[stack]

Has anybody ever made a Flat-Earth map that can bring me from A to B to C, with all angles and distances matching reality AND usable for distances upwards of 1000 km? May I pretty please see it?

I was wondering: If the FE-maps of old were correct, then how were the seafaring navigators tricked into giving up their accurate FE-maps for inaccurate SE-maps and how come no seafaring navigator has ever complained that the SE-maps give wrong distances and wrong angles?

I found this map to be pretty accurate:

https://search.yahoo.com/search/?p=maps

It is accurate to an extent. It's a Mercator projection. As in that it's 'projected', derived from a globe. In doing so, for this type of globe projection, you see some landmass distortion, e.g., Greenland appearing the size of Africa.

[iamcpc]

Perhaps you can show us the thread where we all sat down and mapped out the world.

Is this serious? There are planes, trains, cars, horses, motorcycles and the link who can navigate hundreds and thousands of square miles on this planet.

I believe, from personal experience, this can be done using a map. Please don't take my word for it. Take a road trip across America.

What tools do you believe are making this possible?

[Tom Bishop]

Perhaps you can show us the thread where we all sat down and mapped out the world.

Is this serious? There are planes, trains, cars, horses, motorcycles and the link who can navigate hundreds and thousands of square miles on this planet.

I believe, from personal experience, this can be done using a map. Please don't take my word for it. Take a road trip across America.

What tools do you believe are making this possible?

Traditional flat map making methods are making it possible. See the following article:

The Earth is Not Round! Utah, NAD83 and WebMercator Projections

The above article explains that on the inside of the spherical models such as WebMercator (the web based version of WSG 84), it takes data from a mess of smaller flat maps to present more accurate data. The flat maps are more accurate, as the author describes.

NAD83 = Flat Map Coordinate System

https://en.wikipedia.org/wiki/State_Plane_Coordinate_System

The State Plane Coordinate System (SPS or SPCS) is a set of 124 geographic zones or coordinate systems designed for specific regions of the United States. Each state contains one or more state plane zones, the boundaries of which usually follow county lines. There are 110 zones in the contiguous US, with 10 more in Alaska, 5 in Hawaii, and one for Puerto Rico and US Virgin Islands. The system is widely used for geographic data by state and local governments. Its popularity is due to at least two factors. First, it uses a simple Cartesian coordinate system to specify locations rather than a more complex spherical coordinate system (the geographic coordinate system of latitude and longitude). By using the Cartesian coordinate system's simple XY coordinates, "plane surveying" methods can be used, speeding up and simplifying calculations.

Lower down in that article:

Originally, the state plane coordinate systems were based on the North American Datum of 1927 (NAD27). Later, the more accurate North American Datum of 1983 (NAD83) became the standard (a geodetic datum is the way a coordinate system is linked to the physical Earth). More recently there has been an effort to increase the accuracy of the NAD83 datum using technology that was not available in 1983.

The government says so as well:

https://catalog.data.gov/dataset/united-states-stateplane-zones-nad83

United States Stateplane Zones - NAD83
Metadata Updated: August 11, 2016

U.S. State Plane Zones (NAD 1983) represents the State Plane Coordinate System (SPCS) Zones for the 1983 North American Datum within United States.

NAD83 is a flat coordinate system.

Web Mercator = WSG 84

The full name of Web Mercator is WGS 84 Web Mercator

https://en.m.wikipedia.org/wiki/Web_Mercator_projection

While the Web Mercator's formulas are for the spherical form of the Mercator, geographical coordinates are required to be in the WGS 84 ellipsoidal datum.

It's a web-based version of WGS 84. The WGS part is also mentioned in the Earth Not Round! article.


...

https://www.gpsworld.com/data-collection-of-wgs-84-information-or-is-it/

In the meantime, here are a few of the main differences between WGS 84 and NAD83:

The coordinate system for WGS 84 is geographic, and the NAD83 system is projected.

https://www.gpsworld.com/data-collection-of-wgs-84-information-or-is-it/

WGS84 doesn't define a projection, so it's up to the GIS software to decide which projection to use for displaying the data on the screen (unless you manually pick a projection, of course).

Take a look at the list of projections for ARCGIS software:

http://desktop.arcgis.com/en/arcmap/latest/map/projections/pdf/geographic_transformations.pdf

NAD83 is one of them. These are all flat coordinate systems for different locations around the earth. It's taking data from flat systems, because as the "Earth Not Round!" article said, it is these flat systems that are more accurate and give out more accurate figures.

