Stationary in-situ measurements of aerosols, gaseous pollutants and meteorology : chemical and physical characterization of natural and anthropogenic sources

Natural and anthropogenic emissions of gaseous and particulate matter affect the chemical composition of the atmosphere, impact visibility, air quality, clouds and climate. Concerning climate, a comprehensive characterization of the emergence, composition and transformation of aerosol particles is relevant as their influence on the radiation budget is still rarely understood. Regarding air quality and therefore human health, the formation of atmospheric aerosol particles is of particular importance as freshly formed, small particles penetrate into the human alveolar region and can deposit. Additionally, due to the long residence times of aerosol particles in the atmosphere it is crucial to examine their chemical and physical characteristics.This cumulative dissertation deals with stationary measurements of particles, trace gases and meteorological parameters during the DOMINO (Diel Oxidant Mechanism In relation to Nitrogen Oxide) campaign at the southwest coast of Spain in November/December 2008 and the ship emission campaign on the banks of the Elbe in Freiburg/Elbe in April 2011. Measurements were performed using the Mobile research Laboratory “MoLa” which is equipped with state-of-the-art aerosol particle and trace gas instruments as well as a meteorological station.

The sensitivity of the photostationary state of NOx and its implication for the oxidation capacity in a semi-rural and boreal forest region

Für das Vermögen der Atmosphäre sich selbst zu reinigen spielen Stickstoffmonoxid (NO) und Stickstoffdioxid (NO2) eine bedeutende Rolle. Diese Spurengase bestimmen die photochemische Produktion von Ozon (O3) und beeinflussen das Vorkommen von Hydroxyl- (OH) und Nitrat-Radikalen (NO3). Wenn tagsüber ausreichend Solarstrahlung und Ozon vorherrschen, stehen NO und NO2 in einem schnellen photochemischen Gleichgewicht, dem „Photostationären Gleichgewichtszustand“ (engl.: photostationary state). Die Summe von NO und NO2 wird deshalb als NOx zusammengefasst. Vorhergehende Studien zum photostationären Gleichgewichtszustand von NOx umfassen Messungen an unterschiedlichsten Orten, angefangen bei Städten (geprägt von starken Luftverschmutzungen), bis hin zu abgeschiedenen Regionen (geprägt von geringeren Luftverschmutzungen). Während der photochemische Kreislauf von NO und NO2 unter Bedingungen erhöhter NOx-Konzentrationen grundlegend verstanden ist, gibt es in ländlicheren und entlegenen Regionen, welche geprägt sind von niedrigeren NOx-Konzetrationen, signifikante Lücken im Verständnis der zugrundeliegenden Zyklierungsprozesse. Diese Lücken könnten durch messtechnische NO2-Interferenzen bedingt sein - insbesondere bei indirekten Nachweismethoden, welche von Artefakten beeinflusst sein können. Bei sehr niedrigen NOx-Konzentrationen und wenn messtechnische NO2-Interferenzen ausgeschlossen werden können, wird häufig geschlussfolgert, dass diese Verständnislücken mit der Existenz eines „unbekannten Oxidationsmittels“ (engl.: unknown oxidant) verknüpft ist. Im Rahmen dieser Arbeit wird der photostationäre Gleichgewichtszustand von NOx analysiert, mit dem Ziel die potenzielle Existenz bislang unbekannter Prozesse zu untersuchen. Ein Gasanalysator für die direkte Messung von atmosphärischem NO¬2 mittels laserinduzierter Fluoreszenzmesstechnik (engl. LIF – laser induced fluorescence), GANDALF, wurde neu entwickelt und während der Messkampagne PARADE 2011 erstmals für Feldmessungen eingesetzt. Die Messungen im Rahmen von PARADE wurden im Sommer 2011 in einem ländlich geprägten Gebiet in Deutschland durchgeführt. Umfangreiche NO2-Messungen unter Verwendung unterschiedlicher Messtechniken (DOAS, CLD und CRD) ermöglichten einen ausführlichen und erfolgreichen Vergleich von GANDALF mit den übrigen NO2-Messtechniken. Weitere relevante Spurengase und meteorologische Parameter wurden gemessen, um den photostationären Zustand von NOx, basierend auf den NO2-Messungen mit GANDALF in dieser Umgebung zu untersuchen. Während PARADE wurden moderate NOx Mischungsverhältnisse an der Messstelle beobachtet (10^2 - 10^4 pptv). Mischungsverhältnisse biogener flüchtige Kohlenwasserstoffverbindungen (BVOC, engl.: biogenic volatile organic compounds) aus dem umgebenden Wald (hauptsächlich Nadelwald) lagen in der Größenordnung 10^2 pptv vor. Die Charakteristiken des photostationären Gleichgewichtszustandes von NOx bei niedrigen NOx-Mischungsverhältnissen (10 - 10^3 pptv) wurde für eine weitere Messstelle in einem borealen Waldgebiet während der Messkampagne HUMPPA-COPEC 2010 untersucht. HUMPPA–COPEC–2010 wurde im Sommer 2010 in der SMEARII-Station in Hyytiälä, Süd-Finnland, durchgeführt. Die charakteristischen Eigenschaften des photostationären Gleichgewichtszustandes von NOx in den beiden Waldgebieten werden in dieser Arbeit verglichen. Des Weiteren ermöglicht der umfangreiche Datensatz - dieser beinhaltet Messungen von relevanten Spurengasen für die Radikalchemie (OH, HO2), sowie der totalen OH-Reaktivität – das aktuelle Verständnis bezüglich der NOx-Photochemie unter Verwendung von einem Boxmodell, in welches die gemessenen Daten als Randbedingungen eingehen, zu überprüfen und zu verbessern. Während NOx-Konzentrationen in HUMPPA-COPEC 2010 niedriger sind, im Vergleich zu PARADE 2011 und BVOC-Konzentrationen höher, sind die Zyklierungsprozesse von NO und NO2 in beiden Fällen grundlegend verstanden. Die Analyse des photostationären Gleichgewichtszustandes von NOx für die beiden stark unterschiedlichen Messstandorte zeigt auf, dass potenziell unbekannte Prozesse in keinem der beiden Fälle vorhanden sind. Die aktuelle Darstellung der NOx-Chemie wurde für HUMPPA-COPEC 2010 unter Verwendung des chemischen Mechanismus MIM3* simuliert. Die Ergebnisse der Simulation sind konsistent mit den Berechnungen basierend auf dem photostationären Gleichgewichtszustand von NOx.

