In geography, the centroid of the two-dimensional shape of a region of the Earth's surface (projected radially to sea level or onto a geoid surface) is known as its geographic centre or geographical centre or (less commonly) gravitational centre. Informally, determining the centroid is often described as finding the point upon which the shape (cut from a uniform plane) would balance. This method is also sometimes described as the "gravitational method". One example of a refined approach using an azimuthal equidistant projection, also potentially incorporating an iterative process, was described by Peter A. Rogerson in 2015. The abstract says "the new method minimizes the sum of squared great circle distances from all points in the region to the center". However, as that property is also true of a centroid (of area), this aspect is effectively just different terminology for determining the centroid. In 2019, New Zealand's GNS Science also used an iterative approach (and a variety of different projections) when determining a centre position for New Zealand's Extended Continental Shelf. However, other methods have also been proposed or used to determine the centres of various countries and regions. These include: * centroid of volume (incorporating elevations into calculations), instead of the more usual centroid of area as described above. * centre point of a bounding box completely enclosing the area. While relatively easy to determine, a centre point calculated using this method will generally also vary (relative to the shape of the landmass or region) depending on the orientation of the bounding box to the area under consideration. In this sense it is not a robust method. * finding the longitude that divides the region into two equal area parts to the east and west, and then similarly the latitude that divides the region into two equal area parts to the north and south. Like the bounding box approach described above this method would not generally locate precisely the same point if the same shaped region was oriented differently. As noted in a United States Geological Survey document, "There is no generally accepted definition of geographic center, and no completely satisfactory method for determining it." In general, there is room for debate around various details such as whether or not to include islands and similarly, large bodies of water, how best to handle the curvature of the Earth (a more significant factor with larger regions) and closely related to that issue, which map projection to use. (Wikipedia).
How Are Cities Organized? Crash Course Geography #46
Today we’re going to take a closer look at cities, examine how these large complex structures are organized, and identify patterns and differences in land use around the world. We'll begin with a quick recap of Central Place Theory, then we'll show you how the Concentric Zone Model can app
From playlist Geography
Why are People Moving to Cities? Crash Course Geography #45
According to the UN, people living in urban places now outnumber those in rural areas — which is a pretty new phenomenon for many parts of the world. So today, we’re going to discuss factors that have led to this shift in populations from rural to urban residences (known as urbanization),
From playlist Geography
Toronto 4K - Skyscraper District - Driving Downtown
Morning drive around the downtown area of Toronto, the fastest growing city in North America! Video starts on Toronto's main street (Yonge Street), continues through the entertainment and waterfront districts, and passed through Toronto's Times Square (Yonge–Dundas Square). Enjoy! Toron
From playlist Location by Continent - North America - J Utah
Introduction to Cylindrical Coordinates
This video introduces cylindrical coordinates and shows how to convert between cylindrical coordinates and rectangular coordinates. http://mathispower4u.yolasite.com/
From playlist Quadric, Surfaces, Cylindrical Coordinates and Spherical Coordinates
Quickly fill in the unit circle by understanding reference angles and quadrants
👉 Learn about the unit circle. A unit circle is a circle which radius is 1 and is centered at the origin in the cartesian coordinate system. To construct the unit circle we take note of the points where the unit circle intersects the x- and the y- axis. The points of intersection are (1, 0
From playlist Trigonometric Functions and The Unit Circle
Play in a City That Is Both Urban and Wild | National Geographic
There are few places in North America where you can so easily combine the urban with the wild, outdoor adventure with cultural exploration. Québec City offers it all! Journey along with filmmakers Tahria Sheather and National Geographic Explorer Andy Maser as they experience the city gems
From playlist News | National Geographic
Ed Kashi: The Changing Face of Marseille | Nat Geo Live
Photographer Ed Kashi travels to the oldest city in France where cultures, races, and religions collide in unforseen ways. ➡ Subscribe: http://bit.ly/NatGeoSubscribe ➡ Get More Nat Geo Live: http://bit.ly/MoreNatGeoLive About Nat Geo Live (National Geographic Live): Thought-provoking pres
From playlist National Geographic Live!: Season 3
See How Termites Inspired a Building That Can Cool Itself | Decoder
How do you cool a building without air conditioning? Using an approach called biomimicry, see how architect Mick Pearce harnessed the ingenuity of termites to design a natural cooling system for the largest commercial building in Zimbabwe. ➡ Subscribe: http://bit.ly/NatGeoSubscribe #Natio
From playlist News | National Geographic
Measuring Earth's Magnetic Field
In this video the magnitude and direction of the earth's magnetic field is measured at West Lafayette, IN (40.4259 N, 86.9081 W)).
From playlist Magnetic Fields
Experience Medieval Art and Architecture in Picturesque Brugge | National Geographic
Brugge has withstood economic downturns and world wars and remains one of the best-preserved examples of a medieval European settlement. ➡ Subscribe: http://bit.ly/NatGeoSubscribe About National Geographic: National Geographic is the world's premium destination for science, exploration, a
From playlist News | National Geographic
3 Years and 6,000 Miles on a Horse | Short Film Showcase
Inspired by the lifestyle of Mongolian nomads, National Geographic adventurer Tim Cope set off on an epic journey. In three and a half years, he traveled 6,000 miles on horseback across the breadth of Genghis Khan's ancient empire—a trek that took him from Mongolia to Hungary. In this shor
From playlist Short Film Showcase | National Geographic
Saving Orangutans in Sumatra's Disappearing Rain Forests | Nat Geo Live
Orangutans play a critical role in maintaining the health of their forest ecosystem through the dispersal of seeds, giving them the name gardeners of the forest. However, their species is under severe threat. As forests are cleared to provide room for agriculture and palm oil plantations,
From playlist National Geographic Live!: Season 11
Meet Six Rescued Rhinos That Survived Poaching | Short Film Showcase
Hear the incredible recovery stories of six rhinos who were rescued from poachers in Black Bean Productions' poignant short film. Caregivers at the Hoedspruit Endangered Species Centre (HESC) in South Africa recount the trauma several of the victims endured before arriving at the facility.
From playlist Short Film Showcase | National Geographic
Has an Elephant Trampled Your Crops? Call This Hotline For Help | Short Film Showcase
Farmers in India now have help when their livelihoods are impacted by wildlife, thanks to this hotline. If crops are destroyed or livestock is killed, a call is placed and locally based field staff are dispatched to reported incident locations. They assess the extent of the damage and help
From playlist Nature & Environment | National Geographic
Swimming Eagle Rescued From Bay | National Geographic
A family spotted an injured bald eagle swimming in the Bay of Fundy off Nova Scotia, Canada and brought it to safety. ➡ Subscribe: http://bit.ly/NatGeoSubscribe About National Geographic: National Geographic is the world's premium destination for science, exploration, and adventure. Thro
From playlist News | National Geographic
Find the midpoint between two points w(–12,–7), T(–8,–4)
👉 Learn how to find the midpoint between two points. The midpoint between two points is the point halfway the line joining two given points in the coordinate plane. To find the midpoint between two points we add the x-coordinates of the two given points and divide the result by 2. This giv
From playlist Points Lines and Planes
The Great Barrier Reef May Be Dying Faster Than We Thought | National Geographic
The latest surveys spell more bad news for the Great Barrier Reef. Following a record high water surface temperature and mass bleaching event in 2016, the Australian icon may be on track for a similar event this year. Aerial and underwater footage from 2016 and 2017, shown in this video, s
From playlist News | National Geographic