scholarly journals On the aerosol weekly cycle spatiotemporal variability over Europe

2011 ◽  
Vol 11 (10) ◽  
pp. 4611-4632 ◽  
Author(s):  
A. K. Georgoulias ◽  
K. A. Kourtidis
Keyword(s):  
Eastern Europe ◽  
Statistical Significance ◽  
Spatiotemporal Variability ◽  
Spatial And Temporal Variability ◽  
Dust Transport ◽  
Weekly Cycle ◽  
The North ◽  
Synoptic Wind ◽  
Terra Modis ◽  
Weekly Cycles

Abstract. In this work, we focus on the spatial and temporal variability of the aerosol weekly cycle over Europe as these were recorded from TERRA MODIS and AQUA MODIS satellite instruments. Aerosol optical properties retrieved from MODIS TERRA (February 2000–February 2009) and AQUA (July 2002–December 2008) were used to produce an aerosol weekly cycle index. First, the general aerosol optical depth (AOD550 nm) weekly patterns were defined at a 1° × 1° resolution using the satellite-based index and six regions of interest were selected. To remove episodic dust transport events, two different aerosol flags, employing fine mode ratio (FMR550 nm) and AOD550 nm data, were applied diagnostically, showing that the observed weekly cycles over Europe are due to continental aerosols. A second spatial averaging method was then used for the investigation of the weekly variability and the statistical significance of the weekly cycle over each of the previously selected regions. Three major weekly cycle plumes are observed over Europe. A strong positive (higher values during midweek) weekly cycle plume appears over Central Europe, while a strong negative (higher values during weekend) weekly plume appears over the Iberian Peninsula and the North-eastern Europe. The temporal examination of the weekly cycles shows that in some areas there are seasonal differences in the sign of the weekly cycle. The aerosol weekly variability over different regions in Europe was examined in conjunction with the dominating synoptic wind patterns from the NCEP/NCAR reanalysis, showing that the seasonal weekly cycle plumes over regions situated in the eastern Europe and the Mediterranean Sea could be partly attributed to the westerly transport of continental aerosols.

scholarly journals On the aerosol weekly cycle spatiotemporal variability over Europe

2011 ◽  
Vol 11 (1) ◽  
pp. 1385-1428 ◽  
Author(s):  
A. K. Georgoulias ◽  
K. A. Kourtidis
Keyword(s):  
Eastern Europe ◽  
Eastern Mediterranean ◽  
Statistical Significance ◽  
Spatiotemporal Variability ◽  
Spatial And Temporal Variability ◽  
Dust Transport ◽  
Weekly Cycle ◽  
The North ◽  
Synoptic Wind ◽  
Terra Modis

Abstract. In this work, we focus on the spatial and temporal variability of the aerosol weekly cycle over Europe as these were recorded from TERRA MODIS and AQUA MODIS satellite instruments. Aerosol optical properties retrieved from MODIS TERRA (February 2000–February 2009) and AQUA (July 2002–December 2008) were used to produce an aerosol weekly cycle index. First, the general aerosol optical depth (AOD550 nm) weekly patterns were defined at a 1° × 1° resolution using the satellite-based index and six regions of interest were selected. To remove episodic dust transport events, two different aerosol flags, employing fine mode ratio (FMR550 nm) and AOD550 nm data, were applied diagnostically. A second spatial averaging method was then used for the investigation of the weekly variability and the statistical significance of the weekly cycle over each of the previously selected regions. Three major weekly cycle plumes are observed over Europe. A strong positive (higher values during midweek) weekly cycle plume appears over Central Europe, while a strong negative (higher values during weekend) weekly plume appears over the Iberian Peninsula and the North-eastern Europe. A weak but statistically significant negative plume is apparent over the Eastern Mediterranean. The temporal examination of the weekly cycles shows that in some areas there are seasonal differences in the sign of the weekly cycle. The aerosol weekly variability over different regions in Europe was examined in conjunction with the dominating synoptic wind patterns from the NCEP/NCAR reanalysis, showing that the seasonal weekly cycle plumes over regions situated in the eastern Europe and the Mediterranean Sea could be partly attributed to the westerly transport of continental aerosols.

scholarly journals Weekly cycles in precipitation in a polluted region of Europe

2011 ◽  
Vol 11 (1) ◽  
pp. 1777-1801 ◽  
Author(s):  
C. W. Stjern
Keyword(s):  
Statistical Significance ◽  
Precipitation Amount ◽  
Cloud Amount ◽  
Heavy Precipitation ◽  
Potential Effect ◽  
Meteorological Variables ◽  
Precipitation Frequency ◽  
Total Period ◽  
Weekly Cycle ◽  
Weekly Cycles

