Mapping

Temporal Map

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That qgis temporal (time) map I posted earlier this morning on the blog about positive Coronavirus cases is pretty neat.

https://www.facebook.com/andybarthur/posts/10101846691562549

But they are kind of a pain to make right now as the feature is very incomplete in QGIS:

  • No print layout design tools are available for export in qgis so you have to manually screenshot and paste the legend as an image and are limited in formatting options
  • No ability to create GIF animations directly from qgis, must export multiple images and create the GIF animation in GIMP
  • The shape file you make it from must use a date format field, it can’t process strings yet
  • You can’t do a linkage on the fly but instead do the linkage manually which leads to the creation of very large Shape files or GeoPackages due to repeated shapes in the file for each time period

the mythology of Snow’s map of cholera

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Something in the water: the mythology of Snow’s map of cholera

If there are positives to take from 2020 (a big ask I know but bear with me), the spotlight has shone brightly on the use of maps, charts, and data that help us understand COVID-19. It’s quite literally been a viral moment for geography and cartography. Not that maps weren’t vital visual and analytical tools beforehand, but they have taken centre stage this year. And of course, examining the role of geography, and cartography in contemporary infectious disease epidemiology has also meant looking at the past for examples. There’s definitely been something in the water in 2020 as inevitably the story of Dr John Snow and his map of cholera showing the outbreak in Soho, London in 1854 has frequently been recounted. You may know the story. Or you may think you know the story. Let’s see.

How GPS Actually Works

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How GPS Actually Works

We already live in the future. We have handheld devices that use satellites to pinpoint our precise locations almost anywhere on the planet. But have you ever wondered just how GPS works?

GPS devices don’t actually contact satellites and transmit information to them. They only receive data from satellites – data that’s being always-transmitted. However, GPS isn’t the only way devices can determine your location.

WMS Mapping

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One thing I miss not having internet at home is not having access to web mapping services (WMS). These internet services are handy layers for mapping without downloading individual tiles for aerial photographs, hillshades or topographic maps. I particularly like WMS now that I found the Forest Service topographic WMS service and several state’s hillshades derived from 1m or 2m DEM.

They sure are handy to have access to.