TerraSignal is a subscription web service that aggregates public geophysical data streams — geomagnetic field measurements, seismic events, ocean-temperature trends, solar activity indices, ionospheric conditions, Earth-rotation axis position — and displays them in a single dashboard.

The service computes a composite Anomaly Index (0–100) and per-stream z-scores from that data. When enough streams deviate simultaneously from their historical baselines, the index rises. A Sentinel-tier subscriber may also opt in to receive SMS alerts when specific rules fire.

The full methodology — every source URL, every formula, every scoring threshold — is documented at /methodology.

To create a TerraSignal account you must:

• Be at least 18 years old.
• Provide a valid email address you control.
• Maintain only one account per person. Multiple accounts to circumvent tier limits are grounds for suspension.
• Not share your login credentials or API keys with other individuals. If you need multi-seat access, contact us.

You are responsible for keeping your account secure. Changing your password immediately invalidates all other logged-in sessions across devices — use that if you suspect unauthorized access.

TerraSignal offers three tiers. Free access requires no card. Paid tiers are billed monthly through Stripe.

• Free — live anomaly index, 30-day history, last 3 alerts. No cost. No card required.
• Monitor — $12/month. Full component breakdown, 90-day + 1-year history, extended charts, full alert history, SMS on critical alerts.
• Sentinel — $30/month. Everything in Monitor plus API access, CSV/JSON data export, and custom alert thresholds.

Renewals. Paid subscriptions auto-renew at the end of each billing period until canceled.

Cancellation. Cancel anytime from /account. Your paid tier remains active through the end of the current billing period; you are not charged again.

Refunds. If you cancel within 7 days of a new subscription (or a tier upgrade) and have received no material value from the tier — e.g., no SMS alerts delivered, no API keys generated — email us for a full refund. Outside that window, subscriptions are non-refundable but you retain access through your paid period.

Price changes. If we raise prices, existing subscribers get 30 days’ notice by email before their next billing cycle at the new rate. You may cancel before the price takes effect.

SMS alerts are available to Monitor and Sentinel subscribers who verify their phone number on the /account page.

You agree not to:

• Scrape or hit the API faster than the published rate limits (or, for the free public dashboard, faster than what an individual using a browser would generate).
• Attempt to reverse-engineer the scoring math, alert-rule thresholds, or internal API contracts beyond what is publicly documented at /methodology and /docs.
• Attempt to gain access to accounts other than your own, probe for vulnerabilities without prior written consent, or interfere with the operation of the service.
• Republish or redistribute TerraSignal data, scores, or alert messages as if they are your own, or represent them as predictions or forecasts.
• Use TerraSignal in any manner that violates applicable law in your jurisdiction.

Sentinel-tier API keys allow programmatic use of your paid entitlements — that is expressly permitted, within the published rate limits.

TerraSignal is provided “AS IS” and “AS AVAILABLE” without warranties of any kind, express or implied. That includes, without limitation, warranties of accuracy, completeness, fitness for a particular purpose, uninterrupted availability, or non-infringement.

TerraSignal aggregates data from upstream providers that we do not operate:

• USGS (earthquake catalog + magnetometer relay)
• NOAA SWPC (space weather, Kp, Dst, solar wind, x-ray flux)
• INTERMAGNET (geomagnetic observatories)
• GFZ Potsdam (Kp nowcast)
• SILSO / SIDC (sunspot number)
• Argovis + Argo (deep-ocean temperature profiles)
• IERS (Earth-rotation axis position)
• CODE (global ionospheric TEC)

Any of these can be temporarily unavailable, change endpoint URLs, publish delayed data, or serve incorrect values. When that happens, TerraSignal’s displayed values reflect the upstream reality — including gaps, staleness, or errors. We monitor for these situations via the internal canary system and fix source-side issues as we detect them, but we make no guarantee of specific uptime or accuracy.

To the maximum extent permitted by law, TerraSignal’s total liability for any claim arising from your use of the service is capped at the fees you have paid TerraSignal in the 12 months preceding the claim. For a Free-tier user, that cap is zero.

TerraSignal is not liable for indirect, consequential, incidental, special, exemplary, or punitive damages of any kind — including, without limitation, lost profits, lost data, business interruption, or damages resulting from actions you took or did not take in response to information displayed on the service.

Some jurisdictions do not allow the exclusion or limitation of certain damages. Where such laws apply, TerraSignal’s liability is limited to the smallest amount permitted by that law.

By you. You may cancel your subscription or delete your account at any time from /account. Account deletion is immediate and irreversible — see the data retention section of the privacy policy.

By TerraSignal. We may suspend or terminate your access to the service if you materially breach these terms, attempt to abuse or attack the platform, or use the service in a way that harms other users. Where possible we will notify you by email first with an opportunity to cure the issue; some breaches (active attacks, credential abuse) warrant immediate suspension without notice.

If we terminate a paid account other than for breach, we refund the unused portion of the current billing period.

These terms are governed by the laws of the State of Utah, USA, without regard to its conflict-of-laws principles. Any legal action related to these terms or TerraSignal will be brought in the state or federal courts located in Salt Lake County, Utah, and you consent to that jurisdiction.

If you are accessing TerraSignal from outside the United States, you are responsible for complying with your local laws. We do not currently offer a separate legal framework for EU/UK, but we honor the substance of GDPR-style access, correction, and deletion rights — see the privacy policy.

When these terms change materially, we update the effective date at the top and notify active users by email at least 14 days before the change takes effect. Continuing to use the service after the effective date constitutes acceptance of the updated terms. If you do not accept the changes, you can cancel your subscription and delete your account before the effective date.

Non-material changes (wording, typo fixes, clarifications, added examples) may go in without notice.

Legal questions, notices, or account issues:

terrasignal.contact@gmail.com

TerraSignal is operated by Gabriel Robinson, a sole proprietor based in Utah, USA.