scholarly journals Evaluation of MODIS aerosol retrieval algorithms over the Beijing‐Tianjin‐Hebei region during low to very high pollution events

2015 ◽  
Vol 120 (15) ◽  
pp. 7941-7957 ◽  
Author(s):  
Muhammad Bilal ◽  
Janet E. Nichol
Keyword(s):  
Aerosol Retrieval ◽  
Retrieval Algorithms ◽  
High Pollution ◽  
Pollution Events ◽  
Very High

scholarly journals Modeling heavy metal release in the epiphytic lichen Evernia prunastri

2021 ◽  
Author(s):  
Andrea Vannini ◽  
Luca Paoli ◽  
Riccardo Fedeli ◽  
Sharon Kwambai Kangogo ◽  
Massimo Guarnieri ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Remote Area ◽  
Metal Release ◽  
Evernia Prunastri ◽  
Epiphytic Lichen ◽  
Pollution Levels ◽  
Short Period ◽  
High Pollution ◽  
Heavy Metal Release ◽  
Very High

AbstractIn this study, the release of Cu2+ and Zn2+ was investigated and modeled in the epiphytic lichen Evernia prunastri. Samples were incubated with solutions containing these metals at ecologically relevant concentrations (10 and 100 μM) and then transplanted to a remote area and retrieved after 1, 2, 3, 6, 12, and 18 months. The results showed that, after 12 months, all samples faced similar metal reductions of ca. 80–85%, but after this period, all the involved processes seem to be no longer capable of generating further reductions. These results suggest that the lichen E. prunastri can provide information about environmental improvements after exposure to high or very high pollution levels in a relatively short period of time.

scholarly journals Evaluation of NASA Deep Blue/SOAR aerosol retrieval algorithms applied to AVHRR measurements

2017 ◽  
Vol 122 (18) ◽  
pp. 9945-9967 ◽  
Author(s):  
A. M. Sayer ◽  
N. C. Hsu ◽  
J. Lee ◽  
N. Carletta ◽  
S.-H. Chen ◽  
...  
Keyword(s):  
Deep Blue ◽  
Aerosol Retrieval ◽  
Retrieval Algorithms

scholarly journals Assessment of the Toxic Elements Resulting from the Manufacture of Bricks on Air and Soil at Abu Smeache Area - Southwest Babylon governorate - Iraq

2019 ◽  
pp. 2443-2456
Author(s):  
Murtadha J. Issa ◽  
Hussain Musa Hussain ◽  
Inas Hadi Shaker
Keyword(s):  
Suspended Particles ◽  
Soil Samples ◽  
Fuel Oil ◽  
Heavy Elements ◽  
Total Suspended Particles ◽  
High Pollution ◽  
Different Depths ◽  
The Impact ◽  
Very High ◽  
Slight Contamination

     Brick factories distributed within the study area use fuel oil to complete the burning of the bricks, were high amounts of gases and suspended particles with different concentrations of heavy elements are produced and cause air and soil pollution. It is noted that the workers suffer from respiratory diseases and other health problems. This study is an attempt to detect the sources and concentrations of pollutants and to propose modalities for their treatment and reduction. Air and soil samples were collected from different sites in Abu Smeache brick factory in Al-Kifl area to the south of Babel city, Iraq, during two seasons (summer and winter). The process also included collecting and modelling of dust and soil samples from two depth, surface and sub-surface, to detect pollution and the mobility of heavy elements across the different depths. Heavy elements (Pb, Ni, Co), along with gases (CO, CO2, NO2, SO2) and total suspended particles (TSP) in the air, were analyzed by atomic absorption spectroscopy. The air results showed high pollution with all the studied heavy elements, while the levels of TSP and SO2 were higher than global and Iraqi limits in most of the studied stations, especially in the winter. The results also showed significant pollution in the soil with lead along with slight contamination with nickel and cobalt. Soil contamination was evaluated using several contamination indices; the values of contamination factors (CF) for the lead were very high, while CF values for nickel and copper indicated low to moderate pollution. Also, the high values of PLI ˃1 in the soil indicated high pollution with heavy elements, which provides clear evidence of the impact of industrial human activities on the environment of the region. In addition, low values of i-geo indicated a moderate contamination with lead and an unpolluted status for both nickel and copper. These results indicate a great need to develop strategies to prevent and reduce pollution by heavy metals in  the areas under rapid industrial and urban development.

scholarly journals Change of Ba concentration by species and organ in several fruits grown in city centers

2021 ◽  
Vol 12 (3) ◽  
pp. 143-150
Author(s):  
Halil Baris Ozel ◽  
Mesut Sen ◽  
Hakan Sevik
Keyword(s):  
Heavy Metals ◽  
Prunus Avium ◽  
Heavy Metal Concentration ◽  
Prunus Cerasus ◽  
Traffic Density ◽  
High Pollution ◽  
Tilia Tomentosa ◽  
High Traffic Density ◽  
Very High ◽  
Significant Health

