This is a list of deserts in the world by area. It includes all deserts with an area greater than 50,000 square kilometres (19,300 sq mi).

Some of the Earth's biggest deserts

The List[link]

Rank	Name	Type	Image	Area (km²)	Area (sq mi)	Location
1	Antarctic Desert	Polar	Error creating thumbnail: Invalid thumbnail parameters or image file with more than 12.5 million pixels	13,800,000 13,829,430[1]	05,340,000 5,339,573	Antarctica
2	Arctic	Polar		13,700,000 13,726,937[2]	5,300,000	Alaska (United States), Canada, Finland, Greenland (Denmark), Iceland, Norway, Russia and Sweden
3	Sahara	Subtropical	Error creating thumbnail: Invalid thumbnail parameters or image file with more than 12.5 million pixels	09,100,000 9,100,000+[3]	03,320,000 3,320,000+	Algeria, Chad, Egypt, Eritrea, Libya, Mali, Mauritania, Morocco, Niger, Sudan, Tunisia and Western Sahara
4	Arabian Desert	Subtropical		02,331,000 2,330,000[4]	00,900,000 900,000	Saudi Arabia, Jordan, Iraq, Kuwait, Qatar, United Arab Emirates, Oman and Yemen
5	Gobi Desert	Cold Winter		01,300,000 1,300,000[3]	00,500,000 500,000	Mongolia and China
6	Kalahari Desert	Subtropical		00,900,000 900,000[5]	00,360,000 360,000	Angola, Botswana, Namibia and South Africa
7	Patagonian Desert	Cold Winter	File:Patagonian.png	00,673,000 670,000[3]	00,260,000 260,000	Argentina and Chile
8	Great Victoria Desert	Subtropical		00,647,000 647,000[2]	00,250,000 250,000	Australia
9	Syrian Desert	Subtropical		00,520,000 520,000[2]	00,200,000 200,000	Syria, Jordan and Iraq
10	Great Basin Desert	Cold Winter		00,492,000 492,000[2]	00,190,000 190,000	United States
11	Chihuahuan Desert	Subtropical		00,450,000 450,000[2]	00,175,000 175,000	Mexico and United States
12	Great Sandy Desert	Subtropical		00,400,000 400,000[2]	00,150,000 150,000	Australia
13	Karakum Desert	Cold Winter		00,350,000 350,000[2]	00,135,000 135,000	Turkmenistan
14	Colorado Plateau	Cold Winter	Error creating thumbnail: Invalid thumbnail parameters or image file with more than 12.5 million pixels	00,337,000 337,000[2]	00,130,000 130,000	United States
15	Sonoran Desert	Subtropical		00,310,000 310,000[2]	00,120,000 120,000	Mexico and United States
16	Kyzyl Kum	Cold Winter		00,300,000 300,000[2]	00,115,000 115,000	Kazakhstan, Turkmenistan and Uzbekistan
17	Taklamakan Desert	Cold Winter		00,270,000 270,000[3]	00,105,000 105,000	China
18	Thar Desert	Subtropical		00,200,000 200,000[6]	00,077,000 77,000	India and Pakistan
19	Gibson Desert	Subtropical		00,155,000 156,000[7]	00,060,000 60,000	Australia
20	Simpson Desert	Subtropical		00,145,000 145,000[2]	00,056,000 56,000	Australia
21	Atacama Desert	Cool Coastal		00,140,000 140,000[2]	00,054,000 54,000	Chile and Peru
22	Mojave Desert	Subtropical		00,124,000 124,000[8][9]	00,048,000 48,000	United States
23	Namib Desert	Cool Coastal	Error creating thumbnail: Invalid thumbnail parameters or image file with more than 12.5 million pixels	00,081,000 81,000[2]	00,031,000 31,000	Angola and Namibia
24	Dasht-e Kavir	Cold Winter	100px	00,077,000 77,000[10]	00,030,000 30,000	Iran
25	Dasht-e Lut	Cold Winter		00,052,000 52,000[10]	00,020,000 20,000	Iran

See also[link]

• List of deserts

References[link]

