Claim
What was supposed to happen
Define the intervention, timing, location, expected physical response, and claimed climate effect.
Fair Sky combines satellite observations, atmospheric data, and physics-based models to test whether an intervention produced the effect it claims — from contrail avoidance to marine cloud brightening and stratospheric aerosols.
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.
Our first demos cover aviation contrails, marine cloud brightening, and the stratospheric aerosol baseline that future intervention claims would have to beat.
An operator says a reroute avoided a warming contrail. We compare the actual trajectory, atmospheric conditions, satellite observations, and a counterfactual route — with uncertainty.
Open contrail demo →Test whether an aerosol release produced a detectable change in cloud droplet size, optical depth, or reflectivity above natural cloud variability.
Open MCB demo →Establish the background aerosol state and quantify whether a future perturbation is distinguishable from volcanic, wildfire, and retrieval-driven variability.
Open baseline demo →The same evidence layer can serve operators, researchers, regulators, funders, insurers, and buyers who need an independent answer to a simple question: did the claimed effect actually occur?
Meet mandatory non-CO₂ reporting, target the small share of flights that drive most contrail warming, and verify that avoidance actions actually reduced impact.
Pre-register observables, establish a defensible baseline, and evaluate whether field experiments produce a measurable atmospheric response.
Independent, observation-backed evidence with explicit uncertainty, provenance, and reproducible methods.
Evaluate claims without relying solely on the intervention operator’s own model, measurement system, or success criteria.
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 until the retrieval pipeline is connected to MODIS/VIIRS data.
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’re building independent measurement, reporting, and verification for atmospheric climate interventions. 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