Dimethylsulfide gas transfer coefficients from algal blooms in the Southern Ocean

Air���sea dimethylsulfide (DMS) fluxes and bulk air���sea gradients were measured over the Southern Ocean in February���March 2012 during the Surface Ocean Aerosol Production (SOAP) study. The cruise encountered three distinct phytoplankton bloom regions, consisting of two blooms with moderate DMS levels, and a high biomass, dinoflagellate-dominated bloom with high seawater DMS levels (> 15 nM). Gas transfer coefficients were considerably scattered at wind speeds above 5 m/s. Bin averaging the data resulted in a linear relationship between wind speed and mean gas transfer velocity consistent with that previously observed. However, the wind-speed-binned gas transfer data distribution at all wind speeds is positively skewed. The flux and seawater DMS distributions were also positively skewed, which suggests that eddy covariance-derived gas transfer velocities are consistently influenced by additional, log-normal noise. A flux footprint analysis was conducted during a transect into the prevailing wind and through elevated DMS levels in the dinoflagellate bloom. Accounting for the temporal/spatial separation between flux and seawater concentration significantly reduces the scatter in computed transfer velocity. The SOAP gas transfer velocity data show no obvious modification of the gas transfer���wind speed relationship by biological activity or waves. This study highlights the challenges associated with eddy covariance gas transfer measurements in biologically active and heterogeneous bloom environments.

Air-sea exchange of methanol and acetone during HiWinGS: Estimation of air phase, water phase gas transfer velocities

The air-sea fluxes of methanol and acetone were measured concurrently using a proton-transfer-reaction mass spectrometer (PTR-MS) with the eddy covariance (EC) technique during the High Wind Gas Exchange Study (HiWinGS) in 2013. The seawater concentrations of these compounds were also measured twice daily with the same PTR-MS coupled to a membrane inlet. Dissolved concentrations near the surface ranged from 7 to 28 nM for methanol and from 3 to 9 nM for acetone. Both gases were consistently transported from the atmosphere to the ocean as a result of their low sea surface saturations. The largest influxes were observed in regions of high atmospheric concentrations and strong winds (up to 25 m s(-1)). Comparison of the total air-sea transfer velocity of these two gases (K-a), along with the in situ sensible heat transfer rate, allows us to constrain the individual gas transfer velocity in the air phase (k(a)) and water phase (k(w)). Among existing parameterizations, the scaling of k(a) from the COARE model is the most consistent with our observations. The k(w) we estimated is comparable to the tangential (shear driven) transfer velocity previously determined from measurements of dimethyl sulfide. Lastly, we estimate the wet deposition of methanol and acetone in our study region and evaluate the lifetimes of these compounds in the surface ocean and lower atmosphere with respect to total (dry plus wet) atmospheric deposition.

Metocean Comparisons of Jason-2 and AltiKa���A Method to Develop a New Wind Speed Algorithm

As well as range, the AltiKa altimeter provides estimates of wave height, Hs and normalized backscatter, s0, that need to be assessed prior to statistics based on them being included in climate databases. An analysis of crossovers with the Jason-2 altimeter shows AltiKa Hs values to be biased high by only ��0.05m, with a standard deviation (s.d.) of ��0.1m for seven-point averages. AltiKa���s s 0 values are 2.5���3 dB less than those from Jason-2, with a s.d. of ��0.3 dB, with these relatively large mismatches to be expected as AltiKa measures a different part of the spectrum of sea surface roughness. A new wind speed algorithm is developed through matchinghistogram of s0 values to that for Jason-2 wind speeds. The algorithm is robust to the use of short durations of data, with a consistency at roughly the 0.1 m/s level. Incorporation of Hs as a secondary input reduces the assessed error at crossovers from 0.82 m/s to 0.71 m/s. A comparison across all altimeter frequencies used to date demonstrates that the lowest wind speeds preferentially develop the shortest scales of roughness.

