scholarly journals Seasonal variability of radiation tide in Gulf of Riga

2020 ◽  
Author(s):  
Vilnis Frishfelds ◽  
Juris Sennikovs ◽  
Uldis Bethers ◽  
Andrejs Timuhins
Keyword(s):  
Water Level ◽  
Atmospheric Pressure ◽  
Dominant Role ◽  
Primary Source ◽  
Sea Breeze ◽  
The Sun ◽  
Yearly Variation ◽  
Main Driver ◽  
Gulf Of Riga

Abstract. Diurnal oscillations of water level in Gulf of Riga are considered. It was found that there is distinct daily pattern of diurnal oscillations in certain seasons. The role of sea breeze, gravitational tides and atmospheric pressure gradient are analysed. The interference of the first two effects provide the dominant role in diurnal oscillations. The effect of gravitational tides is described both with sole tidal forcing and also in real case with atmospheric forcing and stratification. The yearly variation of the declination of the Sun and stratification leads to seasonal intensification of gravitational tides in Gulf of Riga. Correlation between gravitational tide of the Sun with its radiation caused wind effects appears to be main driver of oscillations in Gulf of Riga. Daily variation of wind is primary source of S1 tidal component with a water level maximum at 18:00 UTC in Gulf of Riga. Effect of solar radiation influences also K1 and P1 tidal components which are examined, too.

scholarly journals Quantifying molecular oxygen isotope variations during a Heinrich stadial

2015 ◽  
Vol 11 (11) ◽  
pp. 1527-1551 ◽  
Author(s):  
C. Reutenauer ◽  
A. Landais ◽  
T. Blunier ◽  
C. Bréant ◽  
M. Kageyama ◽  
...  
Keyword(s):  
Isotope Fractionation ◽  
Water Cycle ◽  
Atmospheric Oxygen ◽  
Dominant Role ◽  
Climatic Conditions ◽  
Fractionation Factor ◽  
Last Glacial Period ◽  
Main Driver ◽  
The Last Glacial

Abstract. δ18O of atmospheric oxygen (δ18Oatm) undergoes millennial-scale variations during the last glacial period, and systematically increases during Heinrich stadials (HSs). Changes in δ18Oatm combine variations in biospheric and water cycle processes. The identification of the main driver of the millennial variability in δ18Oatm is thus not straightforward. Here, we quantify the response of δ18Oatm to such millennial events using a freshwater hosing simulation performed under glacial boundary conditions. Our global approach takes into account the latest estimates of isotope fractionation factor for respiratory and photosynthetic processes and make use of atmospheric water isotope and vegetation changes. Our modeling approach allows to reproduce the main observed features of a HS in terms of climatic conditions, vegetation distribution and δ18O of precipitation. We use it to decipher the relative importance of the different processes behind the observed changes in δ18Oatm. The results highlight the dominant role of hydrology on δ18Oatm and confirm that δ18Oatm can be seen as a global integrator of hydrological changes over vegetated areas.

scholarly journals A probable cause of the Yearly variation of magnetic storms and auroræ.

1905 ◽  
Vol 74 (497-506) ◽  
pp. 90-95 ◽  
Author(s):  
Joseph Norman Lockyer ◽  
William J. S. Lockyer
Keyword(s):  
Seasonal Variation ◽  
Atmospheric Pressure ◽  
The Sun ◽  
Magnetic Disturbance ◽  
Yearly Variation ◽  
The Earth ◽  
Yearly Change ◽  
Meteorological Elements ◽  
Considerable Period ◽  
Magnetic Disturbances

The ordinary meteorological elements, such as atmospheric pressure, temperature, etc., have a yearly change satisfactorily explained as due to changes of the position of the earth’s axis in relation to the sun, or, in other words, the variation of the sun’s declination. There are, however, other phenomena, such as magnetic disturbances and auroræ, which have been explained differently. Thus, in regard to this seasonal variation Mr. Ellis has written, “The related physical circumstance is that at the equinoxes, when disturbance is more frequent, the whole surface of the earth comes under the influence of the sun, whilst at the solstices, when magnetic disturbance is less frequent, a portion of the surface remains for a considerable period in shadow.”

