ERDDAP > info > bcodmo_dataset_986866_v1

Grid DAP Data	Sub- set	Table DAP Data	Make A Graph	W M S	Source Data Files	Acces- sible	Title	Sum- mary	FGDC, ISO, Metadata	Back- ground Info	RSS	E mail	Institution	Dataset ID
		data	graph		files	public	[Water column methane, methane oxidation, and pmoA gene copies] - Water column methane, methane oxidation, and pmoA gene copies above southern California methane seeps determined from samples collected on R/V Atlantis cruise AT50-12 in July 2023 (Collaborative Research: Redefining the footprint of deep ocean methane seepage for benthic ecosystems)		F   I   M	background			BCO-DMO	bcodmo_dataset_986866_v1

The Dataset's Variables and Attributes

Row Type	Variable Name	Attribute Name	Data Type	Value
attribute	NC_GLOBAL	cdm_data_type	String	Other
attribute	NC_GLOBAL	Conventions	String	COARDS, CF-1.6, ACDD-1.3
attribute	NC_GLOBAL	creator_email	String	info at bco-dmo.org
attribute	NC_GLOBAL	creator_name	String	BCO-DMO
attribute	NC_GLOBAL	creator_url	String	https://www.bco-dmo.org/
attribute	NC_GLOBAL	defaultDataQuery	String	&time<now
attribute	NC_GLOBAL	doi	String	10.26008/1912/bco-dmo.986866.1
attribute	NC_GLOBAL	Easternmost_Easting	double	-117.7765
attribute	NC_GLOBAL	geospatial_lat_max	double	33.8003
attribute	NC_GLOBAL	geospatial_lat_min	double	32.8339
attribute	NC_GLOBAL	geospatial_lat_units	String	degrees_north
attribute	NC_GLOBAL	geospatial_lon_max	double	-117.7765
attribute	NC_GLOBAL	geospatial_lon_min	double	-118.6488
attribute	NC_GLOBAL	geospatial_lon_units	String	degrees_east
attribute	NC_GLOBAL	infoUrl	String	https://osprey.bco-dmo.org/dataset/986866
attribute	NC_GLOBAL	institution	String	BCO-DMO
attribute	NC_GLOBAL	license	String	The data may be used and redistributed for free but is not intended for legal use, since it may contain inaccuracies. Neither the data Contributor, ERD, NOAA, nor the United States Government, nor any of their employees or contractors, makes any warranty, express or implied, including warranties of merchantability and fitness for a particular purpose, or assumes any legal liability for the accuracy, completeness, or usefulness, of this information.
attribute	NC_GLOBAL	Northernmost_Northing	double	33.8003
attribute	NC_GLOBAL	sourceUrl	String	(local files)
attribute	NC_GLOBAL	Southernmost_Northing	double	32.8339
attribute	NC_GLOBAL	summary	String	Marine methane (CH₄) seeps are dynamic biogeochemical systems that modulate carbon cycling and support high-biomass communities through microbial methane (CH₄) oxidation. While most CH₄ is consumed anaerobically in sediments, a fraction enters the water column, where aerobic methanotrophs form a biological filter limiting CH₄ flux to the atmosphere. However, the extent to which this microbial activity and CH₄ influence extend beyond visibly active seep zones remains poorly constrained, with implications for deep-sea food webs, biogeochemical gradients, and carbon cycling. We investigated CH₄ dynamics and methanotroph distribution across three seep sites on the Southern California margin (Del Mar, Santa Monica (800 meters) Mound, Lasuen Knoll; ~400–1200 meters depth). Using radiotracer (³H-CH₄) incubations, CH₄ concentration profiling, and particulate methane monooxygenase (pmoA) gene quantification, we sampled vertical and horizontal transects and near-bottom waters via the HOV Alvin. CH₄ oxidation was active not only within seep plumes but also in off-seep regions, with the highest rate (454 nanomoles per liter per day) observed within a CH₄-rich bubble plume. pmoA gene abundances remained relatively stable across both seep and off-seep waters, suggesting a persistent CH₄-oxidizing potential. These findings support an expanded "methanosphere," a CH₄-influenced microbial zone shaped by physical transport and environmental gradients. This dataset is part of a PhD thesis: Klonicki-Ference, Emily F. "Microbial Regulation of Methane and Redox Dynamics in the Water Column: From a Proterozoic Ocean Analog to Modern Marine Seeps." PhD diss., University of California, Los Angeles, 2025.
attribute	NC_GLOBAL	time_coverage_end	String	2023-07-26T15:45:00Z