1. ^ Ward, Paul (2001). Antarctica Fact File/
2. ^ ^{a b c d e f g h i j k l m} "Largest Desert in the World". http://geology.com/records/largest-desert.shtml. Retrieved 2011-12-27. 
3. ^ ^{a b c d} "Planet Earth - Basic Facts and Extremes". http://www.1world2travel.com/print.php?articleID=2830. Retrieved 2007-10-06. ^{[dead link]}
4. ^ "Arabian Desert". http://www.britannica.com/eb/article-9110527/Arabian-Desert. Retrieved 2007-12-28. 
5. ^ {{cite web|url=http://www.press.uchicago.edu/Misc/Chicago/9780226471549_blad.pdf%7Ctitle=Nature's Great Events:The Okavango Delta, Kalahari Desert|last=Bass|first=Karen|work=press.uchicago.edu|publisher=University of Chicago Press|date=2009-02-01|accessdate=2012-04-26}
6. ^ Thar Desert - Britannica Online Encyclopedia
7. ^ "Interesting facts about Western Australia". landgate.wa.gov.au. Western Australian Land Information Authority. http://www.landgate.wa.gov.au/corporate.nsf/web/Interesting+Facts+About+Western+Australia. Retrieved 2012-04-26. 
8. ^ "Mapping Perennial Vegetation Cover in the Mojave Desert". pubs.usgs.gov. USGS Western Geographic Science Center. 2011-06-01. http://pubs.usgs.gov/fs/2011/3077/fs2011-3077.pdf. Retrieved 2012-04-08. 
9. ^ "Recoverability and Vulnerability of Desert Ecosystems". http://mojave.usgs.gov/. USGS. 2006-03-03. http://mojave.usgs.gov/rvde/. Retrieved 2012-04-14. 
10. ^ ^{a b} Wright, John W. (ed.); Editors and reporters of The New York Times (2006). The New York Times Almanac (2007 ed.). New York, New York: Penguin Books. p. 456. ISBN 0-14-303820-6. 

[[sq:Lista e shkretëtirave sipas sipërfaqes]

Look up list in Wiktionary, the free dictionary.

List or lists may refer to:

Enumerations[link]

• Any enumeration of a set of items
• A list of comma separated values, a common way of listing in everyday life and computing. (British usage: Comma-separated values)
• A mailing list
• An electronic mailing list
• An electoral list
• List (computing)
• Task lists, a list of tasks to be completed
• Listicle, an article in list format
• Watchlist
• Ranker

Other meanings[link]

• List (watercraft), the leaning to either port or starboard of a ship
• List, an alternative term for roll in flight dynamics
• Lists (jousting), a roped-off enclosure where medieval knights jousted
• SC Germania List, German rugby union club
• List College, an undergraduate division of the Jewish Theological Seminary of America

People[link]

• Friedrich List, German economist
• Guido von List, Austrian Armanist
• John List, murderer
• Liesbeth List, Dutch singer
• Maximilian List, SS officer and Commandant of Lager Sylt, a labour camp on Alderney
• Paul List, chess player
• Peyton List, the name of two American actresses:
  • Peyton List (actress born 1986), American actress in the TV series Mad Men
  • Peyton List (actress born 1998), American actress in the Disney Channel TV series Jessie
• Siegmund Wilhelm List, WWII German field marshal

Places[link]

• List, Schleswig-Holstein, the northernmost village in Germany, on the island Sylt

Work titles[link]

The List may refer to:

• The List (magazine), a Scottish magazine
• The List (South Park), an episode of the television show South Park
• The List (The X-Files), an episode of the television show The X-Files
• The List (2007 film), a film based on the novel by Robert Whitlow
• The List (album), an album by Rosanne Cash

See also[link]

• Liszt (surname)
• Listing (disambiguation)

This disambiguation page lists articles associated with the same title. If an internal link led you here, you may wish to change the link to point directly to the intended article.

The combined area of these three shapes is between 15 and 16 squares.

Area is a quantity that expresses the extent of a two-dimensional surface or shape in the plane. Area can be understood as the amount of material with a given thickness that would be necessary to fashion a model of the shape, or the amount of paint necessary to cover the surface with a single coat. It is the two-dimensional analog of the length of a curve (a one-dimensional concept) or the volume of a solid (a three-dimensional concept).

