Timezones are impossible

This video was linked on the Emacs Org-mode mailing list.  The discussion was about an desire to incorporate timezones into some particular org-mode feature, or another.  This is relevant somehow.  It's beyond my realm.  That said, I love it.

https://www.youtube.com/watch?v=-5wpm-gesOY

Tide machines

 Just one image among many on the Internet, of a tide machine, together with Arthur Doodson, who used such tide engines to profile the tides at Normandy for D-Day.  

 

This article, from the shipyard blog, about the tide predictions for D-Day, presents high quality images of several versions of tide machine, and an excellent story.

The Battle of Tarawa, however, in The Gilbert Islands, is an example of tide predictions gone wrong. 

Dodge tides

 

The Australian term Dodge Tide refers to a time when at least one tide is skipped, during a neap tide.   

 

A popular description of Dodge Tides at Gulf St. Vincent, Adelaide Region, South Australia: 

https://www.abc.net.au/news/2017-02-17/the-story-behind-adelaides-dodge-tides/8279870

  

Another view showing a Dodge Tide at Adelaide:

 

Another site, like Adelaide in Gulf St. Vincent, is Edithburgh, which has a more striking Dodge Tide is exhibited.  

 

 Tide tables are not useful, at such locations. 

It's the Earth, on Earth Day

 A link to a National Geographic webpage: Milestones in Space Photography.

 

Can we agree that our home is a very, very fine home, and that we must do everything we can to preserve and conserve it?   

Several images of the Earth from space are nicely presented here.

Earth Rise

This image is of Earth Rise from the Moon is widely touted as a spark that started the Environmental Movement.  True or Not, such photographs as these have inspired many of us to reconsider the fate of our trash.

Astronauts have commented that our atmosphere appears from space as a thin layer, approximately at the same scale as a layer of paint on a basketball.  

 

Juxtaposed photographs, another approach to visualization of high and low tides.

An alternative approach to visualization of tides has been provided by Ron Hipschman, of San Francisco's Exploratorium.  A friend had asked, wasn't there a more direct way to portray the high and low tides, than a graph, or just numbers?  

These two panoramas were compiled from series of photographstaken at high and low tide.  The subject is Pier 15 (site of the Exploratorium), on the left, and Pier 17 on the right, at San Francisco.   I don't know the dates and times.  These were obviously taken from out in the Bay, probably from a boat.  How else?

Satellite Altimetry: Tide Gauge Network on Steroids // Sea Level Rise

 This article caught my eye.  

 

 https://earthobservatory.nasa.gov/images/147435/taking-a-measure-of-sea-level-rise-ocean-altimetry

 

Here's a link to the whole Earth Observatory Sea Level Rise collection 

 

I am remembering that in 1996, when I started teaching Environmental Science on the island of Saipan, it was difficult to find news articles online to print for student use.  There were very few.  Even before this, I had taught Environmental Science for a number of years in Chuuk Lagoon, predating, I think, the Internet.  Needless to say, there was Zero presence of news articles about Sea Level Rise.

Sadly, there are places on the globe, even today, where sea level rise is an actual fact of every day life, but where no Internet resources are available to educate or prepare the islanders or their decision making leaders.  

It is a profoundly obscene actuality: publishers of scientific journals want to charge even those islanders---assuming any ability to access them through the Internet---up to or more than 52.00 for a single article.  These islanders do not use or carry money.  

Such arrogance.  How arrogant we are.

Declination of the Sun

Over the course of a year, to an observer on Earth, the Sun travels from extreme North in June to South in December, and back again.  The Seasons are determined by these changes in the Declination of the Sun---its angle North or South of the Equator.  Tides respond to the Declination of the Sun as well.   The following animation was constructed from photographs of the Earth over time from the  perspective of an observer beyond the Solar System..  . 

 

https://twitter.com/weatherdak/status/1274383843215110145

 

In reality, it is the Earth that is moving, relative to the Sun.