Some of the metadata for the daily/sub-daily seasonal forecasts are incorrect, for datasets from centres other than ECMWF: Seasonal forecast daily and subdaily data on single levels
I have downloaded a 4-9 variables from the ukmo, eccc, cmcc, and ncep as GRIB files, and some of the raster layers have the wrong GRIB_COMMENT, GRIB_ELEMENT and GRIB_UNIT.
For example, consider the following api request:
dataset = "seasonal-original-single-levels"
request = {
"originating_centre": "ukmo",
"system": "603",
"variable": [ "evaporation", "maximum_2m_temperature_in_the_last_24_hours", "minimum_2m_temperature_in_the_last_24_hours", "sub_surface_runoff", "surface_net_solar_radiation", "surface_runoff", "total_precipitation"
],
"year": ["1993"],
"month": ["02"],
"day": ["01"],
"leadtime_hour": [ "24", "48", "72", "96", "120", "144", "168", "192", "216", "240", "264", "288", "312", "336", "360", "384", "408", "432", "456", "480", "504", "528", "552", "576", "600", "624", "648", "672", "696", "720", "744", "768", "792", "816", "840", "864", "888", "912", "936", "960", "984", "1008", "1032", "1056", "1080", "1104", "1128", "1152", "1176", "1200", "1224", "1248", "1272", "1296", "1320", "1344", "1368", "1392", "1416", "1440", "1464", "1488", "1512", "1536", "1560", "1584", "1608", "1632", "1656", "1680", "1704", "1728", "1752", "1776", "1800", "1824", "1848", "1872", "1896", "1920", "1944", "1968", "1992", "2016", "2040", "2064", "2088", "2112", "2136", "2160", "2184", "2208", "2232", "2256", "2280", "2304", "2328", "2352", "2376", "2400", "2424", "2448", "2472", "2496", "2520", "2544", "2568", "2592", "2616", "2640", "2664", "2688", "2712", "2736", "2760", "2784", "2808", "2832", "2856", "2880", "2904", "2928", "2952", "2976", "3000", "3024", "3048", "3072", "3096", "3120", "3144", "3168", "3192", "3216", "3240", "3264", "3288", "3312", "3336", "3360", "3384", "3408", "3432", "3456", "3480", "3504", "3528", "3552", "3576", "3600", "3624", "3648", "3672", "3696", "3720", "3744", "3768", "3792", "3816", "3840", "3864", "3888", "3912", "3936", "3960", "3984", "4008", "4032", "4056", "4080", "4104", "4128", "4152", "4176", "4200", "4224", "4248", "4272", "4296", "4320", "4344", "4368", "4392", "4416", "4440", "4464", "4488", "4512", "4536", "4560", "4584", "4608", "4632", "4656", "4680", "4704", "4728", "4752", "4776", "4800", "4824", "4848", "4872", "4896", "4920", "4944", "4968", "4992", "5016", "5040", "5064", "5088", "5112", "5136", "5160"], "area": [61, -136, 48, -114]
"data_format": "grib"
}
The first 7 layers have the following metadata:
[31] "Band 1 Block=23x1 Type=Float64, ColorInterp=Undefined"
[32] " Description = 0[-] SFC (Ground or water surface)"
[33] " Metadata:"
[34] " GRIB_COMMENT=undefined [-]"
[35] " GRIB_ELEMENT=var182 of table 128 of center 74"
[36] " GRIB_FORECAST_SECONDS=86400"
[37] " GRIB_REF_TIME=728524800"
[38] " GRIB_SHORT_NAME=0-SFC"
[39] " GRIB_UNIT=[-]"
[40] " GRIB_VALID_TIME=728611200"
[41] "Band 2 Block=23x1 Type=Float64, ColorInterp=Undefined"
[42] " Description = 0[-] SFC (Ground or water surface)"
[43] " Metadata:"
[44] " GRIB_COMMENT=Specific humidity [kg/kg]"
[45] " GRIB_ELEMENT=SPFH"
[46] " GRIB_FORECAST_SECONDS=86400"
