简介
美国干旱监测 "是每周四发布的地图，显示美国部分地区的干旱情况。 该地图采用五种分级：异常干旱（D0），显示可能进入或即将摆脱干旱的地区；四级干旱：中度（D1）、严重（D2）、极度（D3）和异常（D4）。 干旱监测仪自 1999 年推出以来，一直由内布拉斯加大学林肯分校的国家干旱缓解中心 (NDMC)、美国国家海洋与大气管理局 (NOAA) 和美国农业部 (USDA) 联合制作。 内布拉斯加大学林肯分校的 NDMC 负责管理干旱监测网站和相关数据，并向 NOAA、USDA 和其他机构提供地图和数据。 该网站可在 droughtmonitor.unl.edu 免费查阅。
数据集说明
空间信息
Dataset Availability
2000-01-04T00:00:00 -
Dataset Provider
National Drought Mitigation Center
Contact
Contact information not available.
Collection Snippet
Copied
ee.ImageCollection("projects/sat-io/open-datasets/us-drought-monitor")
变量
Resolution
250 meters
Bands Table
Name Description Min Max
b1
Drought classes
0 4
代码
var usdm = ee.ImageCollection(
"projects/sat-io/open-datasets/us-drought-monitor"
);
/
Category Description
DO Abnormally Dry
D1 Moderate Drought
D2 Severe Drought
D3 Extreme Drought
D4 Exceptional Drought /
var usdm = ee.Image(usdm.toList(usdm.size()).get(-1));
// Define a dictionary which will be used to make legend and visualize image on map
var dict = {
names: [
"DO Abnormally Dry", //1
"D1 Moderate Drought", //2
"D2 Severe Drought", //3
"D3 Extreme Drought", //4
"D4 Exceptional Drought", //5
],
colors: ["FFFF00", "FCD37F", "FFAA00", "E60000", "730000"],
};
// Create a panel to hold the legend widget
var legend = ui.Panel({
style: {
position: "bottom-left",
padding: "8px 15px",
},
});
// Function to generate the legend
function addCategoricalLegend(panel, dict, title) {
// Create and add the legend title.
var legendTitle = ui.Label({
value: title,
style: {
fontWeight: "bold",
fontSize: "18px",
margin: "0 0 4px 0",
padding: "0",
},
});
panel.add(legendTitle);
var loading = ui.Label("Loading legend...", { margin: "2px 0 4px 0" });
panel.add(loading);
// Creates and styles 1 row of the legend.
var makeRow = function (color, name) {
// Create the label that is actually the colored box.
var colorBox = ui.Label({
style: {
backgroundColor: color,
// Use padding to give the box height and width.
padding: "8px",
margin: "0 0 4px 0",
},
});
// Create the label filled with the description text.
var description = ui.Label({
value: name,
style: { margin: "0 0 4px 6px" },
});
return ui.Panel({
widgets: [colorBox, description],
layout: ui.Panel.Layout.Flow("horizontal"),
});
};
// Get the list of palette colors and class names from the image.
var palette = dict["colors"];
var names = dict["names"];
loading.style().set("shown", false);
for (var i = 0; i < names.length; i++) {
panel.add(makeRow(palette[i], names[i]));
}
Map.add(panel);
}
/
// Display map and legend /////////////////////////////////////////////////////////////////////////////// /
// Add the legend to the map
addCategoricalLegend(legend, dict, "US Drought Monitor");
// Add USDM Image image to the map
Map.addLayer(
usdm,
{ min: 0, max: 4, palette: dict["colors"] },
usdm.get("system:index").getInfo()
);
结果
代码2
var adminBounds = ee.FeatureCollection('FAO/GAUL_SIMPLIFIED_500m/2015/level1');
var usdm = ee.Image(
ee
.ImageCollection("projects/sat-io/open-datasets/us-drought-monitor")
.sort("system:time_start", false)
.first()
);
var lon = -98.19;
var lat = 40;
Map.setCenter(lon, lat, 5);
var gray = 200;
var background = ee.Image.rgb(gray, gray, gray).visualize({ min: 0, max: 255 });
// Degrees in EPSG:3857.
var delta = 10;
// Width and height of the thumbnail image.
var pixels = 256;
var image = usdm.visualize({
min: 0,
max: 4,
palette: ["FFFF00", "FCD37F", "FFAA00", "E60000", "730000"],
});
Map.addLayer(
image,
{},
"United States Drought Monitor (USDM; Drought Class)",
false
);
var areaOfInterest = ee.Geometry.Rectangle(
[lon - delta, lat - delta, lon + delta, lat + delta],
null,
false
);
var imageParams = {
dimensions: [pixels, pixels],
region: areaOfInterest,
crs: "EPSG:3857",
format: "png",
};
var land = adminBounds.style('FF000000', 0, 'CIRCLE', 0, '888888');
var stateLines = adminBounds.style('black', 1, 'CIRCLE', 1, 'FF000000');
var imageWithBackground =
ee.ImageCollection([background, land, image, stateLines]).mosaic();
Map.addLayer(imageWithBackground, {}, "United States Drought Monitor");
print(ui.Thumbnail({ image: imageWithBackground, params: imageParams }));
引用
Sims, K., Reith, A., Bright, E., Kaufman, J., Pyle, J., Epting, J., Gonzales, J., Adams, D., Powell, E., Urban, M., & Rose, A. (2023). LandScan Global 2022 [Data set]. Oak Ridge National Laboratory. ORNL LandScan Viewer - Oak Ridge National Laboratory
许可
National Drought Mitigation Center; U.S. Department of Agriculture; National Oceanic and Atmospheric Administration (2023). United States Drought Monitor. University of Nebraska-Lincoln. Current Map | U.S. Drought Monitor. Accessed 2023-09-17
网址推荐
知识星球
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机器学习
干旱监测平台
慧天干旱监测与预警-首页https://www.htdrought.com/