Impact of weather and climate on the incidence of acute coronary syndromes

BACKGROUND: First investigations of the interactions between weather and the incidence of acute myocardial infarctions date back to 1938. The early observation of a higher incidence of myocardial infarctions in the cold season could be confirmed in very different geographical regions and cohorts. While the influence of seasonal variations on the incidence of myocardial infarctions has been extensively documented, the impact of individual meteorological parameters on the disease has so far not been investigated systematically. Hence the present study intended to assess the impact of the essential variables of weather and climate on the incidence of myocardial infarctions. METHODS: The daily incidence of myocardial infarctions was calculated from a national hospitalization survey. The hourly weather and climate data were provided by the database of the national weather forecast. The epidemiological and meteorological data were correlated by multivariate analysis based on a generalized linear model assuming a log-link-function and a Poisson distribution. RESULTS: High ambient pressure, high pressure gradients, and heavy wind activity were associated with an increase in the incidence of the totally 6560 hospitalizations for myocardial infarction irrespective of the geographical region. Snow- and rainfall had inconsistent effects. Temperature, Foehn, and lightning showed no statistically significant impact. CONCLUSIONS: Ambient pressure, pressure gradient, and wind activity had a statistical impact on the incidence of myocardial infarctions in Switzerland from 1990 to 1994. To establish a cause-and-effect relationship more data are needed on the interaction between the pathophysiological mechanisms of the acute coronary syndrome and weather and climate variables.

