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| Dataset Title: | [GN01 Dissolved Fe(II)] - Dissolved Fe(II) from the southbound leg of the US GEOTRACES Arctic cruise (HLY1502) on USCGC Healy from August to October 2015 (U. S. Arctic GEOTRACES Study) 
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| Institution: | BCO-DMO (Dataset ID: bcodmo_dataset_811614) |
| Information: | Summary
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| FGDC
| ISO 19115
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Attributes {
s {
Station_ID {
Byte _FillValue 127;
String _Unsigned "false";
Byte actual_range 38, 66;
String bcodmo_name "station";
String description "Station number";
String long_name "Station ID";
String units "unitless";
}
Start_Date_UTC {
Int32 _FillValue 2147483647;
Int32 actual_range 20150910, 20151008;
String bcodmo_name "date";
String description "Date at start of sampling; format: YYYYMMDD";
String long_name "Start Date UTC";
String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/ADATAA01/";
String units "unitless";
}
time {
String _CoordinateAxisType "Time";
Float64 actual_range 1.44184728e+9, 1.4442675e+9;
String axis "T";
String bcodmo_name "ISO_DateTime_UTC";
String description "Date and time (UTC) at start of sampling; format: YYYY-MM-DDThh:mm:ss.ssZ";
String ioos_category "Time";
String long_name "Start Time UTC";
String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/DTUT8601/";
String source_name "Start_Time_UTC";
String standard_name "time";
String time_origin "01-JAN-1970 00:00:00";
String time_precision "1970-01-01T00:00:00.00Z";
String units "seconds since 1970-01-01T00:00:00Z";
}
End_Date_UTC {
Int32 _FillValue 2147483647;
Int32 actual_range 20150910, 20151008;
String bcodmo_name "date";
String description "Date at end of sampling; format: YYYYMMDD";
String long_name "End Date UTC";
String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/ADATAA01/";
String units "unitless";
}
End_Time_UTC {
String bcodmo_name "ISO_DateTime_UTC";
String description "Date and time (UTC) at end of sampling; format: YYYY-MM-DDThh:mm:ss.ssZ";
String long_name "End Time UTC";
String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/DTUT8601/";
String units "unitless";
}
latitude {
String _CoordinateAxisType "Lat";
Float64 _FillValue NaN;
Float64 actual_range 71.999, 87.824;
String axis "Y";
String bcodmo_name "latitude";
Float64 colorBarMaximum 90.0;
Float64 colorBarMinimum -90.0;
String description "Latitude at start of sampling";
String ioos_category "Location";
String long_name "Latitude";
String nerc_identifier "https://vocab.nerc.ac.uk/collection/P09/current/LATX/";
String source_name "Start_Latitude";
String standard_name "latitude";
String units "degrees_north";
}
longitude {
String _CoordinateAxisType "Lon";
Float64 _FillValue NaN;
Float64 actual_range -162.5408, -147.8504;
String axis "X";
String bcodmo_name "longitude";
Float64 colorBarMaximum 180.0;
Float64 colorBarMinimum -180.0;
String description "Longitude at start of sampling";
String ioos_category "Location";
String long_name "Longitude";
String nerc_identifier "https://vocab.nerc.ac.uk/collection/P09/current/LONX/";
String source_name "Start_Longitude";
String standard_name "longitude";
String units "degrees_east";
}
End_Latitude {
Float32 _FillValue NaN;
Float32 actual_range 0.0, 87.827;
String bcodmo_name "latitude";
Float64 colorBarMaximum 90.0;
Float64 colorBarMinimum -90.0;
String description "Latitude at end of sampling";
String long_name "Latitude";
String nerc_identifier "https://vocab.nerc.ac.uk/collection/P09/current/LATX/";
String standard_name "latitude";
String units "degrees North";