Heavy metals are elements that are very harmful to human and environmental health. Heavy metal concentration in the fruits grown in city centers can reach very high levels and consuming these fruits as food causes a direct intake of heavy metals, which these fruits contain, into a human body and can pose a significant health risk. All the compounds of barium (Ba), which is one of the most dangerous heavy metals, are toxic. Thus, determining the Ba concentration in plants, which are grown in areas with high pollution and consumed as food, is very important. In the present study, it was aimed to determine the change of Ba concentration by species and organ in several fruits grown in areas with high traffic density. Within the scope of this study, Ba concentrations in leaf, branch, bark, seed, and fruits of Prunus ceresifera, Tilia tomentosa, Prunus avium, and Prunus cerasus were compared. As a result, it was determined that the change of Ba concentrations by species and the change by organ were statistically significant in all organs and in all species, respectively. In general, the lowest values were found in Prunus cerasus or Prunus avium, whereas the highest values were observed in Tilia tomentosa. Considering the organs, the lowest values were found in seed and the highest ones in bark and branch.

scholarly journals Multi-sensor cloud and aerosol retrieval simulator and remote sensing from model parameters – Part 2: Aerosols

2016 ◽  
Vol 9 (7) ◽  
pp. 2377-2389 ◽  
Author(s):  
Galina Wind ◽  
Arlindo M. da Silva ◽  
Peter M. Norris ◽  
Steven Platnick ◽  
Shana Mattoo ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Weather Prediction ◽  
Retrieval Algorithm ◽  
Model Parameters ◽  
Aerosol Retrieval ◽  
Model Aerosol ◽  
Numerical Experimentation ◽  
Retrieval Algorithms ◽  
Sensor Cloud ◽  
Aerosol Properties

Abstract. The Multi-sensor Cloud Retrieval Simulator (MCRS) produces a “simulated radiance” product from any high-resolution general circulation model with interactive aerosol as if a specific sensor such as the Moderate Resolution Imaging Spectroradiometer (MODIS) were viewing a combination of the atmospheric column and land–ocean surface at a specific location. Previously the MCRS code only included contributions from atmosphere and clouds in its radiance calculations and did not incorporate properties of aerosols. In this paper we added a new aerosol properties module to the MCRS code that allows users to insert a mixture of up to 15 different aerosol species in any of 36 vertical layers.This new MCRS code is now known as MCARS (Multi-sensor Cloud and Aerosol Retrieval Simulator). Inclusion of an aerosol module into MCARS not only allows for extensive, tightly controlled testing of various aspects of satellite operational cloud and aerosol properties retrieval algorithms, but also provides a platform for comparing cloud and aerosol models against satellite measurements. This kind of two-way platform can improve the efficacy of model parameterizations of measured satellite radiances, allowing the assessment of model skill consistently with the retrieval algorithm. The MCARS code provides dynamic controls for appearance of cloud and aerosol layers. Thereby detailed quantitative studies of the impacts of various atmospheric components can be controlled.In this paper we illustrate the operation of MCARS by deriving simulated radiances from various data field output by the Goddard Earth Observing System version 5 (GEOS-5) model. The model aerosol fields are prepared for translation to simulated radiance using the same model subgrid variability parameterizations as are used for cloud and atmospheric properties profiles, namely the ICA technique. After MCARS computes modeled sensor radiances equivalent to their observed counterparts, these radiances are presented as input to operational remote-sensing algorithms.Specifically, the MCARS-computed radiances are input into the processing chain used to produce the MODIS Data Collection 6 aerosol product (M{O/Y}D04). The M{O/Y}D04 product is of course normally produced from M{O/Y}D021KM MODIS Level-1B radiance product directly acquired by the MODIS instrument. MCARS matches the format and metadata of a M{O/Y}D021KM product. The resulting MCARS output can be directly provided to MODAPS (MODIS Adaptive Processing System) as input to various operational atmospheric retrieval algorithms. Thus the operational algorithms can be tested directly without needing to make any software changes to accommodate an alternative input source.We show direct application of this synthetic product in analysis of the performance of the MOD04 operational algorithm. We use biomass-burning case studies over Amazonia employed in a recent Working Group on Numerical Experimentation (WGNE)-sponsored study of aerosol impacts on numerical weather prediction (Freitas et al., 2015). We demonstrate that a known low bias in retrieved MODIS aerosol optical depth appears to be due to a disconnect between actual column relative humidity and the value assumed by the MODIS aerosol product.

scholarly journals Inter-comparison of three AATSR Level 2 (L2) AOD products over China

2016 ◽  
Author(s):  
Y. Che ◽  
Y. Xue ◽  
L. Mei ◽  
J. Guang ◽  
H. Xu ◽  
...  
Keyword(s):  
Mainland China ◽  
Western China ◽  
Mean Bias Error ◽  
Retrieval Algorithm ◽  
Bias Error ◽  
Aerosol Retrieval ◽  
Retrieval Algorithms ◽  
Level 3 ◽  
The Stability ◽  
Level 2