If you want accurate maps, just use a version of WSG 84 such as Web Mercator.

[edby]

On the accuracy of pre-satellite navigation, I am just reading Scott's account of the 1901-2 Antarctic expedition, and comparing the coordinates he gives against Google. The expedition knew exactly where it was, all the time.

I am just at the part where they reach what they call "The Great Ice Barrier", now called the Ross Ice Shelf.

Yeah, I would like to obtain a copy of that.

Name the work please.

The Voyage of the Discovery

There is a copy online here, the map I was talking about is at p 410 here.

[inquisitive]

Tom - the souce data is the spherical earth model WGS84.

[markjo]

Perhaps you can show us the thread where we all sat down and mapped out the world.

Is this serious? There are planes, trains, cars, horses, motorcycles and the link who can navigate hundreds and thousands of square miles on this planet.

I believe, from personal experience, this can be done using a map. Please don't take my word for it. Take a road trip across America.

What tools do you believe are making this possible?

Traditional flat map making methods are making it possible. See the following article:

The Earth is Not Round! Utah, NAD83 and WebMercator Projections

The above article explains that on the inside of the spherical models such as WebMercator (the web based version of WSG 84), it takes data from a mess of smaller flat maps to present more accurate data. The flat maps are more accurate, as the author describes.

NAD83 = Flat Map Coordinate System

No, that isn't quite what that article says.

UTM NAD83 is a projected coordinate system that represents physical locations abstracted to a flat, cartesian coordinate system. The UTM NAD83 projection uses the GRS80 ellipsoid and a center-of-the-earth anchor point as its datum, both of which are slightly different than the WGS datum.

Notice the key words "projected" and "abstracted" when the author describes the NAD836 flat coordinate system's relationship to the GRS80 ellipsoid source data.

[Tom Bishop]

If you believe that the earth is round then you believe that the round earth locations have been abstracted to the flat map of NAD83. It has a simple x and y coordinate system. There is no z. It's a state plane coordinate system. References are provided above.

It says that it uses the GRS80 ellipsoid as its center-of-earth anchor point datum, likely to integrate with other systems such as WGS; not that it's a round earth map.

From https://www.e-education.psu.edu/geog862/book/export/html/1644 we read:

    Welcome to Lesson Six of this GPS course. And this time, we'll be talking about two coordinate systems. And I have a little bit of discussion concerning heights. We've touched on that a little bit. Now these coordinate systems that we're going to discuss are plane coordinate systems based upon the fiction that the earth is flat, which, of course, immediately introduces distortion. However, much of GIS work—and GPS work as well—is done based upon this presumption.

Another comment: https://www.pobonline.com/articles/86585-geodetic-surveying-made-plain

    A decade or two ago, I was the instructor for some introductory surveying courses at a community college. In the first class we would define “plane surveying” as surveying that did not take into consideration the curvature of earth, and “geodetic surveying” as that which did. That was about the only time the two categories received anywhere near equal attention. Oh, we would point out (still in that first lecture) some of the real-world evidence of a non-flat earth, such as the fact that the length of an 11.5-mile arc on the earth's surface is only five hundredths of a foot longer than its subtended chord, or that the sum of the angles in a spherical triangle on the earth’s surface having an area of 75 square miles is only one second greater than the angle sum of the same size plane triangle. (Even today I get a kick out of those dramatic tidbits. I’m sure a real geodesist would roll his or her eyes at such trivia!) But those examples were used as reasons for not focusing—no, for not mentioning—geodetic concepts for the rest of the semester. We would end the ten-minute token nod to geodetic surveying with the tongue-in-cheek remark, “Therefore, for this class, we will respect the time-honored principle handed down through the ages—that the earth is flat.” And, truth be known, that’s probably not a bad narrowing of a dauntingly broad subject.

    But more than narrowing, it was simply that few rank-and-file surveyors in private practice ever had occasion to use geodetic concepts in their daily work. Even when we dutifully enrolled in the occasional State Plane Coordinate seminar, the principles quickly faded from memory from lack of use. If a surveyor from the general population had ever even heard of the geoid and its relationship to the ellipsoid, and where mean sea level fit into the picture, hearing about it was as far it went.

Flat Maps = Standard


Here is another source that the spherical models rely on the flat maps:

https://www-group.slac.stanford.edu/met/Align/GPS/CCS83.pdf

    The State Plane Coordinate System was established to provide a means for transferring the
    geodetic positions of monumented points to plane coordinates that would permit the use of
    these monuments in plane surveying over relatively large areas without introducing
    significant error.