A QUANTITATIVE INVESTIGATION OF SOURCE AND ELEMENTAL COMPOSITION OF INDOOR AND OUTDOOR FINE PARTICULATE AIR POLLUTION IN HOUSTON (TEXAS)

An investigation was undertaken to determine the chemical characterization of inhalable particulate matter in the Houston area, with special emphasis on source identification and apportionment of outdoor and indoor atmospheric aerosols using multivariate statistical analyses.^ Fine (<2.5 (mu)m) particle aerosol samples were collected by means of dichotomous samplers at two fixed site (Clear Lake and Sunnyside) ambient monitoring stations and one mobile monitoring van in the Houston area during June-October 1981 as part of the Houston Asthma Study. The mobile van allowed particulate sampling to take place both inside and outside of twelve homes.^ The samples collected for 12-h sampling on a 7 AM-7 PM and 7 PM-7 AM (CDT) schedule were analyzed for mass, trace elements, and two anions. Mass was determined gravimetrically. An energy-dispersive X-ray fluorescence (XRF) spectrometer was used for determination of elemental composition. Ion chromatography (IC) was used to determine sulfate and nitrate.^ Average chemical compositions of fine aerosol at each site were presented. Sulfate was found to be the largest single component in the fine fraction mass, comprising approximately 30% of the fine mass outdoors and 12% indoors, respectively.^ Principal components analysis (PCA) was applied to identify sources of aerosols and to assess the role of meteorological factors on the variation in particulate samples. The results suggested that meteorological parameters were not associated with sources of aerosol samples collected at these Houston sites.^ Source factor contributions to fine mass were calculated using a combination of PCA and stepwise multivariate regression analysis. It was found that much of the total fine mass was apparently contributed by sulfate-related aerosols. The average contributions to the fine mass coming from the sulfate-related aerosols were 56% of the Houston outdoor ambient fine particulate matter and 26% of the indoor fine particulate matter.^ Characterization of indoor aerosol in residential environments was compared with the results for outdoor aerosols. It was suggested that much of the indoor aerosol may be due to outdoor sources, but there may be important contributions from common indoor sources in the home environment such as smoking and gas cooking. ^

Sensible and latent heat fluxes in the atmospheric surface layer over the equatorial Atlantic (Appendix)

During a four weeks anchoring station of R.V. ,,Meteor" on the equator at 30° W longitude, vertical profiles of wind, temperature, and humidity were measured by means of a meteorological buoy carrying a mast of 10 m height. After eliminating periods of instrumental failure, 18 days are available for the investigation of the diurnal variations of the meteorological parameters and 9 days for the investigation of the vertical heat fluxes. The diurnal variations of the above mentioned quantities are caused essentially by two periodic processes: the 24-hourly changing solar energy supply and the 12-hourly oscillation of air pressure, which both originate in the daily rotation of the earth. While the temperature of the water and of the near water layers of the air show a 24 hours period in their diurnal course, the wind speed, as a consequence of the pressure wave, has a 12 hours period, which is also observable in evaporation and, consequently, in the water vapor content of the surface layer. Concerning the temperature, a weak dependence of the daily amplitude on height was determined. Further investigation of the profiles yields relations between the vertical gradients of wind, temperature, and water vapor and the wind speed, the difference between sea and air of temperature and water vapor, respectively, thus giving a contribution to the problem of parameterizing the vertical fluxes. Mean profile coefficients for the encountered stabilities, which were slightly unstable, are presented, and correction terms are given due to the fact that the conditions at the very surface are not sufficiently represented by measuring in a water depth of 20 cm and assuming water vapor saturation. This is especially true for the water vapor content, where the relation between the gradient and the air-sea difference suggests a reduction of relative humidity to appr. 96% at the very surface, if the gradients are high. This effect may result in an overestimation of the water vapor flux, if a ,,bulk"-formula is used. Finally sensible and latent heat fluxes are computed by means of a gradient-formula. The influence of stability on the transfer process is taken into account. As the air-sea temperature differences are small, sensible heat plays no important role in that region, but latent heat shows several interesting features. Within the measuring period of 18 days, a regular variation by a factor of ten is observed. Unperiodic short term variations are superposed by periodic diurnal variations. The mean diurnal course shows a 12-hours period caused by the vertical wind speed gradient superposed by a 24-hours period due to the changing stabilities. Mean values within the measuring period are 276 ly/day for latent heat and 9.41y/day for sensible heat.

