Hydrogen soil deposition and atmospheric variations in the boreal zone

This research has been prompted by an interest in the atmospheric processes of hydrogen. The sources and sinks of hydrogen are important to know, particularly if hydrogen becomes more common as a replacement for fossil fuel in combustion. Hydrogen deposition velocities (vd) were estimated by applying chamber measurements, a radon tracer method and a two-dimensional model. These three approaches were compared with each other to discover the factors affecting the soil uptake rate. A static-closed chamber technique was introduced to determine the hydrogen deposition velocity values in an urban park in Helsinki, and at a rural site at Loppi. A three-day chamber campaign to carry out soil uptake estimation was held at a remote site at Pallas in 2007 and 2008. The atmospheric mixing ratio of molecular hydrogen has also been measured by a continuous method in Helsinki in 2007 - 2008 and at Pallas from 2006 onwards. The mean vd values measured in the chamber experiments in Helsinki and Loppi were between 0.0 and 0.7 mm s-1. The ranges of the results with the radon tracer method and the two-dimensional model were 0.13 - 0.93 mm s-1 and 0.12 - 0.61 mm s-1, respectively, in Helsinki. The vd values in the three-day campaign at Pallas were 0.06 - 0.52 mm s-1 (chamber) and 0.18 - 0.52 mm s-1 (radon tracer method and two-dimensional model). At Kumpula, the radon tracer method and the chamber measurements produced higher vd values than the two-dimensional model. The results of all three methods were close to each other between November and April, except for the chamber results from January to March, while the soil was frozen. The hydrogen deposition velocity values of all three methods were compared with one-week cumulative rain sums. Precipitation increases the soil moisture, which decreases the soil uptake rate. The measurements made in snow seasons showed that a thick snow layer also hindered gas diffusion, lowering the vd values. The H2 vd values were compared to the snow depth. A decaying exponential fit was obtained as a result. During a prolonged drought in summer 2006, soil moisture values were lower than in other summer months between 2005 and 2008. Such conditions were prevailing in summer 2006 when high chamber vd values were measured. The mixing ratio of molecular hydrogen has a seasonal variation. The lowest atmospheric mixing ratios were found in the late autumn when high deposition velocity values were still being measured. The carbon monoxide (CO) mixing ratio was also measured. Hydrogen and carbon monoxide are highly correlated in an urban environment, due to the emissions originating from traffic. After correction for the soil deposition of H2, the slope was 0.49±0.07 ppb (H2) / ppb (CO). Using the corrected hydrogen-to-carbon-monoxide ratio, the total hydrogen load emitted by Helsinki traffic in 2007 was 261 t (H2) a-1. Hydrogen, methane and carbon monoxide are connected with each other through the atmospheric methane oxidation process, in which formaldehyde is produced as an important intermediate. The photochemical degradation of formaldehyde produces hydrogen and carbon monoxide as end products. Examination of back-trajectories revealed long-range transportation of carbon monoxide and methane. The trajectories can be grouped by applying cluster and source analysis methods. Thus natural and anthropogenic emission sources can be separated by analyzing trajectory clusters.

Slummiparakeista kyläkarnevaaleihin : Kumpulan ja Toukolan imagonmuutos sanomalehdissä 1963-1999