}
End_Longitude {
Float32 _FillValue NaN;
Float32 actual_range -162.5004, 0.0;
String bcodmo_name "longitude";
Float64 colorBarMaximum 180.0;
Float64 colorBarMinimum -180.0;
String description "Longitude at end of sampling";
String long_name "Longitude";
String nerc_identifier "https://vocab.nerc.ac.uk/collection/P09/current/LONX/";
String standard_name "longitude";
String units "degrees East";
}
Event_ID {
Int16 _FillValue 32767;
Int16 actual_range 6249, 6491;
String bcodmo_name "event";
String description "Event number";
String long_name "Event ID";
String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/EVTAGFL/";
String units "unitless";
}
Sample_ID {
Int16 _FillValue 32767;
Int16 actual_range 11351, 12314;
String bcodmo_name "sample";
String description "GEOTRACES sample number";
String long_name "Sample ID";
String nerc_identifier "https://vocab.nerc.ac.uk/collection/P02/current/ACYC/";
String units "unitless";
}
depth {
String _CoordinateAxisType "Height";
String _CoordinateZisPositive "down";
Float64 _FillValue NaN;
Float64 actual_range 0.0, 3792.0;
String axis "Z";
String bcodmo_name "depth";
String description "Sample depth";
String ioos_category "Location";
String long_name "Sample Depth";
String nerc_identifier "https://vocab.nerc.ac.uk/collection/P09/current/DEPH/";
String positive "down";
String standard_name "depth";
String units "m";
}
Fe_II_D_CONC_BOTTLE_07ordp {
Float32 _FillValue NaN;
Float32 actual_range 0.0, 0.54;
String bcodmo_name "trace_element_conc";
String description "Concentration of dissolved Fe(II) from bottle samples";
String long_name "Fe II D CONC BOTTLE 07ordp";
String units "nanomoles per kilogram (nmol/kg)";
}
SD1_Fe_II_D_CONC_BOTTLE_07ordp {
Float32 _FillValue NaN;
Float32 actual_range 0.0, 0.08375;
String bcodmo_name "trace_element_conc";
String description "One standard deviation of Fe_II_D_CONC_BOTTLE_07ordp";
String long_name "SD1 Fe II D CONC BOTTLE 07ordp";
String units "nanomoles per kilogram (nmol/kg)";
}
Flag_Fe_II_D_CONC_BOTTLE_07ordp {
Byte _FillValue 127;
String _Unsigned "false";
Byte actual_range 2, 6;
String bcodmo_name "q_flag";
Float64 colorBarMaximum 150.0;
Float64 colorBarMinimum 0.0;
String description "Quality flag for Fe_II_D_CONC_BOTTLE_07ordp";
String long_name "Flag Fe II D CONC BOTTLE 07ordp";
String units "unitless";
}
Fe_II_D_CONC_ICE {
String bcodmo_name "trace_element_conc";
String description "Concentration of dissolved Fe(II) from ice samples";
String long_name "Fe II D CONC ICE";
String units "nanomoles per kilogram (nmol/kg)";
}
SD1_Fe_II_D_CONC_ICE {
Float32 _FillValue NaN;
Float32 actual_range 0.0013, 0.01308;
String bcodmo_name "trace_element_conc";
String description "One standard deviation of Fe_II_D_CONC_ICE";
String long_name "SD1 Fe II D CONC ICE";
String units "nanomoles per kilogram (nmol/kg)";
}
Flag_Fe_II_D_CONC_ICE {
Byte _FillValue 127;
String _Unsigned "false";
Byte actual_range 2, 2;
String bcodmo_name "q_flag";
Float64 colorBarMaximum 150.0;
Float64 colorBarMinimum 0.0;
String description "Quality flag for Fe_II_D_CONC_ICE";
String long_name "Flag Fe II D CONC ICE";
String units "unitless";
}
Fe_II_D_CONC_BOAT_PUMP_wfzk5t {
Float32 _FillValue NaN;
Float32 actual_range 0.0, 0.01465;
String bcodmo_name "trace_element_conc";
String description "Concentration of dissolved Fe(II) from boat pump samples";
String long_name "Fe II D CONC BOAT PUMP Wfzk5t";
String units "nanomoles per kilogram (nmol/kg)";
}
SD1_Fe_II_D_CONC_BOAT_PUMP_wfzk5t {
Float32 _FillValue NaN;
Float32 actual_range 0.0, 0.001;
String bcodmo_name "trace_element_conc";
String description "One standard deviation of Fe_II_D_CONC_BOAT_PUMP_wfzk5t";
