21:null 22:["$","title",null,{"children":"Watch the Smoke from Australia’s Bushfires Swirl Across the Globe | Jeremy Ashkenas | Observable"}] 27:T506,fragmentShader = { const shader = gl.createShader(gl.FRAGMENT_SHADER); gl.shaderSource(shader, ` precision highp float; uniform sampler2D u_image; uniform vec2 u_translate; uniform float u_scale; uniform vec2 u_rotate; const float c_pi = 3.14159265358979323846264; const float c_halfPi = c_pi * 0.5; const float c_twoPi = c_pi * 2.0; float cosphi0 = cos(u_rotate.y); float sinphi0 = sin(u_rotate.y); void main(void) { float x = (gl_FragCoord.x - u_translate.x) / u_scale; float y = (u_translate.y - gl_FragCoord.y) / u_scale; // inverse orthographic projection float rho = sqrt(x * x + y * y); if (rho > 1.0) return; float c = asin(rho); float sinc = sin(c); float cosc = cos(c); float lambda = atan(x * sinc, rho * cosc); float phi = asin(y * sinc / rho); // inverse rotation float cosphi = cos(phi); float x1 = cos(lambda) * cosphi; float y1 = sin(lambda) * cosphi; float z1 = sin(phi); lambda = atan(y1, x1 * cosphi0 + z1 * sinphi0) + u_rotate.x; phi = asin(z1 * cosphi0 - x1 * sinphi0); gl_FragColor = texture2D(u_image, vec2((lambda + c_pi) / c_twoPi, (phi + c_halfPi) / c_pi)); } `); gl.compileShader(shader); if (!gl.getShaderParameter(shader, gl.COMPILE_STATUS)) throw new Error(gl.getShaderInfoLog(shader)); return shader; }28:[] 25:{"id":"828edc0302b51c4c","slug":"watch-the-smoke-from-australias-bushfires-swirl-across-the","title":"Watch the Smoke from Australia’s Bushfires Swirl Across the Globe","thumbnail":"166ab8d51d305278b52e56c130351e875aa0dfeafc46111423cbf16b09714328","access_level":"public","create_time":"$D2020-01-24T21:15:20.207Z","update_time":"$D2020-04-05T02:22:27.283Z","view_time":null,"first_public_time":"$D2020-01-28T23:11:22.270Z","has_unpublished_edits":null,"fork":{"id":"49a4523c38d72a86","slug":"earths-changing-seasons-blue-marble","title":"Earth’s Changing Seasons (Blue Marble)","owner":{"id":"172cc08ef8a18a4b","login":"jashkenas","name":"Jeremy Ashkenas"}},"stars":66,"starred":false,"owner":{"type":"team","id":"172cc08ef8a18a4b","login":"jashkenas","name":"Jeremy Ashkenas","avatar_url":"https://avatars-next.observableusercontent.com/fa1903f8171d4621ef49de28e0ff1fb965960ec87df175d8b543c4b09508b45b","tier":"starter_2024","bio":"Used to work on @observablehq — still think it rocks.\n🏍 🌎 👶"},"version":791,"publish_version":791,"role":null,"authored":false,"authors":[{"type":"individual","id":"783616ba9fb55f5d","login":"jashkenas","name":"Jeremy Ashkenas","avatar_url":"https://avatars-next.observableusercontent.com/fa1903f8171d4621ef49de28e0ff1fb965960ec87df175d8b543c4b09508b45b","tier":null,"bio":"Used to work on @observablehq — still think it rocks.\n🏍 🌎 👶"}],"members":[{"type":"individual","id":"783616ba9fb55f5d","login":"jashkenas","name":"Jeremy Ashkenas","avatar_url":"https://avatars-next.observableusercontent.com/fa1903f8171d4621ef49de28e0ff1fb965960ec87df175d8b543c4b09508b45b","tier":null,"role":"editor"}],"comments":[],"custom_thumbnail":true,"trashed":false,"lapsed":null,"subscribed":null,"forks":19,"collection":null,"type":"notebook","body":{"titling":"auto","title":"Watch the Smoke from Australia’s Bushfires Swirl Across the Globe","cells":[{"id":0,"value":"md`# Watch the Smoke from Australia’s Bushfires Swirl Across the Globe\n\nLast week, NASA published a mesmerizing video of several different types of particulates whirling across the atmosphere. The Terra/Aqua satellites captured the smoke from Australia’s bushfires crossing the South Pacific, smog emissions in Europe, hurricanes lifting sea salt into the atmosphere, and dust blowing off the Sahara Desert.\n\n*Source: [NASA Global Modeling and Assimilation Office](https://gmao.gsfc.nasa.gov/research/science_snapshots/2020/Australia_fires_smoke.php)*`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":461,"value":"viewof spin = checkbox({ options: [\"Spin the world\"], value: \"Spin the world\" })","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":680,"value":"viewof aus = button(\"Jump to Australia\")","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":375,"value":"viewof restart = button(\"Reset to Nov. 1\")","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":420,"value":"displayTime = html`

${formatTime(time)}

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${[\n aerosolLegend(\"Carbon (Fires)\", \"#400703\", \"#d75826\", \"#fbedd8\"),\n aerosolLegend(\n \"Nitrates (Exhaust, industry)\",\n \"#69112a\",\n \"#c36faf\",\n \"#f5f3f8\"\n ),\n aerosolLegend(\n \"Sulfates (Diesel, volcanoes)\",\n \"#1d4921\",\n \"#9acc8f\",\n \"#f4faf3\"\n ),\n aerosolLegend(\"Dust (Deserts)\", \"#6b2e12\", \"#f1aa4f\", \"#feffe3\"),\n aerosolLegend(\"Salt spray (The sea)\", \"#1d4582\", \"#98cec0\", \"#f5faed\", true)\n]}

`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"$undefined","database":"$undefined"},{"id":667,"value":"md`

\n\n## Appendix\n\n*The implementation of this notebook lies below. It is not yet organized or commented.*\n\n---\n\n

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