Dataset
Arctic Cloud Summer Expedition (ACSE): composite flux data for Icebreaker Oden
Abstract
This dataset contains provides the final best estimates of fluxes, mean environmental variables and derived transfer coefficient estimates, along with asociated quality control flags, during the Icebreaker Oden voyage durning the Arctic Cloud Summer Expedition (ACSE) in summer 2014. These were calculated based on instrumentation data from the University of Leeds' Metek sonic anemometer, Licor LI-7500 gas analyzer and XSENS MTi-G-700 motion pack, plus mean surface meteorology data provided from the automatic weather station operated on board by the Department of Meteorology, Stockholm University (MISU).
Other data from the UK contribution, as well as selected other data, are available within the associated data collection in the Centre for Environmental Data Analysis (CEDA) archives. Other cruise data may be available in the NOAA ACSE and The Bolin Centre for Climate Research SWERUS (SWEdish-Russian-US) holdings - see online resources linked to this record.
The Arctic Cloud Summer Expedition (ACSE) was a collaboration between the University of Leeds, the University of Stockholm, and NOAA-CIRES. ACSE aimed to study the response of Arctic boundary layer cloud to changes in surface conditions in the Arctic Ocean as a working package of the larger Swedish-Russian-US Investigation of Climate, Cryosphere and Carbon interaction (SWERUS-C3) Expedition in Summer 2014. This expedition was a core component to the overall SWERUS-C3 programme and was supported by the Swedish Polar Research Secretariat.
ACSE took place during a 3-month cruise of the Swedish Icebreaker Oden from Tromso, Norway to Barrow, Alaska and back over the summer of 2014. During this cruise ACSE scientists measured surface turbulent exchange, boundary layer structure, and cloud properties. Many of the measurements used remote sensing approaches - radar, lidar, and microwave radiometers - to retrieve vertical profiles of the dynamic and microphysical properties of the lower atmosphere and cloud.
The UK participation of ACSE was funded by the Natural Environment Research Council (NERC, grant: NE/K011820/1) and involved instrumentation from the Atmospheric Measurement Facility of the UK's National Centre for Atmospheric Science (NCAS AMF). This dataset collection contains data mainy from the UK contribution with some additional data from other institutes also archived to complement the suite of meteorological measurements.
The document "ACSE_turbulent_fluxes_readme.txt" in the archive contains fuller details of the flux calculations. The final data, prepared for archiving as NetCDF data at the Centre for Environmental Data Analysis (CEDA) by Ian Brooks, University of Leeds, contain:
1) The final quality controlled best estimates of 20-min averaged dynamic fluxes, associated mean environmental variables (10m wind, etc), transfer coefficients, and quality control flags.
2) The raw kinematic fluxes, etc that go into generating (1), along with the quality control variables used in generating the QC flags, and the QC flags.
3) Other environmental variables (in some cases with duplicates from multiple different sensors) averaged onto the same time base as the flux estimates.
The authors note that in all cases a lot of work has been done on quality control and applying suitable corrections to raw measurements. In many cases other choices could have been made, and additional QC measures may need to be applied.
Most of the work on the flux data processing has been done by John Prytherch, with additional input from Ian Brooks and Dominic Salisbury. Additional work on ancillary data was undertaken by other members of the ACSE science team.
Details
| Previous Info: |
No news update for this record
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| Previously used record identifiers: |
No related previous identifiers.
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| Access rules: |
Access to these data is available to any registered CEDA user. Please Login or Register for an account to gain access.