Abstract. Weekly cycles in aerosol concentration and corresponding cycles in precipitation have been reported over Europe, but results are conflicting. To obtain a large potential effect of aerosols on precipitation we here focus on a highly polluted region on the borders between Germany, Poland and the Czech Republic. Meteorological parameters from 30 surface stations in a mix of urban, rural and remote locations were analyzed for the time period 1983–2008, using three different tests: the Kruskal-Wallis test, a spectral analysis and a comparison of the regular 7-day week to constructed 6- and 8-day weeks. We expect a clear and statistically significant weekly cycle to pass all three tests. Precipitation amount and meteorological variables associated with convective conditions, such as the frequency of heavy precipitation events and observations of rain showers, showed two-peak weekly cycles with maxima on Tuesdays and during weekends. The amplitude of the precipitation cycle increased with longitude towards the more polluted eastern part of the region, but the statistical significance of the cycles did not change correspondingly. The amplitudes of the weekly cycles were in many cases larger for the heavily polluted 1983–1987 period than for the cleaner 2004–2008 as well as the total period, but were equally often largest in the clean period. Moreover, of all the variables, periods and seasons investigated, the weekly cycles were statistically significant only for summertime values of light precipitation frequency and cloud amount, and only by one of the three tests applied. Conclusively, clear weekly cycles in meteorological variables were not found in this polluted region of Europe.

Аquatic and helophytic vegetation of the Yamozero Lake (The Komi Republic)

2011 ◽  
pp. 101-116 ◽  
Author(s):  
B. Yu. Teteryuk
Keyword(s):  
Eastern Europe ◽  
Plant Communities ◽  
Rare Species ◽  
Komi Republic ◽  
European Part ◽  
Regional Level ◽  
North East ◽  
The North ◽  
European Part Of Russia ◽  
Floristic Classification

The results of a sintaxonomical study of plant communities of the Yamozero lake (the North-East of the European part of Russia) are presented. The diversity of the aquatic and helophytic vegetation of the Yamozero lake consists of 16 associations and 2 communities of 6 unions, 4 orders and 2 classes of the floristic classification: Potamogetonetea (7 associations, 2 communities), Phragmito-Magnocaricetea (9 associations). Many of described associations are widely distributed in the Central and the Eastern Europe. Some associations have the boundaries of their ranges. Some communities include 2 rare species of regional level: Isoetes setacea and Sagittaria natans.

scholarly journals Antimicrobial resistance in Neisseria gonorrhoeae isolates and gonorrhoea treatment in the Republic of Belarus, Eastern Europe, 2009–2019

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Aliaksandra Aniskevich ◽  
Iryna Shimanskaya ◽  
Iryna Boiko ◽  
Tatyana Golubovskaya ◽  
Daniel Golparian ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Neisseria Gonorrhoeae ◽  
Eastern Europe ◽  
Treatment Guidelines ◽  
Statistical Significance ◽  
Antimicrobial Treatment ◽  
National Guidelines ◽  
First Line ◽  
Exact Test ◽  
The Republic

Abstract Background Limited antimicrobial resistance (AMR) data for Neisseria gonorrhoeae are available in Eastern Europe. We investigated AMR in N. gonorrhoeae isolates in the Republic of Belarus from 2009 to 2019, antimicrobial treatment recommended nationally, and treatment given to patients with gonorrhoea. Methods N. gonorrhoeae isolates (n = 522) cultured in three regions of Belarus in 2009–2019 were examined. Determination of minimum inhibitory concentrations (MICs) of eight antimicrobials was performed using Etest. Resistance breakpoints from the European Committee on Antimicrobial Susceptibility Testing were applied where available. A Nitrocefin test identified β-lactamase production. Gonorrhoea treatment for 1652 patients was also analysed. Statistical significance was determined by the Z-test, Fisher’s exact test, or Mann-Whitney U test with p-values of < 0.05 indicating significance. Results In total, 27.8% of the N. gonorrhoeae isolates were resistant to tetracycline, 24.7% to ciprofloxacin, 7.0% to benzylpenicillin, 2.7% to cefixime, and 0.8% to azithromycin. No isolates were resistant to ceftriaxone, spectinomycin, or gentamicin. However, 14 (2.7%) isolates had a ceftriaxone MIC of 0.125 mg/L, exactly at the resistance breakpoint (MIC > 0.125 mg/L). Only one (0.2%) isolate, from 2013, produced β-lactamase. From 2009 to 2019, the levels of resistance to ciprofloxacin and tetracycline were relatively high and stable. Resistance to cefixime was not identified before 2013 but peaked at 22.2% in 2017. Only sporadic isolates with resistance to azithromycin were found in 2009 (n = 1), 2012 (n = 1), and 2018–2019 (n = 2). Overall, 862 (52.2%) patients received first-line treatment according to national guidelines (ceftriaxone 1 g). However, 154 (9.3%) patients received a nationally recommended alternative treatment (cefixime 400 mg or ofloxacin 400 mg), and 636 (38.5%) were given non-recommended treatment. Conclusions The gonococcal resistance to ciprofloxacin and tetracycline was high, however, the resistance to azithromycin was low and no resistance to ceftriaxone was identified. Ceftriaxone 1 g can continuously be recommended as empiric first-line gonorrhoea therapy in Belarus. Fluoroquinolones should not be prescribed for treatment if susceptibility has not been confirmed by testing. Timely updating and high compliance with national evidence-based gonorrhoea treatment guidelines based on quality-assured AMR data are imperative. The need for continued, improved and enhanced surveillance of gonococcal AMR in Belarus is evident.