Having to do with residential areas, geographical image research in Finland has concentrated mainly on those areas with a relatively negative image, such as eastern parts of Helsinki. However, Kumpula and Toukola are former working class residential areas whose image nowadays is mainly positive. This research aims at understanding the process through which their image has gradually come to be that way. Theoretical background of the research relies on human geography and it s viewpoints on places, spaces and areas. Areas, in this research, are understood to be founded on discursive processes that form meanings in societies. This approach is useful because it provides a way to research newspapers and to see how they affect the society. In addition I lean on Sirpa Tani s research on place images to study image and it s formation process. Her point of view covers especially well the effect of media on images and their formation. Articles published in Helsingin Sanomat and Ilta-Sanomat between the years 1963 and 1999 form the data of the research. Methodologically I proceeded by using content analysis to see what kind of topics have been dominating the news feed from Kumpula and Toukola. Content analysis was followed by discourse analysis, which allowed me to focus on the ways of speaking about and representing Kumpula and Toukola. Discourse analysis also reveals whose viewpoint is being represented in media when it comes to publishing news from these parts of the city. It is clearly visible from the results of this research that the image of Kumpula and Toukola has gone through a significant change between 1963 and 1999. In the 1960s discussion in newspapers was dominated by the need for more effective city planning. This meant that Kumpula and Toukola were under a demolition threat in order for the city to built more effectively on those areas. At the same time there was discussion about wooden houses that were built in Kumpula and Toukola right after the second World War. Those houses were in a poor condition, it was even said in the newspapers that people were living in slum-like conditions in them. By the 1980s the image of Kumpula and Toukola gradually started to change. At this time gentrification process was affecting the areas and well-educated working force moved to Kumpula and Toukola. Already in the beginning of 1990s the image of the areas was highly positive. Throughout this decade newspapers published news on Kumpula and Toukola that commented favorably on the atmosphere and the feeling of togetherness among the residents. In addition Kumpula village carnivals, that were first held in 1991, brought a lot of positive publicity to the areas. This research has revelead that especially the active participationg of the residents to promote joint causes has positively affected the image of Kumpula and Toukola. Since the 1960s fighting for the preservation of the areas has provided a reason for a stronger feeling of communality and identifying in the community. This feeling of togetherness in a community has carried all the way to the 1990s, when the areas, having been affected by gentrification, could make good use of the positive image in order to promote joint causes. Keywords: Image, reputation, newspapers, discursive practices

Semi-supervised learning of WLAN radio maps

In this thesis a manifold learning method is applied to the problem of WLAN positioning and automatic radio map creation. Due to the nature of WLAN signal strength measurements, a signal map created from raw measurements results in non-linear distance relations between measurement points. These signal strength vectors reside in a high-dimensioned coordinate system. With the help of the so called Isomap-algorithm the dimensionality of this map can be reduced, and thus more easily processed. By embedding position-labeled strategic key points, we can automatically adjust the mapping to match the surveyed environment. The environment is thus learned in a semi-supervised way; gathering training points and embedding them in a two-dimensional manifold gives us a rough mapping of the measured environment. After a calibration phase, where the labeled key points in the training data are used to associate coordinates in the manifold representation with geographical locations, we can perform positioning using the adjusted map. This can be achieved through a traditional supervised learning process, which in our case is a simple nearest neighbors matching of a sampled signal strength vector. We deployed this system in two locations in the Kumpula campus in Helsinki, Finland. Results indicate that positioning based on the learned radio map can achieve good accuracy, especially in hallways or other areas in the environment where the WLAN signal is constrained by obstacles such as walls.

Using a botanic garden collection to test a bioclimatic vegetation scheme

Vegetation maps and bioclimatic zone classifications communicate the vegetation of an area and are used to explain how the environment regulates the occurrence of plants on large scales. Many practises and methods for dividing the world’s vegetation into smaller entities have been presented. Climatic parameters, floristic characteristics, or edaphic features have been relied upon as decisive factors, and plant species have been used as indicators for vegetation types or zones. Systems depicting vegetation patterns that mainly reflect climatic variation are termed ‘bioclimatic’ vegetation maps. Based on these it has been judged logical to deduce that plants moved between corresponding bioclimatic areas should thrive in the target location, whereas plants moved from a different zone should languish. This principle is routinely applied in forestry and horticulture but actual tests of the validity of bioclimatic maps in this sense seem scanty. In this study I tested the Finnish bioclimatic vegetation zone system (BZS). Relying on the plant collection of Helsinki University Botanic Garden’s Kumpula collection, which according to the BZS is situated at the northern limit of the hemiboreal zone, I aimed to test how the plants’ survival depends on their provenance. My expectation was that plants from the hemiboreal or southern boreal zones should do best in Kumpula, whereas plants from more southern and more northern zones should show progressively lower survival probabilities. I estimated probability of survival using collection database information of plant accessions of known wild origin grown in Kumpula since the mid 1990s, and logistic regression models. The total number of accessions I included in the analyses was 494. Because of problems with some accessions I chose to separately analyse a subset of the complete data, which included 379 accessions. I also analysed different growth forms separately in order to identify differences in probability of survival due to different life strategies. In most analyses accessions of temperate and hemiarctic origin showed lower survival probability than those originating from any of the boreal subzones, which among them exhibited rather evenly high probabilities. Exceptionally mild and wet winters during the study period may have killed off hemiarctic plants. Some winters may have been too harsh for temperate accessions. Trees behaved differently: they showed an almost steadily increasing survival probability from temperate to northern boreal origins. Various factors that could not be controlled for may have affected the results, some of which were difficult to interpret. This was the case in particular with herbs, for which the reliability of the analysis suffered because of difficulties in managing their curatorial data. In all, the results gave some support to the BZS, and especially its hierarchical zonation. However, I question the validity of the formulation of the hypothesis I tested since it may not be entirely justified by the BZS, which was designed for intercontinental comparison of vegetation zones, but not specifically for transcontinental provenance trials. I conclude that botanic gardens should pay due attention to information management and curational practices to ensure the widest possible applicability of their plant collections.

