Sea-air methane fluxes measured using an eddy-covariance technique on RRS James Clark Ross from January 2019 to March 2021

This dataset contains sea-air methane flux data from January 2019 to March 2021 measured using a Picarro G2311-f greenhouse gas analyser onboard RRS James Clark Ross, in the Southern Ocean, Arctic Ocean and Atlantic Ocean. The fluxes are 2 hour averaged and have been filtered based on wind direction to data corresponding to wind coming from behind the ship to remove sources of pollution from the ship stack. Limit of detection for the flux data are calculated for each cruise by multiplying the standard deviation of the random noise by three.





This work was supported by the Natural Environment Research Council and the ARIES Doctoral Training Partnership (grant no. NE/S007334/1). Royal Holloway, University of London was funded by NERC through grants NE/V000780/1 and NE/N016211/1. Anna E. Jones and Katrin Linse were part of the British Antarctic Survey Polar Science for Planet Earth Programme funded by the Natural Environment Research Council (NERC) [NC-Science]. The measurements from the Royal Research Ship James Clark Ross (JCR) were principally supported by the UK Natural Environment Research Council's ORCHESTRA project (Grant No. NE/N018095/1). The Picarro analyser was funded by the European Space Agency funding (ESA AMT4OceanSatFlux project, Grant No. 4000125730/18/NL/FF/gp). This work further contributes to the NERC MOYA project (Grant No. NE/N015932/1).

Simple

Date (Creation)
2024-01-10
Date (Revision)
2024-01-10
Date (Publication)
2024-01-10
Date (released)
2024-01-10
Edition

1.0
Unique resource identifier
https://doi.org/10.5285/c9ed4746-f104-4117-ba60-174c5275e2fe
Codespace

doi
Unique resource identifier
GB/NERC/BAS/PDC/01814
Codespace

https://data.bas.ac.uk/

Unique resource identifier
NE/S007334/1
Codespace

award
Unique resource identifier
NE/V000780/1
Codespace

award
Unique resource identifier
NE/N016211/1
Codespace

award
Unique resource identifier
NE/N018095/1
Codespace

award
Unique resource identifier
NE/N015932/1
Codespace

award
Other citation details

Please cite this item as: Workman, E., Yang, M., Bell, T., Dong, Y., Jones, A., Fisher, R., France, J., & Linse, K. (2024). Sea-air methane fluxes measured using an eddy-covariance technique on RRS James Clark Ross from January 2019 to March 2021 (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/c9ed4746-f104-4117-ba60-174c5275e2fe

Credit

No credit.
Status
Completed
Point of contact
Organisation name Individual name Electronic mail address Role
British Antarctic Survey Workman, Evelyn Author
Plymouth Marine Laboratory Yang, Mingxi Author
Plymouth Marine Laboratory Bell, Thomas Author
University of East Anglia Dong, Yuanxu Author
British Antarctic Survey Jones, Anna Author
Royal Holloway University of London Fisher, Rebecca Author
Royal Holloway University of London France, James Author
British Antarctic Survey Linse, Katrin Author
NERC EDS UK Polar Data Centre

PDCServiceDesk@bas.ac.uk

Point of contact
Maintenance and update frequency
As needed
Maintenance note
Completed
Global Change Master Directory (GCMD) Science Keywords
Theme

  • Picarro

  • methane

  • polar oceans

  • sea-air flux
Place

  • Scotia Sea Southern Ocean

  • Weddell Sea

  • Drake Passage Southern Ocean

  • South Scotia Ridge Southern Ocean

  • South Sandwich Trench Southern Ocean

  • Bellingshausen Sea

  • South Shetland Islands

  • South Georgia Island

  • Atlantic Ocean

  • Barents Sea

  • Greenland Sea Arctic Ocean

  • Norwegian Sea

  • Svalbard

GEMET - INSPIRE themes, version 1.0
Access constraints
Other restrictions
Other constraints
no limitations to public access
Access constraints
Other restrictions
Other constraints
no limitations
Use constraints
License
Other constraints
Open Government Licence v3.0
Use constraints
Other restrictions
Other constraints

This data is governed by the NERC Data Policy: https://www.ukri.org/who-we-are/nerc/our-policies-and-standards/nerc-data-policy/

Use constraints
Other restrictions
Other constraints

This data is governed by the NERC data policy and supplied under Open Government Licence v.3
Use constraints
Other restrictions
Other constraints

None.
Unique resource identifier
url
Codespace

url
Association Type
Cross reference
Unique resource identifier
url
Codespace

url
Association Type
Cross reference
Unique resource identifier
url
Codespace

url
Association Type
Cross reference
Unique resource identifier
url
Codespace

url
Association Type
Cross reference
Unique resource identifier
url
Codespace

url
Association Type
Cross reference
Unique resource identifier
url
Codespace

url
Association Type
Cross reference
Unique resource identifier
url
Codespace

url
Association Type
Cross reference
Unique resource identifier
url
Codespace

url
Association Type
Cross reference
Spatial representation type
Text, table
Language
English
Character set
UTF8
Topic category
  • Oceans
N
S
E
W
thumbnail




Begin date
2019-01-06
End date
2019-02-17
Supplemental Information

It is recommended that careful attention be paid to the contents of any data, and that the author be contacted with any questions regarding appropriate use. If you find any errors or omissions, please report them to polardatacentre@bas.ac.uk.

