scholarly journals Inventory of African desert dust events in the north-central Iberian Peninsula in 2003–2014 based on sun-photometer–AERONET and particulate-mass–EMEP data

2016 ◽  
Vol 16 (13) ◽  
pp. 8227-8248 ◽  
Author(s):  
Victoria E. Cachorro ◽  
Maria A. Burgos ◽  
David Mateos ◽  
Carlos Toledano ◽  
Yasmine Bennouna ◽  
...  
Keyword(s):  
Mineral Dust ◽  
Human Observer ◽  
North Central ◽  
Desert Dust ◽  
The North ◽  
Western Mediterranean Basin ◽  
Synoptic Conditions ◽  
Particulate Mass ◽  
Sun Photometer ◽  
The Impact

Abstract. A reliable identification of desert dust (DD) episodes over north-central Spain is carried out based on the AErosol RObotic NETwork (AERONET) columnar aerosol sun photometer (aerosol optical depth, AOD, and Ångström exponent, α) and European Monitoring and Evaluation Programme (EMEP) surface particulate-mass concentration (PMx, x = 10, 2.5, and 2.5–10 µm) as the main core data. The impact of DD on background aerosol conditions is detectable by means of aerosol load thresholds and complementary information provided by HYSPLIT (Hybrid Single Particle Lagrangian Integrated Trajectory Model) air mass back trajectories, MODIS (Moderate Resolution Imaging Spectroradiometer) images, forecast aerosol models, and synoptic maps, which have been carefully reviewed by a human observer for each day included in the DD inventory. This identification method allows the detection of low and moderate DD intrusions and also of mixtures of mineral dust with other aerosol types by means of the analysis of α. During the period studied (2003–2014), a total of 152 DD episodes composed of 418 days are identified. Overall, this means ∼ 13 episodes and ∼ 35 days per year with DD intrusion, representing 9.5 % days year−1. During the identified DD intrusions, 19 daily exceedances over 50 µg m−3 are reported at the surface. The occurrence of DD event days during the year peaks in March and June, with a marked minimum in April and lowest occurrence in winter. A large interannual variability is observed showing a statistically significant temporal decreasing trend of ∼ 3 days year−1. The DD impact on the aerosol climatology is addressed by evaluating the DD contribution in magnitude and percent (in brackets) for AOD, PM10, PM2.5, and PM2.5 − 10, obtaining mean values of 0.015 (11.5 %), 1.3 µg m−3 (11.8 %), 0.55 µg m−3 (8.5 %) and 0.79 µg m−3 (16.1 %), respectively. Annual cycles of the DD contribution for AOD and PM10 present two maxima – one in summer (0.03 and 2.4 µg m−3 for AOD in June and PM10 in August) and another in March (0.02 for AOD and 2.2 µg m−3 for PM10) – both displaying a similar evolution with exceptions in July and September. The seasonal cycle of the DD contribution to AOD does not follow the pattern of the total AOD (close to a bell shape), whereas both PM10 cycles (total and DD contribution) are more similar to each other in shape, with an exception in September. The interannual evolution of the DD contribution to AOD and PM10 has evidenced a progressive decrease. This decline in the levels of mineral dust aerosols can explain up to 30 % of the total aerosol load decrease observed in the study area during the period 2003–2014. The relationship between columnar and surface DD contribution shows a correlation coefficient of 0.81 for the interannual averages. Finally, synoptic conditions during DD events are also analysed, observing that the north African thermal low causes most of the events ( ∼  53 %). The results presented in this study highlight the relevance of the area studied since it can be considered representative of the clean background in the western Mediterranean Basin where DD events have a high impact on aerosol load levels.

scholarly journals INVENTORY OF AFRICAN DESERT DUST EVENTS IN THE NORTH-CENTRAL IBERIAN PENINSULA IN 2003–2014 BASED ON SUNPHOTOMETER-AERONET AND PARTICULATE MASS-EMEP DATA

