# Carr: Great Circles, Modified Great Circles, Rhumb Lines, and Bucket Routes

**URL:** <https://forum.gcaptain.com/t/carr-great-circles-modified-great-circles-rhumb-lines-and-bucket-routes/61638>\
**Category:** Marine Weather\
**Created:** [December 9, 2021, 12:38pm UTC](https://forum.gcaptain.com/t/carr-great-circles-modified-great-circles-rhumb-lines-and-bucket-routes/61638 "2021-12-09T12:38:34Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Kennebec\_Captain](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.gcaptain.com/kennebec_captain/32/13_2.png) [@Kennebec\_Captain](https://forum.gcaptain.com/u/Kennebec_Captain)\
**Post date:** [December 9, 2021, 12:38pm UTC](https://forum.gcaptain.com/t/carr-great-circles-modified-great-circles-rhumb-lines-and-bucket-routes/61638/1 "2021-12-09T12:38:34Z")

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> **[Carr: Great Circles, Modified Great Circles, Rhumb Lines, and Bucket Routes](https://gcaptain.com/carr-great-circles-modified-great-circles-rhumb-lines-and-bucket-routes/)**
>
> By CW4 Michael W. Carr, US Army Watercraft Master (Retired) All too frequently we read on gCaptain about vessels losing containers when impacted by high seas. Of the six motions...

Our charterer required we use weather routing for ocean transits during the winter months, it was optional otherwise. The way it worked is the routers would first ask me what route I planned and I’d send them my planned route. Mostly they’d agree with my proposed route. Sometimes they’d recommend some modifications along with the rational behind the recommendations.

If I didn’t agree or understand I’d send them an email.

I never had any significant weather issues on an ocean transit nor any out of the ordinary delays.

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**Author:** ![fredwx](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.gcaptain.com/fredwx/32/3873_2.png) [@fredwx](https://forum.gcaptain.com/u/fredwx)\
**Post date:** [December 10, 2021, 3:16am UTC](https://forum.gcaptain.com/t/carr-great-circles-modified-great-circles-rhumb-lines-and-bucket-routes/61638/2 "2021-12-10T03:16:17Z")

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The 500mb forecast chart is an excellent tool for mariners to estimate where to anticipate the heaviest sea and swell conditions as well as a guide to the expected surface storm tracks and intensities. [http://oceanweatherservices.com/blog/2019/12/10/use-500-mb-chart-sea/](http://oceanweatherservices.com/blog/2019/12/10/use-500-mb-chart-sea/)