scholarly journals Cloud-to-Ground Lightning Distribution and Its Relationship with Orography and Anthropogenic Emissions in the Po Valley

2014 ◽  
Vol 53 (12) ◽  
pp. 2651-2670 ◽  
Author(s):  
Laura Feudale ◽  
Agostino Manzato

AbstractThe main object of this work is to study the lightning climatology in the Po Valley in Italy and how it varies in time (interannual, annual, weekly, and daily time scales) and space (sea coast, plains, and mountain areas) and how that is related to topographic characteristics and anthropogenic emissions. Cloud-to-ground (CG) lightning in the target area is analyzed for 18 yr of data (about 7 million records). It is found that the Julian Prealps of the Friuli Venezia Giulia region are one of the areas of maximum CG lightning activity across all of Europe. During spring lightning activity is more confined toward the mountainous regions, whereas during summer and even more during autumn the lightning activity involves also the coastal region and the Adriatic Sea. This is due to different triggering mechanisms acting in different topographic zones and during different periods of the year and times of the day. In analogy to previous studies of lightning done in the United States, a weekly cycle is also identified in the area of interest, showing that on Friday the probability of thunderstorms reaches its maximum. After conducting a parallel analysis with monitoring stations of atmospheric particulates (diameter ≤ 10 μm: PM10) and sounding-derived potential instability, the results presented herein seem to support the hypothesis that the weekly cycle in the thunderstorm activity may be due to anthropogenic emissions.

2018 ◽  
Vol 5 (1) ◽  
pp. 120-127
Author(s):  
Inna Chervinska ◽  
Andrii Chervinskyi

The article describes the factors and indicators of sustainable development of mountain areas. The authors analyse the experience of foreign countries in the educational and socio-cultural activities of the inhabitants of the mountains, determine the prospects for its implementation in the mountainous regions of the Ukrainian Carpathians. The researches determine the ways and prospects of development of mountain territories of the Ukrainian Carpathians compare foreign experience of some European countries and the United States on sustainable development. The purpose of the article is based on studying the experience of mountainous countries, identifying the leading factors influencing their sustainable development and revealing the prospects for their implementation in the mountainous regions of the Ukrainian Carpathians. In accordance with the purpose of the study, features of mountain areas were outlined, the factors that determine the specifics of their educational, ecological, economic and socio-cultural development are described. The authors analysed international experience of managing the development of mountain areas in order to determine the possibilities of its use in national practice


2013 ◽  
Vol 13 (20) ◽  
pp. 10461-10482 ◽  
Author(s):  
J. R. Brook ◽  
P. A. Makar ◽  
D. M. L. Sills ◽  
K. L. Hayden ◽  
R. McLaren

Abstract. This paper serves as an overview and discusses the main findings from the Border Air Quality and Meteorology Study (BAQS-Met) in southwestern Ontario in 2007. This region is dominated by the Great Lakes, shares borders with the United States and consistently experiences the highest ozone (O3) and fine particulate matter concentrations in Canada. The purpose of BAQS-Met was to improve our understanding of how lake-driven meteorology impacts air quality in the region, and to improve models used for forecasting and policy scenarios. Results show that lake breeze occurrence frequencies and inland penetration distances were significantly greater than realized in the past. Due to their effect on local meteorology, the lakes were found to enhance secondary O3 and aerosol formation such that local anthropogenic emissions have their impact closer to the populated source areas than would otherwise occur in the absence of the lakes. Substantial spatial heterogeneity in O3 was observed with local peaks typically 30 ppb above the regional values. Sulfate and secondary organic aerosol (SOA) enhancements were also linked to local emissions being transported in the lake breeze circulations. This study included the first detailed evaluation of regional applications of a high-resolution (2.5 km grid) air quality model in the Great Lakes region. The model showed that maxima in secondary pollutants occur in areas of convergence, in localized updrafts and in distinct pockets over the lake surfaces. These effects are caused by lake circulations interacting with the synoptic flow, with each other or with circulations induced by urban heat islands. Biogenic and anthropogenic emissions were both shown to play a role in the formation of SOA in the region. Detailed particle measurements and multivariate receptor models reveal that while individual particles are internally mixed, they often exist within more complex external mixtures. This makes it difficult to predict aerosol optical properties and further highlights the challenges facing aerosol modelling. The BAQS-Met study has led to a better understanding of the value of high-resolution (2.5 km) modelling for air quality and meteorological predictions and has led to several model improvements.