2016 ◽  
Author(s):  
V. E. Cachorro ◽  
M. A. Burgos ◽  
D. Mateos ◽  
C. Toledano ◽  
Y. Bennouna ◽  
...  
Keyword(s):  
Mineral Dust ◽  
Western Mediterranean ◽  
Human Observer ◽  
North Central ◽  
Desert Dust ◽  
The North ◽  
Western Mediterranean Basin ◽  
Synoptic Conditions ◽  
Particulate Mass ◽  
The Impact

Abstract. A reliable identification of Desert Dust (DD) episodes over North-central Spain is carried out based on AErosol RObotic NETwork (AERONET) columnar aerosol sun-photometer (aerosol optical depth, AOD, and Ångström exponent, α) and European Monitoring and Evaluation Programme (EMEP) surface particulate mass concentration (PMx, x = 10, 2.5, and 2.5–10 µm) as main core data. The impact of DD on background aerosol conditions is detectable by means of aerosol load thresholds and complementary information provided by HYSPLIT (Hybrid Single Particle Lagrangian Integrated Trajectory Model) air mass back-trajectories, MODIS (Moderate Resolution Imaging Spectroradiometer) images, forecasting aerosol models, and synoptic maps, which had been carefully reviewed by a human observer for each day included in the DD inventory. This identification method allows the detection of low and moderate DD intrusions and also mixtures of mineral dust with other aerosol types by means of the analysis of α. During the period studied (2003–2014), a total of 152 DD episodes composed of 419 days are identified. Overall, this means ~ 13 episodes and ~ 35 days per year with DD intrusion, representing 9.6 % days/year. During the identified DD outbreaks, 19 daily exceedances over 50 µg m−3 are reported at the surface. The occurrence of DD event days along the year peaks in March and June with a marked minimum in April and lowest occurrence in winter. A large inter-annual variability is observed showing a statistically significant temporal decreasing trend of ~3 days/year. As a key point, the DD impact on the aerosol climatology is addressed by evaluating the DD contribution to AOD, PM10, PM2.5, and PM2.5–10 obtaining mean values of 0.015 (11.5 %), 1.3 µg m−3 (11.8 %), 0.55 µg m−3 (8.5 %) and 0.79 µg m−3 (16.1 %), respectively. Almost similar annual cycles of DD contribution are obtained for AOD and PM10 with two maxima, one in summer (0.03 and 2.4 µg m−3 for AOD in June and PM10 in August, respectively) and another in March (0.02 for AOD and 2.2 µg m−3 for PM10), discrepancies occurring only in July and September. It is worth mentioning that the seasonal cycle of DD contribution to AOD does not follow the pattern of the total AOD (near bell shape), meanwhile both PM10 cycles (total and DD contribution) present more similar shapes between them, although a main discrepancy is observed in September. The inter-annual evolution of the DD contribution to AOD and PM10 has evidenced a progressive decrease. This decline in the levels of natural mineral dust aerosols can explain up to the 30 % of the total aerosol load decrease observed in the study area during the period 2003–2014. The relationship between columnar and surface DD contributions is evident with a correlation coefficient of 0.81 for the inter-annual averages. Finally, synoptic conditions during DD events are also analysed observing that the North African thermal low causes most of the events (~ 53 %). The results presented in this study highlight the relevance of the area studied since it can be considered as representative of the clean background in Western Mediterranean Basin where DD events have a high impact on aerosol load levels.