A dominant role of oxygen additive on cold atmospheric-pressure He + O2 plasmas

2014 ◽  
Vol 21 (8) ◽  
pp. 083501 ◽  
Author(s):  
Aijun Yang ◽  
Dingxin Liu ◽  
Mingzhe Rong ◽  
Xiaohua Wang ◽  
Michael G. Kong
Keyword(s):  
Atmospheric Pressure ◽  
Dominant Role

scholarly journals Seasonal structure of water stages on lakes in Northern Poland

2018 ◽  
Vol 15 (1) ◽  
pp. 101-110 ◽  
Author(s):  
Katarzyna Plewa ◽  
Dariusz Wrzesiński ◽  
Mariusz Ptak
Keyword(s):  
Water Level ◽  
Annual Cycle ◽  
Dominant Role ◽  
Temporal Structure ◽  
Level Fluctuation ◽  
Frequency Distributions ◽  
Structure Of Water ◽  
Daily Water ◽  
Unsupervised Approach

Abstract The paper presents the characteristics of hydrological periods in an average annual cycle in Polish lakes. The types of period and their sequence determine the regime of water stages in lakes. The article applies the unsupervised approach to analysis of water level fluctuation patterns, where the regime is identified by grouping analytical parameters. Hydrological periods were designated by grouping elementary time units of the hydrological year (pentads) based on the similarity of their parameters, namely water level frequency distributions. The analysis covered daily water stages in 33 lakes in Poland from the period from 1984 to 2012. Five types of hydrological period were designated. The studied lakes differ in the number, type and sequence of hydrological periods in an average annual cycle. Most of the lakes (19 lakes) have a 4-period temporal structure of water stages with the course of water stages in a year characteristic of this geographical zone. No spatial patterns occurred in the location of lakes from particular groups. This suggests the dominant role of local factors in determining the seasonality of water stages.

scholarly journals Quantifying molecular oxygen isotope variations during a Heinrich Stadial

2015 ◽  
Vol 11 (3) ◽  
pp. 2281-2339
Author(s):  
C. Reutenauer ◽  
A. Landais ◽  
T. Blunier ◽  
C. Bréant ◽  
M. Kageyama ◽  
...  
Keyword(s):  
Water Cycle ◽  
Atmospheric Oxygen ◽  
Dominant Role ◽  
Climatic Conditions ◽  
Water Isotopes ◽  
Fractionation Factor ◽  
Last Glacial Period ◽  
Main Driver ◽  
The Last Glacial

Abstract. δ18O of atmospheric oxygen (δ18Oatm) undergoes millennial scale variations during the last glacial period, and systematically increases during Heinrich Stadials (HS). Changes in δ18Oatm combine variations in biospheric and water cycle processes. The identification of the main driver of the millennial variability of δ18Oatm is thus not straightforward. Here, we quantify the response of δ18Oatm to such millennial events using a freshwater hosing simulation (HS_exp) performed under glacial boundary conditions. Our global approach takes into account the latest estimates of isotope fractionation factor for respiratory and photosynthetic processes and make use of atmospheric water isotopes and vegetations changes. Our modeling approach allows to reproduce the main observed features of a HS in terms of climatic conditions, vegetation distribution and δ18O of precipitation. We use it to decipher the relative importance of the different processes behind the observed changes in δ18Oatm. The results highlight the dominant role of hydrology on δ18Oatm and confirm that δ18Oatm can be seen as a global integrator of hydrological changes over vegetated areas.

scholarly journals THE PASSAGE OF THE SUN THROUGH THE MERIDIAN AS AN ASTRONOMICAL FACTOR OF CHANGES IN DEPENDENT VARIABLES IN PHYSICAL SENSORS AND BIOMARKERS