Scaling up experimental ocean acidification and warming research: from individuals to the ecosystem

Understanding long-term, ecosystem-level impacts of climate change is challenging because experimental research frequently focuses on short-term, individual-level impacts in isolation. We address this shortcoming first through an inter-disciplinary ensemble of novel experimental techniques to investigate the impacts of 14-month exposure to ocean acidification and warming (OAW) on the physiology, activity, predatory behaviour and susceptibility to predation of an important marine gastropod (Nucella lapillus). We simultaneously estimated the potential impacts of these global drivers on N. lapillus population dynamics and dispersal parameters. We then used these data to parameterise a dynamic bioclimatic envelope model, to investigate the consequences of OAW on the distribution of the species in the wider NE Atlantic region by 2100. The model accounts also for changes in the distribution of resources, suitable habitat and environment simulated by finely resolved biogeochemical models, under three IPCC global emissions scenarios. The experiments showed that temperature had the greatest impact on individual level responses, while acidification has a similarly important role in the mediation of predatory behaviour and susceptibility to predators. Changes in Nucella predatory behaviour appeared to serve as a strategy to mitigate individual level impacts of acidification, but the development of this response may be limited in the presence of predators. The model projected significant large-scale changes in the distribution of Nucella by the year 2100 that were exacerbated by rising greenhouse gas emissions. These changes were spatially heterogeneous, as the degree of impact of OAW on the combination of responses considered by the model varied depending on local environmental conditions and resource availability. Such changes in macro-scale distributions cannot be predicted by investigating individual level impacts in isolation, or by considering climate stressors separately. Scaling up the results of experimental climate change research requires approaches that account for long-term, multi-scale responses to multiple stressors, in an ecosystem context.

Evaluating machine-learning techniques for recruitment forecasting of seven North East Atlantic fish species

The effect of different factors (spawning biomass, environmental conditions) on recruitment is a subject of great importance in the management of fisheries, recovery plans and scenario exploration. In this study, recently proposed supervised classification techniques, tested by the machine-learning community, are applied to forecast the recruitment of seven fish species of North East Atlantic (anchovy, sardine, mackerel, horse mackerel, hake, blue whiting and albacore), using spawning, environmental and climatic data. In addition, the use of the probabilistic flexible naive Bayes classifier (FNBC) is proposed as modelling approach in order to reduce uncertainty for fisheries management purposes. Those improvements aim is to improve probability estimations of each possible outcome (low, medium and high recruitment) based in kernel density estimation, which is crucial for informed management decision making with high uncertainty. Finally, a comparison between goodness-of-fit and generalization power is provided, in order to assess the reliability of the final forecasting models. It is found that in most cases the proposed methodology provides useful information for management whereas the case of horse mackerel is an example of the limitations of the approach. The proposed improvements allow for a better probabilistic estimation of the different scenarios, i.e. to reduce the uncertainty in the provided forecasts.

Exploring the links between urban stucture and air quality

A polui����o atmosf��rica constitui actualmente um grave problema ambiental cujos efeitos se fazem sentir a diversas escalas, desde os efeitos imediatos e de longo termo na sa��de humana e nos materiais, at�� fen��menos regionais, como a acifica����o, e fen��menos globais que durante este s��culo poder��o alterar as condi����es de vida no globo. Apesar da redu����o das emiss��es de poluentes atmosf��ricos, conseguida atrav��s do uso de combust��veis mais limpos e tecnologias mais eficientes, as ��reas urbanas continuam a evidenciar sinais de degrada����o ambiental. Para ser bem sucedida a cidade deve enfrentar as tr��s dimens��es da sustentabilidade: social, econ��mica e ambiental. O modo de utiliza����o do solo numa zona urbana �� uma caracter��stica fundamental da cidade, com influ��ncia directa no seu desempenho ambiental e na qualidade de vida que proporciona �� popula����o. O presente trabalho explora a liga����o entre a estrutura urbana e a qualidade do ar, um dos muitos aspectos do desenvolvimento urbano sustent��vel. A perspectiva hist��rica sobre o desenvolvimento urbano, a polui����o atmosf��rica e a sua interliga����o �� abordada, bem como o trabalho de investiga����o que tem vindo a ser conduzido na ��rea. A aplica����o de um sistema de modela����o atmosf��rico a um caso de estudo idealizado demonstra a import��ncia da estrutura espacial da cidade na sustentabilidade urbana, mostrando que cidades compactas com usos do solo misturados promovem uma melhor qualidade do ar quando comparadas com cidades dispersas, com baixa densidade populacional. De modo a explorar a rela����o entre a estrutura urbana e a qualidade do ar numa zona urbana real, a regi��o urbana do Porto �� identificada como um caso de estudo adequado, e o processo de crescimento urbano nas ��ltimas d��cadas �� analisado, assim como os n��veis de qualidade do ar da regi��o. De modo a definir a configura����o do sistema de modela����o mais adequada para a regi��o de estudo, s��o efectuados diversos testes de sensibilidade com o modelo meteorol��gico. Relativamente ao modelo de qualidade do ar, �� descrito e implementado um conjunto de ac����es de modo a melhorar o desempenho do modelo para a simula����o das concentra����es de poluentes na atmosfera urbana, no contexto de altera����es do uso do solo. Finalmente, s��o desenvolvidos e testados, atrav��s da aplica����o do sistema de modela����o, dois cen��rios alternativos de desenvolvimento urbano para a ��rea de estudo. Estes cen��rios alternativos implicam diferentes emiss��es de poluentes e diferentes distribui����es espaciais dessas emiss��es, e como consequ��ncia, diferentes n��veis de qualidade do ar. O estudo permite concluir que altera����es nos padr��es de uso do solo em ��reas urbanas conduzem a altera����es na meteorologia, emiss��es e qualidade do ar. As ��reas urbanas dispersas, quando comparadas com estruturas urbanas compactas s��o respons��veis por temperaturas mais elevadas, emiss��es de poluentes para a atmosfera mais elevadas e maiores concentra����es de poluentes.