2014 ◽  
Vol 29 (spe) ◽  
pp. 31-40 ◽  
Author(s):  
Ana Paula Paes dos Santos ◽  
José Ricardo Santos de Souza ◽  
Everaldo Barreiros de Souza ◽  
Alexandre de Melo Casseb do Carmo ◽  
Wanda Maria do Nascimento Ribeiro

Operational records of power outages of the electric energy distribution systems in eastern Amazonia presented a large number of events attributed to lightning strikes, during the 2006 to 2009 period. The regional electricity concessionary data were compared to actual lightning observations made by SIPAM's LDN system, over two areas where operational sub systems of transmission lines are installed. Statistical relations were drawn between the monthly lightning occurrence density and the number of power outages of the electric systems for both areas studied. The results showed that, although with some delays between these variables peaks, the number of power disruptions has a tendency to follow the behavior of the lightning occurrence densities variations. The numerical correlations were positive and may be useful to the transmission lines maintenance crews at least for the Belém-Castanhal electricity distribution sub system. Evidence was found, that the SST's over certain areas of the Pacific and Atlantic Oceans, influence convection over the area of interest, and may help to prognosticate the periods of intense electric storms, requiring repair readiness for the regional electric systems.


2021 ◽  
Author(s):  
Kang Sun ◽  
Lingbo Li ◽  
Shruti Jagini ◽  
Dan Li

Abstract. The evolving nature of the COVID-19 pandemic necessitates timely estimates of the resultant perturbations to anthropogenic emissions. Here we present a novel framework based on the relationships between observed column abundance and wind speed to rapidly estimate air basin-scale NOx emission rate and apply it at the Po Valley in Italy using OMI and TROPOMI NO2 tropospheric column observations. The NOx chemical lifetime is retrieved together with the emission rate and found to be 15–20 h in winter and 5–6 h in summer. A statistical model is trained using the estimated emission rates before the pandemic to predict the trajectory without COVID-19. Compared with this business-as-usual trajectory, the real 2020 emission rates show two distinctive drops in March (−41 %) and November (−35 %) that correspond to tightened COVID-19 control measures. The temporal variation of pandemic-induced NOx emission changes qualitatively agree with Google and Apple mobility indicators. The overall net NOx emission reduction in 2020 due to the COVID-19 pandemic is estimated to be 21 %.


2020 ◽  
Vol 20 (21) ◽  
pp. 13379-13397
Author(s):  
Pengguo Zhao ◽  
Zhanqing Li ◽  
Hui Xiao ◽  
Fang Wu ◽  
Youtong Zheng ◽  
...  

Abstract. The joint effects of aerosol, thermodynamic, and cloud-related factors on cloud-to-ground lightning in Sichuan were investigated by a comprehensive analysis of ground-based measurements made from 2005 to 2017 in combination with reanalysis data. Data include aerosol optical depth, cloud-to-ground (CG) lightning density, convective available potential energy (CAPE), mid-level relative humidity, lower- to mid-tropospheric vertical wind shear, cloud-base height, total column liquid water (TCLW), and total column ice water (TCIW). Results show that CG lightning density and aerosols are positively correlated in the plateau region and negatively correlated in the basin region. Sulfate aerosols are found to be more strongly associated with lightning than total aerosols, so this study focuses on the role of sulfate aerosols in lightning activity. In the plateau region, the lower aerosol concentration stimulates lightning activity through microphysical effects. Increasing the aerosol loading decreases the cloud droplet size, reducing the cloud droplet collision–coalescence efficiency and inhibiting the warm-rain process. More small cloud droplets are transported above the freezing level to participate in the freezing process, forming more ice particles and releasing more latent heat during the freezing process. Thus, an increase in the aerosol loading increases CAPE, TCLW, and TCIW, stimulating CG lightning in the plateau region. In the basin region, by contrast, the higher concentration of aerosols inhibits lightning activity through the radiative effect. An increase in the aerosol loading reduces the amount of solar radiation reaching the ground, thereby lowering the CAPE. The intensity of convection decreases, resulting in less supercooled water being transported to the freezing level and fewer ice particles forming, thereby increasing the total liquid water content. Thus, an increase in the aerosol loading suppresses the intensity of convective activity and CG lightning in the basin region.


2018 ◽  
Vol 3 (2) ◽  
pp. 15-26
Author(s):  
Wes Quattrone ◽  
Melissa Callaham ◽  
Stephen Brown ◽  
Tatiana Lin ◽  
Jamie Pina

Background: Over the last decade, the number of health impact assessments (HIAs) conducted has increased. The information contained in these studies provides valuable guidance for stakeholders in many professional fields and industries, also known as sectors. However, a growing body of evidence suggests that practitioners across sectors have unmet information needs and are facing challenges accessing and using information. Methods: The research team conducted a series of focus groups to explore the information needs of practitioners across sectors and to identify challenges they face accessing this information. Participants were stratified by geographic location, sector affiliation, and level of expertise with HIAs. Results: Findings suggest that practitioners from all sectors can benefit from the integration of health-related information, and the information contained in HIAs, into their work. Reported information needs include baseline data, geocoded socio-demographic information, and granular local data. Participants indicated that they obtain information from their professional network, universities sponsoring research, and online resources. Information challenges include lack of data that match the size and the scope of the target area of interest, proprietary or pay-for-access sources, varying terminology for the same concepts across sectors, inadequate resources and HIA expertise for searching, and limited information on the impact of findings of prior completed HIAs. Discussion: Identifying and understanding the information needs of practitioners is essential to maximizing the use of existing and future HIAs. An interactive and comprehensive web-based repository system for HIAs may provide value and assist stakeholders in meeting these needs.