Metaphysics ◽  
2020 ◽  
pp. 35-48
Author(s):  
S. N Shapovalov ◽  
V. I Povazhny
Keyword(s):  
Atmospheric Pressure ◽  
The Arctic ◽  
Meridian Plane ◽  
The Sun ◽  
Near Surface ◽  
Physical Sensors ◽  
Dependent Variables ◽  
The Moment

The results of measurements of the photocurrent of a photoresistor installed in the focal plane of a telescope-reflector at st. Novolazarevskaya (Antarctica) in order to register the “culmination” signal from the passage of the Sun through the meridian (culmination). As a result of photocurrent measurements conducted on 03.02.2013 and 04.02.2013 in the midday interval from 11h00m to 11h50m (UT), the “response” (effect) of the photocurrent to the Sun's influence in the position of the meridian plane (culmination) is established. The results of the study of the reaction of the main human biomarkers (in vivo) to the culmination of the Sun, obtained in the analysis of observational data for the period from 20.01.2017, are also presented for 18.04.2017 at the Arctic station “Ice Base Cape Baranova” (arch. Northern Land). Conclusions are made about the sensitivity of the arterial systolic (upper) to the moment of climax and its dependence on the near-surface atmospheric pressure at the frequency of "five-minute" fluctuations (r ~ 0,8). In conclusion, the role of the culmination of the Sun as an astronomical factor in the processes of living and inanimate nature is noted.

scholarly journals Aerosol composition, sources and processes during wintertime in Beijing, China

2013 ◽  
Vol 13 (9) ◽  
pp. 4577-4592 ◽  
Author(s):  
Y. L. Sun ◽  
Z. F. Wang ◽  
P. Q. Fu ◽  
T. Yang ◽  
Q. Jiang ◽  
...  
Keyword(s):  
Environmental Concern ◽  
Dominant Role ◽  
Primary Source ◽  
High Concentration ◽  
Aerosol Composition ◽  
Diurnal Cycles ◽  
Secondary Factor ◽  
Beijing China ◽  
Pollution Episodes

Abstract. Air pollution is a major environmental concern during all seasons in the megacity of Beijing, China. Here we present the results from a winter study that was conducted from 21 November 2011 to 20 January 2012 with an Aerodyne Aerosol Chemical Speciation Monitor (ACSM) and various collocated instruments. The non-refractory submicron aerosol (NR-PM1) species vary dramatically with clean periods and pollution episodes alternating frequently. Compared to summer, wintertime submicron aerosols show much enhanced organics and chloride, which on average account for 52% and 5%, respectively, of the total NR-PM1 mass. All NR-PM1 species show quite different diurnal behaviors between summer and winter. For example, the wintertime nitrate presents a gradual increase during daytime and correlates well with secondary organic aerosol (OA), indicating a dominant role of photochemical production over gas–particle partitioning. Positive matrix factorization was performed on ACSM OA mass spectra, and identified three primary OA (POA) factors, i.e., hydrocarbon-like OA (HOA), cooking OA (COA), and coal combustion OA (CCOA), and one secondary factor, i.e., oxygenated OA (OOA). The POA dominates OA during wintertime, contributing 69%, with the other 31% being SOA. Further, all POA components show pronounced diurnal cycles with the highest concentrations occurring at nighttime. CCOA is the largest primary source during the heating season, on average accounting for 33% of OA and 17% of NR-PM1. CCOA also plays a significant role in chemically resolved particulate matter (PM) pollution as its mass contribution increases linearly as a function of NR-PM1 mass loadings. The SOA, however, presents a reverse trend, which might indicate the limited SOA formation during high PM pollution episodes in winter. The effects of meteorology on PM pollution and aerosol processing were also explored. In particular, the sulfate mass is largely enhanced during periods with high humidity because of fog processing of high concentration of precursor SO2. In addition, the increased traffic-related HOA emission at low temperature is also highlighted.