Clubes de ci��ncias e o percurso escolar dos alunos

Os factores que levam os alunos, no final da escolaridade obrigat��ria, a escolher o seu percurso escolar s��o v��rios. Neste estudo procurou-se saber em que medida a frequ��ncia de Clubes na ��rea das Ci��ncias influenciam essa decis��o e, ainda, estudar como potenciar a sua organiza����o no sentido de que estes possam contribuir positivamente para as escolhas dos alunos por percursos escolares na ��rea das Ci��ncias. A investiga����o decorreu em duas fases. Na primeira fase, foi avaliada a influ��ncia dos Clubes de Ci��ncias na decis��o do percurso escolar dos alunos, no final da escolaridade b��sica. Nesta fase foram realizados os seguintes procedimentos: -Entrevista semi-estruturada realizada a sete professoras respons��veis de Clubes na ��rea das Ci��ncias F��sicas e Naturais, de 7 Escolas Secund��rias da regi��o de Aveiro. -Administra����o de um question��rio, constru��do com quest��es maioritariamente fechadas, a uma amostra de 106 alunos, do 10��Ano, provenientes de 11 Escolas Secund��rias da regi��o de Aveiro, que frequentaram Clubes na ��rea das Ci��ncias F��sicas e Naturais, no 3�� Ciclo. -Tratamento estat��stico das quest��es do question��rio, com recurso ao programa SPSS (Statistical Package for the Social Science) e an��lise de conte��do das quest��es abertas do question��rio e das entrevistas, recorrendose para o efeito �� constru����o de categorias de resposta. Na segunda fase concebeu-se e implementou-se um Clube de Ci��ncias. Nesta fase surgiu a cria����o do Clube: ���Educa����o para o Desenvolvimento Sustent��vel���, no qual foi desenvolvido o projecto: ���Constru����o e dinamiza����o de uma Esta����o Meteorol��gica���, numa Escola B��sica do 2�� e 3�� Ciclos do Concelho de Aveiro. Os resultados obtidos na primeira fase do estudo s��o reveladores da import��ncia que �� atribu��da ��s experi��ncias vivenciadas pelos alunos nos Clubes de Ci��ncias que frequentaram. Os temas/assuntos abordados foram essencialmente conte��dos ligados a ��reas do conhecimento das disciplinas de Ci��ncias. Predominaram as estrat��gias com base em trabalho de projecto e em actividades experimentais. Indicadores nacionais e internacionais t��m evidenciado um decr��scimo no n��mero de jovens que, na sua escolaridade, optam por estudos nas ��reas das Ci��ncias e da Tecnologia. Este decr��scimo tem sido um factor de preocupa����o ao n��vel das pol��ticas educativas, nomeadamente europeias, tornando-se urgente, por um lado, compreender o porqu�� desse facto e, por outro, encontrar formas de o minimizar. Os Clubes na perspectiva das respons��veis entrevistadas: (a) Surgem como uma oportunidade para melhorar as compet��ncias dos alunos ao n��vel do saber fazer; (b) Permitem confirmar e refor��ar a motiva����o e o gosto pelas Ci��ncias; (c) Podem, tamb��m, dar-lhes orienta����es para o futuro, embora esta n��o tenha sido uma preocupa����o expl��cita; (d) S��o do agrado dos alunos devido a apresentarem actividades n��o meramente acad��micas e formais. Os Clubes, na perspectiva dos alunos respondentes: (a) Aumentaram a motiva����o para estudar Ci��ncias; (b) Permitiram relacionar as Ci��ncias com o dia-a-dia; (c) Ajudaram na escolha do curso que frequentam no Ensino Secund��rio; (d) Contribu��ram para querer exercer uma profiss��o na ��rea das Ci��ncias. Na segunda fase do estudo, foi desenvolvido um trabalho de projecto que envolveu alunos do 3�� Ciclo. O tema do projecto, proposto e implementado, coincidiu com os dois temas menos abordados, nos Clubes frequentados pelos respondentes da primeira fase do estudo, Meteorologia e Tem��ticas com Impacto Social. Por outro lado o Clube pretendeu contribuir para a D��cada da Educa����o para o Desenvolvimento Sustentado, institu��da pelas Na����es Unidas, para fazer frente �� actual situa����o de emerg��ncia planet��ria. Uma estrat��gia privilegiada para formar cidad��os capazes de assumir atitudes e valores com vista ao desenvolvimento sustent��vel, passa pela Educa����o em todas as suas vertentes, nomeadamente a do ensino n��o formal, na qual