Author(s):  
W E Short II

The chemical and petrochemical industries have decades of experience in specifying metallic piping lined with non-metals as a cost effective alternative to high-priced alloy materials of construction for piping in corrosive service. Early on, application of plastic piping was essentially limited to atmospheric chemical sewage service and to above-ground vents and drains. However, applications and usage of plastic piping continue to increase as engineers become more confident in specifying plastic materials and mechanical contractors gain experience with their installation. Non-metallic materials are being developed that are not only corrosion resistant but also have increasingly higher pressure and temperature capabilities. Plastic double-containment piping has experienced tremendous growth for handling hazards and toxic fluids. In the United States, recent dramatic growth of plastic double-containment piping applications has been, to a large extent, for compliance with the Environmental Protection Agency (EPA) regulations of the 1976 Resource Conservation and Recovery Act (RCRA). Related EPA regulatory efforts were accelerated in 1988 by more stringent amendments to this legislation. Industry in the United States must comply with these EPA regulations by December 1998. Plastic piping and metallic piping lined with non-metals have been covered to some extent by the ASME B31.3 Chemical Plant and Petroleum Refinery Piping Code for several years. The distinctive requirements of non-metallic piping and piping lined with non-metals were incorporated into the 1980 edition as a separate Chapter VII, which is dedicated to this growing area of interest in piping. This paper provides an overview of the present coverage of non-metallic piping lined with non-metals in the ASME B31.3 Chemical Plant and Petroleum Refinery Piping Code (1). Some topics that warrant further investigation are presented as well.


Author(s):  
Eric P. Perramond

The semiarid expanses of northern Mexico have long been a haven for drug trafficking and shipment into the southwestern United States. During the past 3 decades, a more specialized and dedicated drug industry has used the long U.S.-Mexican border to move illicit narcotics. Northern Mexico is not a heavily indigenous zone, and yet some native populations have been adversely affected by this recent industry, and not just a few have taken a role in it. Two states in northern Mexico that still have indigenous peoples are Sonora and Chihuahua. Both of these semiarid states are more sparsely populated than the rest of Mexico, yet both share a long, expansive border with the United States. Thus, neither state has escaped the activities of the drug industry, and some of the major drug cartels are located in this region (figure 8.1), the largest in urban areas such as Ciudad Juarez in the state of Chihuahua and Culiacán in the state of Sinaloa. Although these urban areas are the economic and logistical centers of two large cartels, an aspect frequently ignored in the literature, and certainly in policy circles, is the variety of scales of production in this industry. Aside from these giant cartels, drug cultivation, production, and transportation are also common at lesser scales, and the difficulties and dangers associated with drug production and trafficking extend to these small farmers. Small plots of marijuana (Cannabis sativa) and poppies (Papaver somniferum) dot the northern Mexican landscape, especially in the foothills and high peaks of the Sierra Madre. Most of the poppy production lies further south, in the states of Michoacan, Guerrero, and Oaxaca. Marijuana (Cannabis) is by far the more common of the two illicit crops grown in Mexico, partly because of its longer history of cultivation in the country’s mountainous regions and partly because of its greater ease of integration into agriculture. Poppy fields are a lot harder to hide, both from neighbors and from more interested authorities. Marijuana is also more easily intercropped with more common agricultural crops. Intercropping is the practice of growing two or more crops in the same field or parcel of land, and it is common when farmers need to maximize total output per unit of area (Wilken 1987: 248). I have seen marijuana integrated with corn, bean, squash, sunflower, and tomato plants.


2016 ◽  
Vol 16 (2) ◽  
pp. 607-616 ◽  
Author(s):  
Dieter Roel Poelman ◽  
Wolfgang Schulz ◽  
Gerhard Diendorfer ◽  
Marina Bernardi

Abstract. Cloud-to-ground (CG) lightning data from the European Cooperation for Lightning Detection (EUCLID) network over the period 2006–2014 are explored. Mean CG flash densities vary over the European continent, with the highest density of about 6 km−2 yr−1 found at the intersection of the borders between Austria, Italy and Slovenia. The majority of lightning activity takes place between May and September, accounting for 85 % of the total observed CG activity. Furthermore, the thunderstorm season reaches its highest activity in July, while the diurnal cycle peaks around 15:00 UTC. A difference between CG flashes over land and sea becomes apparent when looking at the peak current estimates. It is found that flashes with higher peak currents occur in greater proportion over sea than over land.


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