{"id":2813,"date":"2021-03-04T10:57:14","date_gmt":"2021-03-03T21:57:14","guid":{"rendered":"http:\/\/blogs.lincoln.ac.nz\/gis\/?p=2813"},"modified":"2021-03-04T10:57:14","modified_gmt":"2021-03-03T21:57:14","slug":"setting-free-the-map","status":"publish","type":"post","link":"https:\/\/blogs.lincoln.ac.nz\/gis\/setting-free-the-map\/","title":{"rendered":"Setting Free the Map"},"content":{"rendered":"

Some places make for challenging map making.\u00a0 In this post we look at one way of working with the dragonfly data to produce a (hopefully) effective map.<\/em><\/p>\n

In a previous post we looked at massaging<\/a> some spatial data from Wallis and Futuna to make them mappable.\u00a0 One of the end results of those data was a map that will go into a journal article to communicate where all the dragonflies were observed.\u00a0 We saw previously where the island group is roughly:<\/p>\n

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As we zoom in closer, we can see where they sit within the area between Fiji and Samoa:<\/p>\n

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(interestingly, this next map makes me think that the islands are split between Melanesia and Polynesia but from what I can tell,\u00a0the country is mainly thought of as\u00a0Polynesian<\/a>)<\/p>\n

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By User:Kahuroa – Outline: File:World2Hires filled mercator.svg; Map information based on Vaka Moana: Voyages of the Ancestors – the discovery and settlement of the Pacific, ed K.R. Howe, 2008, p57., Public Domain, https:\/\/commons.wikimedia.org\/w\/index.php?curid=61904861<\/em><\/span><\/p>\n

But I digress…\u00a0 The first challenge is posed as soon as I try and set up a map that shows all of the observations across both of the main island groups:<\/p>\n

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At this scale (~1:700,000) I can’t really show very much detail – most of the map is empty space and this doesn’t really work.\u00a0 So, my next option was to use two separate maps that would allow me to zoom in to each island group and show more meaningful detail.\u00a0 With Pro, we can handle this by having two map windows (Insert tab > New Map):<\/p>\n

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I’m showing them here as side by side map windows but they could just as easily be stacked.\u00a0 Two separate maps\u00a0is going to allow me to get both sets of islands on a layout with sufficient detail to see where they are.\u00a0 I’m using the exact same layer on both maps – in fact I copied it from one and pasted it into the other.\u00a0 If I wanted to, I could symbolise them differently, no problem.\u00a0 Next, I’ll add those to a Layout and see how they fit (Insert tab > New Layout with a A4 portrait chosen):<\/p>\n

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To add the maps to the layout, click the Map Frame button,\u00a0\"\"<\/a>, choose one of the existing maps, and draw a box on the layout to place it:<\/p>\n

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Not very pretty, but it’s a start.\u00a0 I’d like to adjust the extents so that no island parts are cut off.\u00a0 To do this, I can click on one of the map frames, right-click and choose Activate.\u00a0 Then I can pan and zoom the map around to suit:<\/p>\n

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When I’m finished, I click Close Activation from the Activated Map Frame tab.\u00a0 Still not very pretty but we’re getting there.\u00a0 I’m feeling the need for a locator map to give things some better spatial context, so I’ve added a third map for this.\u00a0 The scale makes it difficult to see the islands so I quickly spun up a point layer and labelled it with the island names:<\/p>\n

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This is helpful, but I think an even wider context would be useful, so another map goes on to show the wider Pacific:<\/p>\n

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Right – I think the guts of it are here – I’ll add some scale bars and a compact legend – this map will end up as a figure in a journal article so I’m not going to worry about a title and keep it as simple as possible.\u00a0 At this point, I can’t say that I’m very happy about this map…but I sent it off to my colleague, Milen, for some comments so that I could focus on something else.\u00a0 Here’s what I sent:<\/p>\n

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Okay, I do cringe about letting this loose on the world.\u00a0 It’s like an unfinished demo song that leaks out on the internet…pretty crap actually.\u00a0 Milen suggested a few things: add the island names and perhaps swap their positions so the map reflects their actual positions better.<\/p>\n

Giving it a bit of thought, I realised that the main thing I didn’t like about this was that it was in portrait orientation – maybe landscape would give me some better opportunities?\u00a0 From the layout properties I switched it over to Landscape:<\/p>\n

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And worked through it this way:<\/p>\n

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(Forgot to tell you that I added in some transects, the blue lines<\/a>, as well…sorry.)\u00a0 Some things I like about this version – the islands are similar on the page to how they are spatially in reality, but I’m not sure I like a locator map in the upper left-hand corner – this is one of the first places people will look and having it there might place too much emphasis on it; it’s a secondary element after all.\u00a0 To keep things simple, I thought I’d have just one scale bar on the map – to honour this, I had to set the scales for both island maps to be the same and then trial and error shaped the map windows til they fit well.\u00a0 I’m counting on my reader assuming that the scale bar relates to the two island maps and not the two locator maps, which each (of course) have their own, very different, scale.\u00a0 That might be what’s called an heroic assumption.\u00a0 (For that matter, I’m assuming my reader will know that north is “up”.)\u00a0 Milen\u00a0prefered\u00a0an explicit scale for each island map so I added them:<\/p>\n

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Almost there methinks, but not quite.\u00a0 In a fit of rearrangement (Ed. more like a spasm…<\/em>), the next version was pretty much the final version:<\/p>\n

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There were a few little tweaks in there that I haven’t\u00a0 mentioned but my aim here was to talk through the design problems one often faces with maps.\u00a0 I rattle on to my students about maps being just another, visual, form of communication and it pays to think hard about how effective your maps are.\u00a0 My aim was also to show that developing maps is often an iterative processes between the cartographer and the map reader.\u00a0 I wanted to ensure that it was fit for purpose and that meant running it by Milen enough times to make sure we agreed.\u00a0 We saw something similar when making a tourism map<\/a>\u00a0previously.<\/p>\n

From a design point of view, a few things I’d like to highlight:<\/p>\n