Python - How to get variable from netcdf file on a specific location and at different level

Question

I am learning on how to plot various variables from WRF output netcdf file. My requirement is to extract variables for a certain lat/lon (8.4875° N, 76.9525° E) in order to plot SkewT profiles using the matplotlib package.

I found a similar question on this SO page netcdf4 extract for subset of lat lon . However, its location is a set of boundaries.

Answer 1

Check out xray . You'll have to do some work to make the SkewT chart but accessing and summarizing the netCDF Dataset and variables will be pretty easy. Just a few examples below.

import xray

ds = xray.open_dataset('your_wrf_file.nc')

ds_point = ds.sel(lon=76.9525, lat=8.4875)

ds_point['Temperature'].plot()  # plot profile at point assuming Temperature had dimensions of (level, lat, lon)

df = ds_point.to_dataframe()  # export dataset to Pandas.DataFrame

temp_array = ds_point['Temperature'].values  # access the underlying numpy array of the "Temperature" variable

Answer 2

我通常要做的是在使用ncl，python，R等进行绘图之前，使用CDO从命令行中提取最接近网格点的列：

cdo remapnn,lon=76.9525/lat=8.4875 wrf_file.nc pnt_file.nc