Modeling the growth and regional extent of new particle formation events

As aerosol particles are important for global climate effects, their sources and influence on global aerosol particle concentrations need to be quantified. One of the major aerosol sources in the atmosphere is new particle formation (NPF) of new nanometer sized particles in the atmosphere. The influence on the global aerosol concentration due to NPF events is however not well quantified. The goals of this study is to examine how new particle formation (NPF) events influence the regional particle number size distribution in the air and how this affect the time dependent number size distribution measured at different field sites around the world. The method we used to approach this was to create a one dimensional box model including various aerosol dynamic processes that simulates NPF events during long range transport in the atmosphere. The factors, which influence NPF events and the resulting size distributions that can be studied in this model are: 1. Particle formation rates during NPF events. 2. Wind speed, and 3. Growth of the newly formed particles. In the examination of the effects of the aerosol dynamic processes, coagulation and dry deposition, the analysis showed us the effectiveness of coagulation in removing small particles (< 10 nm diameter) and that dry deposition was also effective in removing the largest particles below 1 µm diameter. During the examination of the effect of formation rates, we could clearly see that the concentration of particles is dependent on the magnitude of the NPF event. If the formation takes place over a smaller geographical area the NPF events, as registered at a downwind site, were consisting of particles of approximately the same size. During the simulations with varying time and place where particles experienced growth during NPF events, the size distribution measured downwind of where the particles were formed showed relatively varying sizes and concentrations, which is difficult to interpret in real situations at a field site where the size distribution is measured. With this model, these situations can be understood and simulated. We have, however, not tried the model against measured data at field sites. In future research one should include quantifying the effects at field sites and continue to investigate in detail the other effects of varying different factors like the wind speed, formation rate and growth rate during NPF events

Spatially varying parameters in observed new particle formation events

Aerosol particles affect the global climate due to its influence on the scattering and absorption of short-wave and long-wave radiation. The extent of the influence of aerosol particles on the climate varies a lot by time and space, and needs to be quantified. One of the most important natural sources of atmospheric particles is new particle formation (NPF). However, the contribution of NPF events on the aerosol concentrations in different regions need to be better quantified before they can be realistically described in climate models. This is of great interest due to the ongoing climate debate. Atmospheric NPF events are typically studied at stationary measurement sites, at which the observed changes in particle number concentration and size can be linked to both temporal and spatial changes in the particle formation and growth parameters, even though the spatial component is often neglected. The goal of this study is to examine how common the spatial variations in particle formation and growth parameters are, and how they affect the observed NPF events. The method used to examine this was to first use an improved version of an existing model to simulate different NPF cases assuming spatially and/or temporally varying input parameters. From these simulations the “fingerprints” for the different parameter variations were identified. Thereafter we analyze 8 years of particle number size distribution data from measurement sites Pallas and Värriö, in Finnish Lapland, and compared the observations of NPF events to the fingerprints of the different variations in cases when the same air mass was observed at both sites. Our results indicate that the beginning of the event is typically time dependent which could be explained by the diurnal evolution of a turbulent boundary layer. The end of the NPF event tends to be more typically dependent on location. In our observations in Northern Scandinavia this could be connected to the air mass arriving from sea to land or over the Scandinavian mountains. These findings indicate that the spatial variations of the particle formation and growth parameters cannot be neglected when analyzing NPF events.Det globala klimatet påverkas av strålningsbalansen i atmosfären. Strålningsbalansen påverkas av ett antal faktorer och bland annat aerosolpartiklar. Hur stor påverkan aerosolpartiklarna har är osäkert och det är något som det forskas mycket om i nuläget. Partiklarna som finns i atmosfären har många olika källor, de kommer från bland annat industriell verksamhet, trafiken, vulkanutbrott men också från så kallade nypartikelbildningshändelser. Under en sådan händelse slås molekyler i luften samman och bildar partiklar som sedan växer i storlek. Detta fenomen är väldigt viktigt eftersom stora delar av alla moln uppstår från dessa partiklar och molnen i sig har stor påverkan på strålningsbalansen. Nypartikelbildning och tillväxten av dessa partiklar sker i olika områden och vid olika tidpunkter. Detta påverkar storleksfördelningen av partiklarna som mäts vid olika fältstationer och denna variation kan göra mätningarna svårtolkade. Målet med denna studie är att ta reda på hur vanligt det är med rumslig variation av bildningen och tillväxten av dessa nyskapade partiklar. Detta gjordes genom att först förbättra en redan existerande modell så denna kunde simulera olika fall av nypartikelbildning där man antagit rumslig eller tidsenlig variation av inmatningen. Med dessa simuleringar identifierades olika ”fingeravtryck” som visade hur inmatningsparametrarna påverkade resultatet av nypartikelbildnings-händelserna. Därefter analyserades 8 år av data från mätstationerna Pallas och Värriö, i Finska Lappland, för att se hur vanligt det var med rumslig variation. Vårt resultat indikerar att början av nypartikelbildningshändelserna är vanligtvis tidsberoende vilket kan förklaras av dygnsrytmen av atmosfärens gränsskikt. Slutet av nypartikelbildningshändelserna har en tendens att vara beroende av position snarare än tid. Denna upptäckt indikerar att man inte kan försumma rumslig variation av bildning och tillväxt av aerosolpartiklar

