Talks to Watch

Does "land area" assume a country is perfectly flat?

859K views · Aug 19, 2020 · 17:51 · 3 HN recommenders · 4 mentions · discussed 2020–2023

Matt Parker of Stand-up Maths asks whether a country's reported land area accounts for hills and mountains, working through how surface area depends on the resolution of elevation data. It follows up on a question from a viewer and work by researchers who measured it.

Why Hacker News points people here: HN recommends it in map projection and coastline threads as a fun look at how measurement choices change area figures.

“Matt Parker from Standup Maths made a great video on exactly this subject”HN comment, 2020

What Hacker News said 4

RecommendsswilliamsioSep 2020

“StandUpMaths did a great video on this recently”

Explores whether national land area accounts for elevation.

Full comment

>But then realized that the coastline paradox must also exist for 3D surfaces (TINs or DEMs or whatnot) so asking “what is the area of a surface on earth” can be a very complex question if dealing with elevation. StandUpMaths did a great video on this recently, asking whether national land area includes elevation and which nations would gain/lose the most land area if it were/weren't: this video

RecommendsjobigoudNov 2020

“Matt Parker from Standup Maths made a great video on exactly this subject”

Matt Parker on whether land area assumes flat countries.

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Matt Parker from Standup Maths made a great video on exactly this subject a few weeks ago. "Does land area assume a country is perfectly flat?" this video

in “The True Size Of Countries: Mercator projection” · view on HN
RecommendsrdlwApr 2023

“Great video on this from Matt Parker”

Area measurement depends on elevation data resolution.

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Then it becomes a coastline problem, with different answers depending on the resolution of your elevation data. Great video on this from Matt Parker (focusing on area in this case): this video

in “The longest straight line in Great Britain (without crossing a public road)” · view on HN
Cites itjobigoudAug 2021

“Cf. Stand-up Maths”

Cited for the topography and area measurement rabbit hole.

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> over every hill, dale, nook and cranny in England That would take topography into account which another rabbit hole like calculating the perimeter of Great Britain. Cf. Stand-up Maths, Does "land area" assume a country is perfectly flat? this video

in “Concrete: The most destructive material on Earth” · view on HN