Long-term observations on the Bering Sea shelf: biophysical moorings at sites 2 and 4 as sentinels for ecosystem change (NPRB Projects 410, 517)

Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator: Phyllis Stabeno, NOAA/PMEL.EcoFOCI
Originator: Jeffery Napp, NOAA/AFSC, EcoFOCI
Originator: Terry Whitledge, UAF, Inst. of Marine Science
Publication_Date: Unpublished material
Title:
Long-term observations on the Bering Sea shelf: biophysical moorings at sites 2 and 4 as sentinels for ecosystem change (NPRB Projects 410, 517)
Geospatial_Data_Presentation_Form: tabular digital data
Description:
Abstract:
Biophysical measurements have been made at mooring Site 2 (56.88°N, 164.03°) almost
continuously since 1995, providing the longest near continuous time-series of
biophysical variables on the Bering Sea shelf. A series of moorings have also been
deployed at Site 4 (57.85°N, 168.87°W) since 1995, providing almost six years of
more sporadic data. Added to the biophysical data collected by the moorings, water
property measurements have been made at locations around the moorings and along the
70-m transect since 1995. Such long-term observations provide critical data that
allow characterizations of interannual variability, quantification of regime shifts
and climate change. This project partially funds continued measurements at both Sites
2 and 4, together with water samples and plankton samples around both mooring sites and
along the monitoring line
.
Purpose:
CTD observations provide critical profile data defining hydrology in areas where moorings have been deployed, supporting these longer-term time series data sets. Transects allow a view of spatial patterns in the water column, allowing characterizations of seasonal and interannual variability, and privide critical calibration for mooring data.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20050512
Ending_Date: 20050528
Currentness_Reference:
ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Description_of_Geographic_Extent:
Moorings M2 and M4 are located on the southeast Bering Sea shelf near the 70-meter isobath. CTD data are collected over various areas of the southeast Bering Sea shelf during mooring cruises. Casts are taken near the moorings and at other areas of interest, including the Pribilof Islands, near the Aleutian Islands, and along the 70-meter isobath.
Bounding_Coordinates:
West_Bounding_Coordinate: -179.00000
East_Bounding_Coordinate: -157.00000
North_Bounding_Coordinate: 63.00000
South_Bounding_Coordinate: 52.00000
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: CTD
Theme_Keyword: Oceanography
Theme_Keyword: Physics
Theme_Keyword: Biophysical
Theme_Keyword: temperature profile
Theme_Keyword: salinity profile
Theme_Keyword: nitrate
Theme_Keyword: chlorophyll
Theme_Keyword: oxygen
Theme_Keyword: Fluorescence
Theme_Keyword: temperature
Theme_Keyword: conductivity
Theme_Keyword: salinity
Theme_Keyword: pressure
Theme_Keyword: mixed layer
Theme_Keyword: 70-meter isobath
Place:
Place_Keyword_Thesaurus: None
Place_Keyword: Bering Sea
Place_Keyword: southeast Bering Sea shelf
Place_Keyword: Pribilof Islands
Place_Keyword: Aleutian Islands
Place_Keyword: Alaska
Place_Keyword: Bristol Bay
Place_Keyword: M2 mooring
Place_Keyword: M4 mooring
Place_Keyword: 70-meter isobath
Stratum:
Stratum_Keyword_Thesaurus: None
Stratum_Keyword: 1-meter averaged surface to near-bottom
Stratum_Keyword: lower trophic
Temporal:
Temporal_Keyword_Thesaurus: None
Temporal_Keyword: 2005
Temporal_Keyword: Spring
Access_Constraints: None
Use_Constraints:
Users of data are asked to give credit to the Principal Investigators, and data-gathering and funding agencies.
