Contents

Geospatial Transforms

Geospatial Transforms

Instructors: Tyler Sutterley, Hannah Besso and Scott Henderson, some material adapted from David Shean

Learning Objectives

  • Review fundamental concepts of geospatial coordinate reference systems (CRS)

  • Learn how to access CRS metadata

  • Learn basic coordinate transformations relevant to ICESat-2

Introduction

ICESat-2 elevations are spatial point data. Spatial data contains information about where on the surface of the Earth a certain feature is located, and there are many different ways to define this location. While this seems straightforward, two main characteristics of the Earth make defining locations difficult:

  1. Earth is 3-dimensional (working with spatial data would be a lot easier if the world were flat)!

  2. Paper maps and computer screens are flat, which causes issues when we try to use them to display rounded shapes (like the Earth’s surface). Making things even more difficult, the irregular shape of the Earth means there is no one perfect model of its surface on which we could place our spatial data points! Instead, we’re left with many models of the Earth’s surface that are optimized for different locations and purposes.

import geopandas as gpd
import hvplot.xarray
from IPython.display import Image
import matplotlib.patches
import matplotlib.pyplot as plt
from mpl_toolkits import mplot3d
import netCDF4
import netrc
import numpy as np
import os
import osgeo.gdal, osgeo.osr
import pyproj
import rasterio
import rasterio.features
import rasterio.warp
import rioxarray
import re
import warnings
import xarray as xr
# import routines for this notebook
import utilities
# turn off warnings
warnings.filterwarnings('ignore')