se incluem os Clubes de Ci��ncias. ABSTRACT: National and international indicators have showed a decrease in the number of youngsters that, during their school course make their choices in the study areas of Science and Technology. This decreasing tendency has been a motive of concern as far as the European educational policies are concerned. Thus, it is urgent to understand the reason behind that situation and find ways to minimize it. There are various factors that make students choose their study areas in the end of their school course. This study aimed to find out how the Science Clubs can influence their decisions as well as to study new ways to improve their organization in such a way that they may contribute positively to the students��� choices of their school careers in the area of Science. The investigation was divided in two parts: in the first part, it was evaluated the level of the influence of the Science Clubs in the students��� school careers at the end of the elementary education. At this stage it was adopted the following procedure: -A semi-structured interview was applied to 7 female teachers that are responsible for the Natural and Physics Science Clubs, in secondary schools, in the region of Aveiro; -A mainly close-question questionnaire was applied to a sample of 106 students, in the 10th grade, in 11 secondary schools, in the region of Aveiro. These students have attended some Natural and Physics Science Clubs, during the 7th, 8th and 9th grades; -Statistical work of the questionnaire was done with the help of the SPSS programme (Statistical Package for the Social Science) as well as the analysis of the contents of the open-questions of the questionnaire and the interviews by means of the answer-category method. In the second part, a Science Club was planned and implemented. At this stage, a club was created - ���Education for the Sustainable Development��� - within which the following project was developed ��� ���Building and Development of a Meteorological Observatory���, at a 2nd and 3rd Ciclos (Stages) Elementary School, in Aveiro. The results of the first part of this study case have showed clearly the importance given to the experiences of the students while attending the Science Clubs. The themes/subjects studied were mainly science knowledgerelated contents. The strategies adopted were based on project work and experimental activities. A view of the Clubs by the people who are responsible for them: (a)The Clubs mean an opportunity for students to learn the know-how process; (b)They have provided the reinforcement of the motivation and preference for Science; (c)Although it was not the main concern with the clubs, the truth is that they can also give the students a sense of awareness for the future; (d)Students like to make part of the clubs because of their experimental character. A view of the Clubs by the students who make part of them: (a)The clubs have increased the level of motivation to study Science; (b)They have allowed a close perspective of the daily life reality; (c)They have helped with the choice of the Secondary School courses; (d)They have made students want a future professional career in the area of Science. In the second part of this study case, a project work was carried out involving 7th, 8th and 9th grade students. The subject of the project, considered and implemented, coincided with the two less boarded subjects, in the Clubs attended a course for the respondents of the first phase of the study, Meteorology and Thematic with Social Impact. The Club also aimed to contribute to the decade of the ���Education for the Sustained Future��� as settled by the United Nations in order to face the present emergency situation of the planet. The last but not the least, it is believed that, the best strategy to teach future citizens who are able to take the responsibility of their values and attitudes towards a sustainable future, is to provide them a type of Education that can teach them both the formal curriculum aspects and the informal ones, as it is the case of the Science Clubs.