    A plane-rectangular coordinate system is by definition a flat surface. Geodetic positions on
    the curved surface of the earth must be “projected” to their corresponding plane coordinate
    positions. Projecting the curved surface onto a plane requires some form of deformation.
    Imagine the stretching and tearing necessary to flatten a piece of orange peel. In California
    the Lambert Conformal map projection is used to transform the geodetic positions of
    latitude and longitude into the y (Northing) and x (Easting) coordinates of the CCS83.

Again, we see read that Geodetic positions on the spherical earth model must be "projected" to their corresponding plane coordinate positions for these spherical earth models to work.

[inquisitive]

If you believe that the earth is round then you believe that the round earth locations have been abstracted to the flat map of NAD83. It has a simple x and y coordinate system. There is no z. It's a state plane coordinate system. References are provided above.

It says that it uses the GRS80 ellipsoid as its center-of-earth anchor point, likely to integrate with other systems such as WGS; not that it's a round earth map.

From https://www.e-education.psu.edu/geog862/book/export/html/1644 we read:

Welcome to Lesson Six of this GPS course. And this time, we'll be talking about two coordinate systems. And I have a little bit of discussion concerning heights. We've touched on that a little bit. Now these coordinate systems that we're going to discuss are plane coordinate systems based upon the fiction that the earth is flat, which, of course, immediately introduces distortion. However, much of GIS work—and GPS work as well—is done based upon this presumption.

Another comment: https://www.pobonline.com/articles/86585-geodetic-surveying-made-plain

A decade or two ago, I was the instructor for some introductory surveying courses at a community college. In the first class we would define “plane surveying” as surveying that did not take into consideration the curvature of earth, and “geodetic surveying” as that which did. That was about the only time the two categories received anywhere near equal attention. Oh, we would point out (still in that first lecture) some of the real-world evidence of a non-flat earth, such as the fact that the length of an 11.5-mile arc on the earth's surface is only five hundredths of a foot longer than its subtended chord, or that the sum of the angles in a spherical triangle on the earth’s surface having an area of 75 square miles is only one second greater than the angle sum of the same size plane triangle. (Even today I get a kick out of those dramatic tidbits. I’m sure a real geodesist would roll his or her eyes at such trivia!) But those examples were used as reasons for not focusing—no, for not mentioning—geodetic concepts for the rest of the semester. We would end the ten-minute token nod to geodetic surveying with the tongue-in-cheek remark, “Therefore, for this class, we will respect the time-honored principle handed down through the ages—that the earth is flat.” And, truth be known, that’s probably not a bad narrowing of a dauntingly broad subject.

But more than narrowing, it was simply that few rank-and-file surveyors in private practice ever had occasion to use geodetic concepts in their daily work. Even when we dutifully enrolled in the occasional State Plane Coordinate seminar, the principles quickly faded from memory from lack of use. If a surveyor from the general population had ever even heard of the geoid and its relationship to the ellipsoid, and where mean sea level fit into the picture, hearing about it was as far it went.

Flat Maps = Standard


Here is another source that the spherical models rely on the flat maps:

https://www-group.slac.stanford.edu/met/Align/GPS/CCS83.pdf

The State Plane Coordinate System was established to provide a means for transferring the
geodetic positions of monumented points to plane coordinates that would permit the use of
these monuments in plane surveying over relatively large areas without introducing
significant error.

A plane-rectangular coordinate system is by definition a flat surface. Geodetic positions on
the curved surface of the earth must be “projected” to their corresponding plane coordinate
positions. Projecting the curved surface onto a plane requires some form of deformation.
Imagine the stretching and tearing necessary to flatten a piece of orange peel. In California
the Lambert Conformal map projection is used to transform the geodetic positions of
latitude and longitude into the y (Northing) and x (Easting) coordinates of the CCS83.

Again, we see read that Geodetic positions on the spherical earth model must be "projected" on to their corresponding plane coordinate position for these spherical earth models to work.

Actual distances prove the round earth is the starting point.  Cartography then produces maps.

[stack]

Traditional flat map making methods are making it possible. See the following article:

The Earth is Not Round! Utah, NAD83 and WebMercator Projections

The above article explains that on the inside of the spherical models such as WebMercator (the web based version of WSG 84), it takes data from a mess of smaller flat maps to present more accurate data. The flat maps are more accurate, as the author describes.

Fact Check: False

No where in the article does it state: "it takes data from a mess of smaller flat maps to present more accurate data."