Onnellisten kylät : Vertaileva tapaustutkimus Kumpulan ja Sundsbergin asukkaiden subjektiivisesta hyvinvoinnista sekä onnellisuuden rakentumisesta

The aim of this masters thesis was to examine subjective wellbeing and personal happiness. Empirical study of happiness is part of broader wellbeing reseach and is based on an idea that the best experts of personal wellbeing are the individuals themselves. In addition to perceptions of personal happiness, the aim was also to acquire knowledge about personal values and components personal happiness is based on. In this study, moving into certain community and the charesteristics of neigbourhood contributing happiness, were defined to represent these values. The object was, through comparative casestudy, to obtain knowledge about subjective wellbeing of the inviduals in two different residental areas inside metropolitan area of Helsinki. In comparative case study the intention usually is that the examined units represent spesific "cases" from something broader and therefore the results can be somehow generalized. Consequently the chosen cases in this study were selected due to their image of "urban village" and thus the juxtapositioning was constructed between secluded post-suburban village and more heterogeneous urban village better attached to excisting urban structure. The researh questins were formed as follows: Are there any differencies between the areas regarding the components personal happines is based on? Are there any differencies between the areas regarding the level of residents subjective wellbeing? Based on the residents assesments, what are the most important charesteristics of neigbourhood contributing personal happiness? The data used in order to gain aswers to these questions was obtained from internet-based survey questionnaire. Based on the data residents of post-suburban village Sundsberg seem to share highly family oriented set of values and actualizing these values is ensured with high income, wealth and secure work situation. Insteadt in Kumpula the components of happiness seem place more towards learning and personal developement, interesting leisure and hobbies and specially having an influence regarding communal decisions. Conserning subjective wellbeing of residents there can be seen some differencies as well. Personal life is experienced a bit more happier in Sundsberg than in Kumpula. People are more satified with their personal health and job satisfaction in Sundsberg and additionally feelings of loneliness, inadequancy and frustration are bit more common in Kumpula. Regarding the charesteristics of neigbourhood contributing happiness data suggests that key charesteristics of area are peacefulness and safely, good location and connections and proximity of parks and recreational areas. These charesteristics were concidered highly significant in both areas but they were experienced to actualize better in Kumpula. In addition to these components the residents in Kumpula were overall more satisfied with various charecteristics contiburing happiness in their residental area. Besides these attributes mentioned above residents in Kumpula emphasize also some "softer" elements connecting into social, functional and communal side of area. From Sundsberg point of view residental area best contributing happiness is child friendly and safe community based on likeminded people who share the same sosioeconomical situation. The results of this study can be linked back into the society and metropolitan area, which they were chosen from as a cases to be studied. The results can thereby be seen as an example of differentation of conditions of personal happiness between certain population segments. It is possible to detect an spatial dimetion to this process as well and thereby the results suggests that regional segmentation affects between high-ranking residental areas as well. Thereby the results of this reseach contributes to the debate on innovative, diverse and dynamic urban area and as well cohesion of metropolitan area and the society in whole.

