Daily inundation induced seasonal variation in the vertical distribution of soil water salinity in an estuarine mangrove forest under a tropical monsoon climate

Ozone soundings made from Dakshin Gangotri, Antarctica during 1987 are presented. The vertical distribution of ozone over Antarctica is characterised by a double peak profile, one around 200-150 hPa and the other around 50 hPa. During late winter-early spring the upper peak is considerably depleted. Tropospheric ozoe remains low and nearly constant throughout the year.

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Vertical distribution, seasonality and troposphericity of ice-supersaturated air masses in the northern mid-latitudes from regular in-situ observations by passenger aircraft

10.5194/egusphere-egu2020-8992 ◽

2020 ◽

Author(s):

Andreas Petzold ◽

Susanne Rohs ◽

Mihal Rütimann ◽

Patrick Neis ◽

Berkes Florian ◽

...

Keyword(s):

Seasonal Variation ◽

Vertical Distribution ◽

North Atlantic ◽

Observation Data ◽

European Research ◽

Air Masses ◽

The North ◽

The North Atlantic ◽

Passenger Aircraft ◽

The Vertical Distribution

The vertical distribution and seasonal variation of water vapour volume mixing ratio (H2O VMR), relative humidity with respect to ice (RHice) and particularly of regions with ice-supersaturated air masses (ISSR) in the extratropical upper troposphere and lowermost stratosphere are investigated at northern mid-latitudes over the regions Eastern North America, the North Atlantic and Europe for the period 1995 to 2010.Observation data originate from regular and continuous long-term measurements of H2O VMR, temperature and RHice by instrumented passenger aircraft in the framework of the European research program MOZAIC which is continued as European research infrastructure IAGOS (from 2011; see www.iagos.org). The observation data are analysed with respect to the thermal and dynamical tropopauses, as provided by ERA-Interim. Additionally, collocated O3 observations from MOZAIC are used as tracer for stratospheric air masses.Our key results provide in-depth insight into seasonal and regional variability and tropospheric nature of ice-supersaturated air masses at various distances from the tropopause layer. For the vertical distribution and seasonal variation of ISSR occurrence we show a comparison of our results to radio soundings and to satellite observations of cirrus cloud occurrence from AIRS and TOVs Path B instruments. Finally, for all three regions, we investigate the trends and the dependencies of ISSR occurrence on the North Atlantic Oscillation (NAO) index.

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Seasonal variation of the crustacean fauna in the belowground and aboveground strata in a Halodule wrightii meadow of northeastern Brazil

Iheringia Série Zoologia ◽

10.1590/1678-4766e2017048 ◽

2017 ◽

Vol 107 (0) ◽

Author(s):

Kcrishna V. S. Barros ◽

Jesser F. Souza-Filho ◽

Ricardo J. C. Paiva ◽

Catarina L. Araújo-Silva ◽

Alexandre O. Almeida ◽

...

Keyword(s):

Spatial Distribution ◽

Seasonal Variation ◽

Vertical Distribution ◽

The Other ◽

Northeastern Brazil ◽

Halodule Wrightii ◽

The Vertical Distribution

ABSTRACT The different microhabitats provided by seagrasses and the habit of the species determinate the vertical distribution of crustaceans. This study verified the influence of the seasonality on the spatial distribution of the crustacean community associated with a Halodule wrightii meadow. From April 2006 to July 2007, we performed fifteen samplings in Goiabeiras Beach, Ceará State, each with five sectioned replicates in belowground and aboveground. Cumaceans and the amphipod Hyale media (Dana, 1853) had a higher frequency, density, and dominance than the other taxa, in both strata. The community exhibited gradual changes along the study, in both the belowground and aboveground strata, but the seagrass structure was not sufficient to explain the vertical distribution of the crustacean fauna along the time.

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Travelling disturbances in the ionosphere

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1950.0095 ◽

1950 ◽

Vol 202 (1069) ◽

pp. 208-223 ◽

Cited By ~ 94

Keyword(s):

Seasonal Variation ◽

Vertical Distribution ◽

Sudden Change ◽

Frequent Occurrence ◽

Vertical Movements ◽

Short Period ◽

The Mean ◽

The Vertical Distribution

Methods have been developed for the examination of the horizontal and vertical movements of short-period disturbances in the ionosphere. It has been found that quasi-periodic travelling disturbances with periods of from 10 to 60 min. are of frequent occurrence in the F region by day. They appear as temporary variations in the vertical distribution of ionization which show a horizontal progression and a vertical progression downwards. The horizontal directions of travel have a well-defined mean direction on most days. The mean direction shows a marked seasonal variation with a sudden change at each equinox. The horizontal rate of travel is usually between 5 and 10 km./min., and the rate of vertical progression downwards is approximately half the horizontal rate. The disturbances are considered to be variations of a compressional type in the atmosphere resulting in changes in the distribution of ionization.

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