The article states this about WebMercator (the web based version of WSG 84): "In short, it uses the same WGS84 datum as the GPS system.”

World Geodetic System (WGS84)
"The Global Positioning System uses the World Geodetic System (WGS84) as its reference coordinate system. It comprises of a reference ellipsoid, a standard coordinate system, altitude data and a geoid.
Because the Earth is curved – and in GIS we deal with flat map projections – we need to accommodate both the curved and flat views of the world. Surveyors and geodesists have accurately defined locations on Earth.”

https://gisgeography.com/wgs84-world-geodetic-system/

NAD83 = Flat Map Coordinate System

Fact Check: Misleading

"The North American Datum of 1983 (NAD 83) is the most current datum being used in North America. It provides latitude and longitude and some height information using the reference ellipsoid GRS80.”

NAD83 is derived from an ellipsoid earth model, not a flat earth model.

https://en.wikipedia.org/wiki/State_Plane_Coordinate_System

The State Plane Coordinate System (SPS or SPCS) is a set of 124 geographic zones or coordinate systems designed for specific regions of the United States. Each state contains one or more state plane zones, the boundaries of which usually follow county lines. There are 110 zones in the contiguous US, with 10 more in Alaska, 5 in Hawaii, and one for Puerto Rico and US Virgin Islands. The system is widely used for geographic data by state and local governments. Its popularity is due to at least two factors. First, it uses a simple Cartesian coordinate system to specify locations rather than a more complex spherical coordinate system (the geographic coordinate system of latitude and longitude). By using the Cartesian coordinate system's simple XY coordinates, "plane surveying" methods can be used, speeding up and simplifying calculations.

Fact Check: Misleading

You left off the last two sentences from the paragraph:

"Second, the system is highly accurate within each zone (error less than 1:10,000). Outside a specific state plane zone accuracy rapidly declines, thus the system is not useful for regional or national mapping."

NAD83 is a flat coordinate system.

Fact Check: Misleading

It is a datum based upon an ellipsoid earth model, not a flat earth model.

Web Mercator = WSG 84

The full name of Web Mercator is WGS 84 Web Mercator

https://en.m.wikipedia.org/wiki/Web_Mercator_projection

While the Web Mercator's formulas are for the spherical form of the Mercator, geographical coordinates are required to be in the WGS 84 ellipsoidal datum.

It's a web-based version of WGS 84. The WGS part is also mentioned in the Earth Not Round! article.

Fact Check: True

Web Mercator & WGS 84 are based on a spherical earth.

NAD83 is one of them. These are all flat coordinate systems for different locations around the earth. It's taking data from flat systems, because as the "Earth Not Round!" article said, it is these flat systems that are more accurate and give out more accurate figures.

Fact Check: False

As shown above, it is not taking data “from flat systems”, it is taking data from, among other things, a spherical (ellipsoid) earth model, not from a flat earth model.

[Tom Bishop]

Nope. It says right here:

https://www-group.slac.stanford.edu/met/Align/GPS/CCS83.pdf

    The State Plane Coordinate System was established to provide a means for transferring the
    geodetic positions of monumented points to plane coordinates that would permit the use of
    these monuments in plane surveying over relatively large areas without introducing
    significant error.

    A plane-rectangular coordinate system is by definition a flat surface. Geodetic positions on
    the curved surface of the earth must be “projected” to their corresponding plane coordinate
    positions. Projecting the curved surface onto a plane requires some form of deformation.
    Imagine the stretching and tearing necessary to flatten a piece of orange peel. In California
    the Lambert Conformal map projection is used to transform the geodetic positions of
    latitude and longitude into the y (Northing) and x (Easting) coordinates of the CCS83.

The State Plane Coordinate Systems are flat surfaces.

The Geodetic positions on the spherical earth model must be projected to their corresponding plane coordinate positions for these spherical earth models to work.

[inquisitive]

Nope. It says right here:

https://www-group.slac.stanford.edu/met/Align/GPS/CCS83.pdf

    The State Plane Coordinate System was established to provide a means for transferring the
    geodetic positions of monumented points to plane coordinates that would permit the use of
    these monuments in plane surveying over relatively large areas without introducing
    significant error.

    A plane-rectangular coordinate system is by definition a flat surface. Geodetic positions on
    the curved surface of the earth must be “projected” to their corresponding plane coordinate
    positions. Projecting the curved surface onto a plane requires some form of deformation.
    Imagine the stretching and tearing necessary to flatten a piece of orange peel. In California
    the Lambert Conformal map projection is used to transform the geodetic positions of
    latitude and longitude into the y (Northing) and x (Easting) coordinates of the CCS83.

