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Riigikaitse ja avalik arvamus 2015-10
No full textAndmetele ligipääsu taotlemiseks palun võtta ühendust TÜ ühiskonnateaduste instituudi empiirilise sotsioloogia professor Kairi Kasearuga aadressil [email protected] ja analüütik Elen Linaga aadressil [email protected] Kaitseministeeriumi tellitud regulaaruuringu "Riigikaitse ja avalik arvamus" andmestik 2015-1
Vertical profiles of atmospheric variables based on tethersonde soundings from Ny-Ålesund
No full textSoundings were carried out on daily basis by using Vaisala tethersonde system DigiCORA TT12 with maximum altitude of 2000 m. The instrumentation consisted of 7 m3 helium filled balloon for lifting sondes, an electrical winch, three sondes suspended on the tether line below the balloon at approximately 20 m vertical intervals, and a ground station. Limited by the wind speed, however, soundings were not possible to perform every day.
Each profile in dataset includes ascending and descending profiles of variables. Dataset presents raw data where no averaging over the sondes and heights is done. Yet, data is checked manually for errors. Some distinct obviously erroneous signals and spike values were removed from the data. More about the methods is described in ReadMe text file.The melt of snow and sea ice in Svalbard and its fjords is strongly controlled by the radiative and turbulent surface fluxes. The fluxes depend, among others, on the structure of and processes in the ABL. Over a complex topography, such as Svalbard mountains and fjords, the state of the ABL is not well known. It is affected by the synoptic-scale flow conditions, which vary between cases of advection of warm, marine air masses from open ocean and cold-air outbreaks from the north or east.
Data of vertical profiles of atmospheric variables were collected as a part of the project "Atmospheric boundary layer and its interaction with snow and sea ice in Svalbard fjords". The principal objective of the project was to better understand and quantify the processes in the atmospheric boundary layer (ABL) over complex topography in Svalbard and their interaction with the snow and sea ice surface.
Soundings archive consists 17 high-resolution vertical profiles of the measured atmospheric characteristics (air temperature, relative humidity, wind speed and direction, and air pressure) acquired from the tethersonde soundings campaign in Ny-Ålesund (Svalbard archipelago) between 21 March and 2 April in 2009.European Centre for Arctic Environmental Research (ARCFAC).
Target financed project SF0180049s09 of the Ministry of Education and Research of the Republic of Estonia.
6th EU Framework Programme project DAMOCLES (Grant 18509)
Nanoion 2010-11
No full textThe dataset provides measurements of the mobility and size distributions of charged molecular clusters and finest aerosol particles naturally found in atmospheric air. The genesis and subsequent evolution of nanoparticles is a key to understanding the formation of atmospheric aerosols, which is an essential factor of the Earth's climate. The particles are classified according to their size and electric mobility. Immediately was determined the particle electric mobility while the size was calculated as the mobility equivalent diameter of the nanoparticle. In atmospheric electricity, the charged molecules and clusters up to 1.6 nm in diameter are called small air ions and the finest aerosol particles of size between 1.6 and 7.4 nm are called intermediate air ions. The positive and negative small and intermediate air ions were routinely measured at Tartu, Estonia (58.373 N, 26.727 E, 70 m a.s.l.). The dataset includes results of a measurement campaign started at 1 April 2010 and finished at 8 November 2011. The full mobility range was logarithmically uniformly divided into 16 fractions. 10 of these fractions include the intermediate ions and 6 include the small ions. The dataset presents unique information about nanoparticles up to 7.4 nm in diameter in the atmospheric air. The author acknowledges Kaupo Komsaare for taking care of the instrument, Sander Mirme for presenting the meteorological data, and Urmas Hõrrak for general arrangements and discussions.
The dataset contains files:
Ø nanoion2010_11data.pdf – information about the origin of data and structure of the data files,
Ø nanoion2010_11instrument.pdf – description of the instrument SIGMA used for measuring nanoparticle mobility and size distribution,
Ø nanoion2010_11hours.xls – hourly averages of nanoparticle distribution according to their mobility and size, complemented with meteorological data,
Ø nanoion2010_11records.xls – five minute averages of nanoparticle distribution according to mobility and size,
Ø nanoion2010_11diagrams.ppt – contour plots of nanoparticle size distribution evolution during 147 days,
Ø nanoion2010_11.zip – compressed package of files for download and offline use on a personal computer
Hyytiala08_10aerosol
No full textThe dataset Hyytiala08_10aerosol contains results of routine measurements of atmospheric aerosols carried on in a well equipped boreal research station during 3 years. The particle size range from 3 nm to 15μm is split into 60 fractions and the records of distribution function are presented for 21682 hours of measurements. The dataset provides scientists with a tool for exploring the structure and dynamics of atmospheric aerosol size distribution. Additionally, it can serve as a basis for data analysis exercises for students in field of environmental sciences.
