RESEARCH PROJECT — UNDER DEVELOPMENT

This application is an active research project under development. It is not a finished product, not a navigation tool, and not validated against measured conditions at the Merrimack River bar. It is shared publicly so that experienced mariners can evaluate the approach, identify errors, and contribute to its improvement. All output should be treated as experimental.

Spending time on the Merrimack River in Newburyport, Massachusetts, you quickly understand why its mouth is considered one of the most dangerous river entrances on the New England coast. On days that appear modest offshore, the bar can produce steep, breaking waves that rise with little warning. The conditions are notoriously unpredictable, and that unpredictability has real consequences.

U.S. Coast Guard Station Merrimack River is one of only 19 designated surf stations in the country. This designation is reserved for locations that experience breaking surf greater than eight feet more than 36 days each year. The Merrimack earns that designation consistently.

What makes this river mouth so difficult is that its conditions are not driven by offshore forecasts alone. They are the result of interacting forces. Wind speed and direction, tidal phase, river discharge, and the geometry of the inlet all combine to shape what happens at the bar. The underlying physics are well understood. Wave-current interaction, shoaling, and tidal hydraulics have been studied for decades. The gap is in application. No existing tool assembles these factors into a system that models the reality of this specific location. A mariner can review standard forecasts on a relatively calm day and still encounter standing, breaking waves in the channel.

My name is Caleb Barlow. I am an engineer and an avid fisherman on the Merrimack. Like many who navigate this river, I have learned its lessons through experience, and sometimes through close calls. I have buried the bow of my boat beneath breaking surf multiple times. I have learned the L approach along the North Jetty. I have also arrived at the mouth with a boat full of kids on what appeared to be a calm day, only to turn around after seeing conditions that no forecast had prepared me for. I have spent years thinking about this problem. Why is there no tool that reflects what actually happens here?

The challenge was not a lack of theory. The challenge was applying it in a way that captures the complexity of this specific river. Translating physical principles into a working model of the Merrimack is not something that can be done by hand. It requires combining multiple interacting systems and tuning them to local conditions. That became possible with the use of modern artificial intelligence.

This research project is not another weather app. It does not simply report offshore wave height or wind speed. It is an attempt to build a working model of the river itself. Built with AI, it integrates the physics of wave formation, current interaction, and tidal behavior with the actual geometry of the inlet. The system evaluates wave height, steepness, and period alongside tidal state and river flow to estimate how waves may form and behave at the mouth.

The model is being calibrated using real-world feedback. Predictions are compared against camera footage of the river entrance and detailed accounts from experienced captains. A high-resolution side-scan sonar survey of the bar at approximately one foot resolution was conducted to provide bathymetric detail far beyond what is available in public charts, allowing the model to reflect the true shape of the riverbed.

The project now spans more than 5,000 lines of code and continues to improve as new data is incorporated. Nearly every year this river claims lives. The goal of this research is to explore whether a model of this kind, calibrated to local conditions, can someday give mariners one more tool to make better-informed decisions. That goal has not yet been reached, and the application should be evaluated with that in mind.

IMPORTANT SAFETY NOTICE — PLEASE READ BEFORE USE

Merrimack Boats Wave Calculator (the "Application") is a research project that estimates wave height and bar crossing conditions at the mouth of the Merrimack River in Newburyport, Massachusetts. It is provided for general informational and research purposes only. It must not be used as the basis for any navigation or crossing decision.

1. Research Status
This Application is an active research project under development. The wave height model, its calibration constants, and its methodology have not been independently validated against measured Merrimack bar conditions. Outputs are experimental estimates subject to significant uncertainty and may contain errors that are not obvious.

2. AI-Assisted Development
This Application was developed with extensive use of artificial intelligence. AI systems are known to produce errors, omissions, and confident-sounding but incorrect outputs, a phenomenon commonly referred to as "hallucination." Users should treat all outputs as estimates subject to significant uncertainty and verify all conditions through independent means.

3. Not For Navigation
The Application is not a navigation tool. It must not be used for navigation of any kind, including but not limited to bar crossing decisions, route planning, departure or return decisions, or any operational decision aboard a vessel. The Application is not a substitute for direct visual observation of bar conditions, official forecasts from the National Weather Service, U.S. Coast Guard guidance, marine charts, or the judgment of an experienced mariner with current local knowledge.

4. Eligibility
You must be at least 18 years of age to use this Application. By using the Application you represent and warrant that you meet this requirement.

5. Acceptable Use
You agree not to:

• Use the Application for navigation of any kind.
• Use the Application as the sole or primary basis for any decision involving safety of life or property.
• Redistribute, republish, mirror, rehost, or otherwise make the Application or its output available to third parties.
• Scrape, crawl, harvest, or otherwise programmatically extract data from the Application or its underlying services, except as a normal end-user accessing the user interface.
• Use the Application for any vessel operation or as input to any emergency response decision.

6. Assumption of Risk
Crossing the Merrimack River bar involves inherent and serious risk, including risk of death, injury, and vessel loss. People have died on this bar in conditions that appeared manageable from offshore. By using this Application you acknowledge that you understand this risk and that you assume full and sole responsibility for all decisions you make on or near the water.

7. Limitation of Liability
The Application is provided "AS IS" and "AS AVAILABLE" without warranty of any kind, express or implied, including without limitation any warranty of merchantability, fitness for a particular purpose, accuracy, or non-infringement. To the fullest extent permitted by law, Caleb Barlow and any associated parties shall not be liable for any direct, indirect, incidental, special, consequential, or punitive damages, including without limitation damages for personal injury, death, vessel damage, lost profits, or loss of data, arising out of or in connection with your use of or inability to use the Application, whether based in contract, tort, strict liability, or otherwise, even if Caleb Barlow has been advised of the possibility of such damages.

8. Indemnification
You agree to indemnify, defend, and hold harmless Caleb Barlow and any associated parties from and against any and all claims, liabilities, damages, losses, costs, and expenses, including reasonable attorneys' fees, arising out of or in any way connected with your use of the Application, your violation of these terms, or your violation of any rights of any third party.

9. Governing Law
These terms shall be governed by and construed in accordance with the laws of the Commonwealth of Massachusetts, without regard to its conflict of law principles. Any dispute arising out of or relating to these terms or the Application shall be subject to the exclusive jurisdiction of the state and federal courts located in Massachusetts.

10. Severability
If any provision of these terms is held to be invalid or unenforceable, the remaining provisions shall remain in full force and effect.

11. Changes
These terms may be updated from time to time without prior notice. Continued use of the Application after any change constitutes acceptance of the updated terms.

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