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The investigation of Ambrosia pollen counts in the air of Sosnowiec was carried out from 1998 to 2010 by means of the volumetric method. The pollen season which was determined by means of the 98% method started at the end of July and the beginning of August and lasted until the end of October. The highest Ambrosia pollen count was recorded in 1999 (222 grains x m-3) and the lowest in 2001 (18 grains x m-3). It was stated that the daily count of pollen grains depended on the wind direction and maximum air temperature. The strongest correlations were found with maximum temperature and with a wind direction from the south east. A high negative correlation coefficient was found between the frequency of inflows of air masses from the west and the annual total of pollen grains and the value of the maximum daily count. The closest sites of Ambrosia L. are at a distance of 25–40 kilometres from the sampling point. Significant correlations with the frequency of inflow of air masses can support the conclusion that Ambrosia pollen grains recorded in Sosnowiec were most probably carried not only from local sources but also, at least in part, from distant places.
The main aim of this work was to determine the changes of meteorological conditions in Poznań, Poland, in the period 1848-2009. The onset of the analyzed period coincides with the launch of conducting instrumental meteorological measurements in Poznań. Professor Smosarski’s analyses and data were taken into account for the examination of the period 1848-1922, while data from NOAA and the Meteorological Yearbooks were applied for the years 1960-2009. It has been concluded that the mean annual temperature for the period 1848-1922 was 0.9°C lower than for 1960-2009, while for 2000-09 it was as much as 1.9ºC higher. It also has been established that a period without ground frost incidences was prolonged and the frost season shortened. Koeppen’s criterion was used to determine the frequency of the conditions leading to landscape stepping.
Together with Alternaria, Cladosporium spores are known to be potent aeroallergens and its concentrations in the air are strongly dependent on meteorological factors. There are many articles from different parts of the world about relationships between Cladosporium spore count and weather parameters. The aim of the study was to review all available publications about Cladosporium spores in the air and compare the results in a short, useful form.
New particle formation and growth were observed at a coastal site (Preila station, Lithuania) during 1997 and 2000–2002. The total amount of data analysed covers 291 one-day periods, 45 (15%) of which were long-term, new particle formation days. Short-term nucleation events (from a few minutes to one hour) and long-term events (from one to eight hours) were identified. The mean particle growth rate, condensation sink and condensable vapour source rate during nucleation events were 3.9 nm h−1, 1.45 × 10−3 cm−3 s−1 and 7.5 × 104 cm−3 s−1 respectively. The average formation rate J10 was 0.4 cm−3 s−1. The nucleation events were accompanied mainly by air masses transported from the north (43%) and north-west (19%). Meteorological parameters and trace gas (O3, SO2, NO2) concentrations were also analysed. It was found that nucleation events are related to high levels of solar radiation.
Alder (Alnus Mill.), as an anemophilous species, produces large quantities of easily dispersed pollen. Annual pollen sums recorded in south-eastern Poland (by the volumetric method – Lanzoni trap) and in the area of the village of Guciów in the Central Roztocze region (pollen deposition in Tauber traps) were compared. The height at which the respective trap sites were located as well as local and regional vegetation and the distance from the nearest alder communities differ in both cases, likewise, the climate of these two regions differ. The analysed pollen data series cover the years 1998-2007 in Roztocze and 2001-2007 in Lublin. Large differences have been noted in Alnus pollen deposition values between particular years. Among them, there were observed years of very high annual sums (2001, 2003, 2006), as well as years of very low pollen deposition values in both regions (2002, 2005, 2007). In the period in question, the mean value of annual Alnus pollen count for Lublin was 5372 alder pollen grains in m3 of air, and in Roztocze 1647 grains per cm2 of area. During the seven-year period of monitoring (2001-2007), very similar trends were noted with respect to airborne alder pollen concentrations at both trap sites. Pollen data have been analysed against meteorological factors affecting alder pollen production and deposition. These are total precipitation and mean monthly air temperature in June, July and August in the year preceding pollen emission and the same weather elements in January and February in the year of pollen emission. In Roztocze a statistically signifi cant negative correlation has been found between Alnus pollen annual sums and total precipitation in August in the year preceding alder pollen emission and in February in the year of pollen emission. In both regions, the Spearman’s correlation coeffi cient does not show any statistically signifi cant values when comparing annual Alnus pollen sums with mean monthly temperatures of both January and February and summer months in the year preceding alder pollen emission.
This paper presents the results of a comparison of basic meteorological parameters in two Arctic fjords situated on the west coast of Spitsbergen, the main island of the Svalbard archipelago. Air temperature, wind speed and direction, humidity and cloud cover from the period 2005 to 2016 are described and compared with previous (from 1975) analyses of meteorological conditions in the investigated region. Such a choice of dates coincides with the time the GAME project measurements were carried out. The main goal of this study was to compare meteorological conditions in two fjords: Hornsund and Kongsfjorden, during the time of rapid climate changes. The results are collated with research results available in literature from previous years. We discovered that in the investigated period the climate of the Hornsund region is more oceanic than in Kongsfjorden. The stable level of the difference in climate elements is manifested and is evident mainly through greater amplitudes in air temperatures in Kongsfjorden, and in stronger winds in Hornsund.
The main characteristics of the Quercus pollination season were studied in 14 different localities of the Iberian Peninsula from 1992-2004. Results show that Quercus flowering season has tended to start earlier in recent years, probably due to the increased temperatures in the pre-flowering period, detected at study sites over the second half of the 20th century. A Growing Degree Days forecasting model was used, together with future meteorological data forecast using the Regional Climate Model developed by the Hadley Meteorological Centre, in order to determine the expected advance in the start of Quercus pollination in future years. At each study site, airborne pollen curves presented a similar pattern in all study years, with different peaks over the season attributable in many cases to the presence of several species. High pollen concentrations were recorded, particularly at Mediterranean sites. This study also proposes forecasting models to predict both daily pollen values and annual pollen emission. All models were externally validated using data for 2001 and 2004, with acceptable results. Finally, the impact of the highly-likely climate change on Iberian Quercus pollen concentration values was studied by applying RCM meteorological data for different future years, 2025, 2050, 2075 and 2099. Results indicate that under a doubled CO2 scenario at the end of the 21st century Quercus pollination season could start on average one month earlier and airborne pollen concentrations will increase by 50% with respect to current levels, with higher values in Mediterranean inland areas.
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