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Phyllis Stabeno
Contact_Organization: NOAA/PMEL/EcoFOCI
Contact_Address:
Address_Type: mailing and physical
Address: 7600 Sand Point Way NE
Address: Building 3
City: Seattle
State_or_Province: Washington
Postal_Code: 98115
Country: USA
Contact_Voice_Telephone: 206-526-6453
Data_Set_Credit:
EcoFOCI project (NOAA/PMEL)
University of Washington JISAO
North Pacific Research Board (Projects 410, 517)
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Data_Quality_Information:
Logical_Consistency_Report:
not applicable
Completeness_Report:
Data are processed using Seabird CTD software and calibration file. Post-processing includes filtering extreme outliers, extrapolation of values from the top value collected at 3-4m to the surface. Each cast is visually reviewed for reasonableness and density inversions (greater than 0.02 sigma-t) caused by spurious measurements. This process is facilitated by comparison of the outputs of the 2 temperature and conductivity sensors. Profile data are bin-averaged to 1 meter. Salinity is derived using Seabird processing software that uses IPTS-68 and PSS-78. see SBE Data Processing manual appendix V:
http://www.seabird.com/pdf_documents/manuals/SBEDataProcessing_7.17a.pdf
Lineage:
Methodology:
Methodology_Type: Field
Methodology_Description:
Our CTD is a Seabird 911plus with dual sensors (temperature and conductivity). At each CTD location, the CTD rosette was lowered to 10 meters to equilibrate, brought to surface, then deployed to a close-to-bottom depth, at ~30m/minute down to 150 m (average speed) and ~50m/minute below that. Water bottles were fired at desired depths on the upcast. Ascent was at the same or faster rate. Once on board, numerous water samples were taken from Niskin bottles.
Process_Step:
Process_Description:
Data are processed using Seabird CTD software and calibration file. Bottle salt calibration samples were taken approximately every other cast. Post-processing at the Pacific Marine Environmental Laboratory includes filtering extreme outliers, extrapolation of values from the top value collected at 3-4m to the surface. Each cast is visually reviewed for reasonableness and density inversions (greater than 0.02 sigma-t) caused by spurious measurements. This process is facilitated by comparison of the outputs of the 2 temperature and conductivity sensors. Profile data are bin-averaged to 1 meter. Salinity is derived using Seabird processing software that uses IPTS-68 and PSS-78. see SBE Data Processing manual appendix V: http://www.seabird.com/pdf_documents/manuals/SBEDataProcessing_7.17a.pdf
Source_Used_Citation_Abbreviation:
http://www.seabird.com/pdf_documents/manuals/SBEDataProcessing_7.17a.pdf
Source_Used_Citation_Abbreviation:
http://www.ecofoci.noaa.gov/efoci_dataDescription.shtml
Process_Date: Unknown
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Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Geographic:
Latitude_Resolution: 0
Longitude_Resolution: 0
Geographic_Coordinate_Units: Decimal degrees
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Entity_and_Attribute_Information:
Overview_Description:
Entity_and_Attribute_Overview:
CTD data set from R/V Thompson, mooring cruise tn179 Leg 3, consisting of 118 casts collected May 12- 28, 2005.
Each CTD cast creates a vertical profile of data. Primary data types are temperature and conductivity (dual sensors), and pressure. Salinity is derived from these. Additional instruments are added to the deployed package as defined by the study and cruise circumstances. Other variables include chlorophyll fluorescence, nutrients, and Photosynsynthetically Active Radiation (PAR), Chlorophyll and nutrients are collected at selected depths. Other data are averaged to 1-meter depth values.
Entity_and_Attribute_Detail_Citation:
http://www.ecofoci.noaa.gov/efoci_dataDescription.shtml
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Metadata_Reference_Information:
Metadata_Date: 20080501
Metadata_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Peggy Sullivan
Contact_Organization: NOAA/PMEL/EcoFOCI and UW/JISAO
Contact_Address:
Address_Type: mailing and physical
Address: 7600 Sand Point Way NE
Address: Building 3
City: Seattle
State_or_Province: Washington
Postal_Code: 98115
Country: USA
Contact_Voice_Telephone: 206-526-6185
Contact_Electronic_Mail_Address: peggy.sullivan@noaa.gov
Contact_Electronic_Mail_Address: dave.kachel@noaa.gov
Metadata_Standard_Name: FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
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