Re-projecting using GDAL with Rasterio and Fiona#

The simplest method of re-projecting is GeoDataFrame.to_crs(). It uses pyproj as the engine and transforms the points within the geometries.

These examples demonstrate how to use Fiona or rasterio as the engine to re-project your data. Fiona and rasterio are powered by GDAL and with algorithms that consider the geometry instead of just the points the geometry contains. This is particularly useful for antimeridian cutting. However, this also means the transformation is not as fast.

Fiona example#

from functools import partial

import fiona
import geopandas
from fiona.transform import transform_geom
from packaging import version
from pyproj import CRS
from pyproj.enums import WktVersion
from shapely.geometry import mapping, shape


# set up Fiona transformer
def crs_to_fiona(proj_crs):
    proj_crs = CRS.from_user_input(proj_crs)
    if version.parse(fiona.__gdal_version__) < version.parse("3.0.0"):
        fio_crs = proj_crs.to_wkt(WktVersion.WKT1_GDAL)
    else:
        # GDAL 3+ can use WKT2
        fio_crs = proj_crs.to_wkt()
    return fio_crs

def base_transformer(geom, src_crs, dst_crs):
    return shape(
        transform_geom(
            src_crs=crs_to_fiona(src_crs),
            dst_crs=crs_to_fiona(dst_crs),
            geom=mapping(geom),
            antimeridian_cutting=True,
        )
    )

# load natural earth land data
world = geopandas.read_file("https://naciscdn.org/naturalearth/110m/physical/ne_110m_land.zip")

destination_crs = "EPSG:3395"
forward_transformer = partial(base_transformer, src_crs=world.crs, dst_crs=destination_crs)

# Reproject to Mercator (after dropping Antartica)
world = world.drop(7)
with fiona.Env(OGR_ENABLE_PARTIAL_REPROJECTION="YES"):
    mercator_world = world.set_geometry(world.geometry.apply(forward_transformer), crs=destination_crs)

Rasterio example#

This example requires rasterio 1.2+ and GDAL 3+.

import geopandas
import rasterio.warp
from shapely.geometry import shape

# load example data
world = geopandas.read_file("https://naciscdn.org/naturalearth/110m/physical/ne_110m_land.zip")
# Reproject to Mercator (after dropping Antartica)
world = world.drop(7)
destination_crs = "EPSG:3395"
geometry = rasterio.warp.transform_geom(
    src_crs=world.crs,
    dst_crs=destination_crs,
    geom=world.geometry.values,
)
mercator_world = world.set_geometry(
    [shape(geom) for geom in geometry],
    crs=destination_crs,
)