Underway measurements of halocarbons (air) during POSEIDON cruise POS399 in June 2010

During the DRIVE (Diurnal and Regional Variability of Halogen Emissions) ship campaign we investigated the variability of the halogenated very short-lived substances (VSLS) bromoform (CHBr3), dibromomethane (CH2Br2) and methyl iodide (CH3I) in the marine atmospheric boundary layer in the eastern tropical and subtropical North Atlantic Ocean during May/June 2010. The highest VSLS mixing ratios were found near the Mauritanian coast and close to Lisbon (Portugal). With backward trajectories we identified predominantly air masses from the open North Atlantic with some coastal influence in the Mauritanian upwelling area, due to the prevailing NW winds. The maximum VSLS mixing ratios above the Mauritanian upwelling were 8.92 ppt for bromoform, 3.14 ppt for dibromomethane and 3.29 ppt for methyl iodide, with an observed maximum range of the daily mean up to 50% for bromoform, 26% for dibromomethane and 56% for methyl iodide. The influence of various meteorological parameters - such as wind, surface air pressure, surface air and surface water temperature, humidity and marine atmospheric boundary layer (MABL) height - on VSLS concentrations and fluxes was investigated. The strongest relationship was found between the MABL height and bromoform, dibromomethane and methyl iodide abundances. Lowest MABL heights above the Mauritanian upwelling area coincide with highest VSLS mixing ratios and vice versa above the open ocean. Significant high anti-correlations confirm this relationship for the whole cruise. We conclude that especially above oceanic upwelling systems, in addition to sea-air fluxes, MABL height variations can influence atmospheric VSLS mixing ratios, occasionally leading to elevated atmospheric abundances. This may add to the postulated missing VSLS sources in the Mauritanian upwelling region (Quack et al., 2007).

Underway water measurements of halocarbons during POSEIDON cruise POS399 in June 2010

Methyl iodide (CH3I), bromoform (CHBr3) and dibromomethane (CH2Br2), which are produced naturally in the oceans, take part in ozone chemistry both in the troposphere and the stratosphere. The significance of oceanic upwelling regions for emissions of these trace gases in the global context is still uncertain although they have been identified as important source regions. To better quantify the role of upwelling areas in current and future climate, this paper analyzes major factors that influenced halocarbon emissions from the tropical North East Atlantic including the Mauritanian upwelling during the DRIVE expedition. Diel and regional variability of oceanic and atmospheric CH3I, CHBr3 and CH2Br2 was determined along with biological and meteorological parameters at six 24 h-stations. Low oceanic concentrations of CH3I from 0.1-5.4 pmol/L were equally distributed throughout the investigation area. CHBr3 of 1.0-42.4 pmol/L and CH2Br2 of 1.0-9.4 pmol/L were measured with maximum concentrations close to the Mauritanian coast. Atmospheric mixing rations of CH3I of up to 3.3, CHBr3 to 8.9 and CH2Br2 to 3.1 ppt above the upwelling and 1.8, 12.8, respectively 2.2 ppt at a Cape Verdean coast were detected during the campaign. While diel variability in CH3I emissions could be mainly ascribed to oceanic non-biological production, no main driver was identified for its emissions in the entire study region. In contrast, oceanic bromocarbons resulted from biogenic sources which were identified as regional drivers of their sea-to-air fluxes. The diel impact of wind speed on bromocarbon emissions increased with decreasing distance to the coast. The height of the marine atmospheric boundary layer (MABL) was determined as an additional factor influencing halocarbon emissions. Oceanic and atmospheric halocarbons correlated well in the study region and in combination with high oceanic CH3I, CHBr3 and CH2Br2 concentrations, local hot spots of atmospheric halocarbons could solely be explained by marine sources. This conclusion is in contrast with previous studies that hypothesized the occurrence of elevated atmospheric halocarbons over the eastern tropical Atlantic mainly originating from the West-African continent.

Palaeoclimate reconstructions of the Oligocene to Pliocene from eight sites in northwest Germany using the Coexistence Approach

