scholarly journals Severity of the present-day climate in the Polar regions of Siberia

2019 ◽  
Vol 59 (2) ◽  
pp. 258-266 ◽  
Author(s):  
E. V. Maksyutova ◽  
L. B. Bashalkhanova
Keyword(s):  
Local Time ◽  
Air Temperature ◽  
Temperature Rise ◽  
Thermal State ◽  
Severity Index ◽  
Space Time ◽  
Climatic Conditions ◽  
Polar Regions ◽  
The West ◽  
Time Dynamics

Over the period 1981–2015 severe climatic conditions on the North of Siberia (area within 66–162° E above the Polar Circle) were characterized by significant space-time variations of air temperature at the cold period of the year. This conclusion is made on the basis of analysis of observations made about 13 hour of local time. Positive changes in the mean seasonal air temperature were observed here in October–April. The largest rates of air temperature rise with a pronounced gradient to the West were noted in high latitudes, i.e. in Arctic glacial and polar desert landscapes. The change in weather severity which is one of characteristics of the climate discomfort was analyzed by means of the Arnoldi index (TA). This index reflects the combined effect of negative temperatures and stiff wind on the thermal state of the open surface of the human body. Together with the space-time dynamics of the actual TA values, important values of TA are its threshold values (more than 30 and more than 45 units) which determine a degree of discomfort. Duration of these periods, limiting a possibility of a person's stay in the open air, is also extremely important as well. In recent decades (1981–2015), the spatial differentiation of the number of days (from 80 to 160) limiting the human’s stay in the open air reflects in the main fluctuations of the air temperature and wind regime in polar landscapes. Slight warming (a rise of the air temperature) and small wind speed variability during the period from October to April in 1981–2015 resulted in a certain decrease in the index of weather severity in relation to the period 1966–1980, since the last one did not did not go beyond limit of the interannual variability. Despite the stable increase in the air temperature in 1981–2015, no tendency to reduction of the number of days limiting human’s stay in the open air was noted. The duration of this period for 1981–2015 is similar to that observed in 1936–1964, and we believe that this is suggestive of manifestation of the cyclicity of atmospheric processes and is agreed with a gradual decrease in the rate of the temperature rise. In the last period duration of the period limiting human stay in the open air in the considered area remains high and ranges from 3.5 (to the west of 80° E) to 5 months on islands and capes of the region. So, as is demonstrated by the above example of space-time dynamics of the weather severity index at the time about 13 hours of local time, no decrease in the level of discomfort in polar Siberia is found.

scholarly journals Space-time variability of the Roncador river basin in the change of land use and cover and its correlation with climatic variables

2019 ◽  
Vol 35 (4) ◽  
Author(s):  
Raquel de Oliveira Santos ◽  
Rafael Coll Delgado ◽  
Marcos Gervasio Pereira ◽  
Leonardo Paula de Souza ◽  
Paulo Eduardo Teodoro ◽  
...  
Keyword(s):  
River Basin ◽  
Air Temperature ◽  
Vegetation Index ◽  
Space Time ◽  
Google Earth ◽  
Climatic Variables ◽  
Computer Application ◽  
Coefficient Of Determination ◽  
Native Forest ◽  
Time Dynamics

The objective of this study was to evaluate the space-time dynamics of the soil use and occupation of the Rio Roncador river basin between 1985 and 2010. The scenes were classified by two methods (partially unsupervised - K-Means and supervised - Maximum likelihood), the Thematic Mapper sensor products on the LANDSAT 5 orbital platform were used for both images of a 25-year time series (1985 to 2000). In order to measure the accuracy of the field the computer application Google Earth was used, in which nine classes (urban area, agricultural area, pasture, exposed soil, native forest, secondary vegetation, mangrove, altitude field and water) were collected. A multiple linear regression was performed, correlating the Normalized Difference Vegetation Index - mean NDVI (dependent variable) with the independent climatic variables (global solar radiation - MJm-2day-1, average air temperature - °C, relative humidity -%, evapotranspiration - mm d-1, and rain - mm). According to the general classification by Kappa parameter of the images for 2005 and 2010, they were identified as very good (68% and 74%). These results confirm that the Roncador River Basin is undergoing transformation in its landscape, with an average reduction of -49% in native vegetation areas due to the increase in urban areas (25%) and agriculture (31%). The statistical analysis showed that rainfall and air temperature were the only variables that presented significant sigma (0.04) and (0.02). The obtained coefficient of determination indicated that 47% of the variations of the "vegetation index" are explained by the environmental variables.  

Dependence of Air Temperature, Enclosing Structures and Floor in Livestock Premises

2020 ◽  
pp. 50-54
Author(s):  
Aleksey V. Kuz’michev ◽  
Dmitriy A. Tikhomirov
Keyword(s):  
Surface Temperature ◽  
Thermal Insulation ◽  
Air Temperature ◽  
Thermal State ◽  
Climatic Conditions ◽  
Research Purpose ◽  
Thermal Mode ◽  
Limit Values ◽  
Floor Surface ◽  
Floor Temperature