The area of a shape can be measured by comparing the shape to squares of a fixed size. In the International System of Units (SI), the standard unit of area is the square metre (m²), which is the area of a square whose sides are one metre long.^[1] A shape with an area of three square metres would have the same area as three such squares. In mathematics, the unit square is defined to have area one, and the area of any other shape or surface is a dimensionless real number.

There are several well-known formulas for the areas of simple shapes such as triangles, rectangles, and circles. Using these formulas, the area of any polygon can be found by dividing the polygon into triangles.^[2] For shapes with curved boundary, calculus is usually required to compute the area. Indeed, the problem of determining the area of plane figures was a major motivation for the historical development of calculus.^[3]

For a solid shape such as a sphere, cone, or cylinder, the area of its boundary surface is called the surface area. Formulas for the surface areas of simple shapes were computed by the ancient Greeks, but computing the surface area of a more complicated shape usually requires multivariable calculus.

Area plays an important role in modern mathematics. In addition to its obvious importance in geometry and calculus, area is related to the definition of determinants in linear algebra, and is a basic property of surfaces in differential geometry.^[4] In analysis, the area of a subset of the plane is defined using Lebesgue measure,^[5] though not every subset is measurable. In general, area in higher mathematics is seen as a special case of volume for two-dimensional regions.

Formal definition[link]

An approach to defining what is meant by area is through axioms. For example, we may define area as a function a from a collection M of special kind of plane figures (termed measurable sets) to the set of real numbers which satisfies the following properties:

• For all S in M, a(S) ≥ 0.
• If S and T are in M then so are S ∪ T and S ∩ T, and also a(S∪T) = a(S) + a(T) − a(S∩T).
• If S and T are in M with S ⊆ T then T − S is in M and a(T−S) = a(T) − a(S).
• If a set S is in M and S is congruent to T then T is also in M and a(S) = a(T).
• Every rectangle R is in M. If the rectangle has length h and breadth k then a(R) = hk.
• Let Q be a set enclosed between two step regions S and T. A step region is formed from a finite union of adjacent rectangles resting on a common base, i.e. S ⊆ Q ⊆ T. If there is a unique number c such that a(S) ≤ c ≤ a(T) for all such step regions S and T, then a(Q) = c.

It can be proved that such an area function actually exists. (See, for example, Elementary Geometry from an Advanced Standpoint by Edwin Moise.)

Units[link]

A square metre quadrat made of PVC pipe.

Every unit of length has a corresponding unit of area, namely the area of a square with the given side length. Thus areas can be measure in square metres (m²), square centimetres (cm²), square millimetres (mm²), square kilometres (km²), square feet (ft²), square yards (yd²), square miles (mi²), and so forth. Algebraically, these units can be thought of as the squares of the corresponding length units.

The SI unit of area is the square metre, which is considered an SI derived unit.

Conversions[link]

Although there are 10 mm in 1 cm, there are 100 mm² in 1 cm².

The conversion between two square units is the square of the conversion between the corresponding length units. For example, since

1 foot = 12 inches,

the relationship between square feet and square inches is

1 square foot = 144 square inches,

where 144 = 12² = 12 × 12. Similarly:

• 1 square kilometer = 1,000,000 square meters
• 1 square meter = 10,000 square centimetres = 1,000,000 square millimetres
• 1 square centimetre = 100 square millimetres
• 1 square yard = 9 square feet
• 1 square mile = 3,097,600 square yards = 27,878,400 square feet

In addition,

• 1 square inch = 6.4516 square centimetres
• 1 square foot = 0.09290304 square metres
• 1 square yard = 0.83612736 square metres
• 1 square mile = 2.589988110336 square kilometres

Other units[link]

There are several other common units for area. The are was the original unit of area in the metric system, with

• 1 are = 100 square metres

Though the are has fallen out of use, the hectare is still commonly used to measure land:

• 1 hectare = 100 ares = 10,000 square metres = 0.01 square kilometres

Other uncommon metric units of area include the tetrad, the hectad, and the myriad.

The acre is also commonly used to measure land areas, where

• 1 acre = 4,840 square yards = 43,560 square feet.

An acre is approximately 40% of a hectare.

On the atomic scale, area is measured in units of barns, such that,

• 1 barn = 10⁻²⁸ square meters.