The first detailed reconstruction of the continental palaeoclimate evolution of the Northwest German Tertiary (Late Oligocene to Pliocene) is presented. The paleoclimate data are derived from the paleobotanical record using the coexistence approach, a method recently introduced that employs climatic requirements of the Nearest Living Relatives of a fossil flora. Twenty six megafloras (fruits and seeds, leaves, woods) from the Tertiary succession of the Lower Rhine Basin and neighboring areas are analyzed with respect to ten meteorological parameters. Additionally, two sample sets from Late Miocene to Early Pliocene sediments comprising 396 palynofloras are analyzed by the same method providing a higher temporal resolution. The temperature curves show a comparatively cooler phase in the Late Oligocene, a warm interval the Middle Miocene, and a cooling starting at 14 Ma. The cooling trend persisted until Late Pliocene with a few higher frequency temperature variations observed. From the beginning of Late Miocene to the present, the seasonality increases and climate appears to have been less stable. As indicated by the precipitation data, a Cfa climate with wet summers persisted in NW Germany from Late Oligocene to Late Pliocene. The results obtained are well in accordance with regional and global isotope curves derived from the marine record, and allow for a refined correlation of the Tertiary succession in the Lower Rhine Basin with the international standard. It is shown that the reconstructed data are largely consistent with the continental climate record for the Northern Hemisphere, as reported by various authors. Discrepancies with previous reconstructions are discussed in detail.

Air pollution data classification by SOM Neural Network

Over the last ten years, Salamanca has been considered among the most polluted cities in México. This paper presents a Self-Organizing Maps (SOM) Neural Network application to classify pollution data and automatize the air pollution level determination for Sulphur Dioxide (SO2) in Salamanca. Meteorological parameters are well known to be important factors contributing to air quality estimation and prediction. In order to observe the behavior and clarify the influence of wind parameters on the SO2 concentrations a SOM Neural Network have been implemented along a year. The main advantages of the SOM is that it allows to integrate data from different sensors and provide readily interpretation results. Especially, it is powerful mapping and classification tool, which others information in an easier way and facilitates the task of establishing an order of priority between the distinguished groups of concentrations depending on their need for further research or remediation actions in subsequent management steps. The results show a significative correlation between pollutant concentrations and some environmental variables.

Caracterización experimental del centelleo troposférico en banda Ka

El presente Proyecto Fin de Grado tiene como objetivo el estudio y caracterización del centelleo troposférico en ausencia de lluvia en la banda Ka de un enlace Tierra-satélite. Para ello se dispondrá de un equipo receptor situado en la Escuela Técnica Superior de Ingenieros de Telecomunicación. Los datos son emitidos desde el satélite EutelSat Hot Bird 13A a una frecuencia de 19,7 GHz. La primera parte del proyecto comienza con las bases teóricas de los distintos fenómenos que afectan a la propagación de un enlace satélite, mencionando los modelos de predicción más importantes. Se ha dado más importancia al apartado perteneciente al centelleo troposférico por ser el tema tratado en este proyecto. El estudio cuenta con datos del satélite durante 7 años comprendidos entre julio de 2006 a junio de 2013. Después del filtrado y el resto del tratamiento adecuado de los datos se han obtenido distintas distribuciones estadísticas que están relacionadas con el centelleo como la varianza. Más tarde se ha comparado la varianza experimental con parámetros meteorológicos obtenidos desde distintas bases de datos. El objetivo de esto ha sido discernir cuál de estos factores afecta en mayor medida a la intensidad de centelleo. Para ello se ha realizado la correlación entre la varianza y varios parámetros meteorológicos: temperatura, humedad relativa, humedad absoluta, índice de refracción húmedo, presión… Además se han realizado medidas de nubosidad en los que se ha clasificado las muestras dependiendo del tipo de nube presente en el cielo. A continuación se ha calculado la varianza mensual media y distribuciones acumuladas de ciertos modelos de predicción de centelleo, comparándolos gráficamente con las curvas experimentales. Estos modelos usan parámetros medidos en superficie por lo que se utilizarán algunos de los parámetros analizados en el capítulo anterior. Por último se expondrán las conclusiones sacadas a lo largo de la realización del proyecto y las posibles líneas de investigación futuras. ABSTRACT. The present Project has as the principal aim the study and characterization of tropospheric scintillation in lack of rain in the band Ka of an Earth-satellite link. It is provided for a receptor equipment located in the ETSIT. The data are broadcasted form the Eutelsat Hot Bird 13A satellite at the frecuency of 19,7 GHz. The beginning of the project starts with the theorical basis of the different phenomenons that affects to the propagation of a satellite link, naming the most important predictions models. The chapter referred to the scintillation has had more importance due to be the main topic in this project. The study deals with satellite data during 7 years between July 2006 to June 2013. After the filter and others treatments of the data, it has been getting different statistics distributions related to scintillation like variance. Later, the experimental variance has been compared with meteorological parameters obtained from different datasets. The purpose has been to decide which factor affects in a greater way to the scintillation intensity. For that it has been doing the correlation between variance and meteorological parameters: temperature, relative humidity, absolute humidity, air refractivity due to water vapour, pressure… Moreover, it has been doing cloudiness measurements in which the samples have been classified in order to the kind of cloud shown in the sky at that moment. Then it has been calculated the monthly averaged variance and the prediction model for cumulative distributions which has been compared with the experimental results. That models uses surface data that they will be uses some meteorological parameters analyzed in previous chapters. Finally it will be shown the conclusions obtained along the realization of the project and the possible ways of future research.

