (1) ◽  
pp. 111-137 ◽  
Author(s):  
Danuta Szumińska ◽  
Sebastian Czapiewski ◽  
Małgorzata Szopińska ◽  
Żaneta Polkowska
Keyword(s):  
South America ◽  
Atmospheric Transport ◽  
Anthropogenic Pollution ◽  
South Shetland Islands ◽  
Eastern Coast ◽  
The South ◽  
Hysplit Model ◽  
Air Mass ◽  
Back Trajectories ◽  
Shetland Islands

Abstract This work analyses atmospheric transport of natural and anthropogenic pollution to the South Shetland Islands (SSI), with particular reference to the period September 2015 – August 2017. Based on data from the Global Volcanism Program database and air mass back trajectories calculated using the HySPLIT model, it was found that it is possible that in the analysed period volcanic pollution was supplied via long-range transport from South America, and from the South Sandwich Islands. Air masses flowed in over the South Shetland Islands from the South America region relatively frequently – 226 times during the study period, which suggests the additional possibility of anthropogenic pollution being supplied by this means. In certain cases the trajectories also indicated the possibility of atmospheric transport from the New Zealand region, and even from the south-eastern coast of Australia. The analysis of the obtained results is compared against the background of research by other authors. This is done to indicate that research into the origin of chemical compounds in the Antarctic environment should take into account the possible influx of pollutants from remote areas during the sampling period, as well as the possible reemission of compounds accumulated in snow and ice.

scholarly journals Analysis of a low ozone episode over Extremadura (Spain) in January 2006 and its influence on UV radiation

2008 ◽  
Vol 2 (1) ◽  
pp. 17-20 ◽  
Author(s):  
M. Antón ◽  
M. L. Cancillo ◽  
A. Serrano ◽  
J. A. García ◽  
F. J. Acero
Keyword(s):  
Uv Radiation ◽  
Developmental Stages ◽  
Mean Value ◽  
Terrestrial Plants ◽  
Hysplit Model ◽  
Back Trajectories ◽  
Notable Increase ◽  
Western Spain ◽  
To Receive ◽  
Early Developmental

Abstract. The main objectives of this work are to analyze, firstly, the detail of the causes of a low ozone event which occurred in January 2006 and, secondly, the related effects of this anomalous episode on ultraviolet (UV) radiation measured at three locations in Extremadura (South-Western Spain). On 19 January 2006, the OMI total ozone column (TOC) was 16–20% below the January mean value of TOMS/NASA TOC (period 1996–2005). The back trajectories analysis with the HYSplit model indicates that the notable decrease of TOC could be attributed to a fast rise of the isentropic trajectories height. Concomitantly, UV erythemal radiation greatly increases (between 23% and 37%) on 19 January 2006 respect to UV erythemal radiation measured on 19 January 2005. This notable increase in winter UV solar radiation may involve harmful effects for organisms adapted to receive less radiation during that season (e.g. early developmental stages of terrestrial plants and phytoplankton).

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