The term above mean sea level (AMSL) refers to the elevation (on the ground) or altitude (in the air) of any object, relative to the average sea level datum. AMSL is used extensively in radio (both in broadcasting and other telecommunications uses) by engineers to determine the coverage area a station will be able to reach. It is also used in aviation, where most heights are recorded and reported with respect to AMSL (see flight level), and in the atmospheric sciences.

The concept of a "mean sea level" is in itself rather artificial, because it is not possible to determine a figure for mean sea level for the entire planet, and it varies quite a lot even on a much smaller scale. This is because the sea is in constant motion, affected by the high and low pressure zones above it, the tides, local gravitational differences, and so forth. The best one can do is to pick a spot and calculate the mean sea level at that point and use it as a datum. For example, the Ordnance Survey uses a height datum based on the measurements of mean sea level at a particular gauge at Newlyn, Cornwall from 1915 to 1921 for their maps of Great Britain, and this datum is actually some 80 cm different from the mean sea level reading obtained on the other side of the country. An alternative is to base height measurements on an ellipsoid of the entire earth, which is what systems such as GPS do. In aviation, the ellipsoid known as World Geodetic System 84 is increasingly used to define mean sea level. Another alternative is to use a geoid based datum such as NAVD88.

Mean sea level (MSL) is a measure of the average height of the ocean's surface (such as the halfway point between the mean high tide and the mean low tide); used as a standard in reckoning land elevation. MSL also plays an extremely important role in aviation, where standard sea level pressure is used as the measurement datum of altitude at flight levels.

To an operator of a tide gauge, MSL means the "still water level"—the level of the sea with motions such as wind waves averaged out—averaged over a period of time such that changes in sea level, e.g., due to the tides, also get averaged out. One measures the values of MSL in respect to the land. Hence a change in MSL can result from a real change in sea level, or from a change in the height of the land on which the tide gauge operates.

In the UK, the Ordnance Datum (the 0 metres height on UK maps) is the mean sea level measured at Newlyn in Cornwall between 1915 and 1921. Prior to 1921 the datum was MSL at the Victoria Dock, Liverpool.

In France, the Marégraphe in Marseilles measures continuously the sea level since 1883 and offers the longest collapsed data about the sea level. It is used for a part of continental Europe and main part of Africa as official sea level.

Jean-Thenistor Pascal (born October 28, 1982 in Port-au-Prince, Haiti) is a Haitian-Canadian professional boxer. He is a former WBC and The Ring Light Heavyweight Champion.

When Pascal was 4, his mother (a nurse) and older brother (Nicholson Poulard) left Haiti for a better life and education. They settled in Laval, Quebec, just outside of Montreal. His father, a well-respected politician, remained in Haiti. Pascal played hockey and soccer, but after watching his older brother become the Quebec Boxing Champion in 1996, Pascal, at 13 years of age, started to visit boxing gym "Club Champions St-Michel" once or twice every week. His first trainer was Sylvain Gagnon, who considered Pascal to be very talented. According to an interview from May 2005, Pascal's idol was Roy Jones Jr..

He represented Canada as a middleweight at the 2004 Olympics in Athens.

Pascal made his professional debut on February 3, 2005, defeating Justin Hahn by second round technical knockout. After nine professional fights, Pascal fought for the Canada National Super Middleweight title and the Quebec boxing Council (CQB) title in a national bout against Martin Desjardins, winning the fight by KO 7. After two more fights Pascal bagged the TAB (Trans America Boxing) Super Middleweight title against Darnell Boone in his first ten round contest. Soon after Pascal fought Lucas Green Arias on September 30, 2006, at the Montreal Casino. The fight was for the vacant WBC Latino Super Middleweight title. Pascal sent him to the canvas with a flurry of punches in the sixth round. Arias got up for the final second of the round, but moments later slid off the stool in his corner, vigorously rubbing his head. He was unable to get up for the seventh round, making Pascal the winner. He was given oxygen in the ring and then was taken to the hospital on a stretcher. It was revealed that he suffered a subdural hematoma.

Lucian Bute (born February 28, 1980) is a Romanian-Canadian professional boxer fighting out of Montreal, Canada. Bute is a former IBF Super Middleweight Champion. BoxRec has previously ranked him as the 9th pound for pound best boxer in the world and number 2 at super middleweight in 2012, after Andre Ward.

Lucian Bute was born on February 28, 1980 in Pechea, Galaţi County, Romania.

He also holds Canadian citizenship, gained in 2012.

As an amateur, Bute won the bronze medal at the 1999 World Amateur Boxing Championships in Houston, Texas and the Gold Medal at the 2001 Francophone Games. Bute also represented Romania at the 2003 World Amateur Boxing Championships in Bangkok, Thailand as a middleweight.

Lucian Bute turned pro in 2000. He is still trained by Stéphan Larouche, who also trained former world champions Éric Lucas and Leonard Doroftei.

On June 15, 2007, Bute faced super middleweight contender and former Olympian Sakio Bika at the Bell Centre in Montreal in an elimination bout for the IBF title. Bute beat Bika by unanimous decision (116-111, 118-109, 118-109) and, as a result, he got his shot at the IBF Super Middleweight Champion Alejandro Berrio on October 19, 2007. Bute beat Berrio via TKO in the 11th round. With this victory, Bute became the third Romanian professional boxing world champion after Leonard Doroftei and Mihai Leu.

Taylor Alison Swift (born December 13, 1989) is an American singer-songwriter and occasional actress. Raised in Wyomissing, Pennsylvania, Swift moved to Nashville, Tennessee at the age of fourteen to pursue a career in country music. She signed to the independent label Big Machine Records and became the youngest songwriter ever hired by the Sony/ATV Music publishing house. The release of Swift's self-titled debut album in 2006 established her as a country music star. "Our Song", her third single, made her the youngest sole writer and singer of a number one song on the country chart. She received a Best New Artist nomination at the 50th Grammy Awards.

Swift's second album, Fearless, was released in late 2008. Buoyed by the chart success of the singles "Love Story" and "You Belong with Me", Fearless attracted a crossover audience and became the top-selling album of 2009. The record won four Grammy Awards, with Swift becoming the youngest ever Album of the Year winner. Fearless also received Album of the Year plaudits at the American Music Awards, Academy of Country Music Awards and Country Music Association Awards, making it the most awarded album in country music history. In 2010, Swift released her third album, Speak Now, which sold over one million copies in its first week. She then embarked on the 111-date Speak Now World Tour, which was attended by over 1.6 million fans and has become one of the highest-grossing concert tours of all time. The album's third single, "Mean", won two Grammy Awards for Best Country Song and Best Country Solo Performance. Swift is currently recording her fourth studio album, due for release in the fall of 2012.