1,721,061 research outputs found
Physical oceanography during POLARSTERN cruise ANT-XXI/3 (EIFEX)
No full textThe track of Polarstern Cruise ANTXXI/3-"EIFEX"- leaving from Cape Town on 21st January 2004 and arriving back in Cape Town on 25th March 2004. The purpose of this cruise was to conduct an iron fertilisation experiment in the ACC. The reason for using an eddy was that the water fertilised with iron sulphate would be trapped and relatively easy to follow. The first eddy (Eddy 1) selected on the basis of altimeter data was at about 50°S, 18°E. This eddy was surveyed during a period of 7 days between 25th January and 1st February 2004 by CTD/Rosette casts along five equally spaced meridional sections. Along the westernmost section, 17°E, the station spacing was 5 mi (9 km), and along the other 4 (17°40', 18°20', 19°00' and 19°40' E), it was 12 mi (22 km); the sections were completed systematically working from west to east. Investigation revealed that the initial chlorophyll concentration was too low for the fertilisation experiment and so this eddy was rejected, but not before a useful set of physical data had been obtained. Instead, a second eddy (Eddy 2), at about 49°S, 2°E was selected for the experiment and was ultimately occupied for a period of 40 days. Altogether, this eddy was investigated during the period 8th February to 20th March 2004; however, the data for the initial CTD/Rosette survey were collected during a period of 6 days between 14th and 20th February. The stations were evenly spaced 12 mi (22 km) apart meridionally and zonally, or 12' latitude and about 18.6' of longitude, with ten stations along each of eight equally spaced meridional sections between 1°19' and 3°29' E. The sections were collected systematically from west to east
Links to master tracks in different resolutions of POLARSTERN cruise PS113 (ANT-XXXIII/4), Punta Arenas - Bremerhaven, 2018-05-08 - 2018-06-11
No full textLinks to master tracks in different resolutions of POLARSTERN cruise PS113 (ANT-XXXIII/4), Punta Arenas - Bremerhaven, 2018-05-08 - 2018-06-1
Station list and links to master tracks in different resolutions of POLARSTERN cruise ANT-XXIII/2, Cape Town - Punta Arenas, 2005-11-18 - 2006-01-13
No full textStation list and links to master tracks in different resolutions of POLARSTERN cruise ANT-XXIII/2, Cape Town - Punta Arenas, 2005-11-18 - 2006-01-1
Geostrophic Stream function of the Weddell Gyre derived from Argo floats from 2002 to 2016, integrated for the upper 50-2000 dbar
No full textAll available Argo float data from 2002 to 2016 in the Weddell Sea region were used to fit a stream function of the horizontal circulation of the Weddell Gyre. Argo float trajectories where sequences of positions are available (i.e., under ice profiles have an interpolated position and are therefore excluded) were used to estimate absolute velocity at the parking depth, which is then objectively mapped and fitted with a stream function using a cost function. Within the cost function, boundary conditions are defined such that the flow at the boundary is parallel to the boundary itself. The cost function provides the best fit stream function representative of the entire gyre circulation. The resulting stream function represents horizontal circulation at the parking depth of the Argo floats (usually 800 m; those with a different parking depth were corrected accordingly). Objectively mapped density data from the Argo float profiles were then incorporated to provide geostrophic stream functions for 41 levels between 50 and 2000 dbar. These were then vertically integrated to ultimately provide a geostrophic stream function of the upper 50-2000 dbar of the Weddell Gyre, representative of its mean horizontal circulation. Units are in Sverdrups (Sv), where 1 Sv = 1x10^6 m^3/s, and is the standard unit for quantifying volume transports. Full details of the method for the original stream function data, and the subsequent improvements for the published dataset are available in the supplemental links
Raw data of SCADCP (self-contained Acoustic Doppler Current Profiler) from mooring AWI229-7
No full textThe ADCP used was of the type RDI Workhorse Longranger (Teledyne RD Instruments USA, Poway, California), using a four-beam, convex configuration with a beam angle of 20° and a frequency of 76.8 kHz. The instrument was moored at mean depth of 389 m in upward-looking mode and measured horizontal and vertical currents and acoustic backscatter intensity. Heading, pitch and roll, pressure and temperature data were also collected. The number of depth cells was set to 80 with a bin size of 8 m. The sampling interval was set to 1 ping per ensemble with a ping rate of about 1 ping every 4 minutes. The mooring AWI229-7 was deployed in December 2005 during R. V. Polarstern cruise ANT-XXIII/2 and recovered during R. V. Polarstern cruise ANT-XXIV/3 in March 2008.
Project: Lazarev Sea Krill Study (LAKRIS), Funded by German Ministry of Education and Researc
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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