Sistemas de recep����o de imagens de sat��lite: implementa����o e aplica����es

A presente disserta����o pretende focalizar-se sobre algumas aplica����es da detec����o remota por sat��lite. Assim, ser�� exposto neste trabalho o resultado do desenvolvimento de sistemas de recep����o de imagens obtidas por sat��lites de ��rbita polar e geostacion��ria, assim como um conjunto de tr��s aplica����es implementadas: a detec����o de focos de inc��ndio em Portugal com dados do MSG-1, o desenvolvimento de um conjunto de actividades de explora����o da Detec����o Remota no contexto do 1' Ciclo do Ensino B��sico e a valida����o dos resultados de previs��o do modelo de mesoescala MM5 com imagens de sat��lite. A an��lise destas imagens desempenha um papel crucial, por exemplo nos estudos sobre tempo e clima. �� por essa raz��o que tanto os Estados Unidos como outros pa��ses t��m vindo a desenvolver um esfor��o cont��nuo para que possam ser lan��ados novos sat��lites que permitam uma constante aquisi����o de conhecimentos sobre os fen��menos meteorol��gicos. Deste modo, a implementa����o de sistemas de recep����o que possibilitem transformar as medidas disponibilizadas por instrumentos a bordo de sat��lites em informa����o constitui um empreendimento de extrema utilidade para as mais diversas ��reas do saber (como as Geoci��ncias ou a Meteorologia), revestindo-se de in��meras aplica����es de interesse para a Sociedade, nomeadamente nos sectores agr��cola, energ��tico, dos transportes e da conserva����o do meio ambiente.

Regional and urban air quality modelling under a climate change scenario

The better understanding of the interactions between climate change and air quality is an emerging priority for research and policy. Climate change will bring changes in the climate system, which will affect the concentration and dispersion of air pollutants. The main objective of the current study is to assess the impacts of climate change on air quality in 2050 over Portugal and Porto urban area. First, an evaluation and characterization of the air quality over mainland Portugal was performed for the period between 2002 and 2012. The results show that NO2, PM10 and O3 are the critical pollutants in Portugal. Also, the influence of meteorology on O3, NO2 and PM10 levels was investigate in the national main urban areas (Porto and Lisboa) and was verified that O3 has a statistically significant relationship with temperature in most of the components. The results also indicate that emission control strategies are primary regulators for NO2 and PM10 levels. After, understanding the national air quality problems and the influence that meteorology had in the historical air quality levels, the air quality modelling system WRF-CAMx was tested and the required inputs for the simulations were prepared to fulfil the main goal of this work. For the required air quality modelling inputs, an Emission Projections under RCP scenarios (EmiPro-RCP) model was developed to assist the estimation of future emission inventories for GHG and common air pollutants. Also, the current emissions were estimated for Portugal with a higher detailed disaggregation to improve the performance of the air quality simulations. The air quality modelling system WRF/CAMx was tested and evaluated over Portugal and Porto urban area and the results point out that is an adequate tool for the analysis of air quality under climate change. For this purpose, regional simulations of air quality during historical period and future (2045-2050) were conducted with CAMx version 6.0 to evaluate the impacts of simulated future climate and anthropogenic emission projections on air quality over the study area. The climate and the emission projections were produced under the RCP8.5 scenario. The results from the simulations point out, that if the anthropogenic emissions keep the same in 2050, the concentrations of NO2, PM10 and O3 will increase in Portugal. When, besides the climate change effects, is consider the projected anthropogenic emissions the annual mean concentrations of NO2 decrease significantly in Portugal and Porto urban area, and on the contrary the annual mean PM10 concentrations increases in Portugal and decrease in Porto urban area. The O3 results are mainly caused by the reduction of ozone precursors, getting the higher reductions in urban areas and increases in the surrounding areas. All the analysis performed for both simulations for Porto urban area support that, for PM10 and O3, there will be an increase in the occurrence of extreme values, surpassing the annual legislated parameters and having more daily exceedances. This study constitutes an innovative scientific tool to help in future air quality management in order to mitigate future climate change impacts on air quality.

An evaluation of the accuracy of models for the determination of the weighted mean temperature of the atmosphere

The estimates of the zenith wet delay resulting from the analysis of data from space techniques, such as GPS and VLBI, have a strong potential in climate modeling and weather forecast applications. In order to be useful to meteorology, these estimates have to be converted to precipitable water vapor, a process that requires the knowledge of the weighted mean temperature of the atmosphere, which varies both in space and time. In recent years, several models have been proposed to predict this quantity. Using a database of mean temperature values obtained by ray-tracing radiosonde profiles of more than 100 stations covering the globe, and about 2.5 year���s worth of data, we have analyzed several of these models. Based on data from the European region, we have concluded that the models provide identical levels of precision, but different levels of accuracy. Our results indicate that regionally-optimized models do not provide superior performance compared to the global models.

