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Winkel Tripel Projection Pros and Cons

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Winkel Tripel Projection Pros and Cons Winkel tripel projection pros and cons Continue Privacy and cookies: This site uses cookies. By continuing to use this site, you agree to use them. To learn more, including how to manage cookies, see here: Cookie Policy Who Can Determine What's Wrong With the Map Below? Earth projection from NASA's Blue Marble series. Would it help if I said that Greenland has an area of 2.166 million km2 and Africa has an area of 30.22 million km2? Suddenly, this map doesn't look very accurate. In fact, this map has been distorted, so that the mass of land farther from the equator is increased compared to those closer to the equator. All 2D rectangular maps are more or less affected by such distortions, and I'm going to talk about a few examples. The image above is produced using the Mercator projection, which is classified as a cylindrical projection. Very often cylindrical projections map the Earth on a cylinder and then effectively deploys a cylinder to give a 2D rectangle. This results in the translation of lines of equal longitude (i.e. those that measure the distance to the East or West) into parallel, vertical, equal lines. Lines of equal latitude (i.e. those that measure the distance north or south) are translated into parallel horizontal lines. However, the farther from the equator, the greater the distance between these lines. The Mercator projection can be mathematically described as $x-yambda-lambda_0 $$y 'tanh'-1' (Sin Fi) $$x and $y $2D cards, $y lambda $is longitude, $lambda_0 is considered central longitude and $Ephile is latitude. The Mercator projection was first proposed by Gerard Mercator in 1569 and has long been one of the most widely used maps. It may be because of the beauty and simplicity of the card, but ultimately its stamina was because it is conforming. For the map to be conformal, it must save angles, which means that it is ideal for navigation. Gall-Peters projection of a visible image of Earth collected by NASA. However, Mercator's projection saw its fair share of controversy. Since the Eurasian and North American continents are further from the equator than the African and South American continents, these northern continents seem larger than they actually are compared to the southern continents. In 1973, Arnaud Peters suggested that Mercator's projection was outdated because of this poor representation of the developing world. It was at this time that The Gall-Peters forecast rose to popularity. The Gall-Peters projection is known as a cylindrical projection of an equal area that uses a Mercator transformation map showing the Tissot deformation. Stefan Kuhn, CC BY-SA 3.0 $x lambda_0) cos phi_s $$y sinphi sec phi_s.$ Here $phi's$ is known as standard latitude and is taken as 44.138. The use of standard latitude ensures there are fewer distortions on the northern continents, and therefore all land parcels have areas more in line with the correct ratios than in the Mercator projection. Both of these forecasts have their pros and cons; There are forums dedicated to arguing about which projection is the best representation. But is there a less subjective way to compare distortions? Tissot's indicatrix works by imposing ideal circles on the globe and then converting these circles according to projections. A projection of Gall-Peters showing Tiso. Eric Gaba, CC BY-SA 4.0 Now this blog can last some time if necessary. There are over 50 different projection maps that have been used for certain purposes. None of them are perfect, but there are some that get it more correct than others. One of these is the Winkel Tripel projection, which is currently used as a standard projection by the National Geographic Society. The Winkel Tripel projection is known as a modified azimuth projection. An azimuth projection is a projection that retains all directions relative to this point of reference. The projection of Winkel Tripel can be described mathematically as $x frak{1}{2} left (lambda lambda_0) cosphi_1frac 2 2 phi sin fraclambda-lambda_0 {2} operatorname sinc (alpha) $y-frak{1}{2}fi-frak-sin (phi'operatorname)sinc' (alpha) $alpha arcos cos cos lambda-lambda_0'{2} and $phi'1'arccos (frac{2}'pi'$ that Winkel Tripel is neither conformal not saving the area. Instead, it compromises between the two and is seen as a more successful representation of the Earth for this compromise. Winkel Tripel projection with Tissot in Indicatrices.Eric Gaba, CC BY-SA 4.0 Truthfully I do not remember the last time I looked at the atlas before writing this article. After all, in the age of satellite images and Google Maps, atlases are really required? I don't know, but it's clear that the maps we grew up on are far from the full story. The new Advanced World map on