<p>På grund av världens växande befolkning och urbaniseringen blir problem relaterade till fenomenet urbana värmeöar mer och mer påtagliga. Eftersom urbana parker kan minska påfrestningen skapad av urbana värmeöar kan de vara ett kraftfullt verktyg vid klimatdesign i städer. Temperaturen nära en yta bestäms av energiutbytet mellan ytan och luften ovanför och det är därför nödvändigt att man förstår energibalansen vid markytan för att kunna hantera parkernas mikroklimat. Syftet med det här arbetet var att studera skillnaderna mellan energibalansen för olika ytor i parken och i dess omgivning och att relatera skillnaderna i energibalanserna till temperaturskillnaderna.</p><p>Mätningarna utfördes under tre klara sommardagar i parken Humlegården i centrala Stockholm. Mätutrustningen var monterad på en kärra som flyttades från mätplats till mätplats. Mätplatserna representerade olika typiska ytor i Humlegården och i dess omgivning: en skuggad och en öppen gräsmatta, en öppen och en skuggad grusyta och två asfaltytor, varav en löper i nord-sydlig riktning och en i öst-västlig riktning.</p><p>Energiflödena beräknades med hjälp av data för luft- och yttemperatur, vindhastighet, luftfuktighet och nettostrålning.</p><p>Resultaten visade att den tydligaste skillnaden mellan gräs- och grusytorna i parken var att gräsytorna hade ett större nedåtriktat latent värmeflöde under natten och ett mindre markvärmeflöde under hela dygnet. Den mest distinkta skillnaden mellan de skuggade och öppna ytorna i parken var att de skuggade ytorna hade mindre energiflöden under dagen och att de till skillnad från de andra ytorna hade ett nedåtriktat sensibelt värmeflöde under dagen. Den största skillnaden mellan ytorna i och utanför parken var att asfaltytorna hade ett större uppåtriktat sensibelt värmeflöde och markvärmeflöde under natten.</p><p>Under natten var den svalaste mätplasten den öppna gräsmattan, vilken också var den enda mätplasten med ett nedåtriktat sensibelt värmeflöde under natten. Jämfört med de andra ickeskuggade mätplasterna hade den öppna gräsmattan ett mindre markvärmeflöde. Varmaste mätplasterna under natten var asfaltytorna som även hade ett större uppåtriktat sensibelt och markvärmeflöde än de andra ytorna. Under dagen var de skuggade ytorna i parken de svalaste platserna. De var de enda ytorna med ett nedåtriktat sensibelt värmeflöde och nettostrålningen vid ytan var mindre än för de flesta andra mätplatser.</p> / <p>The world’s growing population and the increasing urbanization has made problems related to the urban heat island phenomenon to become more pronounced and since urban parks reduce the stress produced by the urban heat island they can be powerful tools in urban climate design. The temperature near the surface in a park is determined by the energy exchanges between the surface and the air above and it is therefore necessary to understand the surface energy balance of parks to intelligently manage their thermal microclimate. The objectives of this work were to study how the energy balances differ between different surfaces inside parks and in their built-up surroundings and to relate the surface energy balances to temperature differences.</p><p>Measurements were conducted during three clear summer days in the park Humlegården located in central Stockholm. The measuring instruments were mounted on a cart, which was transported from observation site to observation site. The observation sites represented typical surfaces found in an urban park and its surroundings: one shaded and one open grass surface, one open and one shaded gravel surface and two paved surfaces representing streets running in the north-south and east-west directions respectively. The energy fluxes were calculated using air and surface temperatures, wind speed, air humidity and net radiation data.</p><p>The most pronounced differences between the shaded and open surfaces in the park was that the shaded surfaces in general had smaller energy fluxes during daytime and that they had a downward directed sensible heat flux while the open surfaces had an upward directed sensible heat flux during the day. The most significant difference between the grass and the gravel surfaces in the park was that the grass surfaces had a bigger downward directed latent heat flux during the night and a smaller ground heat flux during both day and night. The largest differences between the surfaces inside the park and those in its built-up vicinities were that the paved surfaces had a larger upward directed sensible and ground heat flux during the night than the other surfaces. During the day the north-south directed paved site had a downward directed ground heat flux that was much larger than the ground heat flux for the other sites.</p><p>The coolest site during the night was the non-shaded grass surface, which was the only site with a downward directed sensible heat flux during the night. Compared to the other nonshaded sites the open grass surface had a much smaller ground heat flux. Warmest sites during the night were the paved surfaces, which had a larger upward directed sensible and ground heat flux than the other surfaces. At the built-up sites the walls also contributed with sensible heat flux, i.e. the total sensible heat flux in the built-up area was larger than what comes from the street surface only. During the day the shaded surfaces in the park were the coolest sites. The shaded surfaces had less net radiation compared to the other non-shaded surfaces and were the only sites that had a downward directed sensible heat flux.</p>

