Data product Baltic Thalweg (Level 4)

(Version 0.3, 22.09.2017, V. Mohrholz)

Description

The data set consists of CTD data of pressure, in-situ temperature, conservative temperature, absolute salinity and dissolved oxygen concentration along the Baltic thalweg transect. It starts in the Kiel Bight at 54°39.6’N, 10°45.6’E and follows the Baltic valley line to 58°58.4’N, 20°12.9’E in the northern Gotland Basin. The total length of the transect is 552 nautical miles (1022km). The data set is derived from validated in-situ measurements with a SeaBird CTD 911 system. The field data were gathered in frame of the IOW long term observation program in the central Baltic and the Baltic monitoring program (western Baltic), funded by the BSH. The field data were interpolated on an equidistant depth vector with 1m depth steps. The parameters conservative temperature and absolute salinity were calculated using the TEOS10 toolbox. The data set covers the ten year period from 2014 to 2019 with 5 grids per year, usually for February, March, May, July and November.

Available time range: November 2014 - August 2019

 

Structure of NetCDF file:

Global Attributes

Name	Content
title	Hydrographic data set of Baltic thalweg transect (CTD data at stations)
version	Version number of data product, date of data processing
subtitle	Cruise description string (e.g. used for figure captions)
datasetID	Internal cruise identifier (e.g. ‘btw2016_03’)
cruiseID	Offical cruise number, (e.g. ‘EMB124’)
reference	Data reference for citation of data product
publisher	Leibniz Institute for Baltic Sea Research (IOW)
rights	Level 3 data, only for internal use
creator	Name of operator
contact	Email address for information and support
description	Data set description text

 

Dimensions

Name	Axis	Long name	Unit	Description
depth	Z	Depth	m	Depth below surface, positive downward
time	T	Time	days	Time of CTD station
cruise	C	Cruise ID	none	Cruise identifier (e.g. '201603')

 

Variables

Name	Axis	Long name	Unit	Description
latitude	T-C	Latitude	deg N	Latitude of CTD profile
longitude	T-C	Longitude	deg E	Longitude of CTD profile
stat_dist	T-C	Station distance	km	Distance along the thalweg transect allocated to CTD station
bottom	T-C	Bottom depth	m	Bottom depth from echo sounder
Press	T-C	Pressure	dBar	Pressure value data
Temp	T-Z-C	in-situ Temperature	°C	in-sito Temperature data
CTemp	T-Z-C	Conservative temperature	°C	Conservative temperature data
ASal	T-Z-C	Absolute salinity	g/kg	Absolute salinity data
Oxy	T-Z-C	Dissolved Oxygen	μmol/kg	Dissolved Oxygen data
stat	T-C	Station	none	Station ID of particular cruise
stat_dmin	T-C	Data profile start depth	m	Data profile start depth of CTD station (positive down)
stat_dmax	T-C	Data profile end depth	m	Data profile end depth of CTD station (positive down)