(UL)
-
Measurements of near-bottom stress and turbidity in the Gulf of Trieste during the passage of vessels [Elektronski vir] : EGU-2016Malačič, VladoThe Gulf of Trieste (GT) is a semi-enclosed 20 x 20 km gulf in the northernmost part of the Adriatic Sea with depths that reach 24 m at the most. Sediments in the southern (Slovenian) side of GT ... inside the shallow Bay of Koper, where measurements of near-bottom stress took place, are composed primarily of clayey silt (2-63 um). The observation of currents and turbidity took place inside the Bay of Koper at a location inside the shipping route, where the bottom depth is around 19 m. The goal of measurements was to study the bottom erosion due to changes to flow fields by ship movements (and due to propeller wakes). High-frequency measurements of currents and turbulence near the sea bottom were conducted with two Vector instruments (Nortek AS) with pressure sensors in the interval 123-31 July 2013, mounted at heights 0.2 m and 1.3 m above the sea bottom. Turbidity was measured with the same frequency with Seapoint IR (880 nm) turbidimeters placed at the same heights. In addition, turbidity was measured also with the "old" Minitracka II instrument of Chelsea Instruments that functioned at 470 nm. 10 s averages of 1 s measurements were recorded. When the voltage output of this instrument surpassed the chosen threshold value (e.g. 2 V out of 5 V range) the triggering signal was sent to start measurements of the size distribution of suspended sediments and their falling speeds with the laser in-situ scattering and transmissometery (LISST-STX). In the interval 7-19 November 2013 currents over the whole water column with vertical resolution of 0.5 m have been also surveyed with the 1 MHz ADCP instrument (Nortek AS) with a sampling frequency of 1/s, where 10 s averages were recorded. It appears that pure shipʹs dislocation of a mass of fluid, which may easily surpass 10^5 tons, is important in the erosion of the bottom. We have confirmed this by velocity and stress peaks near the sea-floor in the Bay of Koper that were frequently accompanied by peaks of turbidity during vessels% passages. Ten-second-average ADCP current-meter measurements showed a synchronous and sharp jump of velocities over a large part of the water column during vessels passage, the vertical extension of disturbance depends on the vessels% characteristics and its speed. At the time of velocity peak a sharp pressure drop (of app. 0.1-0.2 dbar) was recorded at the bottom of the bay due to the "squat" effect. Twenty events ship passages were studied between 23 and 31 July 2013. The velocity magnitude peak above the "ambient currents" for about 0.5 m/s within only 60 s is symmetric with respect to the peaks position. This deviates from the supposed time asymmetry in the propellerʹs jet. The effect of the latter seems to be less important at the place of measurements.Source: Geophysical research abstracts [Elektronski vir]. - ISSN 1607-7962 (Vol. 19, št. EGU2017-preview, 2017, str. 1)Type of material - conference contribution ; adult, seriousPublish date - 2017Language - englishCOBISS.SI-ID - 4307279
Link(s):
https://administrator.copernicus.org/authentication.php?cosession=5909bfa510be39-53042215-mza ogled predobjave se je potrebno logirati
Author
Malačič, Vlado
Topics
oceanografski podatki |
numerično modeliranje |
tokovanje |
veterno polje |
Jadransko morje |
hydrology |
hydrology |
oceanographic data |
numerical modelling |
wind forcing |
turbulence
![loading ... loading ...](themes/default/img/ajax-loading.gif)
Shelf entry
Permalink
- URL:
Impact factor
Access to the JCR database is permitted only to users from Slovenia. Your current IP address is not on the list of IP addresses with access permission, and authentication with the relevant AAI accout is required.
Year | Impact factor | Edition | Category | Classification | ||||
---|---|---|---|---|---|---|---|---|
JCR | SNIP | JCR | SNIP | JCR | SNIP | JCR | SNIP |
Select the library membership card:
If the library membership card is not in the list,
add a new one.
DRS, in which the journal is indexed
Database name | Field | Year |
---|
Links to authors' personal bibliographies | Links to information on researchers in the SICRIS system |
---|---|
Malačič, Vlado | 05226 |
Source: Personal bibliographies
and: SICRIS
Select pickup location:
Material pickup by post
Delivery address:
Address is missing from the member's data.
The address retrieval service is currently unavailable, please try again.
By clicking the "OK" button, you will confirm the pickup location selected above and complete the reservation process.
By clicking the "OK" button, you will confirm the above pickup location and delivery address, and complete the reservation process.
By clicking the "OK" button, you will confirm the address selected above and complete the reservation process.
Notification
Automatic login and reservation service currently not available. You can reserve the material on the Biblos portal or try again here later.
Subject headings in COBISS General List of Subject Headings
Select pickup location
The material from the parent unit is free. If the material is delivered to the pickup location from another unit, the library may charge you for this service.
Pickup location | Material status | Reservation |
---|
Reservation in progress
Please wait a moment.
Reservation was successful.
Reservation failed.
Reservation...
Membership card:
Pickup location: