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The CALPHAD XLIX conference took place in Stockholm, Sweden, from May 22 to 27, 2022. 112 participants from 18 countries attended the conference. The scientific program included 69 oral presentations divided into 16 thematic topics and 27 posters., QC 20230412

The hemispheric symmetry of albedo and its contributing factors in satellite observations and global climate models is evaluated. The analysis is performed on the annual mean time scale, on which a bimodality in the joint distribution of albedo and cloud fraction is evident, resulting from tropical and subtropical clouds and midlatitude clouds, respectively. Hemispheric albedo symmetry is not found in individual ocean-only latitude bands; comparing the Northern and Southern Hemisphere (NH and SH), regional mean albedo is higher in the NH tropics and lower in the NH subtropics and midlatitudes than in the SH counterparts. This follows the hemispheric asymmetry of cloud fraction. In midlatitudes and tropics the hemispheric asymmetry in cloud albedo also contributes to the asymmetry in total albedo, whereas in the subtropics the cloud albedo is more hemispherically symmetric. According to the observations, cloud contributions to compensation for higher clear-sky albedo in the NH come primarily from cloud albedo in midlatitudes and cloud amount in the subtropics. Current-generation climate models diverge in their representation of these relationships, but common features of the model-data comparison include weaker-than-observed asymmetry in cloud fraction and cloud albedo in the tropics, weaker or reversed cloud fraction asymmetry in the subtropics, and agreement with observed cloud albedo asymmetry in the midlatitudes. Models on average reproduce the NH-SH asymmetry in total albedo over the 60 degrees S-60 degrees N ocean but show higher occurrence of brighter clouds in the SH compared to observations. The albedo bias in both hemispheres is reinforced by overestimated clear-sky albedo in the models.

Enligt lag har renskötare i Sverige rätt att bedriva rennäring på mark som de själva inte äger. Beträffande mark som ägs, eller som tidigare ägts, av staten är rättigheterna mer långtgående och renskötarna får där exempelvis avverka skog för att tillgodogöra sig både virke och bränsle som behövs för rennäringen. När staten säljer mark till enskilda ska Lantmäteriet sedan 30 juni 1992 skriva in en notering i fastighetsregistret för att upplysa om att utökad renskötselrätt föreligger. Studien är en uppföljning av hur denna upplysning hanterats vid förrättningar gjorda i Arvidsjaur, Gällivare och Vilhelmina kommun mellan år 1992 och 2017. Genom att i fastighetsregistret leta reda på och granska utdrag för de fastigheter som staten överfört mark till ämnar studien ge en bild av hur inskrivningsarbetet skötts. Försäljning av statlig mark har främst skett genom det statligt ägda Sveaskog AB. Det härleder ett naturligt urval i form av de marköverföringar som skett från fastigheter ägda av bolaget. Fastigheterna som i sin tur erhållit statlig mark kategoriseras efter om de har inskriven uppgift om utökad renskötselrätt samt efter vem som är lagfaren ägare till fastigheten. Detta avgör om hanteringen har utförts korrekt eller inte. I Gällivare har inskrivning av uppgiften felaktigt uteblivit vid 65 % av tillfällena och inte heller i Arvidsjaur eller Vilhelmina har arbetet utförts korrekt. Resultatet ger också en inblick i förrättningslantmätarnas arbetsrutiner kring hantering av uppgiften. Resultatet visar att de har utvecklat en arbetsmetodik som går längre än vad Lantmäteriets handledande dokument anger. Detta är en av de företeelser som analyseras i studiens resultatanalys- och diskussionsavsnitt. Studien belyser bakomliggande faktorer till varför uppgift om utökad renskötsel kan ha uteblivit. Diskussion förs kring upplysningens tydlighet gentemot fastighetsägare samt hur uppgiften kan omformuleras och förtydligas så att alla ges möjlighet att förstå dess innebörd. De slu, Reindeer keepers in Sweden have the right to pursue reindeer husbandry on land that they do not own. That is governed by law. The rights are more extensive regarding land that is now, or formerly was, owned by the Swedish state. The reindeer keepers may for example cut down trees in order to collect wood and fuel needed for their business. Lantmäteriet (the Swedish mapping, cadastral and land registration authority) shall since 30 June 1992 insert a comment in the real property register to inform about the existence of the extensive right of reindeer keeping, actuated when the state sells land to a private owner. The main focus of the study is to investigate how Lantmäteriet has handled the insertion of such information in Arvidsjaur, Gällivare and Vilhelmina municipality between year 1992 and 2017. By finding and examining transcripts from the real property register on properties which the state has sold land to, the study aims to show how the task has been handled. The sale of land owned by the state has mainly been managed by the company Sveaskog AB. This derives a natural selection consisting of land transfers made from properties owned by that company. The properties that have received land are categorized with respect to whether they have information about the extensive right of the reindeer keepers and to who the owner of the property is. This determines whether the task has been handled correctly or not. The information has been incorrectly left out in 65 % of the insertions in Gällivare and nor in Arvidsjaur or Vilhelmina has the work been done correctly. The result also gives an insight into the working routines of the cadastral surveyors and it shows how they approached the task. They seem to have developed an approach that goes beyond what is written in the guidelines from Lantmäteriet. This is one of the phenomena which is further discussed in the analysis. The study analyzes the underlying factors to why the information is not inserted. A discussion i

