How Old Is the Data on Your SST Chart?

It depends which product you're looking at. A raw satellite pass is typically a few hours old by the time it reaches Chlorofishy. The SST composite runs on a measured publish lag of about 34 hours; the chlorophyll composite, roughly 12 to 14 hours. Neither figure is an estimate: both come from a 13-day measurement against the live pipeline.

Why the composite lags

A composite (see raw pass vs. composite) has to wait for the day's full set of source passes to arrive before it can be blended into one gap-free field. That collection-and-processing step is why NASA's GHRSST MUR SST analysis consistently publishes about a day and a half after the observation date, and why the VIIRS chlorophyll composite runs faster: it's built from fewer sources with a simpler pipeline.

Why a raw pass is fresher

A pass skips the blending step entirely: it's one satellite's one overflight, published as soon as it's processed. Chlorofishy's pipeline checks every source for new passes every 10 minutes, around the clock, so a fresh overflight typically appears on the map within a few hours of the satellite actually crossing that patch of ocean. The tradeoff is coverage, not freshness. See why your chart is blank.

How to check the age of any specific chart

Every layer on Chlorofishy's map carries its own capture time and satellite name, visible in the provenance panel, never a generic “updated today.” If ingest ever fails, the frontend is built to say so rather than silently show stale data as current. See using the timeline for how to read capture times on the map itself, and data sources for the full latency table by product.

Check today's actual data age on the ocean temperature map for any region, or see how our published latency compares to a named competitor on Chlorofishy vs. Terrafin. Back to Learn.