scholarly journals Dynamical evolution of vertical profile of rain structures observed using ground-based radar over a tropical station

Heliyon ◽  
2021 ◽  
Vol 7 (4) ◽  
pp. e06888
Author(s):  
J.S. Ojo ◽  
D.B. Akoma ◽  
E.O. Olurotimi
Keyword(s):  
Vertical Profile ◽  
Dynamical Evolution ◽  
Tropical Station

Statistical results on discovered near-Earth asteroids

1999 ◽  
Vol 173 ◽  
pp. 81-86
Author(s):  
S. Berinde
Keyword(s):  
Dynamical Evolution ◽  
Minor Planet ◽  
Orbital Elements ◽  
The Earth ◽  
Near Earth Asteroids ◽  
Statistical Results

AbstractThe first part of this paper gives a recent overview (until July 1st, 1998) of the Near-Earth Asteroids (NEAs) database stored at Minor Planet Center. Some statistical interpretations point out strong observational biases in the population of discovered NEAs, due to the preferential discoveries, depending on the objects’ distances and sizes. It is known that many newly discovered NEAs have no accurately determinated orbits because of the lack of observations. Consequently, it is hard to speak about future encounters and collisions with the Earth in terms of mutual distances between bodies. Because the dynamical evolution of asteroids’ orbits is less sensitive to the improvement of their orbital elements, we introduced a new subclass of NEAs named Earth-encounter asteroids in order to describe more reliably the potentially dangerous bodies as impactors with the Earth. So, we pay attention at those asteroids having an encounter between their orbits and that of the Earth within 100 years, trying to classify these encounters.

From the Oort cloud to Halley-type comets

1999 ◽  
Vol 173 ◽  
pp. 327-338 ◽  
Author(s):  
J.A. Fernández ◽  
T. Gallardo
Keyword(s):  
Total Population ◽  
Complex Function ◽  
Dynamical Evolution ◽  
Oort Cloud ◽  
Capture Process ◽  
Influx Rate ◽  
Short Period ◽  
Dynamical Properties ◽  
Orbital Periods ◽  
Probability Of Capture

AbstractThe Oort cloud probably is the source of Halley-type (HT) comets and perhaps of some Jupiter-family (JF) comets. The process of capture of Oort cloud comets into HT comets by planetary perturbations and its efficiency are very important problems in comet ary dynamics. A small fraction of comets coming from the Oort cloud − of about 10−2− are found to become HT comets (orbital periods < 200 yr). The steady-state population of HT comets is a complex function of the influx rate of new comets, the probability of capture and their physical lifetimes. From the discovery rate of active HT comets, their total population can be estimated to be of a few hundreds for perihelion distancesq <2 AU. Randomly-oriented LP comets captured into short-period orbits (orbital periods < 20 yr) show dynamical properties that do not match the observed properties of JF comets, in particular the distribution of their orbital inclinations, so Oort cloud comets can be ruled out as a suitable source for most JF comets. The scope of this presentation is to review the capture process of new comets into HT and short-period orbits, including the possibility that some of them may become sungrazers during their dynamical evolution.

Exploring Coronal Structures with SOHO

2000 ◽  
Vol 179 ◽  
pp. 403-406
Author(s):  
M. Karovska ◽  
B. Wood ◽  
J. Chen ◽  
J. Cook ◽  
R. Howard
Keyword(s):  
Solar Corona ◽  
Image Enhancement ◽  
Coronal Mass Ejections ◽  
Dynamical Evolution ◽  
Small Scale ◽  
Low Contrast ◽  
Contrast Structures ◽  
Scale Structures ◽  
Small Scale Structures ◽  
Coronal Structures

AbstractWe applied advanced image enhancement techniques to explore in detail the characteristics of the small-scale structures and/or the low contrast structures in several Coronal Mass Ejections (CMEs) observed by SOHO. We highlight here the results from our studies of the morphology and dynamical evolution of CME structures in the solar corona using two instruments on board SOHO: LASCO and EIT.

