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35 Uppsatser om Atmospheric advection - Sida 1 av 3
Numerisk modell för global transport av spårämnen i atmosfären
The aim of this project was to develop a numerical model simulating the global transport of air pollution. The model currently used by SMHI, the Swedish Meteorological and Hydrological Institute, was intended to perform such simulations at regional scales. However, the usage of a grid based on longitudes and latitudes makes this model work poorly in global simulations. The problem with this grid is that the nodes are concentrated near the North and South Poles. Due to this characteristic, the Courant, Friedrich and Lewy-condition for numerical stability puts a sharp bound on the timestep length.
Samband mellan luftföroreningar och klimatfaktorer - en statistisk unersökning
That air pollutants of different kind has impact on our climate can hardly haveavoided anyone during the past years environment explosion in the media. But howis it actually with the reverse, i. e. the climate's impact on air pollutants? The aimwith our degree thesis is to try to find out if different weather factors, statisticallyseen, promotes atmospheric pollutants and particles in the air and vice versa.We got access to data on air pollutants and weather factors that was registeredduring year 2007 at Femmanhusets air pollutant and weather station in Gothenburg.In order to do a statistical investigation of these data, and to be able to analyze if itoccurs relations of various kind, we used the statistics program SPSS.
Musikens oanade effekter - En studie om musik i dagligvarubutiker
The retail industry is complex and when it comes to the in-store environment conventional marketing tools seldom find their way. The impacts of in-store atmospherics on customers and the psychological impact the store environment has on their decision-making are rather remarkable. An in-store atmospheric that often is used in order to affect customers is music, in fact it is one of the in-store elements that has been investigated more carefully. Nevertheless, in spite several studies on music and its impact as an in-store atmospheric on customers, it is not yet obvious what applies. To bring some clarity on the subject this study is aspiring to explain what applies when it comes to playing music in grocery stores.
Design and Analysis of an All-optical Free-space Communication Link
Free Space Optics (FSO) has received a great deal of attention lately both in the military and civilian information society due to its potentially high capacity, rapid deployment, portability and high security from deception and jamming. The main issue is that severe weather can have a detrimental impact on the performance, which may result in an inadequate availability. This report contains a feasibility study for an all-optical free-space link intended for short-range communication (200-500 m). Laboratory tests have been performed to evaluate the link design. Field tests were made to investigate availability and error performance under the influence of different weather conditions.
En analys av nattliga koldioxidflöden i en boreal barrskog avseende spatial och temporal variation
Carbon dioxide in the atmosphere contributes to the greenhouse effect, which is essential tolife on our planet. Furthermore, it plays an important part of the photosynthesis andrespiration of the world?s organisms. Since the start of the industrial revolution the amount ofcarbon dioxide in the atmosphere has increased exponentially. The main source is theextensive burning of fossil fuels.
Strömningen i och över en skog : utvärdering av en 'mixing-layer' hypotes
A new theory for predicting the windprofile over a canopy has been evaluated. The theory was first presented by Harman and Finnigan (2007). The theory relies on the forming of a mixing-layer above the canopy, due to different mean wind in and above the canopy. Characteristics from both mixing-layer and Monin Obukhov similarity theory have been used to develop the governingequations that give the wind profile. The theory has been used to calculate wind profiles for sixdifferent atmospheric stabilities.
Årstidsdynamik för kvicksilver i ett sövattensediment :
The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment.
The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake.
Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.
Transporttider för vatten i närområdet till en vattentäkt : spårämnesförsök i en isälvsavlagring
When establishing a groundwater protection area it is of great interest to be able to estimate the transit time of the groundwater from different places of the aquifer to the withdrawal well. These estimates can be uncertain due to heterogeneities in the aquifer. As a part of the work to develop methods for a more certain delineation of protection areas, a tracer test was performed in an esker located 25 kilometres NW of the town Uppsala.The purpose of this master thesis was to perform, describe and evaluate the tracer test. Travel times from the tracer test should then enable comparison against stochastic simulated travel times of the groundwater in the area.Three dyes (rhodamine WT, uranine and naphtionate) and a salt (NaBr) were used in the tracer test. The tracers were injected in four different wells located 25 meters from a pumping well.
El nino- Southern ocsillation och de tropiska cyklonerna i Stilla havet
ReferatDe tropiska cyklonerna har både skrämt och fascinerat människor genomtiderna och det pågår en hel del forskning kring dem. I detta arbete studeras omEl niño?Southern ocsillation påerkar antalet, intensiteten eller livslägden pådetropiska cyklonerna i Stilla havet. Till detta anväds temperaturdata frå bojarsom den amerikanska väertjästen National Oceanic and AtmosphericAdministration placerat ut i Stilla havet och insamlad information kring detropiska cyklonerna. Studien baseras pådata frå en 15ås period under åen1995 till 2009.Studien visar bland annat att antalet tropiska cykloner påerkas relativt mycketav de olika faserna i El niñ? Southern oscillation.