attribute	NC_GLOBAL	time_coverage_start	String	2023-07-17T16:50:00Z
attribute	NC_GLOBAL	title	String	[Water column methane, methane oxidation, and pmoA gene copies] - Water column methane, methane oxidation, and pmoA gene copies above southern California methane seeps determined from samples collected on R/V Atlantis cruise AT50-12 in July 2023 (Collaborative Research: Redefining the footprint of deep ocean methane seepage for benthic ecosystems)
attribute	NC_GLOBAL	Westernmost_Easting	double	-118.6488
variable	Date_UTC		String
attribute	Date_UTC	long_name	String	Date_utc
attribute	Date_UTC	units	String	unitless
variable	CTD_Start_Time_or_Alvin_Niskin_Closure_UTC		String
attribute	CTD_Start_Time_or_Alvin_Niskin_Closure_UTC	long_name	String	Ctd_start_time_or_alvin_niskin_closure_utc
attribute	CTD_Start_Time_or_Alvin_Niskin_Closure_UTC	units	String	unitless
variable	time		double
attribute	time	_CoordinateAxisType	String	Time
attribute	time	actual_range	double	1.6896126E9, 1.6903863E9
attribute	time	axis	String	T
attribute	time	ioos_category	String	Time
attribute	time	long_name	String	Iso_datetime_utc
attribute	time	standard_name	String	time
attribute	time	time_origin	String	01-JAN-1970 00:00:00
attribute	time	units	String	seconds since 1970-01-01T00:00:00Z
variable	Site_Name		String
attribute	Site_Name	long_name	String	Site_name
attribute	Site_Name	units	String	unitless
variable	CTD_or_Alvin_Sample_Number		String
attribute	CTD_or_Alvin_Sample_Number	long_name	String	Ctd_or_alvin_sample_number
attribute	CTD_or_Alvin_Sample_Number	units	String	unitless
variable	Waypoint		int
attribute	Waypoint	actual_range	int	1, 10
attribute	Waypoint	long_name	String	Waypoint
attribute	Waypoint	units	String	unitless
variable	latitude		float
attribute	latitude	_CoordinateAxisType	String	Lat
attribute	latitude	actual_range	float	32.8339, 33.8003
attribute	latitude	axis	String	Y
attribute	latitude	ioos_category	String	Location
attribute	latitude	long_name	String	Latitude
attribute	latitude	standard_name	String	latitude
attribute	latitude	units	String	degrees_north
variable	longitude		float
attribute	longitude	_CoordinateAxisType	String	Lon
attribute	longitude	actual_range	float	-118.6488, -117.7765
attribute	longitude	axis	String	X
attribute	longitude	ioos_category	String	Location
attribute	longitude	long_name	String	Longitude
attribute	longitude	standard_name	String	longitude
attribute	longitude	units	String	degrees_east
variable	Water_Depth		int
attribute	Water_Depth	actual_range	int	2, 1045
attribute	Water_Depth	long_name	String	Water_depth
attribute	Water_Depth	units	String	meters below sea level (mbsl)
variable	Methane		float
attribute	Methane	actual_range	float	32.69, 249228.0
attribute	Methane	long_name	String	Methane
attribute	Methane	units	String	nanomoles per liter (nmol L-1)
variable	Methane_oxidation_Replicate_1		float
attribute	Methane_oxidation_Replicate_1	actual_range	float	0.0, 392.06
attribute	Methane_oxidation_Replicate_1	long_name	String	Methane_oxidation_replicate_1
attribute	Methane_oxidation_Replicate_1	units	String	nanomoles per liter per day (nmol L-1 d-1)
variable	Methane_oxidation_Replicate_2		float
attribute	Methane_oxidation_Replicate_2	actual_range	float	0.009, 376.731
attribute	Methane_oxidation_Replicate_2	long_name	String	Methane_oxidation_replicate_2
attribute	Methane_oxidation_Replicate_2	units	String	nanomoles per liter per day (nmol L-1 d-1)
variable	Methane_oxidation_Replicate_3		float
attribute	Methane_oxidation_Replicate_3	actual_range	float	0.0, 593.979
attribute	Methane_oxidation_Replicate_3	long_name	String	Methane_oxidation_replicate_3
attribute	Methane_oxidation_Replicate_3	units	String	nanomoles per liter per day (nmol L-1 d-1)
variable	pmoA_gene_copy_number		float
attribute	pmoA_gene_copy_number	actual_range	float	2.5, 6.05
attribute	pmoA_gene_copy_number	long_name	String	Pmoa_gene_copy_number
attribute	pmoA_gene_copy_number	units	String	Log pmoA copies per liter

The information in the table above is also available in other file formats (.csv, .htmlTable, .itx, .json, .jsonlCSV1, .jsonlCSV, .jsonlKVP, .mat, .nc, .nccsv, .tsv, .xhtml) via a RESTful web service.