13 zonal statistics by group

Uncomment the following line to install geemap if needed.

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# !pip install geemap

# !pip install geemap

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import ee
import geemap
import os

import ee import geemap import os

Analyzing National Land Cover Database (NLCD)¶

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Map = geemap.Map()
Map

Map = geemap.Map() Map

Add NLCD data¶

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dataset = ee.Image("USGS/NLCD_RELEASES/2019_REL/NLCD/2019")
landcover = ee.Image(dataset.select("landcover"))
Map.addLayer(landcover, {}, "NLCD 2016")

states = ee.FeatureCollection("TIGER/2018/States")
Map.addLayer(states, {}, "US States")

dataset = ee.Image("USGS/NLCD_RELEASES/2019_REL/NLCD/2019") landcover = ee.Image(dataset.select("landcover")) Map.addLayer(landcover, {}, "NLCD 2016") states = ee.FeatureCollection("TIGER/2018/States") Map.addLayer(states, {}, "US States")

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Map.add_legend(builtin_legend="NLCD")

Map.add_legend(builtin_legend="NLCD")

Calculate land cover compostion of each US state¶

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out_dir = os.path.join(os.path.expanduser("~"), "Downloads")
nlcd_stats = os.path.join(out_dir, "nlcd_stats.csv")

if not os.path.exists(out_dir):
    os.makedirs(out_dir)

# statistics_type can be either 'SUM' or 'PERCENTAGE'
# denominator can be used to convert square meters to other areal units, such as square kilometers
geemap.zonal_stats_by_group(
    landcover,
    states,
    nlcd_stats,
    stat_type="SUM",
    denominator=1000000,
    decimal_places=2,
)

out_dir = os.path.join(os.path.expanduser("~"), "Downloads") nlcd_stats = os.path.join(out_dir, "nlcd_stats.csv") if not os.path.exists(out_dir): os.makedirs(out_dir) # statistics_type can be either 'SUM' or 'PERCENTAGE' # denominator can be used to convert square meters to other areal units, such as square kilometers geemap.zonal_stats_by_group( landcover, states, nlcd_stats, stat_type="SUM", denominator=1000000, decimal_places=2, )

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geemap.create_download_link(nlcd_stats)

geemap.create_download_link(nlcd_stats)

Analyzing Global Land Cover¶

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Map = geemap.Map()
Map

Map = geemap.Map() Map

Add MODIS global land cover data¶

MODIS MCD12Q1.006 Land Cover Type Yearly Global 500m

https://developers.google.com/earth-engine/datasets/catalog/MODIS_006_MCD12Q1

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landcover = ee.Image("MODIS/006/MCD12Q1/2013_01_01").select("LC_Type1")

vis = {
    "min": 1.0,
    "max": 17.0,
    "palette": [
        "05450a",
        "086a10",
        "54a708",
        "78d203",
        "009900",
        "c6b044",
        "dcd159",
        "dade48",
        "fbff13",
        "b6ff05",
        "27ff87",
        "c24f44",
        "a5a5a5",
        "ff6d4c",
        "69fff8",
        "f9ffa4",
        "1c0dff",
    ],
}

Map.setCenter(6.746, 46.529, 2)
Map.addLayer(landcover, vis, "MODIS Land Cover")

landcover = ee.Image("MODIS/006/MCD12Q1/2013_01_01").select("LC_Type1") vis = { "min": 1.0, "max": 17.0, "palette": [ "05450a", "086a10", "54a708", "78d203", "009900", "c6b044", "dcd159", "dade48", "fbff13", "b6ff05", "27ff87", "c24f44", "a5a5a5", "ff6d4c", "69fff8", "f9ffa4", "1c0dff", ], } Map.setCenter(6.746, 46.529, 2) Map.addLayer(landcover, vis, "MODIS Land Cover")

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Map.add_legend(builtin_legend="MODIS/006/MCD12Q1")

Map.add_legend(builtin_legend="MODIS/006/MCD12Q1")

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countries_shp = "../data/countries.shp"
countries = geemap.shp_to_ee(countries_shp)
Map.addLayer(countries, {}, "Countries")

countries_shp = "../data/countries.shp" countries = geemap.shp_to_ee(countries_shp) Map.addLayer(countries, {}, "Countries")

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out_dir = os.path.join(os.path.expanduser("~"), "Downloads")
global_stats = os.path.join(out_dir, "global_stats.csv")

# statistics_type can be either 'SUM' or 'PERCENTAGE'
# denominator can be used to convert square meters to other areal units, such as square kilimeters
geemap.zonal_stats_by_group(
    landcover,
    countries,
    global_stats,
    stat_type="PERCENTAGE",
    denominator=1000000,
    decimal_places=2,
)

out_dir = os.path.join(os.path.expanduser("~"), "Downloads") global_stats = os.path.join(out_dir, "global_stats.csv") # statistics_type can be either 'SUM' or 'PERCENTAGE' # denominator can be used to convert square meters to other areal units, such as square kilimeters geemap.zonal_stats_by_group( landcover, countries, global_stats, stat_type="PERCENTAGE", denominator=1000000, decimal_places=2, )

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geemap.create_download_link(global_stats)

geemap.create_download_link(global_stats)