Examining the impacts of Great Lakes’ temperature perturbations on simulated precipitation in the northeastern United States

2021 ◽  
Author(s):  
Janel Hanrahan ◽  
Jessica Langlois ◽  
Lauren Cornell ◽  
Huanping Huang ◽  
Jonathan Winter ◽  
...  
Keyword(s):  
Great Lakes ◽  
New England ◽  
General Circulation ◽  
Lower Boundary ◽  
Historical Period ◽  
Spatial And Temporal Variability ◽  
Lake Surface ◽  
The North ◽  
Surface Temperatures ◽  
Simulated Precipitation

AbstractMost inland water bodies are not resolved by General Circulation Models, requiring that lake surface temperatures be estimated. Given the large spatial and temporal variability of the North American Great Lakes’ surface temperatures, such estimations can introduce errors when used as lower boundary conditions for dynamical downscaling. Lake surface temperatures (LSTs) influence moisture and heat fluxes, thus impacting precipitation within the immediate region and potentially in regions downwind of the lakes. For the present study, the Advanced Research Weather Research and Forecasting Model (WRF-ARW) was used to simulate precipitation over six New England states during a five-year historical period. The model simulation was repeated with perturbed LSTs, ranging from 10°C below to 10°C above baseline values obtained from reanalysis data, to determine whether the inclusion of erroneous LST values impact simulated precipitation and synoptic-scale features. Results show that simulated precipitation in New England is statistically correlated with LST perturbations, but this region falls on a wet-dry line of a larger bimodal distribution. Wetter conditions occur to the north and drier conditions to the south with increasing LSTs, particularly during the warm season. The precipitation differences coincide with large-scale anomalous temperature, pressure, and moisture patterns. Care must therefore be taken to ensure reasonably accurate Great Lakes’ surface temperatures when simulating precipitation, especially in southeastern Canada, Maine, and the Mid-Atlantic region.

scholarly journals Geostatistical analysis of crop yield maps in a long term no tillage system

Bragantia ◽  
2010 ◽  
Vol 69 (suppl) ◽  
pp. 9-18 ◽  
Author(s):  
Osvaldo Guedes Filho ◽  
Sidney Rosa Vieira ◽  
Marcio Koiti Chiba ◽  
Célia Regina Grego
Keyword(s):  
Crop Yield ◽  
Crop Yields ◽  
Spherical Model ◽  
Exponential Model ◽  
Spatial And Temporal Variability ◽  
No Tillage ◽  
Yield Data ◽  
The North ◽  
Tillage System

It is known, for a long time, that crop yields are not uniform at the field. In some places, it is possible to distinguish sites with both low and high yields even within the same area. This work aimed to evaluate the spatial and temporal variability of some crop yields and to identify potential zones for site specific management in an area under no-tillage system for 23 years. Data were analyzed from a 3.42 ha long term experimental area at the Centro Experimental Central of the Instituto Agronômico, located in Campinas, Sao Paulo State, Brazil. The crop yield data evaluated included the following crops: soybean, maize, lablab and triticale, and all of them were cultivated since 1985 and sampled at a regular grid of 302 points. Data were normalized and analyzed using descriptive statistics and geostatistical tools in order to demonstrate and describe the structure of the spatial variability. All crop yields showed high variability. All of them also showed spatial dependence and were fitted to the spherical model, except for the yield of the maize in 1999 productivity which was fitted to the exponential model. The north part of the area presented repeated high values of productivity in some years. There was a positive cross correlation amongst the productivity values, especially for the maize crops.

scholarly journals Specifics of boglands freezing in the north and northwest of the European part of Russia under climate change

2019 ◽  
Vol 59 (2) ◽  
pp. 233-244
Author(s):  
V. I. Batuev ◽  
I. L. Kalyuzhny
Keyword(s):  
Ambient Temperature ◽  
Snow Cover ◽  
Spatial And Temporal Variability ◽  
North West ◽  
The North ◽  
Climatic Period ◽  
European Part Of Russia ◽  
Freezing Depth ◽  
Main Factors ◽  
Cover Thickness

