The influence of thermal expansion the Earth's atmosphere on stability vertical stratification fluid density and temperature is studied. We show that such an leads to instability incompressible flows. Modified by coefficient, a new expression for Brunt-Väisälä frequency derived, critical value coefficient which occurs revealed.

Over the 20th century, surface water temperatures have increased in many lake ecosystems around the world, but long-term trends in the vertical thermal structure of lakes remain unclear, despite the strong control that thermal stratification exerts on the biological response of lakes to climate change. Here we used both neo- and paleoecological approaches to develop a fossil-based inference mod...

galbanum (ferula gummosa bioss) is a medicinal, commercial and industrial plant in iran but its cultivation is restricted by seed dormancy. therefore, a study was conducted to determine class and environmental requirements for breaking of seed dormancy. during imbibition study, both scarified and intact seeds exhibited similar pattern in water uptake and it seems there is not physical dormancy....

The Ekman-Taylor problem for the planetary boundary layer is solved in the case of a thermal wind which varies linearly with height. The upper boundary condition is a vanishing ageostrophic wind, while the lower boundary condition is continuity of the stress vector across the interface between the planetary boundary layer and the surface layer. The latter condition is used to determine the magn...

The paper presents a mathematical analysis of the stability of generalized hydromagnetic thermal shear flows in the Presence of horizontal magnetic field. The physical configuration is that of a horizontal layer of an incompressible inviscid heat conducting fluid of zero electrical resistivity in which there is a differential streaming in the horizontal direction and density variation in the ve...

We present an asymptotic form of the Boussinesq equations in the limit of small Péclet numbers i.e. when the time scale of motions is much larger than the time scale of thermal diffusion. We find that, in this limit, the effects of thermal diffusion and stable stratification combine in a single physical process. This process is an anisotropic dissipation (not effective for horizontal motions) w...

Studies of hybrid nanofluids flowing over various physical geometries and conditions are popular among researchers to understand the behavior these fluids. Thenceforth, numerical solutions for Ag-CuO/H2O nanofluid flow a stretching sheet with suction, magnetic field, double stratification, multiple slips effects analyzed in present study. Governing equations boundary introduced describe problem...

Microorganisms play pivotal roles within aquatic ecosystems, affecting their structure, functioning and services. However, little is known about the effects of water stratification and mixing on the aquatic microbial community dynamics in subtropical reservoirs. In this study, we explored vertical and seasonal patterns of microbial diversity in the Dongzhen Reservoir (southeast China). Quantita...

We discuss the possibility that astrophysical accretion disks are dynamically unstable to nonaxisymmetric disturbances with characteristic scales much smaller than the vertical scale height. The instability is studied using three methods: one based on the energy integral, which allows the determination of a sufficient condition of stability, one using a WKB approach, which allows the determinat...

Seasonal variations of the seawater properties (e.g. temperature, salinity, density and chlorophyll-a) in western part of the southern coastal waters of the Caspian Sea near the Iranian coast were studied. A portable CTD probe was applied for profiling from sea surface to bottom at 23 stations. Maximum depth of the profiling stations was more than 470 m in the study area. Vertical structure of ...