Title

European Petroleum Survey Group (EPSG) Geodetic Parameter Registry
Date (Publication)
2008-11-12
Cited responsible party
Organisation name Individual name Electronic mail address Role

European Petroleum Survey Group

EPSGadministrator@iogp.org

Publisher
Unique resource identifier
urn:ogc:def:crs:EPSG::3031
Version

6.18.3

Distributor

Distributor contact
Organisation name Individual name Electronic mail address Role
NERC EDS UK Polar Data Centre

PDCServiceDesk@bas.ac.uk

Distributor
Distributor format
Name Version
text/plain
text/csv
Units of distribution

bytes
Transfer size
523264
OnLine resource
Protocol Linkage Name

WWW:LINK-1.0-http--link

 		http://ramadda.data.bas.ac.uk/repository/entry/show?entryid=c9ed4746-f104-4117-ba60-174c5275e2fe

Get Data
Units of distribution

bytes
Transfer size
523264
OnLine resource
Protocol Linkage Name

WWW:LINK-1.0-http--link

 		http://ramadda.data.bas.ac.uk/repository/entry/show?entryid=c9ed4746-f104-4117-ba60-174c5275e2fe

Get Data
Hierarchy level
Dataset
Statement

Methodology:

The eddy-covariance sea-air methane flux data was collected on the RRS James Clark Ross during cruises JR18004, JR18005, JR18006, JR18007, JR19001, JR19002, and during periods 15/11/2020 - 30/11/2020 and 02/12/2020 - 23/03/2021. The data processing procedure is described: The raw high-frequency wind and CH4 data are processed to calculate fluxes in 20 minute intervals. Related statistics are used for quality control. Linear detrending is employed to identify turbulent fluctuations (w ' and c '). Ship motion is corrected by applying a complementary filtering method using Euler angles which eliminates apparent winds caused by ship movements. The motion-corrected winds are decorrelated against ship motion and double-rotated to account for the wind streamline over the ship. The resulting vertical wind velocity (w) is used to calculate flux. The processed wind data is used to compute variables such as friction velocity and sensible heat flux. CH4 data is despiked, decorrelated against analyser cell pressure and temperature, and decorrelated against factors related to ship motion. A lag (of a few seconds) between CH4 and wind data is addressed using a puff system or the maximum covariance method. The inlet tube, particle filter, and dryer introduce attenuation in CH4 flux signals, which is compensated for in the calculations. Horizontal CH4 fluxes and other statistics are computed for quality control. Finally, the computed fluxes undergo filtering to exclude non-ideal ship manoeuvres or violations of the EC technique requirements. Additionally, the CH4 mixing ratio data was filtered based on wind direction to remove data corresponding to wind coming from behind the ship to remove sources of pollution from the ship stack. 20 minute intervals that pass the QA/QC (Quality Assurance/Quality Control) are further averaged to 2 hours to reduce noise.

Data collection:

Data was collected using a eddy-covariance system installed on the JCR. The system was located at the top of the foremast (approximately 20 m a.m.s.l). The system comprises of a Picarro G2311-f greenhouse gas analyser, a three-dimensional sonic anemometer (Metek Inc., Sonic-3 Scientific) and a motion sensor (initially Systron Donner Motionpak II, which was replaced by 169 a Life Performance-Research LPMS-RS232AL2 in April 2019). Python 3 is used to analyse the data and create the dataset.

Data quality:

QA/QC filters used are:



Basic CH4 flux filtering: same filtering for wind direction and ship movement as for CO2 flux (Dong et al, 2021), then filter data based on these stats within 20min window:



CH4(range) < 0.02ppm



CH4(sdev) < 0.0014ppm



abs(CH4(slope)) < 0.02ppm/hr



Finally remove flux outside of 5 sdev and average to 2hr intervals (retaining 2hr periods with at least 4 good flux segments).





Missing flux data is due to quality control filtering/instrument not collecting data.

Metadata

File identifier
c9ed4746-f104-4117-ba60-174c5275e2fe XML
Metadata language
English
Character set
UTF8
Hierarchy level
Dataset
Hierarchy level name

dataset
Date stamp
2024-01-10
Metadata standard name

ISO 19115 Geographic Information - Metadata
Metadata standard version

ISO 19115:2003(E)
Metadata author
Organisation name Individual name Electronic mail address Role
NERC EDS UK Polar Data Centre

polardatacentre@bas.ac.uk

Point of contact
 
 

Overviews

Spatial extent

thumbnail

Keywords

Picarro methane polar oceans sea-air flux
GEMET - INSPIRE themes, version 1.0

Atmospheric conditions Oceanographic geographical features
Global Change Master Directory (GCMD) Science Keywords

EARTH SCIENCE > Atmosphere > Atmospheric Chemistry/Carbon and Hydrocarbon Compounds > Methane EARTH SCIENCE > Oceans > Ocean Chemistry


Provided by

Share on social sites

Access to the catalogue