A Synoptic Study on the Formation of Squall Lines in the North Central United States

1955 ◽  
Vol 36 (8) ◽  
pp. 390-396 ◽  
Author(s):  
John M. Porter ◽  
L. L. Means ◽  
J. E. Hovde ◽  
W. B. Chappell
Keyword(s):  
United States ◽  
Squall Line ◽  
Line Formation ◽  
Check List ◽  
North Central ◽  
The North ◽  
Squall Lines ◽  
Synoptic Conditions ◽  
Central United States

The aim of this study was to discover synoptic conditions which favored squall-line formation in the north-central United States. The squall lines over approximately a three-year period were classified into three types and studied using charts from the surface to 200 mb. Although the various parameters were not reduced to a strictly objective technique, a check list of significant parameters was prepared for the use and guidance of forecasters. It is believed that this check sheet will help the forecaster in forecasting squall-line development in the north-central United States.

scholarly journals The Influence of Habitat Changes on Elephant Mortality Associated with Human–Elephant Conflict: Identifying Areas of Concern in the North Central Dry Zone of Sri Lanka

2021 ◽  
Vol 13 (24) ◽  
pp. 13707
Author(s):  
Chase A. LaDue ◽  
Sarah M. Farinelli ◽  
Imira Eranda ◽  
Chandana Jayasinghe ◽  
Rajnish P. G. Vandercone
Keyword(s):  
Sri Lanka ◽  
Habitat Quality ◽  
Human Activity ◽  
Human Population ◽  
Forest Cover ◽  
North Central ◽  
The North ◽  
Dry Zone ◽  
The Impact ◽  
Forest Cover Loss

Human–wildlife conflict (HWC) is becoming increasingly prevalent as human activity expands, and monitoring the impact of habitat quality on wildlife mortality related to HWC is critical for the well-being of wildlife and people. Using ten years of necropsies from free-ranging Asian elephants in the Northwestern Wildlife Region (NWR) of Sri Lanka, we quantified the effect of habitat quality on human–elephant conflict (HEC) (i.e., human-caused elephant mortality), hypothesizing that both artificial (e.g., forest cover loss) and natural (e.g., water availability, temperature) changes would be associated with elephant mortality. We collated necropsies from 348 elephants that died due to human activity from 2009 to 2018, comparing the results with data on forest cover loss, perennial water, rainfall, temperature, and human population sizes. Over the study period, we found that forest cover loss was significantly correlated with human-caused mortality in a district-specific manner. Similarly, access to perennial water and precipitation levels appeared to influence mortality, but not temperature, human population density, or percent land cover used for agriculture. We conducted emerging hot spot analyses to identify areas within the NWR that should be prioritized for protection, which included landscapes that are not currently protected (approximately 43% of the hot spots we identified). Similarly, areas that we identified as cold spots included many areas with minimal forest cover loss. Together, our results emphasize the impact that human activity can have on the measurable outcomes of HEC. We suggest that adaptive HWC management strategies that use retrospective analyses should inform any potential changes to the protection of vital wildlife habitats, such as the north central dry zone of Sri Lanka.

scholarly journals Simulation of impact of organic and nutrient pollutants from Nghi Son economic zone on Thanh Hoa coastal waters, North Centre Vietnam

2021 ◽  
Vol 21 (1) ◽  
pp. 23-36
Author(s):  
Hai Nguyen Minh ◽  
Vinh Vu Duy
Keyword(s):  
Coastal Waters ◽  
Current Status ◽  
North Central ◽  
Waste Discharge ◽  
The North ◽  
Pollutant Concentrations ◽  
Numeric Modeling ◽  
Economic Zone ◽  
Surrounding Areas ◽  
The Impact

Nghi Son is an economic zone oriented to developing heavy industry and petrochemicals and has potential to become the most substantial economic zone in the North Central region. The zone is also one of the potential waste sources polluting Thanh Hoa coastal waters. Numeric modeling using Delft3D software package with different scenarios: Current status scenario, controlled discharge scenario, and incident scenario was developed to simulate states of some pollutants of organics and nutrients from the zone to Thanh Hoa coastal waters in different periods. The simulation results show that under controlled discharge (increasing pollutant concentration with the control of waste discharge), the concentration of pollutants was increasing and high around discharging points. In contrast, in incident case from the zone, pollutant concentrations increase markedly both in the magnitude and in the impact range to surrounding areas. When an accident happens, the influence scale will be expanded significantly, especially in the rainy season.