Use of these data is covered by the following licence: http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/. When using these data you must cite them correctly using the citation given on the CEDA Data Catalogue record. |
| Data lineage: |
Data were collected, quality controlled and prepared for archiving by the instrument scientists before upload to the Centre for Environmental Data Analysis (CEDA) for long term archiving. |
| Data Quality: |
Data quality control flagging follows the methodology described in: - Foken et al. 2012, Ch4 of 'Eddy Covariance: A Practical Guide to Measurement and Data Analysis', ed. M. Aubinet, T. Vesala, D. Papale; Springer. - Wichura and Foken 1995; Foken and Wichura 1996; and Vickers and Mahrt 1997. Some of the code implementing these was adapted from the EDDY CALC suite: http://www.swissfluxnet.ch/eddycalc/html/Eddycalc_LI7200.html
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| File Format: |
Data are CF-compliant NetCDF formatted
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Related Documents
Process overview
Instrument/Platform pairings
| Output Description | None |
- long_name: 10/L (L = Obukhov length)
- var_id: ToL
- units:
- units: 1e3
- long_name: 10m neutral Dalton number - latent heat exchange coefficient (*1000)
- var_id: CQ10n
- units: 1e3
- long_name: 10m neutral Stanton number - sensible heat exchange coefficient (*1000)
- var_id: CT10n
- units: 1e3
- long_name: 10m neutral Stanton number from SHflux_s - sensible heat exchange coefficient (*1000)
- var_id: CT10n_s
- units: K
- long_name: 10m neutral air temperature (K)
- var_id: ta10n
- units: 1e3
- long_name: 10m neutral drag coefficient (*1000)
- var_id: CD10n
- units: K
- long_name: 10m neutral specific humidity (kg/kg)
- var_id: qa10n
- units: K
- long_name: 10m neutral virtual temperature (K)
- var_id: tv10n
- units: m/s
- long_name: 10m neutral wind speed (m/s)
- var_id: u10n
- units: K
- long_name: Air temperature from 7th deck (25m) weather station (K)
- var_id: Tair_wx
- units: K
- long_name: Air temperature on foremast at 16.5m (K)(from Rotronic)
- var_id: Tair_m2
- units: K
- long_name: Air temperature on foremast at 20m (K)(from Rotronic)
- var_id: Tair_m1
- units: kg/m3
- long_name: Density of dry air (kg/m3)
- var_id: rhoa_mast
- units: kg/m3
- long_name: Density of moist air (kg/m3)
- var_id: rho_mast
- long_name: QC flag for latent heat flux, 1 = good
- var_id: rwflag
- units:
- long_name: QC flag for momentum flux, 1 = good
- var_id: uwflag
- units:
- long_name: QC flag for sensible heat flux from taflux_s, 1 = good
- var_id: twflag_s
- units:
- long_name: QC flag for sensible heat flux, 1 = good
- var_id: twflag
- units:
- units: hPa
- var_id: P
- long_name: air pressure (hPa)(in licor box) at ~17m
- units: K
- long_name: air pressure at mast top (20m) (K)
- var_id: P_mast
- units: K m/s
- long_name: air temperature flux (corrected using licor humidity) (Km/s)
- var_id: taflux
- units: m2/s2
- long_name: along-wind kinematic momentum flux (m2/s2)
- var_id: uwflux
- units: m
- long_name: change in altitude (lift) of mean streamline through sonic anemometer (m)
- var_id: deltaz
- units: m2/s2
- long_name: cross-wind kinematic momentum flux (m2/s2)
- var_id: vwflux
- units: W/m2
- long_name: downwelling longwave (IR) radiation (W/m2)
- var_id: pir_wx
- units: W/m2
- long_name: downwelling longwave used to correct KT15 surface T (W/m2)
- var_id: pir_KT15
- units: W/m2
- long_name: downwelling shortwave (solar) radiation (W/m2)
- var_id: psp_wx
- units: m
- long_name: effective wind measurement height: mast top (20.3m) - deltaz (m)
- var_id: zu
- units: s
- var_id: endtime
- units: %
- long_name: flow distortion % wind speed bias
- var_id: CFDfact
- units: m/s
- var_id: ustar
- long_name: friction velocity (m/s)
- units: degrees
- long_name: horizontal rotation of RWD (from CFD model) wrt free stream flow
- var_id: twist
- units: kg/kg
- long_name: humidity mixing ratio (kg/kg)
- var_id: mixrat
- units: W/m2
- long_name: latent heat flux (W/m2)
- var_id: QHflux
- var_id: lh
- units: J/kg
- long_name: latent heat of vapourisation at surface (J/kg)
- units: degrees
- var_id: lat
- long_name: latitude (deg) from ship navigation system
- units: degrees
- long_name: latitude from 7th deck (25m) weather station (deg)
- var_id: lat_wx
- long_name: licor diagnostic max (AGC gain) good = 240-252
- var_id: diagmax
- units:
- long_name: licor diagnostic mean (AGC gain) good = 240-252
- var_id: diagmn
- units:
- long_name: licor diagnostic min (AGC gain) good = 240-252
- var_id: diagmin
- units:
- units: degrees
- var_id: lon
- long_name: longitude (deg) [-180:0:180] from ship navigation system
- units: degrees
- long_name: longitude from 7th deck (25m) weather station (deg)
- var_id: lon_wx
- units: degrees
- long_name: mean ship pitch (deg)(right handed, +ve bow down)
- var_id: mpitch
- units: degrees
- long_name: mean ship roll (deg)(righ handed, +ve port up)