A neural network seismic detector

This experimental study focuses on a detection system at the seismic station level that should have a similar role to the detection algorithms based on the ratio STA/LTA. We tested two types of neural network: Multi-Layer Perceptrons and Support Vector Machines, trained in supervised mode. The universe of data consisted of 2903 patterns extracted from records of the PVAQ station, of the seismography network of the Institute of Meteorology of Portugal. The spectral characteristics of the records and its variation in time were reflected in the input patterns, consisting in a set of values of power spectral density in selected frequencies, extracted from a spectro gram calculated over a segment of record of pre-determined duration. The universe of data was divided, with about 60% for the training and the remainder reserved for testing and validation. To ensure that all patterns in the universe of data were within the range of variation of the training set, we used an algorithm to separate the universe of data by hyper-convex polyhedrons, determining in this manner a set of patterns that have a mandatory part of the training set. Additionally, an active learning strategy was conducted, by iteratively incorporating poorly classified cases in the training set. The best results, in terms of sensitivity and selectivity in the whole data ranged between 98% and 100%. These results compare very favorably with the ones obtained by the existing detection system, 50%.

On-line operation of an intelligent seismic detector

This study describes the on-line operation of a seismic detection system to act at the level of a seismic station providing similar role to that of a STA /LTA ratio-based detection algorithms. The intelligent detector is a Support Vector Machine (SVM), trained with data consisting of 2903 patterns extracted from records of the PVAQ station, one of the seismographic network's stations of the Institute of Meteorology of Portugal (IM). Records' spectral variations in time and characteristics were reflected in the SVM input patterns, as a set of values of power spectral density at selected frequencies. To ensure that all patterns of the sample data were within the range of variation of the training set, we used an algorithm to separate the universe of data by hyper-convex polyhedrons, determining in this manner a set of patterns that have a mandatory part of the training set. Additionally, an active learning strategy was conducted, by iteratively incorporating poorly classified cases in the training set. After having been trained, the proposed system was experimented in continuous operation for unseen (out of sample) data, and the SVM detector obtained 97.7% and 98.7% of sensitivity and selectivity, respectively. The same type of ANN presented 88.4 % and 99.4% of sensitivity and selectivity when applied to data of a different seismic station of IM. �� 2013 Springer-Verlag Berlin Heidelberg.

Long-range Transport of Ambrosia Pollen to Poland

The long-range transport of Ambrosia pollen to Poland is intermittent and mainly related to the passage of air masses over the Carpathian and Sudetes mountains. These episodes are associated with hot dry weather, a deep Planetary Boundary Layer (PBL) in the source areas and winds from the south. Such episodes can transport significant amounts of Ambrosia pollen into Poland. The study investigates Ambrosia pollen episodes at eight sites in Poland during the period 7th to 10th September 2005, by examining temporal variations in Ambrosia pollen and back-trajectories. PBL depths in the likely source areas were calculated with the Eta meteorological model and evaluated against the mountain heights. Considerable amounts of Ambrosia pollen were recorded at several monitoring sites during the night or early in the morning of the investigated period. Trajectory analyses shows that the air masses arriving at the Polish sites predominantly came from the south, and were in the Czech Republic, Slovakia and Hungary the previous day indicating these countries as potential source areas. We have shown the progress of Ambrosia plumes into Poland from the south of the country, probably from Slovakia and Hungary, and demonstrated how Lagrangian back-trajectory models and meteorological models can be used to identify possible transport mechanisms of Ambrosia pollen from potential source regions.

A Method For Producing Airborne Pollen Source Inventories: An Example of Ambrosia (Ragweed) on the Pannonian Plain

We present here a simple methodology for calculating species inventories for allergenic pollen that can be used by atmospheric transport models. Ragweed (Ambrosia) species distribution or infection level on the Pannonian Plain has been used as an example of how the methodology can be used. The Pannonian Plain is one of the three main regions in Europe recognized as being polluted by Ambrosia. The methodology relies on spatial variations in annual Ambrosia pollen counts, knowledge on ragweed ecology and detailed land cover information. The results of this analysis showed that some of the highest mean annual ragweed pollen concentrations were witnessed around Kecskem��t in central Hungary and Novi Sad in northern Serbia. These areas are also the areas with the highest density of Ambrosia habitats. The resulting inventory can be entered into atmospheric transport models in combination with other components such as a phenological model and a model for daily pollen release, in order to simulate the movement of ragweed pollen from the Pannonian Plain. The methodology is likely to be generally applicable for creating inventories of species distribution of allergenic plants. The main requirement is availability of: detailed land cover information; pollen indexes; a list of the most important habitats; and a region of interest that is mainly influenced by local sources.