String long_name "SD1 Fe II D CONC BOAT PUMP Wfzk5t";
String units "nanomoles per kilogram (nmol/kg)";
}
Flag_Fe_II_D_CONC_BOAT_PUMP_wfzk5t {
Byte _FillValue 127;
String _Unsigned "false";
Byte actual_range 6, 6;
String bcodmo_name "q_flag";
Float64 colorBarMaximum 150.0;
Float64 colorBarMinimum 0.0;
String description "Quality flag for Fe_II_D_CONC_BOAT_PUMP_wfzk5t";
String long_name "Flag Fe II D CONC BOAT PUMP Wfzk5t";
String units "unitless";
}
Sample_Type {
String bcodmo_name "sample_type";
String description "Sample type";
String long_name "Sample Type";
String units "unitless";
}
Notes {
String bcodmo_name "comment";
String description "Notes/comments";
String long_name "Notes";
String units "unitless";
}
}
NC_GLOBAL {
String access_formats ".htmlTable,.csv,.json,.mat,.nc,.tsv,.esriCsv,.geoJson,.odvTxt";
String acquisition_description
"Samples for in-situ dissolved Fe(II) (dFe(II)) detection (see Supplemental
Files: Table 1 and Figure 1):
157 samples were as soon as possible analysed from the Geotraces carousel
from Stn 38-66;
5 ice samples from Stn43 /46\\u00a0(operated by Ana Aguilar, Rob Rember);
3 small boat surface samples from Stan60,61,66\\u00a0(operated by Ana
Aguilar, Rob Rember);
1 Multicorer niskin sample from Stn66\\u00a0(operated by Greg Cutter).
Shipboard measurements were performed by Dr. Maija I. Heller for Fe(II)
following a method by King et al. The photomultiplier (PMT) for analysis was
borrowed from the FS Polarstern (Germany) at the North Pole from scientist
Micha Rijkenberg, NIOZ, (Netherlands) since the PMT owned by UCSC (USA) was
damaged at the beginning of the cruise, likely due to a bad power supply.
Dissolved Fe(II) concentrations were determined using an automated flow
injection analysis system (FeLume II Waterville Analytical) employing a
luminol chemiluminescence based detection system (King et al, 1995). Luminol,
prepared in 18.2 MO Milli-Q water and buffered to pH 10.3 with ultra pure
ammonia (here used quartz distilled at UCSC), reacts with an Fe(II)-
containing solution, resulting in luminol oxidation with concurrent
chemiluminescent emission (Rose & Waite, 2001; Croot & Laan, 2002). The FeLume
was fitted with a standard quartz flow cell and a Hamamatsu HC135 photon
counter configured with the following settings: flow rate: 2.5 mL per minute;
photon counter integration time: 200 ms; load time: 20\\u201340 s. The mixing
and reaction occur in a spiral flow cell positioned in front of a
photomultiplier tube. The sample and luminol reagent were directly continually
mixed in the flow cell by omitting the injection valve (Rose & Waite, 2001;
Hopkinson & Barbeau, 2007; Roy et al, 2008). Once the signal was in steady-
state, the mean of the last 50 data points was used to determine the signal.
Fe(II) was quantified by 6-8 standard additions of Fe(II) (typically 0.025,
0.05, 0.1, 0.2, 0.4 and 0.8 nM) to samples of seawater which were stored in
the dark for several days and showed low initial signals for Fe(II). A 0.01 M
Fe(II) stock solution was prepared with ferrous sulfate (Sigma) in 0.2 M HCl.
A working Fe(II) standard solution (100 nM) was prepared daily. Detection
limits were determined for dark corrected aged seawater samples where ferrous
Fe was negligible based on a standard 3r evaluation of the baseline signal
(Moffett, et al. 2007; Kondo & Moffett, 2013; Heller et al., 2017).
Instrumentation:
The chemiluminescence was detected with a Hamamatsu HC135 Photon counter
build into a flow injection system (FeLume, Waterville Analytical, US)
borrowed from NIOZ (Netherlands) as described above (Rijkenberg et al., 2014).
