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I have been trying to convert one of Sentinel-5P (Sentinel-5P Data) dataset (viz. 'methane_mixing_ratio_precision') to GeoTIFF file. The plot of one of its dataset viz. 'methane_mixing_ratio_precision' using the below code is methane_mixing_ratio_precision:

import xarray
import matplotlib.pyplot as plt
netcdf_fname = r'C:\Users\User\Desktop\NC Files\CH4_1.nc'
xds = xarray.open_dataset(netcdf_fname, group='PRODUCT')
plt.figure(figsize=(14,8))
ax = plt.axes()
xds.methane_mixing_ratio_precision[0].plot.pcolormesh(ax=ax, x='longitude', y='latitude',add_colorbar=True, cmap='jet');

Till now I have successfully created a point shapefile (Point Shapefile) of the above mentioned dataset. Now I want to convert this point shapefile to polygon shapefile which then I can rasterize to get GeoTIFF file as shown in methane_mixing_ratio_precision.

Using @gene suggestion, I was successfully able to create a buffer (7Km x 7Km) around each point geometry using geopandas:

import geopandas as gpd
points = gpd.read_file(r'C:\Users\User\Desktop\NC Files\methane_mixing_ratio_precision_points.shp')
points.geometry= points.geometry.apply(lambda x: x.buffer(0.063, cap_style = 3))
points.to_file(r'C:\Users\User\Desktop\NC Files\methane_mixing_ratio_precision_points_buffer.shp')

What I basically want is to create a grid (inclined in nature) of (5.5 Km * 3.5 Km) around each point geometry and that grid should like Section of Methane Plot.

1 Answer 1

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When you buffer the points GeoDataFrame with buffer = points.buffer the columns of the original points are not preserved

points.head(3)
   Param       Lat        Lon                  geometry
0  3.964342  5.185295  71.578270  POINT (71.57827 5.18530)
1  3.910507  5.206082  71.648300  POINT (71.64830 5.20608)
2  3.990862  5.226586  71.717873  POINT (71.71787 5.22659)
buffer = points.buffer(0.126, cap_style = 3)
buffer.head(3)
0    POLYGON ((71.70427 5.31130, 71.70427 5.05930, ...
1    POLYGON ((71.77430 5.33208, 71.77430 5.08008, ...
2    POLYGON ((71.84387 5.35259, 71.84387 5.10059, ...

A solution

# copy the original GeoDataFrame to preserve the columns
buffer = points.copy()
buffer.geometry= buffer.geometry.apply(lambda x: x.buffer(0.126, cap_style = 3))
buffer.head(3)
  Param       Lat        Lon                                           geometry
0  3.964342  5.185295  71.578270  POLYGON ((71.70427 5.31130, 71.70427 5.05930, ...
1  3.910507  5.206082  71.648300  POLYGON ((71.77430 5.33208, 71.77430   5.08008, ...
2  3.990862  5.226586  71.717873  POLYGON ((71.84387 5.35259, 71.84387 5.10059, ...
buffer.plot(column='Param')

enter image description here

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  • Hi @gene. "from shapely.geometry import buffer" is throwing following error: "ImportError: cannot import name 'buffer' from 'shapely.geometry' (C:\Users\User\Anaconda3\envs\Sentinel-5P\lib\site-packages\shapely\geometry_init_.py)".
    – RRSC NGP
    May 25, 2022 at 4:33
  • Sorry eliminate thé line
    – gene
    May 26, 2022 at 8:18

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