SNAP documentation
METO data
Om has said we should drop the hybrid_ht variables for now.
The METO data is all in their pp format and can be found below /group_workspaces/jasmin/snap/meto/phase1/NH_SSW. This directory contains directories named after the start dates and each directory contains files of the form prodf_rs_sfc_ap<L>_<MM><date1_<date2>_<NN>.pp, where: <L> is equal to a, c, d or e (f and i are not required for SNAP; <MM> is a two digit number which doesn't change with directory; <date1> and <date2> are of the form YYYYMMDD; and <NN> runs from 001 to 022 for each directory and is the ensemble. For each ensemble and each <L> there should be two files: one where <date1 and <date2> are the same, and this is the first 15 days; and one where <date1 and <date2> are different and this is the next 15 days. The two sets of 15 days and the files where <L is equal to a, c, d and e need putting together.
Putting all the variables into one file
All these variables are put into file with the script /home/users/stringer/snap/bin/conformMeto.scr, which requires two arguments: the directory containing the data and the value of <NN>. The script then carries out the following
- For each pp file
- convert to netCDF using the /home/users/stringer/snap/bin/pp2nc.scr script, which uses Jeff Cole's convsh.
- Renaming the latitude and longitude dimensions, so we don't get them mixed up
- Rename other variables for each file because there are further variable name conflicts, e.g. u is used for both U at 10m and U across all pressure levels.
- Put the first 15 day files into one file
- Put the second 15 day files into another file
- Extract variable precip from each file into precip1.nc and precip2.nc, it's the only variable to depend on t_1, rather than t.
- Put the first and second 15 days together for both the main files and the precip files.
- For the combined precip file, make t_1 a fixed dimension, and then put it into the main combined file
- Lots of renaming of variables and long names, according to the table below.
After using Jeff Cole's convsh software the old variables are given in the table below.
| Old variable name | Old variable long name | Dimensions | New variable name | New variable long name |
|---|---|---|---|---|
| Dimensions | ||||
| hybrid_ht (apd it's 63, ape it's 3) | Hybrid height | hybrid_ht | hybrid_ht (when 63) & hybrid_ht_low (when 3) | hybrid height |
| hybrid_ht_1 (in ape it's 63) | Hybrid height | hybrid_ht_1 | hybrid_ht | hybrid height |
| ht (apa, also a ht in apc file) | ht | Removed | ||
| latitude/latitude_1 (I don't think you can ever be sure with which was is which without checking) | latitude/latitude_1 | latitude/ latitude_2 | latitude | latitude |
| longitude/longitude_1 (I don't think you can ever be sure with which was is which without checking) | longitude/longitude_1 | longitude/ longitude_2 | longitude | longitude |
| theta (apd) | Potential temperature | theta | theta | potential temperature |
| p (apc file, also a p in ape file) | Pressure | p | pres | pressure |
| surface | Surface | surface | removed | |
| t | t | t | t | time |
| t_1 (only apa) | t | t_1 | day | time |
| Variables | ||||
| field424 (apd) | EASTWARD FORCE FROM SPECTRAL GW | (longitude, latitude_1, hybrid_t, t) | GWESP | Eastward force from spectral gw scheme |
| field425 (apd) | NORTHWARD FORCE FROM SPECTRAL GW | (longitude, latitude_1, hybrid_t, t) | GWNSP | Northward force from spectral gw scheme |
| ht (apc) | Height (standard name is geopotential_height) | (longitude_1, latitude_1, p, t) | ZH | Geopotential height |
| p (ape, also a p in apc) | Pressure | (longitude_1, latitude_1, hybrid_ht_1, t) | PRES | Pressure |
| p_1 (ape) | Pressure | (longitude_1, latitude_1, hybrid_ht, t) | PRES_2 | Pressure at low levels |
| precip (apa) | Total precipitation rate | (longitude_1, latitude_1, surface, t_1) | TPR | Total precipitation rate (differs to TP) |
| pv (apd) | Ertel potential vorticity (Q) | (longitude_1, latitude_1, theta, t) | PV | Potential vorticity |
| u (apa) | Westerly component of wind u | (longitude, latitude, ht (removed), t) | U10 | 10 metre U wind component |
| u (apc) | Westerly component of wind u | (longitude, latitude, p, t) | U | U velocity |
| unspecified (apd) | Standard name is tendency_of_eastward_wind_ due_to_gravity_wave_drag | (longitude_1, latitude, hybrid_ht, t) | GWUT | Tendency of eastward wind due to gravity wave drag |
| unspecified_1 (apd) | Standard name is tendency_of_northward_wind_ due_to_gravity_wave_drag | (longitude_1, latitude, hybrid_ht, t) | GWVT | Tendency of northward wind due to gravity wave drag |
| v (apa) | Southerly component of wind v | (longitude, latitude, ht (removed), t) | V10 | 10 metre V wind component |
| v (apc) | Southerly component of wind u | (longitude, latitude, p, t) | V | V velocity |
| temp (apa) | Temperature T | (longitude_1, latitude_1, ht (removed), t) | T1_5 | 1.5 metre Temperature |
| temp (apc) | Temperature T | (longitude_1, latitude_1, p, t) | T | Temperature |
| temp (ape) | Temperature T | (longitude_1, latitude_1, hybrid_ht, t) | T_2 | Temperature at lower levels |