Study of PM10 and PM2.5 levels in three European cities: Analysis of intra and inter urban variations

In the present paper, 1-year PM10 and PM 2.5 data from roadside and urban background monitoring stations in Athens (Greece), Madrid (Spain) and London (UK) are analysed in relation to other air pollutants (NO,NO2,NOx,CO,O3 and SO2)and several meteorological parameters (wind velocity, temperature, relative humidity, precipitation, solar radiation and atmospheric pressure), in order to investigate the sources and factors affecting particulate pollution in large European cities. Principal component and regression analyses are therefore used to quantify the contribution of both combustion and non-combustion sources to the PM10 and PM 2.5 levels observed. The analysis reveals that the EU legislated PM 10 and PM2.5 limit values are frequently breached, forming a potential public health hazard in the areas studied. The seasonal variability patterns of particulates varies among cities and sites, with Athens and Madrid presenting higher PM10 concentrations during the warm period and suggesting the larger relative contribution of secondary and natural particles during hot and dry days. It is estimated that the contribution of non-combustion sources varies substantially among cities, sites and seasons and ranges between 38-67% and 40-62% in London, 26-50% and 20-62% in Athens, and 31-58% and 33-68% in Madrid, for both PM10 and PM 2.5. Higher contributions from non-combustion sources are found at urban background sites in all three cities, whereas in the traffic sites the seasonal differences are smaller. In addition, the non-combustion fraction of both particle metrics is higher during the warm season at all sites. On the whole, the analysis provides evidence of the substantial impact of non-combustion sources on local air quality in all three cities. While vehicular exhaust emissions carry a large part of the risk posed on human health by particle exposure, it is most likely that mitigation measures designed for their reduction will have a major effect only at traffic sites and additional measures will be necessary for the control of background levels. However, efforts in mitigation strategies should always focus on optimal health effects.

Aeropalynology of Australian native arboreal species in Brisbane, Australia

The influence of meteorological parameters on airborne pollen of Australian native arboreal species was investigated in the sub-tropical city of Brisbane, Australia over the five-year period, June 1994–May 1999. Australian native arboreal pollen (ANAP), shed by taxa belonging to the families Cupressaceae, Casuarinaceae and Myrtaceae accounts for 18.4% of the total annual pollen count and is distributed in the atmosphere during the entire year with maximum loads restricted to the months May through November. Daily counts within the range 11–100 grains m–3 occurred over short intervals each year and were recorded on 100 days during the five-year sampling period. Total seasonal ANAP concentrations varied each year, with highest annual values measured for the family Cupressaceae, for which greater seasonal frequencies were shown to be related to pre-seasonal precipitation (r 2 = 0.76, p = 0.05). Seasonal start dates were near consistent for the Cupressaceae and Casuarinaceae. Myrtaceae start dates were variable and established to be directly related to lower average pre-seasonal maximum temperature (r 2 = 0.78, p = 0.04). Associations between daily ANAP loads and weather parameters showed that densities of airborne Cupressaceae and Casuarinaceae pollen were negatively correlated with maximum temperature (p < 0.0001), minimum temperature (p < 0.0001) and precipitation (p < 0.05), whereas associations with daily Myrtaceae pollen counts were not statistically significant. This is the first study to be conducted in Australia that has assessed the relationships between weather parameters and the airborne distribution of pollen emitted by Australian native arboreal species. Pollen shed by Australian native Cupressaceae, Casuarinaceae and Myrtaceae species are considered to be important aeroallergens overseas, however their significance as a sensitising source in Australia remains unclear and requires further investigation.

