The Climate Question · Investigation · Observed
Is it already stressing ecosystems? Read the record.
Not a forecast — a measurement. About 1C of warming has already reorganized ocean chemistry, put the world's reefs into a fourth bleaching event, shrunk ice, and started moving species off the map.
FACT
§2 · Thesis
One degree sounds trivial; its effects aren't, because the systems it acts on respond at thresholds, not in smooth lines.
Corals bleach past a line; ice melts past a line; a small average shift turns rare extremes into regular ones.
The number
~84%
of the world's coral reef area hit by bleaching-level heat stress in the fourth global bleaching event (2023–2025), confirmed by NOAA in April 2024 — up from 68% in 2014–2017.
NOAA; NOAA Coral Reef Watch / ICRI
§5 · Graded Claim
The planet has warmed ~1C since the late 1800s — about 10 times faster than a natural post-ice-age warming; the IPCC calls human influence 'established fact.'
FACT
Most of the rise is recent, and the warmest years are all recent.
§5 · Graded Claim
The ocean absorbed ~90% of the extra heat; its top 100 m warmed ~0.33C since 1969 and heat content is setting records.
FACT
Air temperature understates the total heat added; a warmer ocean expands, deoxygenates, and drives marine heatwaves.
§5 · Graded Claim
The surface ocean is ~30% more acidic than before the industrial revolution — pH down 0.1 units, a pole-to-pole chemistry change.
FACT
The pH scale is logarithmic, so a 0.1-unit drop is ~30% more acidity; it impairs corals, oysters and other shell-builders.
§5 · Graded Claim
Species are already shifting ranges poleward and upslope and changing seasonal timing, and the first climate-driven extinctions are recorded.
FACT
IPCC AR6 Working Group II (2022 SPM) finds widespread observed impacts on nature across thousands of species — observed, not projected.
§6 · Record vs Narrative
Observed vs. projected — we stay on the left.
Measured (graded FACT here)
- Ocean +heat, +30% acidity; reefs in a 4th bleaching event.
- Ice sheets losing mass; seas rising.
- Species ranges and timing already shifting.
Risks (not asserted as fact)
- Ecosystem collapse and crossed tipping points.
- Single-event blame ('this storm was climate').
- Specific future magnitudes — ranges, not certainties.
Declassified
'Stressed' is documented; collapse and crossed tipping points are risks with real uncertainty — not asserted here.
§7 · Why it matters now
Why this page comes before the cost fight.
Whether it's 'worth' fixing depends on what is already being lost. A degree of warming has reorganized ocean chemistry, bleached the world's reefs, and started moving species. The next spokes in The Climate Question take up 'too expensive?' and the objections to solar and wind — arguments that only make sense once the size of what's already happening is on the table.
▸ The Climate Question →
▦ Ledger gaps
Help us fill these lines.
- OpenThe costs of action vs inaction — the next spoke.
- OpenHow much of today's extreme-weather burden is already attributable, region by region.
Help fill these →