JTides Help

JTides is Copyright © 2006, P. Lutus. All rights reserved.

JTides is CareWare. Please read about CareWare at www.arachnoid.com/careware.

The JTides home page is located at www.arachnoid.com/JTides.

NOTE: Now that JTides is being sold by criminals regularly,
I want to emphasize that JTides is free, it is not for sale,
and if someone tries to sell it to you, call the police and report the theft.

Introduction

JTides is a very powerful tidal prediction program with a worldwide database of tide and current reporting stations. It can produce daily tidal graphs with minute-to-minute predictions and many additional display options. It can display and print monthly tide calendars. It even has a month chart in color, where the colors represent the tidal heights at different times. You can click this color chart for a specific forecast.

Every effort has been made to assure that JTides is easy to use. Your preferences are remembered between uses, including a list of your favorite sites for easy recall.

In most cases, JTides produces the same results as printed tide tables. This is not surprising, as JTides uses the same data sources as the compilers of the printed tables. This means JTides can be an appropriate substitute for a printed table (and be sure to read the accuracy warning below, which applies to both). And JTides continues to provide accurate tidal predictions for years to come (for most locations, until 2038).

JTides is written in Java, so no matter what computer or operating system you have, chances are JTides will run on it.

Credits

The tidal and current data files used by JTides have been acquired from various sources, but the single most important source has been the Xtide project. In fact, the Xtide project (http://www.flaterco.com/xtide) has done more to make this program possible than I have, if the truth be known. It is not easy to write a modern, graphical computer program, but the effort that went into collecting and formatting the tide data tables used by JTides is much greater.

To summarize, for the success of this program I am indebted to all those unnamed people who struggled to create the tide data tables. And also -- very important -- much of the data, and some of the mathematical methods, are derived from government-funded sources, so they are not part of my copyright protection.

Some of the the data used in JTides has been derived from sea level data obtained from the British Oceanographic Data Centre based at the Proudman Oceanographic Laboratory, Liverpool, and is provided on the condition that JTides remain a free program.

Caveats

Please read the next part very carefully. Sitting down? Feeling comfortable?

Tidal and current prediction can be a very imprecise business. Here are some of the factors that might make a tide and/or current prediction incorrect:
  1. Weather. Low barometric pressure and onshore winds tend to make the tide higher than predicted. High barometric pressure and offshore winds tend to make the tide lower than predicted. Hurricanes, well ... use your imagination.
  2. Human error. There are several ways human error can spoil a tide prediction. Imperfect mathematical modeling, errors in data collection, and typographical errors all contribute.
  3. Geographical changes. Tidal data tables tend to go out of date over time in some areas with a lot of human activity. This is because we are constantly reshaping the landscape, an activity that changes the way water moves across the land.
Therefore (ahem), do not rely solely on this program's results if lives or safety are at stake. I have done my best, but there are too many factors that might contribute to an error. You are solely responsible for determining whether this program can be trusted to provide accurate results. It should never be exclusively relied on to assure the security of life or property.

Got that? Good.

Here is a list of help sections -- click the one you want to read:

Setup |  Basic Operation |  Display Options |  Site Explorer |  Nearest Site Finder |  Data Export Options |  Data Sources
Configuration |  Time Issues |  Technical Background