ICOADS 1 Degree
Due to a format switch from ASCII to BUFR on November 1, 2016 for drifting buoys, many reports were not processed for November. NCEP was able to recover many of the BUFR data, but NCEI was unable to fulfill gaps with its stream. This left the November files short of their normal number of drifting buoy reports, affecting downstream ICOADS users. Some reports will be recovered at a later date and a reprocess will be needed. This could take place in January or February and coordination between NCEP, NCEI, NCAR will be needed. December 2016 data is back to normal numbers and no issues are expected from that data month.
- The International Comprehensive Ocean-Atmosphere Data Set (ICOADS) is the most extensive collection of surface marine data spanning the past three centuries, together with simple gridded monthly summary products extending from 1800 forward.
- Monthly values for 1960/01 - 2014/12.
- Preliminary monthly values for 2015/01 - 2017/09
- IMPORTANT: The time period of these products is defined in two segments.
- Release 3.0 1960 through 2014
- Following the Release 3.0 end date data are based exclusively on blended NCEP-NCEI near-real-time GTS data with minimal quality control. These data should be considered preliminary and will be subject to change in new releases.
- 1.0 degree latitude x 1.0 degree longitude equatorial grid (21x360).
- 10.0N - 10.0S, 0.5E - 359.5E.
- 1.0 degree latitude x 1.0 degree longitude global grid (180x360).
- 89.5N - 89.5S, 0.5E - 359.5E.
- Sea Surface
- Irregular (dependent on project resources and data availability considerations)
- Monthly (preliminary segment)
|Variable||Statistic||Level||Download File||Create Plot/Subset|
|Sea Surface Temperature (S)||Multiple||Surface||sst.*.nc|
|Air Temperature (A)||Multiple||Surface||air.*.nc|
|Scalar Wind (W)||Multiple||Surface||wspd.*.nc|
|Sea Level Pressure (P)||Multiple||Surface||slp.*.nc|
|Specific Humidity (Q)||Multiple||Surface||shum.*.nc|
|Relative Humidity (R)||Multiple||Surface||rhum.*.nc|
|Sea-air Temperature difference (S-A)||Multiple||Surface||smina.*.nc|
|Sensible Heat Parameter ([S-A]*W)||Multiple||Surface||sflx.*.nc|
|Sat Sp Hum at SST minus Sp Hum (Qs-Q)||Multiple||Surface||qsminq.*.nc|
|Latent Heat Parameter ([Qs-Q]*W)||Multiple||Surface||lflx.*.nc|
|U-wind Stress (U*W)||Multiple||Surface||upstr.*.nc|
|V-wind Stress (V*W)||Multiple||Surface||vpstr.*.nc|
|Sensible Heat Trans Eastward Param (U*A)||Multiple||Surface||uairt.*.nc|
|Sensible Heat Trans Northward Param (V*A)||Multiple||Surface||vairt.*.nc|
|Latent Heat Trans Eastward Param (U*Q)||Multiple||Surface||uspeh.*.nc|
|Latent Heat Trans Northward Param (V*Q)||Multiple||Surface||vspeh.*.nc|
|Zonal Latent Heat Parameter (U*[Qs-Q])||Multiple||Surface||ulflx.*.nc|
|Meridional Latent Heat Parameter (V*[Qs-Q])||Multiple||Surface||vlflx.*.nc|
|Scalar Wind cubed (W*W*W)||Multiple||Surface||wspd3.*.nc|
|Variable||Statistic||Level||Download File||Create Plot/Subset|
|Multiple||Third Sextile (Median)||Surface||*.sextile3.nc|
|Multiple||Number of Observations||Surface||*.nobs.nc|
|Multiple||Mean Day of Month of Observations||Surface||*.mean_day.nc|
|Multiple||Fraction of Observations in Daylight||Surface||*.day_fraction.nc|
|Multiple||Mean Longitude (Off SW Corner of Box) of Observations||Surface||*.mean_lon.nc|
|Multiple||Mean Latitude (Off SW Corner of Box) of Observations||Surface||*.mean_lat.nc|
The netCDF files are subdivided into "standard" and "enhanced" products, which reflect the "trimming" (quality control) procedure used and the data mixture. In the standard products, the data have been edited using climatological 3.5 standard-deviation (sigma) limits, with the observations limited (as nearly as practical) to those from ships. In the "enhanced" products, in contrast, the data have been edited using broader 4.5 sigma limits to better represent extreme climate events, with observations from ships plus from other in situ marine platform types (e.g., drifting and moored buoys).
The netCDF files are further subdivided by spatial domain, with the 1°x1° summaries available in global and equatorial formats. The equatorial products cover the latitude band 10.5°N to 10.5°S, and are global with respect to longitude. In contrast to the global 1°x1° boxes, the equatorial 1°x1° boxes are shifted half a degree in latitude (only) in comparison to the global domain, such that the center-latitude of the central row of boxes is the equator (e.g., 0-1°E, 0.5°S-0.5°N). Both the global and equatorial formats have a standard and enhanced product.
Please refer to the ICOADS Website for more information about the ICOADS project, observational and summary products, and associated metadata.
- Small numerical biases in previous netCDF files are described here.
- var.stat.nc (In directory: /Datasets/icoads/1degree/)
Dataset Format and Size:
- PSD standard NetCDF >8 Mbyte file for each equatorial file (packed).
- PSD standard NetCDF >17 Mbyte file for each equatorial wspd3 file.
- PSD standard NetCDF >74 Mbyte file for each global file (packed).
- PSD standard NetCDF >149 Mbyte file for each global wspd3 file.
- Missing data is flagged with a value of 32766s.
- Missing data is flagged with a value of -9.96921e+36f.
- Please note: If you acquire ICOADS data products from PSD, we ask that you acknowledge us in your use of the data. This may be done by including text such as ICOADS data provided by the NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, from their Web site at http://www.esrl.noaa.gov/psd/ in any documents or publications using these data. We would also appreciate receiving a copy of the relevant publications. This will help PSD to justify keeping the ICOADS data set freely available online in the future. Thank you!
- Please refer to the ICOADS Website Publications page.
- Multinational. The US contribution is the result of a cooperative project between the National Oceanic and Atmospheric Administration (NOAA)--specifically its Earth System Research Laboratory (ESRL), its National Centers for Environmental Information (NCEI), and the Cooperative Institute for Research in Environmental Sciences (CIRES), conducted jointly with the University of Colorado--and the National Science Foundation's National Center for Atmospheric Research (NCAR).
- NetCDF questions:
Physical Sciences Division: Data Management
Boulder, CO 80305-3328
- Data questions:
Eric Freeman, Team STG, Inc./ERT
NOAA National Centers for Environmental Information (NCEI)
Center for Coasts, Oceans and Geophysics (CCOG)
151 Patton Avenue
Asheville, NC 28801-5001 USA
Phone: +1 828-271-4463 (Fax: -4022)