Abstract. The Advanced Along-Track Scanning Radiometer (AATSR) aboard on ENVISAT is used to observe the Earth by dual-view. The AATSR data can be used to retrieve aerosol optical depth (AOD) over both land and ocean, which is an important merit in the characterization of aerosol properties. In recent years, aerosol retrieval algorithms both over land and ocean have been developed, taking advantages of the feature of dual-view which can help eliminate contribution of Earth's surface to top of atmosphere (TOA) reflectance. Aerosol_cci project as a part of Climate Change Initiative (CCI) provides users three AOD retrieval algorithms for AATSR data, including the Swansea algorithm (SU), the ATSR-2ATSR dual view aerosol retrieval algorithm (ADV) and the Oxford-RAL Retrieval of Aerosol and Cloud algorithm (ORAC). The Validation team of Aerosol-CCI project has validated AOD (both Level 2 and Level 3 products) and AE (Level 2 product only) against the AERONET data in a round robin evaluation using validation tool of AeroCOM (Aerosol Comparison between Observations and Models) project. For the purpose of evaluating different performances of these three algorithms on calculating AODs over mainland China, we introduce ground-based data from the CARSNET (the China Aerosol Remote Sensing Network) which is designed for aerosol observation in China. Because China is vast in territory and of great differences in surface, the combination of the AEROENT and the CATRNET data can validate L2 AOD products more comprehensively. The validation results show different performances of these products in 2007, 2008 and 2010. The SU algorithm has very good performance over sites with different surface conditions in mainland China from March to October, but it underestimates AOD slightly with varying mean bias error (MBE) from 0.05 to 0.10 over surface of barren or sparsely vegetation in western China. The ADV product has same precision with high correlation coefficient (CC) larger than 0.90 over most of sites and same error distribution as the SU product. The main limits of ADV algorithm are underestimation and applicability, especially it occurs obvious underestimation over sites of Datong, Lanzhou and Urmuchi where the dominated land cover is grassland with MBE larger than 0.2 and the main source of aerosol is coal combustion and dust. The ORAC algorithm has the ability of retrieving AOD at different ranges including high AOD (larger than 1.0), however, the stability will decease significantly as AOD grows, especially when AOD > 1.0. In addition, ORAC product get matches successfully collocated with CARSNET in winter (December, January and February), whereas other validation results lack matches during winter.

scholarly journals Retrieval of aerosol optical depth over land surfaces from AVHRR data

2013 ◽  
Vol 6 (1) ◽  
pp. 2227-2251 ◽  
Author(s):  
L. Mei ◽  
Y. Xue ◽  
A. A. Kokhanovsky ◽  
W. von Hoyningen-Huene ◽  
G. de Leeuw ◽  
...  
Keyword(s):  
Time Series ◽  
High Resolution ◽  
Aerosol Optical Depth ◽  
Optical Depth ◽  
Surface Reflectance ◽  
Aerosol Retrieval ◽  
Avhrr Data ◽  
Land Surfaces ◽  
Very High

Abstract. The Advanced Very High Resolution Radiometer (AVHRR) radiance data provide a global, long-term, consistent time series having high spectral and spatial resolution and thus being valuable for the retrieval of surface spectral reflectance, albedo and surface temperature. Long term time series of such data products are necessary for studies addressing climate change, sea ice distribution and movement, and ice sheet coastal configuration. These data have also been used to retrieve aerosol properties over ocean and land surfaces. However, the retrieval of aerosol over land and land surface albedo are challenging because of the information content of the measurement is limited and the inversion of these data products being ill defined. Solving the radiative transfer equations requires additional information and knowledge to reduce the number of unknowns. In this contribution we utilise an empirical linear relationship between the surface reflectances in the AVHRR channels at wavelengths of 3.75 μm and 2.1 μm, which has been identified in Moderate Resolution Imaging Spectroradiometer (MODIS) data. Next, following the MODIS dark target approach, the surface reflectance at 0.64 μm was obtained. The comparison of the estimated surface reflectance at 0.64 μm with MODIS reflectance products (MOD09) shows a strong correlation (R = 0.7835). Once this was established, the MODIS "dark-target" aerosol retrieval method was adapted to Advanced Very High Resolution Radiometer (AVHRR) data. A simplified Look-Up Table (LUT) method, adopted from Bremen AErosol Retrieval (BAER) algorithm, was used in the retrieval. The Aerosol Optical Depth (AOD) values retrieved from AVHRR with this method compare favourably with ground-based measurements, with a correlation coefficient R = 0.861 and Root Mean Square Error (RMSE) = 0.17. This method can be easily applied to other satellite instruments which do not have a 2.1 μm channel, such as those currently planned to geostationary satellites.

Isotope-Based Source Apportionment of EC Aerosol Particles during Winter High-Pollution Events at the Zeppelin Observatory, Svalbard

2015 ◽  
Vol 49 (19) ◽  
pp. 11959-11966 ◽  
Author(s):  
Patrik Winiger ◽  
August Andersson ◽  
Karl E. Yttri ◽  
Peter Tunved ◽  
Örjan Gustafsson
Keyword(s):  
Source Apportionment ◽  
Aerosol Particles ◽  
High Pollution ◽  
Pollution Events
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