Vertical Water Transport Research Articles

Entrainment and vertical transport of deep-ocean water by buoyant hydrothermal plumes

Submarine hydrothermal vents produce effluent plumes in the water column which can be easily detected with tracers such as 3He, manganese and methane1–3. Comparison of the tracer concentrations and temperature anomalies in such plumes with direct measurements of the pure vent waters shows that the plumes are typically mixtures of 1 part vent water with 104 parts ambient sea water1. However, the extent to which hydrothermal plumes entrain and transport sea water and contribute to deep-ocean mixing is not known. We present here hydrographie data collected in the vicinity of an active hydrothermal field on the Endeavour segment of the Juan de Fuca Ridge where a well-defined effluent layer resides in the water column ∼200 m above the depth of the vent field. The temperature and salinity signature of this layer indicates that a small volume of hot vent water can be very efficient at entraining ambient sea water. Directly above the Endeavour vent field, the effluent layer is composed of 0.01% vent water, 30% ambient water normally found at that depth, and ∼70% entrained water which has been transported from deeper in the water column.

Possible effects of stratospheric aerosol layers on the vertical transport of water

A possible influence of stratospheric aerosols, composed of mixtures of water and sulfuric acid, on the vertical flux of water and on the relative humidity existing at the base of the stratosphere is considered. The existence of long-lived aerosol layers in the intertropical region is related to the vertical velocity profile in the ascending branch of the Hadley cell. Fluctuations of the temperature profile cause the water fraction to evaporate at the bottom of the layer and to condense in the upper part, and influence the diffusion coefficients. Thus it is envisaged that aerosols within a range of radii grow and evaporate, respectively, at the upper and lower levels of the layer: in view of the resulting change in water mass a variable balance between the opposite effects of sedimentation and of the Hadleycell updraft is determined which causes the particles to oscillate along the vertical. At the bottom, water vapour is separated from the particles by molecular diffusion, which has little influence on the aerosol motion. Calculations indicate that the mechanism does work but that its effect is small, a reduction in humidity of a few percent typically, and could be as high as 10 percent for unusually large amounts of H2SO4, such as those obtained after strong volcanic eruptions.

Comment [on “Atmospheric HT and HTO, 3, Vertical transport of water in the stratosphere” by A. S. Mason and H. G. Östlund

Comment [on “Atmospheric HT and HTO, 3, Vertical transport of water in the stratosphere” by A. S. Mason and H. G. Östlund

Reply [to “Comment on ‘Atmospheric HT and HTO, 3, vertical transport of water in the stratosphere’ by A. S. Mason and H. G. Östlund”

Reply [to “Comment on ‘Atmospheric HT and HTO, 3, vertical transport of water in the stratosphere’ by A. S. Mason and H. G. Östlund”

Correction [to “‘Atmospheric HT and HTO: 3. Vertical transport of water in the stratosphere’”

Correction [to “‘Atmospheric HT and HTO: 3. Vertical transport of water in the stratosphere’”

Atmospheric HT and HTO: 3. Vertical transport of water in the stratosphere

A series of sampling flights was made to determine the vertical distribution of HT and HTO in the upper troposphere and lower stratosphere up to 18-km altitude. The HT appears to be well mixed, but striking vertical gradients of HTO were found in the region from 10 to 18 km. These gradients, essentially constant to 18 km, were used to estimate a characteristic time of 2 years for turnover of water vapor in the lower stratosphere.

Some influences of zero-tillage on the structure and stability of a fine-textured river levee soil.