Evolution of collisional systems

1984 ◽  
Vol 75 ◽  
pp. 361-362
Author(s):  
André Brahic
Keyword(s):  
Gravitational Field ◽  
Dynamical Evolution ◽  
Oblate Planet

AbstractThe dynamical evolution of planetary discs in the gravitational field of an oblate planet and a satellite is numerically simulated.

The Jovian ring

1984 ◽  
Vol 75 ◽  
pp. 203-209
Author(s):  
Joseph A. Burns
Keyword(s):  
Equatorial Plane ◽  
Charged Particles ◽  
Dynamical Evolution ◽  
Main Band ◽  
Small Grains ◽  
Three Components

ABSTRACTLying in Jupiter's equatorial plane is a diaphanous ring having little substructure within its three components (main band, faint disk, and halo). Micron-sized grains account for much of the visible ring, but particles of centimeter sizes and larger must also be present to absorb charged particles. Since dynamical evolution times and survival life times are quite short (≲102-3yr) for small grains, the Jovian ring is being continually replenished; probably most of the visible ring is generated by micrometeoroids colliding into unseen parent bodies that reside in the main band.

Conception of vadose zone research in the area of Goczałkowice reservoir.

2013 ◽  
Vol 2 (1) ◽  
pp. 22-26
Author(s):  
Joanna Czekaj ◽  
Kamil Trepka
Keyword(s):  
Vadose Zone ◽  
Unsaturated Zone ◽  
Vertical Profile ◽  
Structural Model ◽  
Historical Data ◽  
Integrated System ◽  
Nitrate Transport ◽  
Strategic Research ◽  
Research Site ◽  
Observation Wells

Abstract Goczałkowice reservoir is one of the main source of drinking water for Upper Silesia Region. In reference to Water Frame Directive matter since 2010 the strategic research project: „Integrated system supporting management and protection of dammed reservoir (ZiZoZap)”, which is being conducted on Goczałkowice reservoir, has been pursued. In the framework of this project complex groundwater monitoring is carried on. One aspect is vadose zone research, conducted to obtain information about changes in chemical composition of infiltrating water and mass transport within this zone. Based on historical data and the structural model of direct catchment of Goczałkowice reservoir location of the vadose zone research site was selected. At the end of November 2012 specially designed lysimeter was installed with 10 MacroRhizon samplers at each lithological variation in unsaturated zone. This lysimeter, together with nested observation wells, located in the direct proximity, create the vadose zone research site which main aim is specifying the amount of nitrate transport in the vertical profile.

Can the mass balance of the entire glacier area of the Tien Shan be estimated?

1992 ◽  
Vol 16 ◽  
pp. 173-179
Author(s):  
M.B. Dyurgerov ◽  
M.G. Kunakhovitch ◽  
V.N. Mikhalenko ◽  
A. M. Sokalskaya ◽  
V. A. Kuzmichenok
Keyword(s):  
Mass Balance ◽  
Vertical Profile ◽  
River Basins ◽  
Annual Runoff ◽  
Snow Accumulation ◽  
Tien Shan ◽  
Exponential Dependence ◽  
Glacier Area ◽  
Equilibrium Line Altitude ◽  
Boundary Area

The total area of glacierization of the Tien Shan in the boundary area of the USSR is about 8000 km2. The computation of mass balance was determined for this area in 12 river basins.In computation procedure, the vertical profile of snow accumulation in these regions and exponential dependence of variation of ablation with altitude are used. Thus the mass balance in each basin, bn, was calculated on the basis of these curves and represented in its relation with the equilibrium line altitude (ELA). It is shown that the relation ELA = f(bn) is linear when the range of bn values is close to zero, and in all altitude intervals this relation can be described by hypsographic curves, in all basins bn positive up to an ELA elevation of 3450 to 3500 m a.s.l. For average annual altitude of ELA, bn is negative for all regions. So the glaciers of these mountains add about 4 km3 of water to the total annual runoff.

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