Valtatien 13 parantaminen välillä Lappeenranta–Nuijamaa : Yleissuunnitelma

Valtatien 13 osuus Lappeenrannasta Nuijamaalle kuuluu Euroopan komission päättämään Suomen kattavaan liikenneverkkoon TEN-T. Tieosuus on maan toiseksi tärkein kansainvälisen liikenteen yhteys kuljetuksille ja henkilöliikenteelle. Valtatie 13 kulkee maan poikki länsirannikolta Kokkolasta Lappeenrantaan ja siitä edelleen Nuijamaan rajanylityspaikan kautta Venäjän puolelle Viipuriin. Valtatie 13 palvelee osaltaan myös paikallista liikkumista Nuijamaan kylätaajaman ja Lappeenrannan välillä. Erityisesti Mustolan alueelle ja myös osittain Nuijamaan raja-aseman läheisyyteen suunnitellut ja jo osittain toteutuneet maankäytön kaupalliset palvelut lisäävät voimakkaasti kasvaessaan myös seudullista liikennettä suunnitteluosuudella. Nuijamaan raja-asema on ollut Suomen itärajan toiseksi vilkkain tieliikenteen rajanylityspaikka. Rajanylityspaikan kautta kulki vuonna 2015 noin miljoona ajoneuvoa ja 2,4 miljoonaa matkustajaa. Venäjän ja Suomen valtioiden välisen liikenteen kasvu on ollut voimakkainta Kaakkois-Suomessa ja sille on edelleen perusteltuja kasvuodotuksia, vaikka viime aikoina liikenne on merkittävästi vähentynyt. Myös tavaraliikenteellä on potentiaalia lisääntyä viimeaikaisesta. Suunnittelualueeseen kuuluu valtatien 13 (16,6 km) lisäksi valtatien 6 länsipuolinen valtatien 13 jatke Karjalantie (mt 3821) (1,2 km). Yleissuunnitelmassa on selvitetty valtatien 13 puutteet ja ongelmat, palvelutasotavoitteet, valtatien 13 ja muiden väylien periaateratkaisut tilantarpeineen, suhde ympäröivään maankäyttöön, vaikutukset sekä mahdollisuudet vaiheittain toteuttamiseksi. Päätavoitteena on ollut selvittää valtatien 13 ja muiden väylien kehittämisen periaatteet niin, että palvelutasopuutteet saadaan poistettua ja valtatie 13 vastaa sille asetettuja vaatimuksia liikenteen sujuvuuden ja turvallisuuden kannalta. Osana suunnitelmaa on esitetty toimenpiteet meluhaittojen torjumiseksi ja ympäristövaikutusten lieventämiseksi. Valtatie 13 parannetaan nykyisellä paikallaan korkealuokkaiseksi nelikaistaiseksi valtatieksi tarvittavine tie-, katu- ja liittymäjärjestelyineen. Vastakkaiset ajosuunnat on erotettu toisistaan rakenteellisesti ja kaikki valtatien liittymät ovat eritasoliittymiä.

Seasonal surface urban energy balance and wintertime stability simulated using three land-surface models in the high-latitude city Helsinki

The performance of three urban land surface models, run in offline mode, with their default external parameters, is evaluated for two distinctly different sites in Helsinki: Torni and Kumpula. The former is a dense city centre site with 22% vegetation, while the latter is a suburban site with over 50% vegetation. At both locations the models are compared against sensible and latent heat fluxes measured using the eddy covariance technique, along with snow depth observations. The cold climate experienced by the city causes strong seasonal variations that include snow cover and stable atmospheric conditions. Most of the time the three models are able to account for the differences between the study areas as well as the seasonal and diurnal variability of the energy balance components. However, the performances are not systematic across the modelled components, season and surface type. The net all-wave radiation is well simulated, with the greatest uncertainties related to snowmelt timing, when the fraction of snow cover has a key role, particularly in determining the surface albedo. For the turbulent fluxes, more variation between the models is seen which can partly be explained by the different methods in their calculation and partly by surface parameter values. For the sensible heat flux, simulation of wintertime values was the main problem, which also leads to issues in predicting near-surface stabilities particularly at the dense city centre site. All models have the most difficulties in simulating latent heat flux. This study particularly emphasizes that improvements are needed in the parameterization of anthropogenic heat flux and thermal parameters in winter, snow cover in spring and evapotranspiration in order to improve the surface energy balance modelling in cold climate cities.

Spatial and temporal patterns of greenness on the Yamal Peninsula, Russia: interactions of ecological and social factors affecting the Arctic normalized difference vegetation index

The causes of a greening trend detected in the Arctic using the normalized difference vegetation index (NDVI) are still poorly understood. Changes in NDVI are a result of multiple ecological and social factors that affect tundra net primary productivity. Here we use a 25 year time series of AVHRR-derived NDVI data (AVHRR: advanced very high resolution radiometer), climate analysis, a global geographic information database and ground-based studies to examine the spatial and temporal patterns of vegetation greenness on the Yamal Peninsula, Russia. We assess the effects of climate change, gas-field development, reindeer grazing and permafrost degradation. In contrast to the case for Arctic North America, there has not been a significant trend in summer temperature or NDVI, and much of the pattern of NDVI in this region is due to disturbances. There has been a 37% change in early-summer coastal sea-ice concentration, a 4% increase in summer land temperatures and a 7% change in the average time-integrated NDVI over the length of the satellite observations. Gas-field infrastructure is not currently extensive enough to affect regional NDVI patterns. The effect of reindeer is difficult to quantitatively assess because of the lack of control areas where reindeer are excluded. Many of the greenest landscapes on the Yamal are associated with landslides and drainage networks that have resulted from ongoing rapid permafrost degradation. A warming climate and enhanced winter snow are likely to exacerbate positive feedbacks between climate and permafrost thawing. We present a diagram that summarizes the social and ecological factors that influence Arctic NDVI. The NDVI should be viewed as a powerful monitoring tool that integrates the cumulative effect of a multitude of factors affecting Arctic land-cover change.