The new demand-driven post-occupancy evaluation

Copyright 1988, Locke Science Publishing Co., Chicago, IL, All Rights Reserved.Post-Occupancy Evaluation (POE) has become increasingly accepted and influential among client organizations responsible for large building management and construction programs. Managers and administrators look to POE to provide answers to important facilities questions. This increased focus on decision-making has resulted in a number of changes to the way in which POEs are conducted, including changes in the relationship between evaluator and client, the range of issues addressed, and the salience of certain methodological concerns. These issues are considered in light of current uses for POE information and some strategic choices faced by evaluators and clients

Coupling an aerosol box model with one-dimensional flow : a tool for understanding observations of new particle formation events

Field observations of new particle formation and the subsequent particle growth are typically only possible at a fixed measurement location, and hence do not follow the temporal evolution of an air parcel in a Lagrangian sense. Standard analysis for determining formation and growth rates requires that the time-dependent formation rate and growth rate of the particles are spatially invariant; air parcel advection means that the observed temporal evolution of the particle size distribution at a fixed measurement location may not represent the true evolution if there are spatial variations in the formation and growth rates. Here we present a zero-dimensional aerosol box model coupled with one-dimensional atmospheric flow to describe the impact of advection on the evolution of simulated new particle formation events. Wind speed, particle formation rates and growth rates are input parameters that can vary as a function of time and location, using wind speed to connect location to time. The output simulates measurements at a fixed location; formation and growth rates of the particle mode can then be calculated from the simulated observations at a stationary point for different scenarios and be compared with the 'true' input parameters. Hence, we can investigate how spatial variations in the formation and growth rates of new particles would appear in observations of particle number size distributions at a fixed measurement site. We show that the particle size distribution and growth rate at a fixed location is dependent on the formation and growth parameters upwind, even if local conditions do not vary. We also show that different input parameters used may result in very similar simulated measurements. Erroneous interpretation of observations in terms of particle formation and growth rates, and the time span and areal extent of new particle formation, is possible if the spatial effects are not accounted for.Peer reviewe

Costo aeróbico de la energía: concientización sobre el uso racional de energía involucrando a la juventud en un proceso recreativo de generación sustentable

El trabajo presenta un proyecto de desarrollo tecnológico de un dispositivo móvil en el cual doce personas pedaleando simultáneamente generarán la energía eléctrica necesaria para que una banda de música pueda dar su recital. Se calculan los parámetros eléctricos y mecánicos a partir de ensayos y se muestran los esquemas de conexión. El objetivo principal es la concientización y educación de la población en el uso racional de la energía y el desarrollo sustentable a través del esfuerzo físico que representa. Además se presentan los distintos medios utilizados para la difusión y el logro del impacto esperado.This paper presents a project of the development of a technological device, in which twelve people cycling all together can generate electric energy for the performance of a musical band in a concert. Mechanical and electrical parameters are calculated from the results of essays and the connection schematics are shown. The main aim is to educate the population on rational use of energy and sustainability through the physical effort it represents. The different means of communication to provide the correct impact are also presented.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Costo aeróbico de la energía: concientización sobre el uso racional de energía involucrando a la juventud en un proceso recreativo de generación sustentable

El trabajo presenta un proyecto de desarrollo tecnológico de un dispositivo móvil en el cual doce personas pedaleando simultáneamente generarán la energía eléctrica necesaria para que una banda de música pueda dar su recital. Se calculan los parámetros eléctricos y mecánicos a partir de ensayos y se muestran los esquemas de conexión. El objetivo principal es la concientización y educación de la población en el uso racional de la energía y el desarrollo sustentable a través del esfuerzo físico que representa. Además se presentan los distintos medios utilizados para la difusión y el logro del impacto esperado.This paper presents a project of the development of a technological device, in which twelve people cycling all together can generate electric energy for the performance of a musical band in a concert. Mechanical and electrical parameters are calculated from the results of essays and the connection schematics are shown. The main aim is to educate the population on rational use of energy and sustainability through the physical effort it represents. The different means of communication to provide the correct impact are also presented.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

bim management guidelines of the construction process for general contractors

Capability of construction companies to manage the digital interoperability between stakeholders and technicians is fundamental for the success of a work, both for new constructions and renovations. The research outlines a methodological and operational protocol for general contractors and the related supply chains and subcontractors. The Programme contains indications for the development of BIM-based workflows that implement the main activities in building construction, operations and maintenance: off-site and on-site time schedules, site planning and building ergotechnics, accounting, project variances, non-compliance issues, test and commissioning, maintenance planning

Potentialbedömning av marin strömkraft i Finnhamn : Fältmätningar och resultat

På uppdrag av Skärgårdsstiftelsen utfördes mätningar av vattenhastigheten utanför Finnhamn i syfte att undersöka potentialen för att installera och driva ett marint strömkraftverk på platsen. Denna rapport presenterar resultaten från den undersökningen som genomförts med tvärsnittsmätningar och långtidsmätningar av vattenhastigheterna. Resultaten visar på låga vattenhastigheter under mätperioden. Slutsatsen är att platsen inte har tillräckligt stor energipotential för att vara av intresse för utbyggnad av strömkraftverk utifrån den teknik som finns idag.På uppdrag av Skärgårdsstiftelsen i Stockholms län. Kartläggningen finansierad av Zennström Philantropies, Regionala Strukturfondsprogrammet.</p