Claim
What was supposed to happen
Define the intervention, timing, location, expected physical response, and claimed climate effect.
Fair Sky independently evaluates claims about deliberate changes to the atmosphere, including what happened, what effect it had, and how certain we can be, using satellite observations, atmospheric data, and physics-based models.
Every claim follows the same logic: define the intervention, establish what should be observable, compare it with independent measurements, quantify uncertainty, and issue a defensible verdict.
Define the intervention, timing, location, expected physical response, and claimed climate effect.
Construct a local or global background state from observations, reanalysis, and historical variability.
Use independent satellite or in-situ observations to detect the relevant physical signal.
Separate the claimed effect from meteorology, natural variability, other sources, and retrieval uncertainty.
Report effect size, confidence, uncertainty, data provenance, and the evidence behind the conclusion.
The organization proposing or operating an atmospheric intervention should not be the only organization measuring whether it worked. Fair Sky is designed as an independent verification layer: observation-first, uncertainty-aware, and separate from intervention operations.
Fair Sky does not deploy atmospheric interventions and does not advocate for or against their use. We independently evaluate whether claimed atmospheric effects occurred and quantify the evidence, uncertainty, and attribution.
We start with three use cases: verifying contrail avoidance, detecting marine cloud brightening above natural variability, and establishing the stratospheric aerosol baseline against which future interventions can be evaluated.
An airline claims a reroute avoided a warming contrail. We test whether the observed atmosphere, flight trajectory, and counterfactual support that claim, with uncertainty.
Open contrail demo →An operator claims a field intervention changed cloud properties. We test whether the signal is detectable above natural variability and retrieval uncertainty.
Open MCB demo →An operator reports a stratospheric perturbation. We establish the background aerosol state and test whether the anomaly can be independently detected and attributed.
Open baseline demo →Fair Sky provides independent evidence for organizations making, buying, evaluating, or standardizing claims about atmospheric interventions.
Independent observational validation for forecasting and rerouting products. Verify whether predicted avoidance translated into observed atmospheric outcomes.
Defensible evidence for contrail-avoidance and warming-avoidance claims, with uncertainty carried from the observed event through the estimated climate effect.
Reproducible methods for counterfactual design, detectability, attribution, and uncertainty, providing the measurement foundation needed for auditable intervention protocols.
Independent assessment of field experiments and atmospheric interventions, from marine cloud brightening to stratospheric aerosols.
We combine aircraft trajectory, atmospheric conditions, satellite observations and aircraft metadata to identify persistent contrails and verify whether mitigation worked.
Persistent warming contrail observed and attributed with high confidence.
Compare the observed flight with the lowest-cost alternative trajectory.
Persistent contrail observed.
77% lower estimated contrail climate impact.
Retrospective verification prototype inspired by published Great Barrier Reef field work. The published trial demonstrated transport of artificially generated sea-salt aerosol to cloud-base height; the satellite-response values in this interface are illustrative.
Fair Sky compares the intervention scene with meteorologically matched control clouds, then asks whether the retrieved microphysical or radiative change exceeds background variability and retrieval uncertainty.
The sign of the response is consistent with brightening, but the estimated signal does not clearly exceed the matched-cloud variability envelope.
A verification baseline needs more than one sensor. The dashboard tracks aerosol extinction, integrated stratospheric aerosol optical depth, altitude, latitude, wavelength, event history, and cross-instrument disagreement.
A production version would ingest current observations and maintain a continuously updated background distribution by latitude, altitude, wavelength, season, and recent volcanic/fire activity.
No intervention claim is being tested. This state defines the aerosol background and expected cross-sensor spread against which a future anomaly would be judged.
We compare independent satellite measurements of the stratospheric aerosol state. Their agreement determines how confidently we quantify the aerosol enhancement and its resulting cooling effect.
Range reflects both measurement disagreement and model spread.
We’re building an independent atmospheric verification layer for claims involving deliberate changes to the atmosphere. If you’re an airline operator, verifier, flight-planning provider, corporate travel buyer, researcher, or potential partner, we’d love to hear from you.
Tell us what you’re working on and where independent contrail verification could help.
Email Fair Sky