Spring snowmelt and midwinter thaw and refreeze north of 60°N based on Seawinds QuikScat 2000-2009

The scatterometer SeaWinds on QuikSCAT provided regular measurements at Ku-band from 1999 to 2009. Although it was designed for ocean applications, it has been frequently used for the assessment of seasonal snowmelt patterns aside from other terrestrial applications such as ice cap monitoring, phenology and urban mapping. This paper discusses general data characteristics of SeaWinds and reviews relevant change detection algorithms. Depending on the complexity of the method, parameters such as long-term noise and multiple event analyses were incorporated. Temporal averaging is a commonly accepted preprocessing step with consideration of diurnal, multi-day or seasonal averages.

Valtatien 13 parantaminen välillä Lappeenranta–Nuijamaa : Hanke-esite

Valtatien 13 osuus Lappeenrannasta Nuijamaalle kuuluu Euroopan komission päättämään Suomen kattavaan liikenneverkkoon TEN-T. Tieosuus on maan toiseksi tärkein kansainvälisen liikenteen yhteys kuljetuksille ja henkilöliikenteelle. Valtatie 13 kulkee maan poikki länsirannikolta Kokkolasta Lappeenrantaan ja siitä edelleen Nuijamaan rajanylityspaikan kautta Venäjän puolelle Viipuriin. Valtatie 13 palvelee osaltaan myös paikallista liikkumista Nuijamaan kylätaajaman ja Lappeenrannan välillä. Erityisesti Mustolan alueelle ja myös osittain Nuijamaan raja-aseman läheisyyteen suunnitellut ja jo osittain toteutuneet maankäytön kaupalliset palvelut lisäävät voimakkaasti kasvaessaan myös seudullista liikennettä suunnitteluosuudella. Nuijamaan raja-asema on ollut Suomen itärajan toiseksi vilkkain tieliikenteen rajanylityspaikka. Rajanylityspaikan kautta kulki vuonna 2015 noin miljoona ajoneuvoa ja 2,4 miljoonaa matkustajaa. Venäjän ja Suomen valtioiden välisen liikenteen kasvu on ollut voimakkainta Kaakkois-Suomessa ja sille on edelleen perusteltuja kasvuodotuksia, vaikka viime aikoina liikenne on merkittävästi vähentynyt. Myös tavaraliikenteellä on potentiaalia lisääntyä viimeaikaisesta. Suunnittelualueeseen kuuluu valtatien 13 (16,6 km) lisäksi valtatien 6 länsipuolinen valtatien 13 jatke Karjalantie (mt 3821) (1,2 km). Yleissuunnitelmassa on selvitetty valtatien 13 puutteet ja ongelmat, palvelutasotavoitteet, valtatien 13 ja muiden väylien periaateratkaisut tilantarpeineen, suhde ympäröivään maankäyttöön, vaikutukset sekä mahdollisuudet vaiheittain toteuttamiseksi. Päätavoitteena on ollut selvittää valtatien 13 ja muiden väylien kehittämisen periaatteet niin, että palvelutasopuutteet saadaan poistettua ja valtatie 13 vastaa sille asetettuja vaatimuksia liikenteen sujuvuuden ja turvallisuuden kannalta. Osana suunnitelmaa on esitetty toimenpiteet meluhaittojen torjumiseksi ja ympäristövaikutusten lieventämiseksi. Valtatie 13 parannetaan nykyisellä paikallaan korkealuokkaiseksi nelikaistaiseksi valtatieksi tarvittavine tie-, katu- ja liittymäjärjestelyineen. Vastakkaiset ajosuunnat on erotettu toisistaan rakenteellisesti ja kaikki valtatien liittymät ovat eritasoliittymiä.