<p>The entry of satellite-derived decadal cloud datasets with homogeneous coverage in time and space enables studies not possible before. This thesis presents two such applications. The first study deals with cloud-aerosol processes and the second with an evaluation of cloud simulations from a regional climate model.</p><p>The first part of the thesis describes the used satellite-derived dataset based on imagery from the Advanced Very High Resolution Radiometer (AVHRR) on the polar orbiting NOAA satellites. A method for cloud retrieval and the compilation of a 1991-2000 Scandinavian cloud climatology are described.</p><p>The second part reveals an intriguing anti-correlation between monthly mean satellite-derived cloudiness and the concentration of the cosmogenetic isotope Beryllium-7 in near-surface aerosol samples for three measurement sites in Sweden. Large-scale transport processes are suggested as the most likely physical mechanism for this behaviour but more complex relations to cloud microphysical processes are not ruled out.</p><p>The final part presents a thorough evaluation of cloud simulations of the SMHI Rossby Centre regional atmospheric model (RCA3). Several model-to-satellite adaptations are applied to avoid artificial biases of results. The study stresses the necessity to account for initial differences between observed and modelled clouds caused by satellite cloud detection limitations. Results show good agreement of modelled and observed cloud amounts while the vertical distribution of clouds appears largely different. RCA3 underestimates medium-level clouds while overestimating low- and high-level clouds. Also, the current use of the Maximum cloud overlap approach in the radiation scheme and an indicated excess of cloud condensate in modelled clouds appear to create excessive cloud optical thicknesses with serious implications for the surface radiation budget.</p><p>Future applications are outlined based on greatly enhanced satellite-derived cloud and radiation budget datasets.</p>

Dendrochronological research on Juniperus polycarpos growing in west and central Iran reveals that the radial growth in this species depends mainly on the amount of precipitation in the more arid regions. When the amount of rain is sufficient, i.e. above 450 mm, the prevailing summer temperature seems to become the limiting factor. Favorable conditions which prevailed during the periods 1685-1695 and 1790-1800 resulted in better width growth, while less favorable conditions which prevailed during the years 1725-1735 and 1855-1865 resulted in narrow rings.

Approved for public release, distribution is unlimited / This thesis investigated the hypothesis that variations in tropical cyclone (TC) activity in the western North Pacific (WNP) may affect the teleconnection between the tropical WNP and North America. The teleconnection patterns of the 500 hPa geopotential height between a base point in the WNP (20 N 115 E) and a domain over North America (30 - 45 N, 70 -90 W) from 1951-2001 were examined. The 25 most active and the 25 least active TC years for two regions with the highest climatological average of TC activity, near the Philippines and Taiwan, respectively, were compared to determine if stronger teleconnection patterns occur during the more active years. For both regions, the correlation pattern is significant during active years and insignificant during inactive years, with the results based on TC activity in the Philippines region showing a larger difference. An analysis of 500 hPa mean winds showed weaker winds in the midlatitudes during active TC years when the teleconnection is stronger, which suggests that the teleconnection may consist mainly of Lau and Weng's (2000) zonally-elongated mode (Mode 1). Further cross correlations of the geopotential height and TC frequency parameters with the tropical eastern and western Pacific sea-surface temperatures (SST's) showed a significant correlation between TC activity and tropical eastern Pacific SST's, but the North America-WNP correlation is unlikely to be a result of a direct influence of SST's on the two regions. / Captain, United States Air Force

