Plotting ERA5 Daily wind speed in Python/Folium - image not found

Question

I am trying to plot the latest wind speeds from https://developers.google.com/earth-engine/datasets/catalog/ECMWF_ERA5_DAILY . It is supposedly an "ImageCollection". When I run the code below, I get the traceback "EEException: Image.visualize: Parameter 'image' is required.". I've added an i_date just to be sure I search over a reasonable range of dates - to make sure there's data available.

May I know where I may have gotten it wrong / how I may work around this issue? Thank you very much!

import ee

# Trigger the authentication flow.
ee.Authenticate()

# Initialize the library.
ee.Initialize()


wind = ee.ImageCollection('ECMWF/ERA5/DAILY')
i_date = '2022-04-28'
f_date = '2022-07-01'
wind= ee.ImageCollection('ECMWF/ERA5/DAILY')

import folium


def add_ee_layer(self, ee_image_object, vis_params, name):
    """Adds a method for displaying Earth Engine image tiles to folium map."""
    map_id_dict = ee.Image(ee_image_object).getMapId(vis_params)
    folium.raster_layers.TileLayer(
        tiles=map_id_dict['tile_fetcher'].url_format,
        attr='Map Data &copy; <a href="https://earthengine.google.com/">Google Earth Engine</a>',
        name=name,
        overlay=True,
        control=True
    ).add_to(self)

# Add Earth Engine drawing method to folium.
folium.Map.add_ee_layer = add_ee_layer

wind_img=wind.select('u_component_of_wind_10m').filterDate(i_date,f_date).first()
# wind_img=wind_img.mean()

# Set visualization parameters for land surface temperature.
wind_vis_params = {
    'min': 0, 'max': 40,
    'palette': ['white', 'blue', 'green', 'yellow', 'orange', 'red']}

ee_tiles_names = ['Land Surface Temperature']

# Create a new map.
lat, lon = 45.77, 4.855
my_map = folium.Map(location=[lat, lon], zoom_start=5)

# Add layers to the map using a loop.
my_map.add_ee_layer(wind_img, wind_vis_params, 'Wind Speed')

my_map.add_child(folium.LayerControl())
folium.LayerControl(collapsed = False).add_to(my_map)

my_map.save("c:/data/weather.html")
import webbrowser
webbrowser.open("c:/data/weather.html")

score 0 · Answer 1 · answered Jul 02 '22 at 13:36

This is dumb of me. I just realised the data set ends in 2020. Here's the revised code:

# -*- coding: utf-8 -*-
"""
Created on Fri Jul  1 10:04:39 2022

@author: xxx
"""

import ee

# Trigger the authentication flow.
ee.Authenticate()

# Initialize the library.
ee.Initialize()


wind = ee.ImageCollection('NOAA/GFS0P25')
i_date = '2022-06-30'
f_date = '2022-07-01'
# wind= ee.ImageCollection('ECMWF/ERA5/DAILY')

import folium


def add_ee_layer(self, ee_image_object, vis_params, name):
    """Adds a method for displaying Earth Engine image tiles to folium map."""
    map_id_dict = ee.Image(ee_image_object).getMapId(vis_params)
    folium.raster_layers.TileLayer(
        tiles=map_id_dict['tile_fetcher'].url_format,
        attr='Map Data &copy; <a href="https://earthengine.google.com/">Google Earth Engine</a>',
        name=name,
        overlay=True,
        control=True
    ).add_to(self)

# Add Earth Engine drawing method to folium.
folium.Map.add_ee_layer = add_ee_layer

wind_img=wind.select('u_component_of_wind_10m_above_ground').filterDate(i_date,f_date).first()
# wind_img=wind_img.mean()

# Set visualization parameters for land surface temperature.
wind_vis_params = {
    'min': 0, 'max': 40,
    'palette': ['white', 'blue', 'green', 'yellow', 'orange', 'red']}

ee_tiles_names = ['Wind Speed']

# Create a new map.
lat, lon = 45.77, 4.855
my_map = folium.Map(location=[lat, lon], zoom_start=5)

# Add layers to the map using a loop.
my_map.add_ee_layer(wind_img, wind_vis_params, 'Wind Speed')

my_map.add_child(folium.LayerControl())
folium.LayerControl(collapsed = False).add_to(my_map)

my_map.save("c:/data/weather.html")
import webbrowser
webbrowser.open("c:/data/weather.html")

Plotting ERA5 Daily wind speed in Python/Folium - image not found

1 Answers1