A thermoplastic finite strain model is used to model heat generation due to plastic work. Isotropic hardening is used, where the mechanical dissipation acts as heat source in the heat equation. The multiplicative split of the deformation gradient makes it possible to separate plastic and elastic effects. The model is solved by using the Newmark time integration scheme with the finite element method using total Lagrangian formulation. The model is also aimed for implementation with gradient based topology optimization for finite strains with the objective to maximize the the plastic dissipation. The method of moving asymptotes (MMA) is used in the optimization to make the problem convex. The sensitivities required to form the gradient is calculated using the adjoint method where the sensitivities are derived for the thermoplastic case. Helmholtz’s partial differential equation is used for regularization and a Heaviside filter is used to make the topology more precise., Kan man låta datorn bestämma den säkraste designen för en bil? och kommer en ökning av temperaturen i det använda materialet att påverka denna design? I examensarbetet ”Thermoplasticity in topology optimization based on finite strain” undersöks hur den genererade temperaturen vid en snabb och stor ihoptryckning av en struktur påverkar den design som ̈är bäst på att absorbera energi vid t.ex. en krock. Det visar sig att temperaturen har en avsevärd inverkan på den bästa designen.

This study focuses on the radiative properties of five subtropical marine stratocumulus cloud regions, on monthly mean scale. Through examination of the relation between total albedo and cloud fraction, and its variability and relation to other parameters, some of the factors controlling the reflectivity, or albedo, of the clouds in these regions are investigated. It is found that the main part of the variability in albedo at a given cloud fraction can be related to temporal, rather than spatial variability, indicating spatial homogeneity in cloud radiative properties in the studied regions. This is seen most clearly in satellite observations, but also in an ensemble of climate models. Further comparison between satellite data and output from climate models shows that there is good agreement with respect to the role of liquid water path, the parameter that can be assumed to be the primary source of variability in cloud reflectivity for a given cloud fraction. On the other hand, the influence of aerosol loading on cloud albedo differs between models and observations. The cloud-albedo effect, or cloud brightening caused by aerosol through its coupling to cloud droplet number concentration and droplet size, is found not to dominate in the satellite observations on monthly mean scale, as it appears to do on this scale in the climate models. The disagreement between models and observations is particularly strong in regions with frequent occurrence of absorbing aerosols above clouds, where satellite data contrary to the climate models indicate a scene darkening with increasing aerosol loading.

Earth's albedo is the primary determinant of the amount of energy absorbed by the Earth-atmosphere system. It is a function of the fractional cloud cover and the cloudy-and clear-sky albedos, and thereby of the aerosol loading of the atmosphere. Here, we introduce a method by which we can examine the spatial distribution of the albedo variability that is independent of variations in the two dominant factors of albedo: cloud fraction and liquid water path (LWP). The analysis is based on data simultaneously retrieved from the CERES and MODIS instruments carried on board the Aqua satellite. We analysed the daily overpass data between July 2002 and June 2014 and showed that perturbations in albedo, accounting for variations induced by cloud fraction and LWP, display a coherent geographical pattern. Positive deviations occur in proximity to known anthropogenic aerosol sources, and negative deviations coincide with areas of intense precipitation, acting as aerosol sinks. A simple multiplication of the observed positive perturbations in albedo with the solar flux of 340Wm(-2) yields a magnitude of that effect of several watts per square meter locally. While the location and scale of the geographical pattern might suggest an anthropogenic contribution to the positive albedo perturbations, it is imperative to first carefully examine all other possible causal factors behind the perturbations. Finally, although we have not attempted a full calculation of detection limits, the analysis is capable of sensing very small changes in average albedo of the order of 0.003 out of a total albedo of the order of 0.3. Hence, the applied method might find utilisation in a variety of situations where there is a need to quantify small perturbations of a dependent variable in noisy global data sets., AuthorCount:4