Spatial and temporal distribution of precipitation in the Vosges mountain range area Abstract The aim of this work is to study the climatology of atmospheric precipitation in the studied area situated in the Northeastern France. Factors, e.g. the global circulation of the atmosphere, that influence the spatial and temporal distribution of precipitation in the mid-latitudes, especially in Western Europe and in mountainous regions, are discussed from the macro- to micro- scale in the first part. The term "ombric continentality" is clarified and a description of the physical geography of the studied area is performed, e.g. upward and windward asymmetry of Vosges slopes and contrasts between the mountain range and the Upper Rhine Plain. Secondly a demonstration is made that the Vosges mountain range affects, due to its position, the spatio-temporal distribution of precipitation at a regional scale. This is carried out by computing the daily rainfall on 14 meteorological stations out of the period 1951-2011. Three categories of stations were determined according to their annual precipitation repartition: (i) mountain stations with the winter precipitation maximum, (ii) leeward slope stations with two precipitation maxima, i.e. in winter and summer and (iii) leeward stations located in the Upper Rhine Plain East...

The Charles University Faculty of Science KFGG team took part in an intensive research in the area of Kyrgyz glacial lakes. The collecting of records from three meteorological stations in the locations of Kolor (2,700 m above sea level) and Adygine (3,500 and 3,800 meters above sea level) was part of the research. The aim of this thesis was to analyze the homogeneity of climatic data measured in experimental locations using the SNHT method (Standard Normal Homogeneity Test), process the data using general climatological processes, create a classification of circulation types for the area of interest using Jenkinson's and Collinson's method, and finally, to quantify the relationships between individual circulation types and the values of chosen climatic elements. The analysis results are homogenized climatic sets for the Adygine H station (3,800 m above sea level) and a summary of basic statistics and trends of climatic elements in the area. Furthermore, a catalogue of circulation types was created for the period from August 2007 to July 2011, and finally, the relationships between individual circulation types and manifestations of climate elements (air temperature, precipitation and global radiation). The results of this thesis may be used to identify the types connected with bursts of glacial...

La rêverie est pour la peinture une façon de tenter d’échapper avec perversité à la rigueur de l’image. L’agencement des surfaces, les teintes, les effets de matière ne sont que les traces de ses divagations diurnes. Elle trompe celui qui la regarde en apparaissant alanguie et comme endormie. La rêverie de la matière et des surfaces est un détour sur place qui permet d’atteindre ce qui est déjà là comme peut le faire la perversion. L’effronterie s’amuse à sortir de la froide cristallisation de l’image par le jeu des plans qui s’excitent à la surface du tableau. Pour ressentir enfin quelque chose, la peinture est prête à tout : détourner, noyer, feindre la profondeur, s’abandonner, se laisser absorber, quitter la forme et le genre, nier l’autre, etc. Provocation à seulement sentir, l’expérience de la peinture recoupe l’épreuve sensible comme telle et l’incorpore. Elle opère par contagion et non par représentation. Elle rend à la lettre les surfaces sensibles. La toile aussi bien que la peau même du peintre. À la façon de l’amour, elle nous détourne d’un sens transcendant pour « nous confier à l’absence de secret, comme à notre geste le plus propre » . / "Reverie" (daydreaming) is a way for painting to try to escape in a perverse manner from the rigors of the picture. The layout of surfaces, of shades, material effects are but traces of its daytime ramblings. He who watches the reverie is mistaken into thinking reverie appears languid and as if it were asleep. Reverie of material and surfaces is a static detour that lets us reach what is already there, just like perversion can. Impudence plays at turning away from the cold crystallisation of the image by a game between background and foreground that get excited together on the surface of the painting. In order to feel something at last, painting is ready for anything : diverting objects, drowning, feigning depth, letting itself go, letting itself be absorbed, abandoning form and genre, negating others, etc. As a provocation only to be able to feel, the painting experience confirms the test of the senses as such and takes it in. It works by contagion and not by representation. It reproduces down to a letter surfaces open to the senses. The canvas as the painter's own skin. Just like love, it diverts us from a transcendental meaning to "entrust us to the absence of secret just leaving us with our truest gesture" .

