Как я могу выбрать широту/долготу для набора данных NetCDF, если они заданы как координаты (а не размеры)? ⇐ Python

[Anonymous]

Я работаю с данными NetCDF. Размеры набора данных Xarray указаны как «x», «y», «time», а координаты — «lon» (y,x), «lat» (x,y) и «time».Я хочу найти значение переменной «температура» в определенную широту, долготу и время.

• Это можно ли использовать для этого sel? (Я знаю, как это сделать, если бы широта/долгота были размерами... но не при заданных координатах).
  ds.temp.sel(time='2018-01-01' , lat=-59.71, lon=89.9).values
• Кроме того, о чем мне говорят (x,y) в скобках (и почему x И y, если каждый из они относятся либо к широте, либо к долготе)?

Я видел предложения по повторной сетке данных, но не уверен, насколько это поможет. Также видел документацию по многомерным координатам и картографическим данным. Однако они не отвечают на вопрос (https://docs.xarray.dev/en/latest/examp ... oords.html)
ds.tas_ymonmean.sel(time=time, x=lat, y=lon).values #TypeError: invalid indexer array, does not have integer dtype: array(-8.229)

Вот результаты дампа NCO:
dimensions:
x = 1000 ;
y = 950 ;
time = UNLIMITED ; // (12 currently)
variables:
float lon(y, x) ;
lon:standard_name = "longitude" ;
lon:long_name = "longitude" ;
lon:units = "degrees_east" ;
lon:_CoordinateAxisType = "Lon" ;
float lat(y, x) ;
lat:standard_name = "latitude" ;
lat:long_name = "latitude" ;
lat:units = "degrees_north" ;
lat:_CoordinateAxisType = "Lat" ;
double height ;
height:standard_name = "height" ;
height:long_name = "height" ;
height:units = "m" ;
height:positive = "up" ;
height:axis = "Z" ;
double time(time) ;
time:standard_name = "time" ;
time:long_name = "time" ;
time:units = "days since 1949-12-01 00:00:00" ;
time:calendar = "360_day" ;
time:axis = "T" ;
float tas_ymonmean(time, y, x) ;
tas_ymonmean:_FillValue = 1.e+20f ;
tas_ymonmean:missing_value = 1.e+20f ;
tas_ymonmean:standard_name = "mean_temperature_index_per_time_period" ;
tas_ymonmean:long_name = "mean air temperature (seasonality)" ;
tas_ymonmean:units = "Degree Celsius" ;
tas_ymonmean:cell_methods = "time:mean" ;
tas_ymonmean:associated_files = "-" ;
tas_ymonmean:cell_measures = "area:areacella" ;
tas_ymonmean:history = "-" ;
tas_ymonmean:title = "Mean monthly temperature" ;
tas_ymonmean:coordinates = "lat lon height" ;
tas_ymonmean:variable = "tas_ymonmean" ;

// global attributes:
:CDI = "Climate Data Interface version 1.8.2 (http://mpimet.mpg.de/cdi)" ;
:experiment = "Historical run" ;
:experiment_id = "historical" ;
:realization = "1" ;
:driving_experiment = "MOHC-HadGEM2-ES,historical,r1i1p1" ;
:driving_model_id = "MOHC-HadGEM2-ES" ;
:driving_model_ensemble_member = "r1i1p1" ;
:driving_experiment_name = "historical" ;
:model_id = "KNMI-RACMO22E" ;
:rcm_version_id = "v2" ;
:CORDEX_domain = "EUR-11" ;
:product = "output" ;
:frequency = "day" ;
:knmi_global_comment = "HadGEM2-ES forced RACMO2 simulation with corrected latitudinal SST-remapping" ;
:knmi_model_comment = "RACMO22E: baseline physics from ECMWF CY31r1; modifications include HTESSEL CY33r1, patch K-diffusion CY32r3, moist Turbulent Kinetic Energy, satellite inferred Leaf Area Index" ;
:knmi_version_comment = "v2: replaces withdrawn results with RCMVersionID = v1 (this applies only to HadGEM2-ES forced RACMO2 simulations)" ;
:knmi_grib_path = "mos.knmi.nl:/climreg/CXEUR12/eSSTcorr-v496-fHadGEM2-r1i1p1+hist/GRIB_data" ;
:tracking_id = "82a803d5-e106-4f6a-8718-ded1370e8c96" ;
:CDO = "Climate Data Operators version 1.8.2 (http://mpimet.mpg.de/cdo)" ;
:creation_date = "2020-02-12T15:38:01ZCET+0100" ;
:Conventions = "CF-1.6" ;
:institution_url = "www.smhi.se" ;
:invar_platform_id = "-" ;
:invar_rcm_model_driver = "MOHC-HadGEM2-ES" ;
:invar_bc_method_id = "-" ;
:invar_bc_observation_id = "-" ;
:invar_bc_period = "-" ;
:time_coverage_start = "1971" ;
:time_coverage_end = "2000" ;
:domain = "EUR-11" ;
:geospatial_lat_min = "23.942343" ;
:geospatial_lat_max = "72.641624" ;
:geospatial_lat_resolution = "0.04268074 degree" ;
:geospatial_lon_min = "-35.034023" ;
:geospatial_lon_max = "73.937675" ;
:geospatial_lon_resolution = "0.009246826 degree" ;
:geospatial_bounds = "-" ;
:NCO = "netCDF Operators version 4.7.7 (Homepage = http://nco.sf.net, Code = http://github.com/nco/nco)" ;
:source = "The RCM data originate from EURO-CORDEX (Coordinated Downscaling Experiment - European Domain, EUR-11) https://euro-cordex.net/." ;
:institution = "SMHI" ;
:contact = "[email protected]" ;
:references = "-" ;
:project_id = "C3S_424_SMHI" ;
:acknowledgements = "This work was performed within Copernicus Climate Change Service - C3S_424_SMHI, https://climate.copernicus.eu/operation ... ter-sector, on behalf of ECMWF and EU." ;
:data_quality = "Testing of EURO-CORDEX data performed by ESGF nodes. Additional tests were performed when producing CII and ECVs in C3S_424_SMHI" ;
:keywords = "temperature, air" ;
:license = "Copernicus License V1.2" ;
:output_frequency = "30 year monthly average values" ;
:summary = "Calculated as the mean monthly values of daily mean temperature averaged over all Januaries, Februaries, etc that are part of a 30 year period." ;
:title = "Temperature derived climate impact indicator" ;
:comment = "The Climate Data Operators (CDO) software was used for the calculation of climate impact indicators (https://code.mpimet.mpg.de/projects/cdo ... ed/cdo.pdf, https://code.mpimet.mpg.de/projects/cdo ... do_eca.pdf)." ;
:history = "CDO commands (last cdo command first and separated with : ymonmean; monmean" ;
:invar_experiment_id = "historical" ;
:invar_realisation_id = "r1i1p1" ;
:invar_rcm_model_id = "KNMI-RACMO22E-v2" ;
:variable_name = "tas_ymonmean" ;


Подробнее здесь: https://stackoverflow.com/questions/792 ... se-are-giv