By means of physical and micromorphological analyses the difference in soil structure caused by ploughing and 5 years zero-tillage on a fine-textured fluviatile deposit was characterized. Although bigger pores were less stable and more affected by compaction, within each pore size class stability varied widely. Zero-tillage resulted in a denser and more homogeneous soil in which small aggregates disappeared and aggregate stability increased whereas pore continuity was not improved very much. Active pseudogleying was responsible for extensive bleaching in the zero-tillage profile, caused by a periodical lack of oxygen. The earthworm population increased markedly, but most earthworms were small. The number of large worm holes decreased sharply with depth, indicating a poor environment for the deep-burrowing worms which improve vertical water transport. Temporary pool formation occurred on part of the zero-tillage plots in the autumn and winter of the last few years, and after a heavy rainstorm in June 1975, when many worms died on the zero-tillage plots. (Abstract retrieved from CAB Abstracts by CABI’s permission)

A Numerical Study on the Initiation of Warm Rain

Abstract A time-dependent Eulerian model of the warm-rain process has been developed to investigate the roles of stochastic coalescence and vertical water transport in the development of convective precipitation. Several model runs were made using experimental values of cloud droplet spectra, liquid water contents, and updraft profiles to simulate typical maritime warm cumuli. Comparative model runs made with and without an updraft illustrate the importance of transitory water accumulations in explaining the coalescence growth of cloud droplets to precipitation sizes within a reasonable time and the sudden onset of large-droplet rain in convective showers. The maritime runs were then repeated, this time seeding just above the level of updraft maximum with spray rates and seeding droplet spectra used in the water-spray field experiments of the University of Chicago Cloud Physics Project. Within the framework of the model, the seeded cases show significantly earlier precipitation onset than their non-seeded...

Time of vertical water transport in ocean : Chekotillo K. A., 1965. (In Russian; English abstract). Okeanolog. Issled., Rez. Issled. po Programme Mezhd. Geofiz. Goda, Mezhd. Geofiz. Komitet, Prezidiume Akad. Nauk, SSSR, No. 13: 37–40

Time of vertical water transport in ocean : Chekotillo K. A., 1965. (In Russian; English abstract). Okeanolog. Issled., Rez. Issled. po Programme Mezhd. Geofiz. Goda, Mezhd. Geofiz. Komitet, Prezidiume Akad. Nauk, SSSR, No. 13: 37–40

Patterns of Water Movement in Forest Trees

1. Experiments were conducted in central and north-central Wisconsin on paths of upward water movement in stems of trees unilaterally injected at the base with acid fuchsin dye. The path of uptake was traced by felling the injected trees and observing the pattern of dye staining in horizontal 1-inch-thick cross-sections of the stem taken at intervals of 2 feet along the stem. Four species of gymnosperms and seven of angiosperms were studied. 2. Marked variations in paths of water movement were observed among genera and species. There also was considerable variation in patterns of dye ascent among individual trees of certain species, but in other species the pattern among trees was very consistent. 3. Deviation in water movement from a vertical path was more common over a wide range of species than was strictly vertical water transport. Some tendency for spiraling of water in its ascent was observed in all species studied. 4. Patterns of water movement were correlated with spiraling of xylem elements. Henc...

Inorganic nutrients in the sea

Examines the vertical transport of oceanic water and nutrients, the surface distribution of inorganic phosphates and oxygen, and the vertical distribution of nutrients.

Physiology of Pines Infested with Bark Beetles

1. Dendroctonus frontalis and I ps avulsus bore through the bark and tunnel in the phloem. The beetle inoculates the wood with fungi and the entrance holes and beetle galleries serve to expose the wood to the air. 2. The outer rings of the tree lose the capacity to conduct dye solutions successively from the first ring toward the center. This gradually advances to the center of the tree and cuts off the supply of water to the leaves which empty the top of water and die. 3. Failure of the outer rings to conduct dye solutions is intimately associated with drying of the wood. The suggestion is made that theaccumulation of air in the rings, which accompanies the loss of moisture, forms a resistance sufficient to stop the vertical and lateral transport of water. 4. The failure of the wood to conduct dye solutions is also closely associated with the penetration of the wood by fungi. Ceratostomellapini and fungus no. I are practically the only fungi which penetrate deeply into the wood during the early stages of attack. Inoculations show that C. pini growing alone is able to kill the trees, but fungus no. I has not been tested. 5. From the close connection between the drying and the position of the fungi in the wood, it is suggested that the drying is acceleratedby the action of the fungi on the cells. 6. The stoppage of conduction is probably also associated with the aspiration of the tori, as indicated by NELSON'S work. He suggests that blocking of the pits of the tracheids by the tori might account for the stoppage of conduction.