We study the relation between monthly mean albedo and cloud fraction over ocean,60∘S–60∘N. Satellite obser vations indicate that these clouds all fall on the same near-exponential curve,with a monotonic distribution over the ranges of cloud fractions and albedo. Using these observational dataas a reference, we examine the degree to which 26 climate models capture this feature of the near-globalmarine cloud population. Models show a general increase in albedo with increasing cloud fraction, but noneof them display a relation that is as well defined as that characterizing the observations. Models t ypicallydisplay larger albedo variability at a given cloud fraction, larger sensitivity in albedo to changes in cloudfraction, and lower cloud fractions. Several models also show branched distributions, contrasting with thesmooth observational relation. In the models the present-day cloud scenes are more reflective than thepreindustrial, demonstrating the simulated impact of anthropogenic aerosols on planetary albedo.

Recent cloud-resolving model studies of single (isolated) deep convective clouds have shown contradicting results regarding the response of the deep convection to changes in the aerosol concentration. In the present study, a cloud-resolving model including explicit aerosol physics and chemistry is used to examine how the complexity of the aerosol model, the size of the aerosols, and the aerosol activation parameterization influence the aerosol-induced deep convective cloud sensitivity. Six sensitivity series are conducted. A significant difference in the aerosol-induced deep convective cloud sensitivity is found when using different complexities of the aerosol model and different aerosol activation parameterizations. In particular, graupel impaction scavenging of aerosols appears to be a crucial process because it efficiently may limit the number of cloud condensation nuclei (CCN) at a critical stage of cloud development and thereby dampen the convection. For the simulated case, a 100% increase in aerosol concentration results in a difference in average updraft between the various sensitivity series that is as large as the average updraft increase itself. The change in graupel and rain formation also differs significantly. The sign of the change in precipitation is not always directly proportional to the change in updraft velocity and several of the sensitivity series display a decrease of the rain amount with increasing updraft velocity. This result illustrates the need to account for changes in evaporation processes and subsequent cooling when assessing aerosol effects on deep convective strength. The model simulations also show that an increased number of aerosols in the Aitken mode (here defined by 23 <= d <= 100.0 nm) results in a larger impact on the convective strength compared to an increased number of aerosols in the accumulation mode (here defined by 100 <= d <= 900.0 nm). When accumulation mode aerosols are activated and grow at the beginning, authorCount :3

Clouds may respond strongly to changes in the atmospheric aerosol population, and the response of clouds to an increased global aerosol burden could to some extent mask the warming caused by enhanced greenhouse gas concentrations. However, estimates of the impact of aerosols on cloud properties are associated with large uncertainties, both because of difficulties representing the aerosol-cloud interaction within models, and because of problems of unequivocally isolating the effect of aerosols on cloud properties in observational data. This thesis focuses in part on underlying meteorological factors that significantly correlate with both aerosol and cloud properties, and on how sensitive clouds are to small variations in meteorological conditions. It was found that meteorological covariations must be taken into account when estimating the strength of the relationship between aerosols and cloud properties. By studying the response of shallow convective clouds to perturbations in meteorological conditions and aerosol concentration, it was further concluded that variations in meteorological conditions can enhance or mask the relationship between aerosols and cloud properties, making it difficult to isolate the aerosol signature from small meteorological differences. Additionally, the impact of deep convective clouds on the redistribution of aerosols within a cloud life cycle is examined. It was found that mid-tropospheric aerosols can have a substantial source in evaporating cloud droplets within deep convection. Lastly, this thesis focuses on the implications of meteorological analysis uncertainties, in part related to the difficulties of constraining meteorological variability in observational data of clouds and aerosols, but mainly the impact of analysis errors on atmospheric trajectory calculations. A method is presented to consistently estimate the uncertainty in trajectory calculations. It was concluded that the spatial and temporal trajectory error can be substan, At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.

Historically, the field of materials science and engineering has focused on establishing the processing-structure- property relationships of materials through experimental trial and error with an understanding of the influence of microstructure—the microstructure, processing, and chemistry all being directly related to the crystallography, kinetics, and thermodynamics of the materials. In comparatively recent years, as computational methods have evolved, it has been possible to predict some such properties and relationships through numerical simulation., QC 20120418

