ERSST.v3: Extended Reconstructed Sea Surface Temperature Dataset, Version 3
Extended Reconstructed Sea Surface Temperatures, version 3 (ERSST.v3), beginning January
1854.
ERSST.v3 is an improved extended reconstruction over version 2. Most of the improvements are justified
by testing with simulated data. The major differences are caused by the improved low-frequency (LF)
tuning of ERSST.v3 which reduces the SST anomaly damping before 1930 using the optimized parameters.
Beginning in 1985, ERSST.v3 is also improved by explicitly including bias-adjusted satellite infrared
data from AVHRR.
One of the additional changes is that the low frequency 15-year filter uses data centered on the current year.
If some of data for 15-year period has not yet been observed, it can, of course, not be used. However,
with time these data will become available. Thus, there may be slight modifications of recent
ERSST fields with time.
The NetCDF file names are: ersst.yyyymm.nc
The files can be found at: ftp://eclipse.ncdc.noaa.gov/pub/ersst/netcdf/
Each file contains 3 fields for each month. The fields are:
Extended reconstructed sea surface temperature(ERSST), ERSST anomaly,
and Estimated error standard deviation of analyzed_ersst.
The anomalies are computed with respect to a 1971-2000 month climatology.
The climatology is described in
Xue, Y., T. M. Smith, and R. W. Reynolds, 2003: Interdecadal changes of
30-yr SST normals during 1871-2000. J. Climate, 16, 1601-1612.
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You can get the header of the NetCDF file by using a NetCDF program (ncdump).
An example is:
ncdump -h ersst.200708.nc
netcdf ersst.200708 {
dimensions:
time = 1 ;
zlev = 1 ;
lat = 89 ;
lon = 180 ;
variables:
float time(time) ;
time:long_name = "Center time of the day" ;
time:units = "days since 1854-01-15" ;
time:delta_t = "0000-01-00" ;
time:avg_period = "0000-01-00" ;
float zlev(zlev) ;
zlev:long_name = "Sea surface height" ;
zlev:units = "meters" ;
zlev:actual_range = "0, 0" ;
float lat(lat) ;
lat:long_name = "Latitude" ;
lat:units = "degrees_north" ;
lat:grids = "Uniform grid from -88 to 88 by 2" ;
float lon(lon) ;
lon:long_name = "Longitude" ;
lon:units = "degrees_east" ;
lon:grids = "Uniform grid from 0 to 358 by 2" ;
short sst(time, zlev, lat, lon) ;
sst:long_name = "Extended reconstructed sea surface temperature" ;
sst:units = "degrees C" ;
sst:_FillValue = -999s ;
sst:add_offset = 0.f ;
sst:scale_factor = 0.0099999998f ;
sst:valid_min = -300s ;
sst:valid_max = 4500s ;
short anom(time, zlev, lat, lon) ;
anom:long_name = "Extended reconstructed SST anomalies" ;
anom:units = "degrees C" ;
anom:_FillValue = -999s ;
anom:add_offset = 0.f ;
anom:scale_factor = 0.0099999998f ;
anom:valid_min = -1200s ;
anom:valid_max = 1200s ;
short err(time, zlev, lat, lon) ;
err:long_name = "Estimated error standard deviation of analyzed_ersst" ;
err:units = "degrees C" ;
err:_FillValue = -999s ;
err:add_offset = 0.f ;
err:scale_factor = 0.0099999998f ;
err:valid_min = 0s ;
err:valid_max = 1000s ;
// global attributes:
:title = "ERSST" ;
:history = "Version 3.0" ;
:description = "Smith, T.M., and R.W. Reynolds, 2003: Extended Reconstruction of Global Sea Surface
Temperatures Based on COADS Data (1854-1997). Journal of Climate, 16, 1495-1510.
A vailable at http://www.ncdc.noaa.gov/img/climate/research/sst/ersst.pdf
Climatology is based on 1971-2000 OI.v2 SST, Satellite data: Navy NOAA17 AVHRR" ;
:source = "NOAA/National Climatic Data Center" ;
:contact = "Dick Reynolds, email: [email protected] &
Chunying Liu, email: [email protected]" ;
:netcdf_Convention = "COARDS" ;
}
Thomas M. Smith (e-mail: [email protected])
National Climate Data Center
4115 Computer and Space Sciences Building
University of Maryland
College Park, MD 20742-2465 USA
Richard W. Reynolds (e-mail: [email protected])
National Climate Data Center
151 Patton Ave., Room 514,
Asheville, NC 28801
UPDATED: 12 September 2007