Long-term complex observations covering the period of 1949–2018 made possible to determine the average annual characteristics of the depth of freezing of wetlands in the North and Northwest of the European territory of Russia together with main factors of its formation, and spatial and temporal variability. The main factors that determine the depth of freezing of wetlands are ambient temperature, snow cover thickness, and a degree of watering of the micro landscape (water reserves of the micro landscape). At the initial stage of freezing, the major factor is the ambient temperature, when intensity of the freezing reaches 0.5–0.8 cm/day. As snow falls, the freezing rate becomes smaller, and when the snow cover thickness reaches 25–30 cm the depth amounts to 0.2–0.3 cm/day and smaller. It was found that the spatial variability of the freezing depth decreases from large values of the coefficient of variation (0.3–0.4) at the depth of 20–30 cm to less than 0.1 when the depth exceeds 60 cm. The largest values of the depth are recorded in the North of the Kola Peninsula, where sometimes they reach from 84 to 97 cm with the average values of 48–66. In large hummocky bogs, when the seasonal freezing comes down to 63–65 cm it links with the permafrost layer. On average, swamps of these bogs freeze down to a depth of 68 cm. The average climatic depth of freezing of oligotrophic bogs of the NorthWest is 21–24 cm; in some years, freezing of them reaches 32–40 cm. It has been shown that the relative warming of the climate resulted in decreasing in the depth of freezing of wetlands in the North and North-West of the European territory of Russia. Relative to the previous climatic period, the depth of frost penetration in the northern Ilasskoye bog decreased by 32%, and in north-western Lammin-Suo bog – by 31%.

scholarly journals Investigation of spatiotemporal variability of melt pond fraction and its relationship with sea ice extent during 2000–2017 using a new data

2019 ◽  
Author(s):  
Yifan Ding ◽  
Xiao Cheng ◽  
Jiping Liu ◽  
Fengming Hui ◽  
Zhenzhan Wang
Keyword(s):  
Sea Ice ◽  
Arctic Basin ◽  
Beaufort Sea ◽  
Arctic Sea Ice ◽  
Spatiotemporal Variability ◽  
First Year ◽  
Spatial And Temporal Variability ◽  
Sea Ice Extent ◽  
Melt Pond ◽  
Melt Ponds

Abstract. The accurate knowledge of variations of melt ponds is important for understanding Arctic energy budget due to its albedo-transmittance-melt feedback. In this study, we develop and validate a new method for retrieving melt pond fraction (MPF) from the MODIS surface reflectance. We construct an ensemble-based deep neural network and use in-situ observations of MPF from multi-sources to train the network. The results show that our derived MPF is in good agreement with the observations, and relatively outperforms the MPF retrieved by University of Hamburg. Built on this, we create a new MPF data from 2000 to 2017 (the longest data in our knowledge), and analyze the spatial and temporal variability of MPF. It is found that the MPF has significant increasing trends from late July to early September, which is largely contributed by the MPF over the first-year sea ice. The analysis based on our MPF during 2000–2017 confirms that the integrated MPF to late June does promise to improve the prediction skill of seasonal Arctic sea ice minimum. However, our MPF data shows concentrated significant correlations first appear in a band, extending from the eastern Beaufort Sea, through the central Arctic, to the northern East Siberian and Laptev Seas in early-mid June, and then shifts towards large areas of the Beaufort Sea, Canadian Arctic, the northern Greenland Sea and the central Arctic basin.

scholarly journals Trends in compound extremes of air temperature and precipitation in Eastern Europe

2021 ◽  
Author(s):  
Elena Vyshkvarkova ◽  
Olga Sukhonos
Keyword(s):  
Eastern Europe ◽  
North Atlantic Oscillation ◽  
Air Temperature ◽  
North Atlantic ◽  
Large Scale ◽  
The North ◽  
Temperature And Precipitation ◽  
Atmosphere System ◽  
Daily Data ◽  
The North Atlantic Oscillation

Abstract The spatial distribution of compound extremes of air temperature and precipitation was studied over the territory of Eastern Europe for the period 1950–2018 during winter and spring. Using daily data on air temperature and precipitation, we calculated the frequency and trends of the four indices – cold/dry, cold/wet, warm/dry and warm/wet. Also, we studying the connection between these indices and large-scale processes in the ocean-atmosphere system such as North Atlantic Oscillation, East Atlantic Oscillation and Scandinavian Oscillation. The results have shown that positive trends in the region are typical of the combinations with the temperatures above the 75th percentile, i.e., the warm extremes in winter and spring. Negative trends were obtained for the cold extremes. Statistically significant increase in the number of days with warm extremes was observed in the northern parts of the region in winter and spring. The analysis of the impacts of the large-scale processes in oceans-atmosphere system showed that the North Atlantic Oscillation index has a strong positive and statistically significant correlation with the warm indices of compound extremes in the northern part of Eastern Europe in winter, while the Scandinavian Oscillation shows the opposite picture.

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