The Daily Picture, Not the Ten-Metre One
Scrub daily NASA Worldview imagery over a box. Global, once a day, many sensors — the other timeline from the Sentinel-2 change tool.
A Sentinel-2 scene tells you what a few kilometres looked like at ten metres, every five days if the sky cooperated. A Worldview tile tells you what a whole coast looked like this morning, at the scale a daily polar orbiter can support. Those are different questions. This is the second one.
Try the browser preview — no install, no account. Scrub a few weeks of MODIS and VIIRS, recent HLS Landsat 30 m, or the nine WELD annual mosaics GIBS actually serves. Your browser reads NASA's public GIBS tiles itself. NASA sees which tiles you asked for. My server sees nothing, because there is not one.
Two timelines, on purpose
Sentinel-2 Timeline is the change-point tool: one grid, chromaticity, a threshold that was measured. It is the right instrument when the question is "when did this field or this pad change." It is the wrong instrument when the question is "what did the whole gulf look like on Tuesday," or when you need a layer that Sentinel-2 does not fly — night lights, a 7-2-1 burn scar, a true-colour morning pass over a storm.
Worldview Timeline keeps the daily stack. The desktop tool adds more layers and can export a film. This preview is a scrubber so you can see whether the ground moved at the scale a daily pass actually shows, before you spend the bandwidth on ten-metre dates.
There is no change-point fit here. A 250 m or 375 m pixel that "changed" between Monday and Tuesday is usually the weather. The Sentinel-2 tool exists specifically because that is not a finding.
Decade search, and the years WELD does not have
A 30 m HLS anniversary is not the same calendar day every year. That date often has no overpass, or clouds. The desktop tool walks about a month either side and keeps the least cloudy scene, so a decade film is one clear picture per year rather than ten empty Tuesdays.
Landsat WELD in GIBS is not 1984–2011. It is nine annual mosaics, dated 1 December: 1983–85, 1988–90, and 1998–2000. Asking for any other year returns a black frame with a coastline drawn on it. The preview's WELD layer only scrubs those nine dates. Active-fire dots do not exist before 2012; the desktop tool drops that overlay instead of failing the picture.
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