The State Plane Coordinate Systems are flat surfaces.

The Geodetic positions on the spherical earth model must be projected to their corresponding plane coordinate positions for these spherical earth models to work.

The spherical earth model is reality.

[stack]

Nope. It says right here:

https://www-group.slac.stanford.edu/met/Align/GPS/CCS83.pdf

    The State Plane Coordinate System was established to provide a means for transferring the
    geodetic positions of monumented points to plane coordinates that would permit the use of
    these monuments in plane surveying over relatively large areas without introducing
    significant error.

    A plane-rectangular coordinate system is by definition a flat surface. Geodetic positions on
    the curved surface of the earth must be “projected” to their corresponding plane coordinate
    positions. Projecting the curved surface onto a plane requires some form of deformation.
    Imagine the stretching and tearing necessary to flatten a piece of orange peel. In California
    the Lambert Conformal map projection is used to transform the geodetic positions of
    latitude and longitude into the y (Northing) and x (Easting) coordinates of the CCS83.

The State Plane Coordinate Systems are flat surfaces.

The Geodetic positions on the spherical earth model must be projected to their corresponding plane coordinate positions for these spherical earth models to work.

Untrue. "Geodetic positions on the curved surface of the earth must be “projected” to their corresponding plane coordinate positions."

It says nothing like, "in doing it makes these these spherical earth models work."

It's not working in reverse. Simply, a spherical model/datum is used then projected on to a flat map.

[totallackey]

On the accuracy of pre-satellite navigation, I am just reading Scott's account of the 1901-2 Antarctic expedition, and comparing the coordinates he gives against Google. The expedition knew exactly where it was, all the time.

I am just at the part where they reach what they call "The Great Ice Barrier", now called the Ross Ice Shelf.

Yeah, I would like to obtain a copy of that.

Name the work please.

The Voyage of the Discovery

There is a copy online here, the map I was talking about is at p 410 here.

And your reading allows you to extrapolate what you provide here as substantive evidence of a continent?

Funny, the chart does not show a continent. It shows a portion of what could be anything as far as anyone is concerned.

[Tom Bishop]

Nope. It says right here:

https://www-group.slac.stanford.edu/met/Align/GPS/CCS83.pdf

    The State Plane Coordinate System was established to provide a means for transferring the
    geodetic positions of monumented points to plane coordinates that would permit the use of
    these monuments in plane surveying over relatively large areas without introducing
    significant error.

    A plane-rectangular coordinate system is by definition a flat surface. Geodetic positions on
    the curved surface of the earth must be “projected” to their corresponding plane coordinate
    positions. Projecting the curved surface onto a plane requires some form of deformation.
    Imagine the stretching and tearing necessary to flatten a piece of orange peel. In California
    the Lambert Conformal map projection is used to transform the geodetic positions of
    latitude and longitude into the y (Northing) and x (Easting) coordinates of the CCS83.

The State Plane Coordinate Systems are flat surfaces.

The Geodetic positions on the spherical earth model must be projected to their corresponding plane coordinate positions for these spherical earth models to work.

Untrue. "Geodetic positions on the curved surface of the earth must be “projected” to their corresponding plane coordinate positions."

It says nothing like, "in doing it makes these these spherical earth models work."

It's not working in reverse. Simply, a spherical model/datum is used then projected on to a flat map.

I believe the language has been very clear. See the following:

http://wvgis.wvu.edu/data/otherdocs/standardsandpubs/wv_coordinate_systems_jan02.html

Geographic Coordinate System (GCS): An unprojected coordinate system that uses latitude and longitude to define the locations of points on a sphere or spheroid. The use of longitude and latitude is encouraged for general reference and distribution of national framework data because it provides a seamless coordinate system for most of the United States. Geographic coordinates can be readily projected onto a planar coordinate system to display data properly or measure distances accurately. The Geographic Coordinate System is the recommended coordinate system for unprojected GIS data sets that cover the entire geographic extent of West Virginia.

...

State Plane Coordinate System (SPCS): A projected coordinate system used in the United State that divides each state into one or more zones to minimize distortion and to maintain accuracy of one part in 10,000. West Virginia State Plane, also known as the West Virginia Coordinate System of 1983 (referenced to NAD 1983 Datum), is based on the Lambert Conformal Conic projection. West Virginia State Plane is divided into two zones, the North Zone and South Zone. Section 30-13A-17, paragraph c of the West Virginia State Code http://wvgis.wvu.edu/otherdocs/standardsandpubs/spcs_wvcode.pdf states that the official unit of measure is meters, although many mapping professionals and surveyors still prefer U.S. Survey Feet. State Plane is utilized for large-scale mapping projects and is a popular projected coordinate system among county governments and land surveyors.