Climatic effects on the phenology of geophytes

Nowadays, the scientific and social significance of the research of climatic effects has become outstanding. In order to be able to predict the ecological effects of the global climate change, it is necessary to study monitoring databases of the past and explore connections. For the case study mentioned in the title, historical weather data series from the Hungarian Meteorological Service and Szaniszló Priszter’s monitoring data on the phenology of geophytes have been used. These data describe on which days the observed geophytes budded, were blooming and withered. In our research we have found that the classification of the observed years according to phenological events and the classification of those according to the frequency distribution of meteorological parameters show similar patterns, and the one variable group is suitable for explaining the pattern shown by the other one. Furthermore, our important result is that the dates of all three observed phenophases correlate significantly with the average of the daily temperature fluctuation in the given period. The second most often significant parameter is the number of frosty days, this also seem to be determinant for all phenophases. Usual approaches based on the temperature sum and the average temperature don’t seem to be really important in this respect. According to the results of the research, it has turned out that the phenology of geophytes can be well modelled with the linear combination of suitable meteorological parameters

Análise de tendência e caracterização sazonal e interanual da evapotranspiração de referência para o sudoeste da amazônia brasileira: Acre, Brasil

The objective of this research was to investigate monthly climatological, seasonal, annual and interdecadal of the reference evapotranspiration (ETo) in Acre state in order to better understand its spatial and temporal variability and identify possible trends in the region. The study was conducted with data from Rio Branco municipalities, the state capital, Tarauacá and Cruzeiro do Sul considering a 30-year period (1985-2014), from monthly data from weather stations surface of the National Institute of Meteorology. The methodology was held, first, the consistency of meteorological data. Thus, it was made the gap filling in the time series by means of multivariate techniques. Subsequently were performed statistical tests trend (Mann-Kendall) and homogeneity, by Sen's estimator of the magnitude of this trend is estimated, as well as computational algorithms containing parametric and non-parametric tests for two samples to identify from that year the trend has become significant. Finally, analysis of variance technique (ANOVA) was adopted in order to verify whether there were significant differences in average annual evapotranspiration between locations. The indirect method of Penman-Montheith parameterized by FAO was used to calculate the ETo. The results of this work through examination of the descriptive statistics showed that the ETo the annual average was 3.80, 2.92 and 2.86 mm day-1 year, to Rio Branco, Tarauacá and Cruzeiro do Sul, respectively. Featuring quite remarkable seasonal pattern with a minimum in June and a maximum in October, with Rio Branco to town one with the strongest signal (amplitudes) on the other hand, the Southern Cross presented the highest variability among the studied locations. By ANOVA it was found that the average annual statistically different for a significance level of 1% between locations, but the annual average between Cruzeiro do Sul and Tarauacá no statistically significant differences. For the three locations, the 2000s was the one with the highest ETo values associated with warmer waters of the North Atlantic basin and the 80s to lower values, associated with cooler waters of this basin. By analyzing the Mann-kendall and Sen estimator test, there was a trend of increasing the seasonal reference evapotranspiration (fall, winter and spring) on the order of 0.11 mm per decade and that from the years of 1990, 1996 and 2001 became statistically significant to the localities of Cruzeiro do Sul Tarauacá and Rio Branco, respectively. For trend analysis of meteorological parameters was observed positive trend in the 5% level of significance, for average temperature, minimum temperature and solar radiation.

Baseline characteristics of climate, permafrost, and land cover from Samoylov Island, Lena River Delta, Siberia

Samoylov Island is centrally located within the Lena River Delta at 72° N, 126° E and lies within the Siberian zone of continuous permafrost. The landscape on Samoylov Island consists mainly of late Holocene river terraces with polygonal tundra, ponds and lakes, and an active floodplain. The island has been the focus of numerous multidisciplinary studies since 1993, which have focused on climate, land cover, ecology, hydrology, permafrost and limnology. This paper aims to provide a framework for future studies by describing the characteristics of the island's meteorological parameters (temperature, radiation and snow cover), soil temperature, and soil moisture. The land surface characteristics have been described using high resolution aerial images in combination with data from ground-based observations. Of note is that deeper permafrost temperatures have increased between 0.3 to 1.3 °C over the last five years. However, no clear warming of air and active layer temperatures is detected since 1998, though winter air temperatures during recent years have not been as cold as in earlier years.