[47] " GRIB_REF_TIME=728524800"
[48] " GRIB_SHORT_NAME=0-SFC"
[49] " GRIB_UNIT=[kg/kg]"
[50] " GRIB_VALID_TIME=728611200"
[51] "Band 3 Block=23x1 Type=Float64, ColorInterp=Undefined"
[52] " Description = 0[-] SFC (Ground or water surface)"
[53] " Metadata:"
[54] " GRIB_COMMENT=Relative humidity [%]"
[55] " GRIB_ELEMENT=RH"
[56] " GRIB_FORECAST_SECONDS=86400"
[57] " GRIB_REF_TIME=728524800"
[58] " GRIB_SHORT_NAME=0-SFC"
[59] " GRIB_UNIT=[%]"
[60] " GRIB_VALID_TIME=728611200"
[61] "Band 4 Block=23x1 Type=Float64, ColorInterp=Undefined"
[62] " Description = 0[-] SFC (Ground or water surface)"
[63] " NoData Value=9999"
[64] " Metadata:"
[65] " GRIB_COMMENT=Standard deviation of height [m]"
[66] " GRIB_ELEMENT=HSTDV"
[67] " GRIB_FORECAST_SECONDS=86400"
[68] " GRIB_REF_TIME=728524800"
[69] " GRIB_SHORT_NAME=0-SFC"
[70] " GRIB_UNIT=[m]"
[71] " GRIB_VALID_TIME=728611200"
[72] "Band 5 Block=23x1 Type=Float64, ColorInterp=Undefined"
[73] " Description = 0[-] SFC (Ground or water surface)"
[74] " Metadata:"
[75] " GRIB_COMMENT=undefined [-]"
[76] " GRIB_ELEMENT=var176 of table 128 of center 74"
[77] " GRIB_FORECAST_SECONDS=86400"
[78] " GRIB_REF_TIME=728524800"
[79] " GRIB_SHORT_NAME=0-SFC"
[80] " GRIB_UNIT=[-]"
[81] " GRIB_VALID_TIME=728611200"
[82] "Band 6 Block=23x1 Type=Float64, ColorInterp=Undefined"
[83] " Description = 0[-] SFC (Ground or water surface)"
[84] " NoData Value=9999"
[85] " Metadata:"
[86] " GRIB_COMMENT=Geometric height [m]"
[87] " GRIB_ELEMENT=DIST"
[88] " GRIB_FORECAST_SECONDS=86400"
[89] " GRIB_REF_TIME=728524800"
[90] " GRIB_SHORT_NAME=0-SFC"
[91] " GRIB_UNIT=[m]"
[92] " GRIB_VALID_TIME=728611200"
[93] "Band 7 Block=23x1 Type=Float64, ColorInterp=Undefined"
[94] " Description = 0[-] SFC (Ground or water surface)"
[95] " Metadata:"
[96] " GRIB_COMMENT=undefined [-]"
[97] " GRIB_ELEMENT=var228 of table 128 of center 74"
[98] " GRIB_FORECAST_SECONDS=86400"
[99] " GRIB_REF_TIME=728524800"
[100] " GRIB_SHORT_NAME=0-SFC"
[101] " GRIB_UNIT=[-]"
[102] " GRIB_VALID_TIME=728611200"
So:
Layer 1 is correct-ish (GRIB_ELEMENT=var182 of table 128 of center 74" is evaporation). Would be nice if the GRIB_COMMENT was defined but that’s fine.
Layers 2 and 3 are labelled incorrectly as Specific humidity [kg/kg] and Relative humidity [%] - they should be “maximum_2m_temperature_in_the_last_24_hours” and “minimum_2m_temperature_in_the_last_24_hours”. When I plot the layers they are clearly temperatures in K(values from 240 to 280).
Layer 4 is incorrectly labelled as GRIB_COMMENT=Standard deviation of height [m], should be sub-surface runoff. The actual values in the raster seem like reasonable values for sub-surface runoff, but I can’t be sure.
Layer 5 is correct: I asked for surface_net_solar_radiation, and I got GRIB_ELEMENT=var176 of table 128 of center 74.
Layer 6 is incorrect: I asked for surface_runoff, and it is labelled as GRIB_COMMENT=Geometric height [m]. Again, the values seem reasonable for surface_runoff (and are most definitely not geometric height).
Layer 7 is correct: I asked for total_precipitation, and I got GRIB_ELEMENT=var228 of table 128 of center 74.
I also confirmed that ECCC, NCEP, meteo-france, and CMCC have similar errors.