Problem Report:
The required PMT for analysis was borrowed from the FS Polarstern (Germany)
at the North Pole from NIOZ scientist Micha Rijkenberg, (Netherlands), since
the PMT owned by UCSC (USA) was damaged at the very beginning of the cruise,
most likely by a faulty power supply.";
String awards_0_award_nid "776231";
String awards_0_award_number "OCE-1535854";
String awards_0_data_url "http://www.nsf.gov/awardsearch/showAward.do?AwardNumber=1535854";
String awards_0_funder_name "NSF Division of Ocean Sciences";
String awards_0_funding_acronym "NSF OCE";
String awards_0_funding_source_nid "355";
String awards_0_program_manager "Henrietta N Edmonds";
String awards_0_program_manager_nid "51517";
String awards_1_award_nid "776237";
String awards_1_award_number "OCE-1438977";
String awards_1_data_url "https://www.nsf.gov/awardsearch/showAward?AWD_ID=1438977&HistoricalAwards=false";
String awards_1_funder_name "NSF Division of Ocean Sciences";
String awards_1_funding_acronym "NSF OCE";
String awards_1_funding_source_nid "355";
String awards_1_program_manager "Donald L. Rice";
String awards_1_program_manager_nid "51467";
String cdm_data_type "Other";
String comment
"Dissolved Fe(II)
U.S. GEOTRACES Arctic Cruise (GN01) in 2015
PI: Phoebe J. Lam (UC Santa Cruz)
Contact: Maija Heller
Version history:
23-Sep-2020 (v2; current) - corrected duplicate sample and event numbers (refer to Processing Description in metadata);
15-May-2020 (v1) - original.";
String Conventions "COARDS, CF-1.6, ACDD-1.3";
String creator_email "info@bco-dmo.org";
String creator_name "BCO-DMO";
String creator_type "institution";
String creator_url "https://www.bco-dmo.org/";
String data_source "extract_data_as_tsv version 2.3 19 Dec 2019";
String dataset_current_state "Final and no updates";
String date_created "2020-05-15T16:15:26Z";
String date_modified "2020-09-23T16:35:16Z";
String defaultDataQuery "&time<now";
String doi "10.26008/1912/bco-dmo.811614.2";
Float64 Easternmost_Easting -147.8504;
Float64 geospatial_lat_max 87.824;
Float64 geospatial_lat_min 71.999;
String geospatial_lat_units "degrees_north";
Float64 geospatial_lon_max -147.8504;
Float64 geospatial_lon_min -162.5408;
String geospatial_lon_units "degrees_east";
Float64 geospatial_vertical_max 3792.0;
Float64 geospatial_vertical_min 0.0;
String geospatial_vertical_positive "down";
String geospatial_vertical_units "m";
String history
"2024-11-23T16:48:17Z (local files)
2024-11-23T16:48:17Z https://erddap.bco-dmo.org/erddap/tabledap/bcodmo_dataset_811614.html";
String infoUrl "https://www.bco-dmo.org/dataset/811614";
String institution "BCO-DMO";
String instruments_0_acronym "GO-FLO Teflon TM";
String instruments_0_dataset_instrument_nid "811659";
String instruments_0_description "GO-FLO Teflon-lined Trace Metal free sampling bottles are used for collecting water samples for trace metal, nutrient and pigment analysis. The GO-FLO sampling bottle is designed specifically to avoid sample contamination at the surface, internal spring contamination, loss of sample on deck (internal seals), and exchange of water from different depths.";
String instruments_0_instrument_external_identifier "https://vocab.nerc.ac.uk/collection/L05/current/30/";
String instruments_0_instrument_name "GO-FLO Teflon Trace Metal Bottle";
String instruments_0_instrument_nid "533";
String instruments_1_acronym "FIA";
String instruments_1_dataset_instrument_nid "811653";
String instruments_1_description "An instrument that performs flow injection analysis. Flow injection analysis (FIA) is an approach to chemical analysis that is accomplished by injecting a plug of sample into a flowing carrier stream. FIA is an automated method in which a sample is injected into a continuous flow of a carrier solution that mixes with other continuously flowing solutions before reaching a detector. Precision is dramatically increased when FIA is used instead of manual injections and as a result very specific FIA systems have been developed for a wide array of analytical techniques.";
String instruments_1_instrument_external_identifier "https://vocab.nerc.ac.uk/collection/L05/current/LAB36/";
String instruments_1_instrument_name "Flow Injection Analyzer";
String instruments_1_instrument_nid "657";
String instruments_1_supplied_name "FeLume II Waterville Analytical";
String instruments_2_dataset_instrument_nid "811655";
String instruments_2_description "Photon counting is a technique in which individual photons are counted using some single-photon detector (SPD).";