Städer och planetära gränser : En utvärdering av Stockholms ochNorra Djurgårdsstadens påverkan påde planetära processerna
The concept of planetary boundaries was introduced in the year 2009 by a group ofresearchers led by Johan Rockström and Will Steffen. The group presented a draft of thelimits of the planet regarding nine Earth System processes concerning climate change, oceanacidification, stratospheric ozone depletion, atmospheric aerosol loading, interference with Pand N cycles, global freshwater use, land-system change, rate of biodiversity loss andchemical pollution. The starting point for the study presented in this report was that asustainable development only can be achieved if humankind stays within the boundaries. It istherefore, based on the ongoing urbanization, relevant to evaluate how cities affect the EarthSystem processes. The aim of the study was to investigate if Stockholm Royal Seaport (NorraDjurgårdsstaden), a district in the northeast of Stockholm with a clear environmental profile,affects the Earth System processes less than Stockholm in general does.
Storjuktan ? Rekonstruktion av ett sekels kvicksilverbelastning. : En undersökning av kvicksilverkoncentrationer i daterat bottensediment.
The aim of this study was to examine the current and historic mercury(Hg) load of the lake Storjuktan due to its recent exposure to a local potential source of Hg in form of the Sulphide mine Blaikengruvan(2006) and an earlier potential sources of Hg-load, the damming of the lake(1960s). Sediments were extracted using a HTH-sampler, freeze-dried, and analyzed for tot-Hg, LOI and activity of 210Pb and compared to samples extracted prior to the opening of the mine(2006). Constant initial concentration (CIC)-dating model was used for dating the samples. Low levels of Hg (100ng/g) were found throughout the lakes sediment. The highest levels of Hg(220ng/g) was detected at a depth of 4-5cm dating back to the mid 1970:s, suggesting that increased levels of atmospheric Hg rather than damming of the lake has caused the increase of Hg.
Vattennivåförändring kring Gamla Uppsala och dess påverkan på människan
ReferatDe tropiska cyklonerna har både skrämt och fascinerat människor genomtiderna och det pågår en hel del forskning kring dem. I detta arbete studeras omEl niño?Southern ocsillation påerkar antalet, intensiteten eller livslägden pådetropiska cyklonerna i Stilla havet. Till detta anväds temperaturdata frå bojarsom den amerikanska väertjästen National Oceanic and AtmosphericAdministration placerat ut i Stilla havet och insamlad information kring detropiska cyklonerna. Studien baseras pådata frå en 15ås period under åen1995 till 2009.Studien visar bland annat att antalet tropiska cykloner påerkas relativt mycketav de olika faserna i El niñ? Southern oscillation.
Undersökning av sambandet mellan strålningstemperatur och NDVI i Sahel
Several studies have analysed the relationship between Normalised DifferenceVegetation Index (NDVI) and radiative surface temperature. A main goal for moststudies have been to find the best method for carrying out land cover classificationsand to study land cover changes, based on a combination between the twoparameters. Since atmospheric components have a significant influence on bothparameters, most applications were based on multi-temporal data. The quality of theindividual values in such a combination is improved, but the biophysical justificationis uncertain. This study presents a different method, based on only the combination ofvalues that have been registered the same day and about the same time of the day.125 daily images of NDVI and 250 images of radiometric temperature were used inorder to analyse the relationship between (1) NDVI and radiative temperature and (2)NDVI and relative temperature difference between early morning and mid-day.Results between NDVI and radiative temperature show a significant negativecorrelation on areas where a distinct growing season develops, and a strong positivcorrelation where vegetation is abscent throghout the season.
ETT MED NATUREN. En ekokritisk studie av naturmotivet hos tre svenska skräckförfattare
Since time immemorial, nature has been conceived of as a female entity. This ancient concept is also a recurring element in contemporary Swedish horror fiction. The purpose of this thesis is to compare the feature of nature in the selected works of Anders Fager, Andreas Marklund and Frida Arwen Rosesund and in what ways these respective depictions rely on a tradition where nature is gendered female. The theoretical starting-point for this comparative study is ecocriticism and its subcategory ecofeminism, which are modes of literary criticism where the role of nature in general, and its female connotations in particular, are appreciated as significant literary features. For executing an analysis that goes beyond what is explicit, the exploration of these three writers? texts also adopts a psychoanalytical perspective.
Dendroklimatologisk analys av lokalklimat vid Grövelsjön i Dalafjällen
Climate on earth is getting warmer, which effects earth?s energy balance and so forth the ocean and atmospheric circulation. In many sub-polar regions on the northern hemisphere changes due to warming of the climate can be observed. Some examples that already have been observed are shifts in tree line, towards higher altitudes and latitudes, increased ablation of Swedish glaciers and melting of the permafrost on the Siberian tundra. In Sweden climate change scenarios tell us that it will become warmer and that a higher amount of precipitation in form of rain will be an effect from this. To study climate changes in Sweden, transition zones are useful in order to observe changes in distribution of species and animal populations.