- var_id: mroll
- units: K
- long_name: mean sonic temperature (K)
- var_id: sontemp
- units: W/m2
- long_name: net longwave (IR) radiation (W/m2)
- var_id: pirn_wx
- units: K
- long_name: potential temperature at mast top (K)
- var_id: tap
- units: hPa
- long_name: pressure from 7th deck (25m) weather station (hPa)
- var_id: P_wx
- units: %
- var_id: rh
- long_name: relative humidity (%) (from licor 7500)
- units: %
- long_name: relative humidity from 7th deck (25m) weather station (%)
- var_id: RH_wx
- units: %
- long_name: relative humidity on foremast at 16.5m (%)(from Rotronic)
- var_id: RH_m2
- units: %
- long_name: relative humidity on foremast at 20m (%)(from Rotronic)
- var_id: RH_m1
- units: degrees
- long_name: relative wind direction (deg from bow)
- var_id: rwd
- units: degrees
- long_name: relative wind direction (deg) from ship sensors
- var_id: rwd_ship
- units: degrees
- long_name: relative wind direction from 7th deck (25m) weather station (deg from bow)
- var_id: rwd_wx
- units: m/s
- long_name: relative wind speed (m/s) from ship sensors
- var_id: rws_ship
- units: m/s
- long_name: relative wind speed (scalar averaged)(m/s)
- var_id: rws_s
- units: m/s
- long_name: relative wind speed (vector averaged)(m/s)
- var_id: rws_v
- units: m/s
- long_name: relative wind speed from 7th deck (25m) weather station (m/s)
- var_id: rws_wx
- units: 1e-3
- long_name: salinity (PSU) from ship pumped intake at 8m depth
- var_id: sal
- units: %
- long_name: sea ice fraction from AMSR-E & ASI method, interpolated to Oden lat/lon/time)
- var_id: ice_amsr
- units: %
- long_name: sea ice fraction from SSMI & ASI method, interpolated to Oden lat/lon/time)
- var_id: ice_ssmi
- units: K
- var_id: sst
- long_name: sea surface temperature (K) from ship pumped intake at 8m depth
- units: W/m2
- long_name: sensible heat flux (W/m2)
- var_id: SHflux
- units: W/m2
- long_name: sensible heat flux (W/m2) from VHflux converted using Smith, 88 bulk LH flux (Persson et al. 2005)
- var_id: SHflux_s
- units: degrees
- var_id: heading
- long_name: ship mean heading (deg)
- units: m/s
- var_id: sog
- long_name: ship mean speed over ground (m/s)
- units: degrees
- var_id: cog
- long_name: ship vector mean course over ground (deg)
- units: degrees
- long_name: solar azimuth angle (deg)
- var_id: solaraz
- units: degrees
- long_name: solar zenith angle (deg)
- var_id: solarzen
- units: K m/s
- long_name: sonic (virtual) temperature flux (Km/s)
- var_id: tsflux
- units: W/m2
- long_name: sonic (virtual) temperature heat flux (W/m2)
- var_id: VHflux
- units: J/(K kg)
- long_name: specific heat capacity of moist air (J/(K kg))
- var_id: cp
- units: kg/kg
- var_id: qair
- long_name: specific humidity (kg/kg) (from licor 7500)
- units: kg/kg
- long_name: specific humidity at mast top (kg/kg)
- var_id: qair_mast
- units: degrees
- long_name: standard deviation of relative wind direction (sonic anem)(deg)
- var_id: rwd_std
- units: m/s
- long_name: standard deviation of relative wind speed (sonic anem)(m/s)
- var_id: rws_std
- units: degrees
- long_name: standard deviation of ship roll (deg)
- var_id: sroll
- units: degrees
- long_name: standard deviation of ships pitch (deg)
- var_id: spitch
- units: degrees
- long_name: standard deviation of true wind direction (sonic anem)(deg)
- var_id: twd_std
- units: s
- var_id: starttime
- units: kg/kg
- long_name: surface specific humidity (kg/kg)
- var_id: qs
- units: K
- var_id: Ts
- long_name: surface temperature (K)
- units: K
- long_name: surface temperature from KT15-1 (K) (corrected for LW reflection)
- var_id: Ts_KT15_1
- units: K
- long_name: surface temperature from KT15-2 (K) (corrected for LW reflection)
- var_id: Ts_KT15_2
- units: degrees
- var_id: tilt
- long_name: tilt of mean streamline from horizontal (deg)
- var_id: time
- units: days
- long_name: time as decimal day of year
- var_id: doy
- units: kg/m3
- long_name: true air temperature from sonic anem. (K)(corrected for humidity)
- var_id: tempair
- units: degrees
- long_name: true wind direction (deg)
- var_id: twd
- units: degrees
- long_name: true wind direction (deg) from ship sensors
- var_id: twd_ship
- units: degrees
- long_name: true wind direction from 7th deck (25m) weather station (deg)
- var_id: twd_wx
- units: m/s
- long_name: true wind speed (m/s) from ship sensors
- var_id: tws_ship
- units: m/s
- long_name: true wind speed (scalar averaged)(m/s)
- var_id: tws_s
- units: m/s
- long_name: true wind speed (vector averaged)(m/s)
- var_id: tws_v
- units: m/s
- long_name: true wind speed from 7th deck (25m) weather station (m/s)
- var_id: tws_wx
- units: kg m/kg s
- long_name: water vapour flux (Licor 7500 humidity) (kg m/kg s)
- var_id: rflux
- long_name: z/L (z = measurement height, L = Obukhov length)
- var_id: zoL
- units:
Co-ordinate Variables
Temporal Range
2014-07-10T13:11:59
2014-10-02T22:48:00
Geographic Extent
85.2300° |
||
-180.0000° |
180.0000° |
|
69.6600° |