String instruments_2_instrument_name "Photon Counter";
String instruments_2_instrument_nid "811654";
String instruments_2_supplied_name "Hamamatsu HC135";
String instruments_3_dataset_instrument_nid "811657";
String instruments_3_description "An instrument containing a photoelectric cell and a series of electrodes, used to detect and amplify the light from very faint sources.";
String instruments_3_instrument_name "Photomultiplier";
String instruments_3_instrument_nid "811656";
String instruments_3_supplied_name "photomultiplier";
String keywords "07ordp, bco, bco-dmo, biological, boat, bottle, chemical, conc, data, dataset, date, depth, dmo, end, End_Date_UTC, End_Latitude, End_Longitude, End_Time_UTC, erddap, event, Event_ID, Fe_II_D_CONC_BOAT_PUMP_wfzk5t, Fe_II_D_CONC_BOTTLE_07ordp, Fe_II_D_CONC_ICE, flag, Flag_Fe_II_D_CONC_BOAT_PUMP_wfzk5t, Flag_Fe_II_D_CONC_BOTTLE_07ordp, Flag_Fe_II_D_CONC_ICE, ice, latitude, longitude, management, notes, oceanography, office, preliminary, pump, sample, Sample_Depth, Sample_ID, Sample_Type, sd1, SD1_Fe_II_D_CONC_BOAT_PUMP_wfzk5t, SD1_Fe_II_D_CONC_BOTTLE_07ordp, SD1_Fe_II_D_CONC_ICE, start, Start_Date_UTC, station, Station_ID, time, type, wfzk5t";
String license "https://www.bco-dmo.org/dataset/811614/license";
String metadata_source "https://www.bco-dmo.org/api/dataset/811614";
Float64 Northernmost_Northing 87.824;
String param_mapping "{'811614': {'Start_Time_UTC': 'flag - time', 'Sample_Depth': 'flag - depth', 'Start_Longitude': 'flag - longitude', 'Start_Latitude': 'flag - latitude'}}";
String parameter_source "https://www.bco-dmo.org/mapserver/dataset/811614/parameters";
String people_0_affiliation "University of California-Santa Cruz";
String people_0_affiliation_acronym "UC Santa Cruz";
String people_0_person_name "Phoebe J. Lam";
String people_0_person_nid "51146";
String people_0_role "Principal Investigator";
String people_0_role_type "originator";
String people_1_affiliation "University of California-Santa Cruz";
String people_1_affiliation_acronym "UC Santa Cruz";
String people_1_person_name "Maija I. Heller";
String people_1_person_nid "668102";
String people_1_role "Contact";
String people_1_role_type "related";
String people_2_affiliation "Woods Hole Oceanographic Institution";
String people_2_affiliation_acronym "WHOI BCO-DMO";
String people_2_person_name "Shannon Rauch";
String people_2_person_nid "51498";
String people_2_role "BCO-DMO Data Manager";
String people_2_role_type "related";
String project "U.S. GEOTRACES Arctic";
String projects_0_acronym "U.S. GEOTRACES Arctic";
String projects_0_description
"Description from NSF award abstract:
In pursuit of its goal \"to identify processes and quantify fluxes that control the distributions of key trace elements and isotopes in the ocean, and to establish the sensitivity of these distributions to changing environmental conditions\", in 2015 the International GEOTRACES Program will embark on several years of research in the Arctic Ocean. In a region where climate warming and general environmental change are occurring at amazing speed, research such as this is important for understanding the current state of Arctic Ocean geochemistry and for developing predictive capability as the regional ecosystem continues to warm and influence global oceanic and climatic conditions. The three investigators funded on this award, will manage a large team of U.S.scientists who will compete through the regular NSF proposal process to contribute their own unique expertise in marine trace metal, isotopic, and carbon cycle geochemistry to the U.S. effort. The three managers will be responsible for arranging and overseeing at-sea technical services such as hydrographic measurements, nutrient analyses, and around-the-clock management of on-deck sampling activites upon which all participants depend, and for organizing all pre- and post-cruise technical support and scientific meetings. The management team will also lead educational outreach activities for the general public in Nome and Barrow, Alaska, to explain the significance of the study to these communities and to learn from residents' insights on observed changes in the marine system. The project itself will provide for the support and training of a number of pre-doctoral students and post-doctoral researchers. Inasmuch as the Arctic Ocean is an epicenter of global climate change, findings of this study are expected to advance present capability to forecast changes in regional and globlal ecosystem and climate system functioning.