The dataset includes three files:
Data_Hyytiala08_10aerosol.xls – a spreadsheet, which contains 60 columns of values of the particle size distribution function and 30 columns of complementary variables.
Description_Hyytiala08_10aerosol.pdf – detailed description of origin and structure the data. Additionally includes sample diagrams, which illustrate the data and may provoke new ideas for studies on atmospheric aerosol.
Package_Hyytiala08_10aerosol.zip – a compressed package, which contains both the data file and the description file. The package is to be downloaded to a personal computer, unzipped and used offline
Riigikaitse ja avalik arvamus 2015-03
No full textAndmetele ligipääsu taotlemiseks palun võtta ühendust TÜ ühiskonnateaduste instituudi empiirilise sotsioloogia professor Kairi Kasearuga aadressil [email protected] ja analüütik Elen Linaga aadressil [email protected] Kaitseministeeriumi tellitud regulaaruuringu "Riigikaitse ja avalik arvamus" andmestik 2015-0
Vertical profiles of atmospheric variables based on tethersonde soundings from Hornsund
No full textA tethersonde system by Vaisala (DigiCORA TT12) was applied to measure high-resolution vertical profiles of atmospheric variables (air temperature, relative humidity, wind speed and direction, and air pressure) up to 2000 meters. The instrumentation consisted of 7 m3 helium filled balloon for lifting sondes, an electrical winch, two sondes suspended on the tether line below the balloon at approximately 10 m vertical intervals, and a ground station.
Sondes were ascended as high as possible at every measurement. Depending on the cloud conditions, wind speed, and the buoyancy of the balloon, the height of the soundings varied, but was in average 1212 m. Each profile includes ascending and descending of the sonde. Sampling interval of the sondes was in average 5-6 seconds.
Length of the soundings was variable depending of the weather conditions. Tethersonde system is wind sensitive and there were some temporal gaps in planned measurements when soundings could not be performed due to the strong winds and heavy snowfall.
Since 17th of October soundings were done in collaboration with University Centre in Svalbard. Measurements then were simultaneously carried out in Adventdalen fjord. These synchronized atmosphere soundings were aimed to study ABL at different places in a same time.
Data is checked manually for errors but no averaging over the sondes and heights is done. Some distinct obviously erroneous signals and spike values were removed from the data. More about the methods is described in ReadMe text file.Arctic fjords are usually surrounded by a complex orography of mountains, valleys and glaciers, which complicates the dynamics of the air flow. Between different fjords in Svalbard temperature and wind regime can vary largely in space. Due to the combined effects of the complex orography and thermal heterogeneity of the fjord surface, the dynamic and thermodynamic processes affecting the state of the ABL are complex. Although several studies have addressed boundary-layer and mesoscale processes in the Svalbard region, there is still lack of thorough observational analysis on temperature and humidity inversions and low-level jets, based on an extensive dataset. The major challenges still remain in understanding several features in the stable boundary layer (SBL).
The fieldwork campaign in Hornsund (Svalbard archipelago) was part of the project focusing on a vertical structure of the atmospheric boundary layer (ABL) and its possible changes in the Polar regions. Our study is motivated to better understand the ABL structure over fjords. There is need to improve numerical weather prediction and climate models and to improve the forecasting capabilities on near-surface weather. Gathering more in situ data would allow us to rise quality of analyses of ABL characteristics and aim better on these goals.
Dataset consist 52 vertical profiles from tethersonde soundings. These soundings were carried out on a regular basis in Polish Polar Station in Hornsund between 7 October and 1 November 2014.SA Archimedes: Climate and environmental changes in polar regions related to global changes and their influence on climate variability in the northern Europe (SLOOM12073T
Riigikaitse ja avalik arvamus 2014-03
No full textAndmetele ligipääsu taotlemiseks palun võtta ühendust TÜ ühiskonnateaduste instituudi empiirilise sotsioloogia professor Kairi Kasearuga aadressil [email protected] ja analüütik Elen Linaga aadressil [email protected] Kaitseministeeriumi tellitud regulaaruuringu "Riigikaitse ja avalik arvamus" andmestik 2014-0
Talet Makri on Rivers in Meghalaya
No full textTalet Makri, tradition bearer, sings a vernacular folksong on the topics of rivers and wate