scholarly journals Relationships between columnar aerosol optical properties and surface particulate matter observations in north-central Spain from long-term records (2003–2011)

2014 ◽  
Vol 7 (6) ◽  
pp. 5829-5882 ◽  
Author(s):  
Y. S. Bennouna ◽  
V. Cachorro ◽  
M. A. Burgos ◽  
C. Toledano ◽  
B. Torres ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Annual Cycle ◽  
Central Area ◽  
Central Spain ◽  
North Central ◽  
Desert Dust ◽  
The North ◽  
Daily Data ◽  
Dust Events

Abstract. This work examines the relationships between Aerosol Optical Depth (AOD) and Particulate Matter (PMX) parameters, based on long records (2003–2011) of two nearby sites from the AERONET and EMEP networks in the north-central area of Spain. The climatological annual cycle of PM10 and PM2.5 present a bimodality which might be partly due to desert dust intrusions, a pattern which does not appear in the annual cycle of the AOD. In the case of the AOD, this bimodality is likely to be masked because of the poor sampling of sunphotometer data as compared to PMX (67% of days against 90%), and this fact stresses the necessity of long-term observations. In monthly series, significant interannual variations are observed and most extrema coincide, however the bimodal shape remains relatively stable for PMX. Significant and consistent trends were found for both datasets likely associated to a decrease of desert dust apportionment until 2009. PM10 and AOD daily data are moderately correlated (0.56), a correlation improving for monthly means (0.70). In the case of strong desert dust events day-to-day correlation is not systematic, therefore an extensive analysis on PMX, fine-PM ratio, AOD and associated Ångström exponent (α) is carried out.

scholarly journals Analyses of Yield and Economic Response from Foliar Fungicide and Insecticide Applications to Soybean in the North Central United States

2016 ◽  
Vol 17 (4) ◽  
pp. 232-238 ◽  
Author(s):  
Yuba R. Kandel ◽  
Daren S. Mueller ◽  
Chad E. Hart ◽  
Nathan R. C. Bestor ◽  
Carl A. Bradley ◽  
...  
Keyword(s):  
United States ◽  
Field Experiments ◽  
Foliar Application ◽  
The United States ◽  
Insect Management ◽  
North Central ◽  
The North ◽  
Central United States ◽  
Foliar Fungicide ◽  
The Impact

Foliar disease and insect management on soybean (Glycine max L. Merrill) in the North Central region of the United States has been increasingly accomplished through foliar fungicide and insecticide application. Data from research trials conducted in Illinois, Indiana, Iowa, and Nebraska were compiled from 2008 to 2014 to determine the impact of fungicide, insecticide, and fungicide + insecticide applications on soybean yield and profitability. In each state, field experiments occurred each year in two to seven locations. All treatments were applied at the R3 growth stage. Disease and insect pressure were very low in all states and years. A foliar application of fungicide, insecticide, or the combination, increased yield in seven out of 14 total site-years (P < 0.10). Economic analysis using an average soybean price of $0.42 per kilogram and average application cost of $62 per hectare indicated that fungicide applications were only profitable in 14% of the trial site-years. Insecticide alone and fungicide + insecticide was profitable in 39% and 45% of site-years, respectively. Effect of fungicide class on yield was inconsistent. Our results indicate that although yield increases can occur with foliar fungicide and/or insecticide treatments, current market prices and application costs may limit profitability when disease and/or insect pressure is low. Accepted for publication 22 September 2016.

scholarly journals Skandinavijos investicijų vaidmuo Latvijos žiniasklaidos reintegracijoje į Šiaurės ir Vidurio Europos žiniasklaidos modelį

2008 ◽  
Vol 47 ◽  
pp. 37-43
Author(s):  
Ainārs Dimants
Keyword(s):  
Social History ◽  
Point Of View ◽  
Media Ownership ◽  
North Central ◽  
Central European ◽  
The North ◽  
Media System ◽  
History Of ◽  
The Impact

