The Oldest Globe

As seen on Maps Mania: the world’s oldest surviving terrestrial globe from 1492 that obivously does not yet include the Americas!

Mappy Holiday Ornaments!

Fun little mappy holiday ornaments!

• The Spiral Globe
• More Ornaments!

Five Map Projections

 

The true size of Africa

The true size of Africa (by Reuters) is well-done & here is my favorite figure:

The Correct Map

Notthing really new here, but a few nice resources:

1. The Correct World Map
2. The “correct” map
3. A cool scrolly-type story map: The true size of Africa
4. The Equal Earth Projection

TLDR? Here's the short version: It is mathematically impossible to transform the surface of a sphere on a 2D surface without distorting at-least one of these properties: 1) angles, 2) shapes, and 3) distances. These distortions are minor at large-scales (e.g. neighborhoods or cities), but considerable at small-scales (e.g. countries, continents, or wolrd). Catographic projections need to balance these distortions in-order to make the map as useful as possible for its intended purpose. Therefore, there is no such thing as a 'correct' map: every map is wrong, but there are well-established cartographic projections that are most-suitable for certain applications.

Projections & Distances

Geodesic or planar: which to use for distance analysis (by Esri) is a nice overview of the issue. Take-home message: use geodesic distances!

Maps: Projections & Distortions

Here you can make your own version of reality: Country Centered Map Projections

1. Select your projection.
2. Select your map center.
3. Make things really weird by adding a rotation or two.
4. Share as link or PNG.
5. Awesome!

A Projection Joke!

Two Maps, Same Scale!

Seen on Flowing Data: https://joshuahhh.com/projects/same-scale/

Compare Map Projections

Compare Map Projections is fun: here's the classic Gall-Peters vs. Mercator comparison.

What precision do you need?

Great simple table showing the distance represented by decimal degrees - obviously this works anywhere for latitude, but is only correct for longitude at the equator because the line of longitude conerge towards the poles.

Source: https://community.esri.com/t5/education-blog/a-set-of-activities-for-teaching-core-content-from/ba-p/1139408 (Page 30)

The Projection Playground

The Projection Playground is fun: look at the world in different projections & you can even adjust the projection parameters to make things even more complicated. Plus you can get the D3 code.

Now: what is this useful for? No idea. For me, there are three challanges related to map projections:

1. Make students realize that what (they think) the world looks like is actually just a function of the map projection / parameters.
2. Understand the implications of 1).
3. For students in my GIS courses: Be able to project GIS data (although that's become less and less important.

Latitude / Longitude

There are many ways to figure-out the latitude and longitude for locations, but this one has to be one of the simplest: https://what-two-figures.glitch.me/

A New Map Of The World

Cool, but useless: https://www.nytimes.com/2021/02/24/science/new-world-map.html

The Best Projection?

Choropleth maps (also called thematic maps) visualize data as a function of geographic areas and, as with every map, you need a projection to convert the 3D shape of the earth to the 2D shape of your screen or piece of paper. This is not really an issue when mapping a small area (say census tracts in Massachusetts), but becomes an issue when mapping at the scale of the plant.

Designing choropleth maps: What projection to choose? tries to figure-out what map projection is the best. Obviously it has to be an equal-area projection, but which one?

For me: Equal Earth or Mollweide.

The Mercator Map of the Arctic

Seen on Maps Mania: The Mercator Map of the Arctic. Nice interactive overlay - make sure you adjust the opacity!

Mercator, it's not hip to be square

Good stuff from Ken Field: Mercator, it's not hip to be square. Quote: "Simply put, Web Mercator kills thematic maps." Perfect example: 2019 Canadian election maps.

Atmosphere, Oceans, and Continents

The EarthWindMap (https://earth.nullschool.net/) is awesome, especially the ability to visualize different atmospheric levels and weather variables. Now we have KCM-earth to compare ocean and wind currents between today and the Early Cretaceous.

Mercator (again)

Mercator - It's  flat, flat world is a nice immersive story map that nicely describes and illustrates the history of this map and map projection.

So true!