The barn is commonly used in describing the cross sectional area of interaction in nuclear physics.

Basic area formula[link]

Rectangles[link]

The area of this rectangle is lw.

The most basic area formula is the formula for the area of a rectangle. Given a rectangle with length l and w, the formula for the area is

A = lw  (rectangle).

That is, the area of the rectangle is the length multiplied by the width. As a special case, the area of a square with side length s is given by the formula

A = s²  (square).

The formula for the area of a rectangle follows directly from the basic properties of area, and is sometimes taken as a definition or axiom. On the other hand, if geometry is developed before arithmetic, this formula can be used to define multiplication of real numbers.

Equal area figures.

Dissection formulae[link]

Most other simple formulae for area follow from the method of dissection. This involves cutting a shape into pieces, whose areas must sum to the area of the original shape.

For an example, any parallelogram can be subdivided into a trapezoid and a right triangle, as shown in figure to the left. If the triangle is moved to the other side of the trapezoid, then the resulting figure is a rectangle. It follows that the area of the parallelogram is the same as the area of the rectangle:

A = bh  (parallelogram).

Two equal triangles.

However, the same parallelogram can also be cut along a diagonal into two congruent triangles, as shown in the figure to the right. It follows that the area of each triangle is half the area of the parallelogram:

Failed to parse (Missing texvc executable; please see math/README to configure.): A = \frac{1}{2}bh

 (triangle).

Similar arguments can be used to find area formulae for the trapezoid and the rhombus, as well as more complicated polygons.

Circles[link]

A circle can be divided into sectors which rearrange to form an approximate parallelogram.

The formula for the area of a circle is based on a similar method. Given a circle of radius r, it is possible to partition the circle into sectors, as shown in the figure to the right. Each sector is approximately triangular in shape, and the sectors can be rearranged to form and approximate parallelogram. The height of this parallelogram is r, and the width is half the circumference of the circle, or πr. Thus, the total area of the circle is r × πr, or πr²:

A = πr²  (circle).

Though the dissection used in this formula is only approximate, the error becomes smaller and smaller as the circle is partitioned into more and more sectors. The limit of the areas of the approximate parallelograms is exactly πr², which is the area of the circle.

This argument is actually a simple application of the ideas of calculus. In ancient times, the method of exhaustion was used in a similar way to find the area of the circle, and this method is now recognized as a precursor to integral calculus. Using modern methods, the area of a circle can be computed using a definite integral:

Failed to parse (Missing texvc executable; please see math/README to configure.): A \;=\; \int_{-r}^r 2\sqrt{r^2 - x^2}\,dx \;=\; \pi r^2.

Surface area[link]

Archimedes showed that the surface area and volume of a sphere is exactly 2/3 of the area and volume of the surrounding cylindrical surface.

Most basic formulae for surface area can be obtained by cutting surfaces and flattening them out. For example, if the side surface of a cylinder (or any prism) is cut lengthwise, the surface can be flattened out into a rectangle. Similarly, if a cut is made along the side of a cone, the side surface can be flattened out into a sector of a circle, and the resulting area computed.

The formula for the surface area of a sphere is more difficult: because the surface of a sphere has nonzero Gaussian curvature, it cannot be flattened out. The formula for the surface area of a sphere was first obtained by Archimedes in his work On the Sphere and Cylinder. The formula is

A = 4πr²  (sphere).

where r is the radius of the sphere. As with the formula for the area of a circle, any derivation of this formula inherently uses methods similar to calculus.

List of formulae[link]

is the length of one side of the triangle.

is half the perimeter, Failed to parse (Missing texvc executable; please see math/README to configure.): a

and Failed to parse (Missing texvc executable; please see math/README to configure.): c
are the length of each side.

and Failed to parse (Missing texvc executable; please see math/README to configure.): b
are any two sides, and Failed to parse (Missing texvc executable; please see math/README to configure.): C
is the angle between them.

and Failed to parse (Missing texvc executable; please see math/README to configure.): h
are the base and altitude (measured perpendicular to the base), respectively.

is the length of one side of the square.

and Failed to parse (Missing texvc executable; please see math/README to configure.): w
are the lengths of the rectangle's sides (length and width).