Submitted to the Information Technology (IT) Department in conformity with the requirements for the degree of Doctor of Philosophy in Information Technology, Durban University of Technology. Durban, South Africa, 2016. / This doctoral research introduces an integration of satellite systems and new stratospheric platforms for weather observation, imaging and transfer of meteorological data to the ground infrastructures. Terrestrial configuration and satellite communication subsystems represent well-established technologies that have been involved in global satellite sensing and weather observation area for years. However, in recent times, a new alternative has emerged based on quasi-stationary aerial platforms located in the Stratosphere called High Altitude Platform (HAP) or Stratospheric Communication Platforms (SCP). The SCP systems seem to represent a dream come true for communication engineers since they preserve most of the advantages of both terrestrial and satellite communication systems. Today, SCP systems are able to help, in a more cost effective way, developments of space Earth sensing and weather observation and weather sensing and observation. This new system can provide a number of forms ranging from a low altitude tethered balloon to a high altitude (18 – 25 km) fuel-powered piloted aircraft, solar-powered unmanned airplanes and solar-powered airship.

Master of Arts / Department of Geography / John Harrington, Jr / Nighttime rainfall has long been thought of as an important component to the central Great Plains hydroclimate during the wettest three-month period known as the “late spring -early summer precipitation maximum.” Research has suggested that nocturnal rainfall in the region results from a phenomenon known as the nocturnal Great Plains Low-Level Jet (GPLLJ). The jet, which originates in the Gulf of Mexico, transports moisture into the Great plains during the nighttime hours and often provides fuel for nighttime convection. The climatological characteristics of nighttime rainfall, as well the configuration of the low-level winds and the mechanisms behind its formation during this three-month wet period, however; are not well understood. Using hourly rainfall data from Topeka, KS, the nighttime rainfall characteristics are examined Topeka, KS and other Kansas stations for a 63-year period from 1950-2012 for May-July. Additionally, using the NCEP/NCAR Reanalysis data, the structure and configuration of the southerly wind phenomenon was analyzed based on its horizontal and vertical characteristics for nighttime rainfall events in May, June and July. A subsequent analysis also analyzed the larger synoptic-scale environment in place for six half-month periods from May to July. The results indicate that nighttime rainfall is a major contributor to the overall moisture budget in the Great Plains, contributing close to 50% of the overall rainfall total for the three-month period. The percentage of nighttime rainfall increases from west-east across the state, as well as temporally from May to July. The southerly winds are at their strongest during May events, tends to reach its peak at 850 mb at 6z (0000LST) near south-central Oklahoma, and forms as the result of both synoptic and thermal mechanisms. The synoptic mechanisms in place that generate the a southerly wind component change by month, leading to incredible variation in terms of its characteristics during nighttime rainfall events.

To investigate seasonal patterns of precipitation, statistical analysis was performed on a dataset of daily rainfall observed at 63 south Louisiana stations from 1836 to 2002. Each station record was examined for data quality and continuity with special attention to time periods surrounding station relocation or equipment exchange. Mean Areal Precipitation (MAP) sheets were compiled for every month from 1836 to 2002 to document the daily rainfall across south Louisiana and neighboring portions of southern and coastal Mississippi. Using these MAP sheets, missing data was examined to see if a reasonable value could be substituted to extend the continuity of a station's rainfall record. Once these data quality and continuity checks were completed, a series of statistical tests were conducted to determine an accurate scheme to form station groups. To group stations together, each station was required to have a normal distribution of monthly average rainfall, a statistically equivalent variance, and a statistically equivalent mean when compared with other stations in the group. As a result of the Shapiro-Wilk Test, the F-Test, and the Student T-test, eight station groups were formed. To define seasonal rainfall patterns across south Louisiana, statistical tests were conducted for a 12 month period and six and three month intervals. For the six month intervals, group rainfall averages and pooled variances were calculated for each interval beginning with January-July and ending with December-May. For the three month intervals, group rainfall averages and pooled variances were calculated for January-March and concluded with December-February. To test the hypothesis of a statistically significant difference in mean rainfall between the eight groups for a 12, six, and three month period, the Student T-test was conducted. For an annual basis, there is a statistically significant difference in average rainfall at a five percent level of significance between all of the groups except the Southshore (S.S) group when compared to the SW1 group. For six and three month intervals, statistically significant differences exist between the eight groups especially during winter and segments of the Hurricane season from June to November.