The aerosol optical depth has in several recent studies been found to correlate with cloud fraction. This study examines the global distribution of the total correlation between aerosol optical depth, cloud fraction and meteorological conditions using satellite observations together with atmospheric re-analysis data from the ECMWF. The results show large regional differences in the correlation between aerosol optical depth and cloud fraction, where a higher correlation is found over remote ocean. The one meteorological variable that correlates significantly with both aerosol optical depth and cloud fraction is the 10-meter wind speed. Constructing the partial correlation between aerosol optical depth and cloud fraction, with the impact from 10-meter wind speed removed, yields a significant difference compared to the total correlation. In several regions the remaining partial correlation is reduced from 0.4 to below 0.1. The results highlight the need to investigate all possible correlations between meteorological variables, cloud properties and aerosols. Citation: Engstrom, A., and A. M. L. Ekman (2010), Impact of meteorological factors on the correlation between aerosol optical depth and cloud fraction, authorCount :2

The uncertainty of a calculated trajectory is dependent on the uncertainty in the atmospheric analysis. Using the Ensemble Transform method (originally adapted for ensemble forecasting) we sample the analysis uncertainty in order to create an ensemble of analyses where a trajectory is started from each perturbed analysis. This method, called the Ensemble analysis method (EA), is compared to the Initial spread method (IS), where the trajectory receptor point is perturbed in the horizontal and vertical direction to create a set of trajectories used to estimate the trajectory uncertainty. The deviation growth is examined for one summer and one winter month and for 15 different geographical locations. We find up to a 40% increase in trajectory deviation in the mid-latitudes using the EA method. A simple model for trajectory deviation growth speed is set up and validated. It is shown that the EA method result in a faster error growth compared to the IS method. In addition, two case studies are examined to qualitatively illustrate how the flow dependent analysis uncertainty can impact the trajectory calculations. We find a more irregular behavior for the EA trajectories compared to the IS trajectories and a significantly increased uncertainty in the trajectory origin. We conclude that by perturbing the analysis in agreement with the analysis uncertainties the error in backward trajectory calculations can be more consistently estimated.

År 1987 trädde en ny byggnadslag i kraft, Plan- och bygglagen(PBL). I och med den nya lagen minskade kommunens och byggnadsnämndens kontroll av projekteringshandlingar och besiktningar ute på arbetsplatsen. Efter lagändringen beror den slutgiltiga kvaliteten på en byggnad i större utsträckning på byggherrens och entreprenörernas egenkontroll. P.g.a. olika intressekonflikter inom kommunen, och att det kan förekomma starka kopplingar mellan byggherre och entreprenör, är det inte alltid självklart att kommunens tillsyn vid nybyggnation gällande till exempel egenskapskrav på energihushållning och värmeisolering utförs tillfredsställande.Med ovanstående i åtanke undersökte vi fyra flerbostadshus, två i Värnamo kommun samt två i Kristianstad. Vi undersökte om husen uppfyller de ställda värmeisoleringskraven enligt BBR(Boverkets Byggregler) 9 Kap. samt vilka krav som fanns med i respektive projekts kontrollplan. Endast ett av de fyra husen uppfyllde de ställda kraven. I kommunens kontrollplaner för de undersökta objekten ställs krav på värmeisoleringsberäkningar men några beräkningar på detta finns ej arkiverade hos kommunerna., In 1987, a new law of building became effective, Plan- och bygglagen(PBL). The building committees' inspection of construction sites and documents decreased. The final quality of the buildings now depended in greater extent on the property developers and the contractors internal control. Due to different interests within the municipality and because of strong connections between property developers and contractors, it is not always a matter of course that e.g. the inspection of thermal insulation and energy housekeeping is executed in a satifactory fashion. With the above in mind we examined four multi-dwelling buildings, two in municipality of Värnamo and two in Kristianstad. We examined if the buildings comply with the thermal insulation requirement according to BBR (the swedish building code) and which requirements that were stated in the different projects documents of inspection.Only one out of the four buildings complies with the requirements according to BBR. In the municipality documents there are requirements of thermal insulation calculations but there are no documents that verifies that such calculations have been executed.

3-D cloud-resolving model simulations including explicit aerosol physics and chemistry are compared with observations of upper tropospheric (12 km) aerosol size distributions over the Amazon Basin. The model underestimates the aerosol number concentration for all modes, especially the nucleation mode (d< 18nm). We show that a boundary layer SO2 mixing ratio of approximately 5 ppb would be needed in order to reproduce the high nucleation mode number concentrations observed. This high SO2 mixing ratio is very unlikely for the pristine Amazon Basin at this time of the year. Hence, it is suggested that vapours other than H2SO4 participate in the formation and growth of small aerosols. Using activation nucleation theory together with a small (0.4-10%) secondary organic aerosol mass yield, we show that isoprene has the potential of substantially increasing the number of small particles formed as well as reducing the underestimate for the larger aerosol modes.