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Recordedrangeclimate

Mass bleaching on the Great Barrier Reef

Aerial and underwater surveys of over eleven hundred reefs across the Great Barrier Reef in March and April 2016 found that only a small minority — around nine per cent of reefs surveyed — escaped bleaching altogether, with the most severe bleaching concentrated in the northern third of the system, the section that had been least affected by earlier disturbance and was widely assumed to be the most remote and therefore the safest. Follow-up surveys later that year recorded the loss of a large share of shallow-water corals in the worst-affected northern sector. The event is the pivot of this Journey because it broke the assumption that distance from human pressure confers protection: the northern reefs bleached most precisely because they were furthest from anything that could have been managed.

Observed — measured or witnessed, with the observation cited.

Subjects

Evidence

Partly verified — Core facts are sourced; some optional detail is deliberately absent. This is the standing of the weakest source, not an average.

Recorded on Great Barrier Reef

  1. Darwin publishes The Structure and Distribution of Coral Reefs
  2. The Great Barrier Reef is inscribed on the World Heritage List
  3. Mass synchronous spawning described on the Great Barrier Reef
  4. The Long-Term Monitoring Program begins annual reef surveys
  5. The first global mass bleaching event
  6. A published projection that reefs would bleach faster than they could recover
  7. A measured decline in Great Barrier Reef coral calcification is published
  8. Twenty-seven years of monitoring show coral cover roughly halved
  9. The third global bleaching event
  10. Mass bleaching on the Great Barrier Reef
  11. A second consecutive year of mass bleaching on the Great Barrier Reef
  12. The interval between severe bleaching events is measured, and it has collapsed
  13. The fourth global bleaching event is confirmed

Related

Related because they share a subject in the Atlas — never because the text looks similar.