MapChart allows you to select from nine different projections to create a map. Switch between map projections on the new Advanced World page. It's a really useful feature (among other available) that can completely change the design and feel of your card. In this post, we quickly move on to what the map projection is, how to categorize different projection maps, and the pros and cons of some of the most popular ones, including those that are available on MapChart.What is the projection map? The surface of the earth is curved, but the maps are flat. A map projection is the method by which we translate a sphere or globe into a two-dimensional view. From the globe to the map. In fact, the term map projection comes from the concept of light source across the Earth's surface to a two-dimensional surface (map). Map projections essentially represent a three-dimensional world as a flat surface, usually a screen or paper. Types of map projections based on surfaceMap projections are created using mathematical formulas. In the process, we use the surface to wrap around the Earth and project latitudes and longitudes onto the corresponding geographic coordinates on the map. There are three main types of surfaces on which you can project a map: a plane, a cone, and a cylinder. Surfaces can be stacked flat and present the Earth's surface as a map. Each of these types provides accuracy for some functions, distorting others. If we use a flat plane to build the Earth's surface, we get azimuth projections that are more accurate for polar regions. Atziumtal uniform projection. If we put a cone on Earth and untie it, it leads to conical projection. These forecasts are best to comb the regions of the Far East and the West, as distortions are constant along the general parallels. Lambert's conical conformation projection. Finally, the cylinder wrapped around the Earth so that it touches the equator will produce a cylindrical projection. The result is usually more accurate around the equator. Miller's cylindrical projection. Used on the Map of the Simple World. Variations in 3 main categories produce even more types, such as pseudo-cylindrical, modified azimuths, pseudo-coniki, hybrids, etc. Types of map projections by preserved properties (area, shape, direction, distance) - a trade between distortion, accuracy and aesthetics. Some map projections support areas, while others retain local shapes, distances, and directions. However, no projection can retain all the attributes. Depending on what metric property the projection retains, we can categorize them as follows: Conformal: preserving local topography, that is. the shape of the objects. Examples include Mercator, Lambert Conformal Conic.Equal-area: the preservation of the measure area, basically distorting the form in order to do so. Some examples are Eckert IV, Sinusoidal and Mollweid predictions. Equal: keeping the distance between the two points. An example is the projection of the plate carre.Compromise: they provide a representation of the ground, which is not quite correct in any way, but not heavily distorted in any way either. Famous ones are Winkel Tripel, Miller Cylind, Robinson, van der Grinten, etc. Typically, compromise predictions should be your choice for maps around the world like the ones you can create on MapChart. They benefit from getting close enough to real proportions and shapes, and to be Map Predictions on MapChart there are thousands of cartographic predictions that exist today. Let's take a look at some of the most popular ones that are also on MapChart.For below map predictions, we'll list some of their main characteristics as well as their pros and cons. In the end, we'll provide a few suggestions on how to choose the correct map projection. It can be helpful to have an Advanced World map open at the same time on MapChart, where you can see all these projections in action and quickly switch between them to get a better picture.1. Winkel TripelClassification: compromise, modified azimutal. Winkel Tripel has a nice balance of shape and distortion of scale. It has been used by the National Geographic Society since 1998 for general maps of the world. Eckert IVClassification: equal area, pseudo-cylindrical. Eckert IV has a good rounded shape and smooth corners. It is mainly used for thematic and other maps of the world that require exact areas. Miller cylinicalClassification: compromise, cylindrical.Miller is a modification of the Mercator projection so they are almost identical near the equator. The distortion is still serious at the poles. Also used on a simple world map page.4. Gall StereographicClassification: compromise, cylindrical. Gall resembles projections of Mercator and Miller, but has less distortion of scale and area near the poles. It is used mainly for world maps in British atlases and some other atlases5.
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