Please explain for us why a spherical model being projected onto a planar coordinate system would display data properly or measure distances accurately.

According to "common knowledge" the opposite should be true.

[markjo]

I believe the language has been very clear. See the following:

http://wvgis.wvu.edu/data/otherdocs/standardsandpubs/wv_coordinate_systems_jan02.html

Geographic Coordinate System (GCS): An unprojected coordinate system that uses latitude and longitude to define the locations of points on a sphere or spheroid. The use of longitude and latitude is encouraged for general reference and distribution of national framework data because it provides a seamless coordinate system for most of the United States. Geographic coordinates can be readily projected onto a planar coordinate system to display data properly or measure distances accurately. The Geographic Coordinate System is the recommended coordinate system for unprojected GIS data sets that cover the entire geographic extent of West Virginia.

...

State Plane Coordinate System (SPCS): A projected coordinate system used in the United State that divides each state into one or more zones to minimize distortion and to maintain accuracy of one part in 10,000. West Virginia State Plane, also known as the West Virginia Coordinate System of 1983 (referenced to NAD 1983 Datum), is based on the Lambert Conformal Conic projection. West Virginia State Plane is divided into two zones, the North Zone and South Zone. Section 30-13A-17, paragraph c of the West Virginia State Code http://wvgis.wvu.edu/otherdocs/standardsandpubs/spcs_wvcode.pdf states that the official unit of measure is meters, although many mapping professionals and surveyors still prefer U.S. Survey Feet. State Plane is utilized for large-scale mapping projects and is a popular projected coordinate system among county governments and land surveyors.

Please explain for us why a spherical model being projected onto a planar coordinate system would display data properly or measure distances accurately.

Tom, you do realize that the quote that you provided answers your own question, don't you? 

According to "common knowledge" the opposite should be true.

Common knowledge says that the smaller the zones projected, the smaller the distortions.

[Tom Bishop]

Markjo, whatever justification you want to give it, they are taking data from flat maps. I don't see how it can be successfully argued that the earth is round, but flat maps are used because they "minimize distortion".

All of this is entirely contrary to what you guys have been telling us for the last 13 years about these spherical models.

[AATW]

The Geodetic positions on the spherical earth model must be projected to their corresponding plane coordinate positions for these spherical earth models to work.

I suspect you're trolling, but if the earth is flat then why is any projection necessary?
If the earth is flat and maps are flat then all you'd need to do is scale and the map would accurately represent the earth.
Projection is needed only if the earth isn't flat.

[inquisitive]

Markjo, whatever justification you want to give it, they are taking data from flat maps. I don't see how it can be successfully argued that the earth is round, but flat maps are used because they "minimize distortion".

All of this is entirely contrary to what you guys have been telling us for the last 13 years about these spherical models.

Why do you need funding to produce a map of the world, which will be flat, when they exist according to you?

[Curious Squirrel]

Markjo, whatever justification you want to give it, they are taking data from flat maps. I don't see how it can be successfully argued that the earth is round, but flat maps are used because they "minimize distortion".

All of this is entirely contrary to what you guys have been telling us for the last 13 years about these spherical models.

Where do they state projecting it onto a flat plane 'minimizes distortion'? Was this from earlier? Your most recent one states

A projected coordinate system used in the United State that divides each state into one or more zones to minimize distortion

This is clearly noting they're using small areas so they maps created have minimal distortion from the correct spherical coordinates. There's nothing in here about the flat map minimizing distortion in comparison to using a globe, but rather that they need to use small chunks to minimize distortions when translating the source to a flat map. Once again it feels like you're reading what you want to read, not what is actually written.

[Pinky]

Markjo, whatever justification you want to give it, they are taking data from flat maps. I don't see how it can be successfully argued that the earth is round, but flat maps are used because they "minimize distortion".

All of this is entirely contrary to what you guys have been telling us for the last 13 years about these spherical models.

But how big are these flat maps? The crucial difference between flat maps and spherical maps is that for large distances, distortions emerge and they start predicting different angles and different distances.

If Earth is flat, why are these small flat maps handled individually as local maps? Why are they not stitched together into one large map?