Straipsnio tikslas – trumpai apžvelgti Latvijos žiniasklaidos privatizacijos ir koncentracijos procesus, sąlygotus užsienio investicijų. Straipsnyje nagrinėjama Skandinavijos, daugiausia Švedijos, kapitalo įtaka redakciniam autonomiškumui, naujų redakcinių instrumentų įdiegimui, siekiant žurnalistikos kokybės ir profesionalumo, o taip pat tokioms žurnalistikos struktūroms, kaip: profesinės sąjungos, žurnalistų rengimas ir mokymas bei žiniasklaidos tyrimai.Straipsnyje teigiama, jog pastarųjų metų Latvijos žiniasklaidos raidą atitinka Šiaurės/Vidurio Europos arba demokratinis-korporacinis žiniasklaidos sistemos modelis, suformuluotas mokslininkų Daniel C. Hallin ir Paolo Mancini trijų žiniasklaidos modelių ir politikos koncepcijoje.The role of Scandinavian investments for the re-integration of Latvian media in the North/Central European model of media systemAinārs Dimants SummaryThe aim of the paper is to give a brief overview about the development and concentration of Latvian media ownership since privatization, from the point of view of the impact of foreign investment. The paper examines the impact of Scandinavian, mainly Swedish, capital on editorial autonomy, on establishing editorial instruments to increase the quality and professionalism of journalism as well as on journalistic infrastructures such as professional unions, training and education and media research.The paper suggests that the North/Central European or Democratic Corporatist Model of media system described by Daniel C. Hallin and Paolo Mancini in their concept of three models of media and politics corresponds to the Latvian media development in the present and in the past.Key words: Latvian media system, models of media system, social history, history of communication, transparency of media ownership, investments, editorial autonomy, journalistic cultures, journalistic infrastructures, professional standards of journalism

scholarly journals FEEDING HABITS OF Paralonchurus brasiliensis (PERCIFORMES: SCIAENIDAE) FROM SOUTH OF BRAZIL

2021 ◽  
Vol 26 (3) ◽  
pp. 335-344
Author(s):  
Mario Cesar Sedrez ◽  
Germano Henrique Costa Barrilli ◽  
Evelise Nunes Fragoso de Moura ◽  
João Pedro Barreiros ◽  
Joaquim Olinto Branco ◽  
...  
Keyword(s):  
Feeding Habits ◽  
Target Species ◽  
North Central ◽  
The North ◽  
Important Prey ◽  
Carnivorous Species ◽  
Xiphopenaeus Kroyeri ◽  
South Of Brazil ◽  
Trophic Webs ◽  
The Impact

Shrimp trawling directly impacts target species and non-target species, altering micro-habitats and marine trophic webs. Thus, the objective of the present research was to analyze the feeding habits of Paralonchurus brasiliensis as a tool to evaluate the impact of trawling on the food chains in marine environments, in the South Atlantic of Brazil. One thousand and nineteen stomachs of P. brasiliensis were dissected after being captured as bycatch of shrimp Xiphopenaeus kroyeri, in Penha, on the north central coast of Santa Catarina, Brazil. The number of stomachs was enough to describe the feeding habits of P. brasiliensis, characterizing it as a carnivorous species and predominantly invertivorous. They also revealed that this species has a diversified and constant diet, with greater consumption of polychaetes, crustaceans, and ofiuroides, among other components of the macrobentos, all closely related to the sediment. It was also found that the target species X. kroyeri is not an important prey in the diet of P. brasiliensis, despite occupying the same habitat. According to the present study, P. brasiliensis can be characterized as a demersal-benthic species, predator, opportunistic and broad trophic spectrum. This work contributes to the understanding of trophic chains of the coastal ecosystems, using the P. brasiliensis as a model.

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