Microstructure and reactivity of small metal particles: The role of Ce additives

1992 ◽  
Vol 50 (1) ◽  
pp. 318-319
Author(s):  
L.D. Schmidt ◽  
K. R. Krause ◽  
J. M. Schwartz ◽  
X. Chu
Keyword(s):  
Atmospheric Pressure ◽  
Noble Metals ◽  
Mixed Oxides ◽  
Catalytic Properties ◽  
Chemical Shifts ◽  
Catalytic Converter ◽  
Structural Evolution ◽  
Single Particles ◽  
Small Metal Particles

The evolution of microstructures of 10- to 100-Å diameter particles of Rh and Pt on SiO2 and Al2O3 following treatment in reducing, oxidizing, and reacting conditions have been characterized by TEM. We are able to transfer particles repeatedly between microscope and a reactor furnace so that the structural evolution of single particles can be examined following treatments in gases at atmospheric pressure. We are especially interested in the role of Ce additives on noble metals such as Pt and Rh. These systems are crucial in the automotive catalytic converter, and rare earths can significantly modify catalytic properties in many reactions. In particular, we are concerned with the oxidation state of Ce and its role in formation of mixed oxides with metals or with the support. For this we employ EELS in TEM, a technique uniquely suited to detect chemical shifts with ∼30Å resolution.

Chronic Pain: Fundamental Scientific Considerations, Specifically for Legal Claims

2013 ◽  
Vol 18 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Robert J. Barth
Keyword(s):  
Health Outcomes ◽  
Pain Perception ◽  
Driving Forces ◽  
Psychological Treatment ◽  
Dominant Role ◽  
Meta Analysis ◽  
General Medicine ◽  
Pain Syndrome ◽  
Problematic Relationship

Abstract Scientific findings have indicated that psychological and social factors are the driving forces behind most chronic benign pain presentations, especially in a claim context, and are relevant to at least three of the AMA Guides publications: AMA Guides to Evaluation of Disease and Injury Causation, AMA Guides to Work Ability and Return to Work, and AMA Guides to the Evaluation of Permanent Impairment. The author reviews and summarizes studies that have identified the dominant role of financial, psychological, and other non–general medicine factors in patients who report low back pain. For example, one meta-analysis found that compensation results in an increase in pain perception and a reduction in the ability to benefit from medical and psychological treatment. Other studies have found a correlation between the level of compensation and health outcomes (greater compensation is associated with worse outcomes), and legal systems that discourage compensation for pain produce better health outcomes. One study found that, among persons with carpal tunnel syndrome, claimants had worse outcomes than nonclaimants despite receiving more treatment; another examined the problematic relationship between complex regional pain syndrome (CRPS) and compensation and found that cases of CRPS are dominated by legal claims, a disparity that highlights the dominant role of compensation. Workers’ compensation claimants are almost never evaluated for personality disorders or mental illness. The article concludes with recommendations that evaluators can consider in individual cases.

The role of science in the study of and response to space threats

2019 ◽  
Vol 89 (8) ◽  
pp. 777-799
Author(s):  
B. M. Shustov
Keyword(s):  
Comparative Analysis ◽  
20Th Century ◽  
21St Century ◽  
Space Debris ◽  
The Sun ◽  
National Program ◽  
Biological Hazard ◽  
Academy Of Sciences ◽  
Space Activities

During the second half of the 20th century and the beginning of the 21st century, space hazards multiplied, the most urgent of which is space debris. Professionals working in space are exposed to this hazard daily and are aware of it as a problem. Furthermore, increasing attention is being paid to the unpredictable behavior of the Sun, which produces the so-called space weather. The asteroid-comet hazard is considered as potentially having the most catastrophic consequences. No manifestations of biological hazard have yet been observed, although as space activities develop, it is becoming increasingly important. The appropriate time scale for astrophysical hazards is many millions of years, so from a practical perspective, they have no importance. This article briefly describes the main types of space hazards. The author analyzes the results of research and practical work in the field, both worldwide and specifically in Russia. Comparative analysis leads to the clear conclusion that a national program must be developed for the study of space hazards and to respond to space threats. This article is based on a report made by the author at the meeting of the Presidium of the Russian Academy of Sciences (RAS) on January 15, 2019.

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