As the United States' contribution to the International GEOTRACES Arctic Ocean initiative, this project will be part of an ongoing multi-national effort to further scientific knowledge about trace elements and isotopes in the world ocean. This U.S. expedition will focus on the western Arctic Ocean in the boreal summer of 2015. The scientific team will consist of the management team funded through this award plus a team of scientists from U.S. academic institutions who will have successfully competed for and received NSF funds for specific science projects in time to participate in the final stages of cruise planning. The cruise track segments will include the Bering Strait, Chukchi shelf, and the deep Canada Basin. Several stations will be designated as so-called super stations for intense study of atmospheric aerosols, sea ice, and sediment chemistry as well as water-column processes. In total, the set of coordinated international expeditions will involve the deployment of ice-capable research ships from 6 nations (US, Canada, Germany, Sweden, UK, and Russia) across different parts of the Arctic Ocean, and application of state-of-the-art methods to unravel the complex dynamics of trace metals and isotopes that are important as oceanographic and biogeochemical tracers in the sea.";
String projects_0_end_date "2017-06";
String projects_0_geolocation "Arctic Ocean; Sailing from Dutch Harbor to Dutch Harbor";
String projects_0_name "U.S. Arctic GEOTRACES Study";
String projects_0_project_nid "638812";
String projects_0_start_date "2014-07";
String publisher_name "Biological and Chemical Oceanographic Data Management Office (BCO-DMO)";
String publisher_type "institution";
String sourceUrl "(local files)";
Float64 Southernmost_Northing 71.999;
String standard_name_vocabulary "CF Standard Name Table v55";
String summary "Dissolved Fe(II) concentrations were determined using an automated flow injection analysis system (FeLume II Waterville Analytical) employing a luminol chemiluminescence based detection system as described in King et al. (1995) and Heller et al. (2017).\\r\\n\\r\\nFrom published and ongoing work in the Peru and Chile oxygen minimum zones an optimized methodology for Fe(II) detection by luminol has been described in Croot et al. (2019). This work details some of the challenges and limitations of using luminol for dFe(II) detection. It should be noted that as Fe(II) is a transient redox species with a short half life in oxygenated seawater that is dependent on dissolved oxygen and pH, it is not possible to archive (preserve) samples for later analysis. Intercalibrations for Fe(II) have yet to be conducted in the context of GEOTRACES studies and should be pursued where logistically possible.";
String time_coverage_end "2015-10-08T01:25:00.00Z";
String time_coverage_start "2015-09-10T01:08:00.00Z";
String title "[GN01 Dissolved Fe(II)] - Dissolved Fe(II) from the southbound leg of the US GEOTRACES Arctic cruise (HLY1502) on USCGC Healy from August to October 2015 (U.S. Arctic GEOTRACES Study)";
String version "2";
Float64 Westernmost_Easting -162.5408;
String xml_source "osprey2erddap.update_xml() v1.5";
}
}
Data Access Protocol (DAP) and its
selection constraints.
The URL specifies what you want: the dataset, a description of the graph or the subset of the data, and the file type for the response.
Tabledap request URLs must be in the form
https://coastwatch.pfeg.noaa.gov/erddap/tabledap/datasetID.fileType{?query}
For example,
https://coastwatch.pfeg.noaa.gov/erddap/tabledap/pmelTaoDySst.htmlTable?longitude,latitude,time,station,wmo_platform_code,T_25&time>=2015-05-23T12:00:00Z&time<=2015-05-31T12:00:00Z
Thus, the query is often a comma-separated list of desired variable names,
followed by a collection of
constraints (e.g., variable<value),
each preceded by '&' (which is interpreted as "AND").
For details, see the tabledap Documentation.