The comfort of the animals is determined by temperature factors, such as air temperature, radiation temperature of the room and floor. For a reasonable technical decision on the choice of power equipment for creating normal conditions for keeping animals, it is necessary to identify possible variations in the temperature parameters of the environment in the animal housing zone. (Research purpose) The research purpose is in considering the models for calculating heat losses to the ground and determining the limit values for changes in floor temperature in areas where animals are housed. (Materials and methods) The article presents the studied physical model of heat transfer. The article presents the boundaries of changes in floor temperature in the areas of animal keeping in livestock premises. (Results and discussion) The thermal mode of a room depends on the climatic conditions that affect the state of the internal environment through the enclosing structures and ventilation, and technical factors, as the building structure, the size and thermal insulation properties of fences, heating. There are many types of designs of livestock premises for various purposes, and therefore it is necessary to conduct an additional assessment of the floor surface temperature. The engineering method of calculating the floor surface temperature determines the temperature in the room at known current values, and allows to predict the thermal state of the floor surfaces in the locations of animals. (Conclusions) Meteorological conditions and construction of buildings, thermal insulation properties of fences, thermal characteristics of the soil, floor insulation affect the temperature mode in the room. For buildings with lightweight structures of walls and ceilings, the surface temperature affects the thermal mode of floors in the room.

scholarly journals Seasonal Climate Impacts on Vocal Activity in Two Neotropical Nonpasserines

Diversity ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 319
Author(s):  
Cristian Pérez-Granados ◽  
Karl-L. Schuchmann
Keyword(s):  
Air Temperature ◽  
Daily Rainfall ◽  
Climatic Conditions ◽  
Dry Season ◽  
Climate Impacts ◽  
Calling Behavior ◽  
Wet Season ◽  
Focal Species ◽  
Calling Activity ◽  
Vocal Activity

Climatic conditions represent one of the main constraints that influence avian calling behavior. Here, we monitored the daily calling activity of the Undulated Tinamou (Crypturellus undulatus) and the Chaco Chachalaca (Ortalis canicollis) during the dry and wet seasons in the Brazilian Pantanal. We aimed to assess the effects of climate predictors on the vocal activity of these focal species and evaluate whether these effects may vary among seasons. Air temperature was positively associated with the daily calling activity of both species during the dry season. However, the vocal activity of both species was unrelated to air temperature during the wet season, when higher temperatures occur. Daily rainfall was positively related to the daily calling activity of both species during the dry season, when rainfall events are scarce and seem to act as a trigger for breeding phenology of the focal species. Nonetheless, air temperature was negatively associated with the daily calling activity of the Undulated Tinamou during the wet season, when rainfall was abundant. This study improves our understanding of the vocal behavior of tropical birds and their relationships with climate, but further research is needed to elucidate the mechanisms behind the associations found in our study.

Modeling soil temperature using air temperature features in diverse climatic conditions with complementary machine learning models

2021 ◽  
Vol 185 ◽  
pp. 106158
Author(s):  
Maryam Bayatvarkeshi ◽  
Suraj Kumar Bhagat ◽  
Kourosh Mohammadi ◽  
Ozgur Kisi ◽  
M. Farahani ◽  
...  
Keyword(s):  
Machine Learning ◽  
Soil Temperature ◽  
Air Temperature ◽  
Climatic Conditions ◽  
Learning Models ◽  
Machine Learning Models

scholarly journals Changes in Air Temperature and Snow Cover in Winter in Poland

Atmosphere ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 68
Author(s):  
Arkadiusz M. Tomczyk ◽  
Ewa Bednorz ◽  
Katarzyna Szyga-Pluta
Keyword(s):  
Snow Cover ◽  
Air Temperature ◽  
Winter Season ◽  
Primary Objective ◽  
Climatic Conditions ◽  
Cover Depth ◽  
North Eastern ◽  
Northern Regions ◽  
Maximum Air Temperature ◽  
Snow Cover Depth

The primary objective of the paper was to characterize the climatic conditions in the winter season in Poland in the years 1966/67–2019/20. The study was based on daily values of minimum (Tmin) and maximum air temperature (Tmax), and daily values of snow cover depth. The study showed an increase in both Tmin and Tmax in winter. The most intensive changes were recorded in north-eastern and northern regions. The coldest winters were recorded in the first half of the analyzed multiannual period, exceptionally cold being winters 1969/70 and 1984/85. The warmest winters occurred in the second half of the analyzed period and among seasons with the highest mean Tmax, particularly winters 2019/20 and 1989/90 stood out. In the study period, a decrease in snow cover depth statistically significant in the majority of stations in Poland was determined, as well as its variability both within the winter season and multiannual.

Fitting partial differential equations to space-time dynamics

1999 ◽  
Vol 59 (1) ◽  
pp. 337-342 ◽  
Author(s):  
Markus Bär ◽  
Rainer Hegger ◽  
Holger Kantz
Keyword(s):  
Partial Differential Equations ◽  
Differential Equations ◽  
Space Time ◽  
Partial Differential ◽  
Time Dynamics

Main engine of transport ship inlet air cooling by ejector chiller

2020 ◽  
Vol 5 (3) ◽  
pp. 33-48
Author(s):  
Roman M. Radchenko1 ◽  
◽  
Dariusz Mikielewicz2 ◽  
Mykola I. Radchenko1 ◽  
Victoria S. Kornienko1 ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Air Temperature ◽  
Temperature Drop ◽  
Climatic Conditions ◽  
Air Cooling ◽  
Slow Speed ◽  
Exhaust Gases ◽  
Transport Ship ◽  
Main Engine

The efficiency of cooling the air at the inlet of marine slow speed diesel engine turbocharger by ejector chiller utilizing the heat of exhaust gases and scavenge air were analyzed. The values of air temperature drop at the inlet of engine turbocharger and corresponding decrease in fuel consumption of the engine at varying climatic conditions on the route line Odesa-Yokogama- Odesa were evaluated.

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