Seventeen years ago today, on December 31st 1994, almost 9,000 residents of the nation of Kiribati found themselves in January 1st 1995. For those people the date of December 31st 1994 would never exist.
This was not a natural phenomenon.
The nation of Kirabati consists of some 726 square kilometers of land spread out over 33 million square kilometers of ocean. Half the nation (including the uninhabited Starbuck Island) was on one half of the international data line, and the other half, including the capitol were west of the line. This was somewhat inconvenient, so the line was moved over from the 180th meridian to just east of the 150th meridian.
To put this into perspective New York City is just east of the 75th meridian, and Los Angeles is just east of the 120th meridian. The date-line was moved two thirds of the distance from LA to NYC, or roughly the distance from LA to Chicago.
Kirabati is one of the least developed nations in the world. Their easternmost island, formerly Caroline Island, became the first location to see the sun on January 1st 2000, and so was the first location headed into the new millennium. Caroline Island was re-named Millennium Island. Caroline Island is home to a large population of potentially endangered Coconut Crabs, and no people.
The residents of Kirabati face the consequences of another potentially important unnatural phenomenon. Since most of the islands are at sea level any significant rise in sea level would make them disappear entirely.