and Failed to parse (Missing texvc executable; please see math/README to configure.): b
are the lengths of the two diagonals of the rhombus.

is the length of the base and Failed to parse (Missing texvc executable; please see math/README to configure.): h
is the perpendicular height.

and Failed to parse (Missing texvc executable; please see math/README to configure.): b
are the parallel sides and Failed to parse (Missing texvc executable; please see math/README to configure.): h
the distance (height) between the parallels.

is the length of one side of the hexagon.

is the length of one side of the octagon.

     is the side length and Failed to parse (Missing texvc executable; please see math/README to configure.): n
is the number of sides.

     is the perimeter and Failed to parse (Missing texvc executable; please see math/README to configure.): n
is the number of sides.

     is the radius of a circumscribed circle, Failed to parse (Missing texvc executable; please see math/README to configure.): r
is the radius of an inscribed circle, and Failed to parse (Missing texvc executable; please see math/README to configure.): n
is the number of sides.

is the apothem, or the radius of an inscribed circle in the polygon, and Failed to parse (Missing texvc executable; please see math/README to configure.): p
is the perimeter of the polygon.

is the radius and Failed to parse (Missing texvc executable; please see math/README to configure.): d
the diameter.

and Failed to parse (Missing texvc executable; please see math/README to configure.): \theta
are the radius and angle (in radians), respectively.

and Failed to parse (Missing texvc executable; please see math/README to configure.): b
are the semi-major and semi-minor axes, respectively.

and Failed to parse (Missing texvc executable; please see math/README to configure.): h
are the radius and height, respectively.

and Failed to parse (Missing texvc executable; please see math/README to configure.): h
are the radius and height, respectively.

and Failed to parse (Missing texvc executable; please see math/README to configure.): l
are the radius and slant height, respectively.

and Failed to parse (Missing texvc executable; please see math/README to configure.): l
are the radius and slant height, respectively.

and Failed to parse (Missing texvc executable; please see math/README to configure.): d
are the radius and diameter, respectively.

is the base area, Failed to parse (Missing texvc executable; please see math/README to configure.): P
is the base perimeter and Failed to parse (Missing texvc executable; please see math/README to configure.): L
is the slant height.

is the area of the square in square units.

is the area of the circle in circular units.

The above calculations show how to find the area of many common shapes.

The area of irregular polygons can be calculated using the "Surveyor's formula".^[6]

Additional formulae[link]

Areas of 2-dimensional figures[link]

• a triangle: Failed to parse (Missing texvc executable; please see math/README to configure.): \tfrac12Bh

(where B is any side, and h is the distance from the line on which B lies to the other vertex of the triangle). This formula can be used if the height h is known. If the lengths of the three sides are known then Heron's formula can be used: Failed to parse (Missing texvc executable; please see math/README to configure.): \sqrt{s(s-a)(s-b)(s-c)}
where a, b, c are the sides of the triangle, and Failed to parse (Missing texvc executable; please see math/README to configure.): s = \tfrac12(a + b + c)
is half of its perimeter. If an angle and its two included sides are given, the area is Failed to parse (Missing texvc executable; please see math/README to configure.): \tfrac12 a b \sin(C)
where C is the given angle and a and b are its included sides.  If the triangle is graphed on a coordinate plane, a matrix can be used and is simplified to the absolute value of Failed to parse (Missing texvc executable; please see math/README to configure.): \tfrac12(x_1 y_2 + x_2 y_3 + x_3 y_1 - x_2 y_1 - x_3 y_2 - x_1 y_3)

. This formula is also known as the shoelace formula and is an easy way to solve for the area of a coordinate triangle by substituting the 3 points (x₁,y₁), (x₂,y₂), and (x₃,y₃). The shoelace formula can also be used to find the areas of other polygons when their vertices are known. Another approach for a coordinate triangle is to use Infinitesimal calculus to find the area.

• a simple polygon constructed on a grid of equal-distanced points (i.e., points with integer coordinates) such that all the polygon's vertices are grid points: Failed to parse (Missing texvc executable; please see math/README to configure.): i + \frac{b}{2} - 1

, where i is the number of grid points inside the polygon and b is the number of boundary points. This result is known as Pick's theorem.

Area in calculus[link]

Integration can be thought of as measuring the area under a curve, defined by f(x), between two points (here a and b).

