Short Citation:
Northeast Fisheries Science Center, 2020: Environmental Monitors on Lobster Traps Database,

Item Identification

Title: Environmental Monitors on Lobster Traps Database
Short Name: Environmental Monitors on Lobster Traps (eMOLT)
Status: Completed

The eMOLT project is a non-profit collaboration of industry, science, and academics devoted to monitoring of the physical environment of the Gulf of Maine and the Southern New England shelf. In a series of phases funded by the Northeast Consortium (2001-2008), low-cost strategies have been developed to monitor the environment. While the primary variable is bottom temperature, salinity and current velocity have been measured as well with the help of nearly 100 lobstermen dispersed along the entire New England coast. We hope to extend our existing multi-year time series (as well as our monitoring capabilities), continue integration with the Northeast Regional Association for Coastal Ocean Observing Systems (NERACOOS), and contribute to whatever operational systems are developed for our region in the future.


We expect the primary users of eMOLT data, aside from the lobstermen themselves, will be local ocean circulation modelers. The need for data in initialization, assimilation, and validation of their numerical simulations is becoming more and more obvious. The complex time-varying nature of the Gulf of Maine system calls for incorporating as much data as possible in order to generate realistic flow fields. We hope to supplement the data supplied by NERACOOS by providing modelers with a extensive array of bottom observations as well as Lagrangian drifter tracks. Our hope is that these numerical models will someday help in our understanding of lobster larvae drift and the fate of any particles for that matter, such as Harmful Algal Blooms, along our coast. What are the mechanisms that govern the both the short-term and long-term variability of the GoM ecosystem and can we generate realistic, time-varying, 3-d simulations of these changes?


Theme Keywords

Thesaurus Keyword
None bottom temperature
None current velocity
None salinity

Temporal Keywords

Thesaurus Keyword
None continuous
None primarily fishing season May-Nov

Spatial Keywords

Thesaurus Keyword
None Gulf of Maine
None New England coast
None Southern New England Shelf

Stratum Keywords

Thesaurus Keyword
None benthic

Physical Location

Organization: Northeast Fisheries Science Center
City: Woods Hole
State/Province: MA
Country: USA

Data Set Information

Data Set Scope Code: Data Set
Data Set Type: Oracle Database
Maintenance Frequency: Weekly
Data Presentation Form: Table (digital)

Support Roles

Data Steward

CC ID: 212326
Date Effective From: 2001
Date Effective To:
Contact (Person): Manning, James
Address: 166 Water Street
Woods Hole, MA 02543
Email Address:
Phone: 508-495-4727


CC ID: 212965
Date Effective From: 2008
Date Effective To:
Contact (Organization): Northeast Fisheries Science Center (NEFSC)
Address: 166 Water Street
Woods Hole, MA 02543-1026
Phone: (508)495-2000
Business Hours: 8:00 a.m. to 4:30 p.m. Monday - Friday

Metadata Contact

CC ID: 204162
Date Effective From: 2015
Date Effective To:
Contact (Person): Manning, James
Address: 166 Water Street
Woods Hole, MA 02543
Email Address:
Phone: 508-495-4727


CC ID: 204163
Date Effective From: 2001
Date Effective To:
Contact (Person): Manning, James
Address: 166 Water Street
Woods Hole, MA 02543
Email Address:
Phone: 508-495-4727

Point of Contact

CC ID: 202471
Date Effective From: 2001
Date Effective To:
Contact (Person): Manning, James
Address: 166 Water Street
Woods Hole, MA 02543
Email Address:
Phone: 508-495-4727
Contact Instructions:

cell: 508-566-4080


Extent Group 1

Extent Group 1 / Geographic Area 1

CC ID: 202379
W° Bound: -75
E° Bound: -65
N° Bound: 45
S° Bound: 35

Approximately 70 fixed locations with nearly a decade of hourly time series

Extent Group 1 / Time Frame 1

CC ID: 202380
Time Frame Type: Continuing
Start: 2001

While some of the data in the archive is from previous projects, the actual eMOLT data starts in 2001.

Access Information

Security Class: Unclassified
Data Access Policy:

open to all

Data Access Procedure:

Served via ERDDAP:,

the data can be queried according to site code, time, location, and depth.

Alternatively, the data can be accessed directly into programming languages such as MATLAB or PYTHON and example scripts are provided.

Data Access Constraints:

some timeout limitations, no absolute restrictions apply although users are asked to voluntarily provide a brief description of how they intend to use the data prior to download.

Data Use Constraints:

No restrictions apply.

Metadata Access Constraints:


Metadata Use Constraints:


Distribution Information

Distribution 1

CC ID: 212673
Download URL:

Distribution 2

CC ID: 767869
Download URL:

NCEI Accession 0162412



CC ID: 202381
URL Type:
Online Resource
File Resource Format: HTML

description of the project with many links to results and data

Technical Environment


Oracle 10g nova database

Data Quality


temperature ~0.2 degC

position ~1km

depth ~5% of water column

VEMCO Minilog II-T Temperature Data Logger:

ONSET HOBO TidbiT v2 Water Temperature Data Logger:


temperature <0.1 degC based on near-annual calibration checks


care obviously taken to account for large seasonal cycle

Completeness Measure:

another decade is needed to consider "climatic" time scales but, given the hourly time series, many short term processes can be examined (tide, wind, seasonal, interannual, etc).


temperature ~0.1

depth ~5% of water column depth

Completeness Report:

Quality Control Procedures Employed:

Instrument is mailed to the scientist and the data is downloaded to disk within a few days. Data is run through a series of Python programs to conduct range and delta checks and visual graphics. Spikes of more than X standard deviations are removed where X depends on the geographic location and season. Hardcopy plots are mailed to each participant after the annual download and archiving.

Data Management

Have Resources for Management of these Data Been Identified?: Yes
Approximate Percentage of Budget for these Data Devoted to Data Management: Unknown
Do these Data Comply with the Data Access Directive?: Yes
Is Access to the Data Limited Based on an Approved Waiver?: No
Approximate Delay Between Data Collection and Dissemination: There is approximately a week between when the fishermen hauls his gear w/the sensor and when the data arrives at my desk, gets processed, and loaded each year.
Actual or Planned Long-Term Data Archive Location: Other
If World Data Center or Other, Specify: ERDDAP with the data actually housed on NEFSC disks
Approximate Delay Between Data Collection and Archiving: One week, same as above, although we are currently working on a system to make eMOLT data collection in realtime where it would be telemetered and archived within minutes of the fisherman hauling his gear.
How Will the Data Be Protected from Accidental or Malicious Modification or Deletion Prior to Receipt by the Archive?:

Archival of source data preserving unaltered collected data, Scheduled backups, Remote storage backups, Password protection


Lineage Statement:

Child Items

Rubric scores updated every 15m

Rubric Score Type Title
Entity (ENT) eMOLT

Catalog Details

Catalog Item ID: 25149
Metadata Record Created By: Patricia L Jones
Metadata Record Created: 2015-05-27 16:57+0000
Metadata Record Last Modified By: SysAdmin InPortAdmin
Metadata Record Last Modified: 2020-05-14 05:28+0000
Metadata Record Published: 2016-07-18
Owner Org: NEFSC
Metadata Publication Status: Published Externally
Do Not Publish?: N
Metadata Next Review Date: 2017-07-19