Plant Hardiness Zones

This map of plant hardiness zones shows the average annual extreme minimum temperature (from 1976-2005) across the contiguous United States. Data via Bill Morris’ Open Plant Hardiness Zones project.

forked from mbostock's block: Plant Hardiness Zones

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</style>
<body>
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<script>

var width = 960,
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    .domain([-35, 0, 35])
    .range(["#4575b4", "#ffffbf", "#a50026"])
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    .domain([-40, 40])
    .range([0, 240]);

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    .tickSize(13)
    .tickFormat(d3.format("+.0f"));

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svg.selectAll("rect")
    .data(pair(x.ticks(10)))
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    .attr("height", 20)
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    .attr("width", function(d) { return x(d[1]) - x(d[0]); })
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svg.call(xAxis).append("text")
    .attr("class", "caption")
    .attr("y", -6)
    .text("Avg. annual extreme minimum temperature, °F");

d3.json("ophz.json", function(error, ophz) {
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      .features
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https://d3js.org/d3.v3.min.js

https://d3js.org/topojson.v1.min.js