The area between two graphs can be evaluated by calculating the difference between the integrals of the two functions

• The area between a positive-valued curve and the horizontal axis, measured between two values a and b (b>a) on the horizontal axis, is given by the integral from a to b of the function that represents the curve.
• The area between the graphs of two functions is equal to the integral of one function, f(x), minus the integral of the other function, g(x).
• An area bounded by a function r = r(θ) expressed in polar coordinates is Failed to parse (Missing texvc executable; please see math/README to configure.): {1 \over 2} \int_0^{2\pi} r^2 \, d\theta

.

• The area enclosed by a parametric curve Failed to parse (Missing texvc executable; please see math/README to configure.): \vec u(t) = (x(t), y(t))

with endpoints Failed to parse (Missing texvc executable; please see math/README to configure.):  \vec u(t_0) = \vec u(t_1) 
is given by the line integrals

Failed to parse (Missing texvc executable; please see math/README to configure.): \oint_{t_0}^{t_1} x \dot y \, dt = - \oint_{t_0}^{t_1} y \dot x \, dt = {1 \over 2} \oint_{t_0}^{t_1} (x \dot y - y \dot x) \, dt

(see Green's theorem) or the z-component of

Failed to parse (Missing texvc executable; please see math/README to configure.): {1 \over 2} \oint_{t_0}^{t_1} \vec u \times \dot{\vec u} \, dt.

Surface area of 3-dimensional figures[link]

• cone: Failed to parse (Missing texvc executable; please see math/README to configure.): \pi r\left(r + \sqrt{r^2 + h^2}\right)

, where r is the radius of the circular base, and h is the height. That can also be rewritten as Failed to parse (Missing texvc executable; please see math/README to configure.): \pi r^2 + \pi r l

where r is the radius and l is the slant height of the cone. Failed to parse (Missing texvc executable; please see math/README to configure.): \pi r^2 
is the base area while Failed to parse (Missing texvc executable; please see math/README to configure.): \pi r l 
is the lateral surface area of the cone.

• cube: Failed to parse (Missing texvc executable; please see math/README to configure.): 6s^2

, where s is the length of an edge.

• cylinder: Failed to parse (Missing texvc executable; please see math/README to configure.): 2\pi r(r + h)

, where r is the radius of a base and h is the height. The 2Failed to parse (Missing texvc executable; please see math/README to configure.): \pi r can also be rewritten as Failed to parse (Missing texvc executable; please see math/README to configure.): \pi

d, where d is the diameter.

• prism: 2B + Ph, where B is the area of a base, P is the perimeter of a base, and h is the height of the prism.
• pyramid: Failed to parse (Missing texvc executable; please see math/README to configure.): B + \frac{PL}{2}

, where B is the area of the base, P is the perimeter of the base, and L is the length of the slant.

• rectangular prism: Failed to parse (Missing texvc executable; please see math/README to configure.): 2 (\ell w + \ell h + w h)

, where Failed to parse (Missing texvc executable; please see math/README to configure.): \ell

is the length, w is the width, and h is the height.

General formula[link]

The general formula for the surface area of the graph of a continuously differentiable function Failed to parse (Missing texvc executable; please see math/README to configure.): z=f(x,y),

where Failed to parse (Missing texvc executable; please see math/README to configure.): (x,y)\in D\subset\mathbb{R}^2
and Failed to parse (Missing texvc executable; please see math/README to configure.): D
is a region in the xy-plane with the smooth boundary:

Failed to parse (Missing texvc executable; please see math/README to configure.): A=\iint_D\sqrt{\left(\frac{\partial f}{\partial x}\right)^2+\left(\frac{\partial f}{\partial y}\right)^2+1}\,dx\,dy.

Even more general formula for the area of the graph of a parametric surface in the vector form Failed to parse (Missing texvc executable; please see math/README to configure.): \mathbf{r}=\mathbf{r}(u,v),

where Failed to parse (Missing texvc executable; please see math/README to configure.): \mathbf{r}
is a continuously differentiable vector function of Failed to parse (Missing texvc executable; please see math/README to configure.): (u,v)\in D\subset\mathbb{R}^2

Failed to parse (Missing texvc executable; please see math/README to configure.): A=\iint_D \left|\frac{\partial\mathbf{r}}{\partial u}\times\frac{\partial\mathbf{r}}{\partial v}\right|\,du\,dv.

^[4]

Minimization[link]

Given a wire contour, the surface of least area spanning ("filling") it is a minimal surface. Familiar examples include soap bubbles.

The question of the filling area of the Riemannian circle remains open.

See also[link]

• Equi-areal mapping
• Integral
• Orders of magnitude (area)—A list of areas by size.
• Perimeter
• Planimeter, an instrument for measuring small areas, e.g. on maps.
• Volume

References[link]

Notes[link]

External links[link]

Wikimedia Commons has media related to: Area

Look up area in Wiktionary, the free dictionary.

• Weisstein, Eric W., "Area" from MathWorld.
• Area Calculator
• Area formulas
• Conversion cable diameter to circle cross-sectional area and vice versa

(Clifford) Allan Redin Savory (born September 15, 1935) is a Zimbabwean biologist, farmer, soldier, exile, environmentalist and winner of the Banksia International Award 2003.^[1] and winner of the Buckminster Fuller Award 2010.^[2] He is the originator of the Holistic Management concept.

Political Involvement[link]

Savory was elected into the Rhodesian Parliament representing Matobo constituency in the 1970 election. After resigning from the Rhodesian Front in protest over its racist policies and handling of the war, Savory reformed the defunct Rhodesia Party formerly led by Sir Roy Welensky. Subsequently all moderate white parties united in opposition to Ian Smith in what was known as the National Unifying Force (NUF) led by Savory. When Savory made a public statement that if he had been born a black Rhodesian he would have been a guerilla fighter and urged white Rhodesians to understand why he would feel this, Ian Smith denounced him as a traitor. Because the NUF party would not stand by Savory he relinquished leadership to Tim Gibbs, son of Rhodesia’s last Governor. Savory continued to fight Ian Smith and his policies, in particular opposing the Internal Settlement under Bishop Abel Muzorewa. Finally faced with detention by the Smith government Savory escaped and went into self imposed exile to continue his scientific work as there was no more he felt a white Rhodesian could do to speed an end to the civil war.^[3]

Holistic Management Concept[link]

Savory had begun working on the ancient problem of land degradation (desertification) in 1955 in Northern Rhodesia where he served in the Colonial Service as Provincial Game Officer, Northern and Luapula Provinces. He subsequently continued this work in Southern Rhodesia first as a research officer in the Game Department, then subsequently as an independent scientist and international consultant. When in exile Savory worked from the Cayman Islands into the Americas introducing his new discoveries about both the cause of desertification and how to reverse it using increased numbers of livestock. This work he subsequently wrote up in the book "Holistic Management: A New Decision Making Framework" written with his wife Jody Butterfield and published by Island Press (1989; 1999 2nd edition). In 1992 he co-founded the Africa Center for Holistic Management with his wife, Jody Butterfield, and in 2009 the Savory Institute, which he currently heads. In 2010 Savory and the Africa Center for Holistic Management won The Buckminster Fuller Challenge.^[4]

Today, thousands of families, corporations and businesses are using the holistic management framework developed by Savory to radically improve the quality of their lives and regenerate the resource base that sustains them. This includes conservation projects in the U.S., Africa, Canada and Australia, where large tracts of land are being transformed as desertification is reversed through Holistic Management using livestock and holistic planned grazing as the main agent of change.[2]

See also[link]

• Savory brittleness scale
• Rhodesian general election, 1974

References[link]

Savory, Allan; Jody Butterfield (1998-12-01) [1988]. Holistic Management: A New Framework for Decision Making (2nd ed. ed.). Washington, D.C.: Island Press. ISBN 1-55963-487-1. 

1. ^ Banksia Environmental Foundation. "2003" AWARD
2. ^ Buckminster Fuller Institute
3. ^ "Bring Back the Buffalo!". The Washington Post. May 12, 1997. http://www.washingtonpost.com/wp-srv/style/longterm/books/chap1/bringbac.htm. 
4. ^ John Thackara, "Seed Magazine", June 2010, "[1]", 8-6-10

External links[link]

• Savory Institute
• Africa Centre for Holistic Management