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"So long and thanks for the maps"

"So long and thanks for all the fish, I meant maps (apologies to Douglas Adams)" was the last post in my #30DayMapChallenge report...

Friday, 20 May 2022

Fun with puzzle maps

 Look what I found!

Having taken a vacation from work and social media, I found a puzzle box in my late Dad’s old office, while visiting my Mum:

The Puzzle of the Plates
Spilhaus Repeating World Maps
1985 American Geophysical Union 
Created by Athelstan  Spilhaus

Click to enlarge

Click to enlarge

It's a jigsaw puzzle with under 20 pieces, that illustrate the breakup of Pangea - more on Wikipedia - and allows continental plates to be moved around, with explanations I'll attempt to illustrate here.

The booklet explains plate tectonics that were still quite new in 1985, as well as rudiments of projection explaining Spilhaus' choice in his atlas. Then they show the layout of the resulting map:

Click to enlarge

This puzzle shows the globe's tectonic plates on an ocean-centric layout,  emphasising the plate boundaries as edges of pieces, so you can shuffle pieces around to study how they fit together before and after the breakup of the Pangea super-continent around 200 million years ago. For reference, dinosaur extinction was 66 million years ago, and onset of vertebrates and plants  450 million years ago.

Shall we play?


First you assemble the edges like in any puzzle, then you fill in the rest, et voilà!

Click to enlarge

Next you group them by plates, and see how the resulting holes illustrate the plate movements and oceans opening and closing. Here is the classic fit before the Atlantic Ocean opened:

Click to enlarge

Finally you remove the bordering blocks and move the plates around:

- move Pacific plate on the other side of the Eurasian plate:

Click to enlarge

- flip American plate atop Eurasian plate:

Click to enlarge

- or group them around Antarctic, which the Spilhaus projection is centered on:

Click to enlarge

Notice the mountain ranges seen faintly in grey  line up perfectly from S  America thru Antarctic and E. Australia:  the  backbone of another super continent called Gondwana, the reconstruction of which was the birth of plate tectonics illustrated by this atlas...

In early 80's I was co-grad student at Queen's Uni. in E. Canada with Maarten de Wit in the link above, RIP Apr. 2020, who  published its atlas a scant 3 yrs after this puzzle!
 
Note also that latitude / longitude map grids  - distorted by the map projection - match across plates, and the backdrop paper sheet edges coincide with the 0° and 180° longitudes.

 The point of this Spilhaus atlas is that it's ocean-centric, as the locus of tectonic plate boundaries is mid-oceanic for spreading centres, and border-oceanic for subduction zones. 

Wikipedia on Plate tectonics has further details.

Further info...


See Savric et al. on the Spilhaus projection in Esri mapping, and my story map on ocean topics that lend themselves to this projection.

Wikipedia on Spilhaus makes no mention of his projection, but Big Think remedies that.

Finally, Google books posts an article and a book possibly lurking in a library near you. 

Monday, 10 January 2022

"So long and thanks for the maps"

"So long and thanks for all the fish, I meant maps (apologies to Douglas Adams)" was the last post in my #30DayMapChallenge reported below, not incl. an extra one at the end. As my life situation has changed, however, this proved to be prophetic: I'm withdrawing from social media, activism and geo work until I sort my life out. It’s been a pleasure participating in mappy adventures with y’all. Ta for now.

Friday, 19 November 2021

Satellite data help for local housing issue

 The #30DayMapChallenge Day 23 challenge is "GHSL data", here is the section in the story map that will chronicle the map challenge when it's finished:

Global Human Settlement  for Northstowe controversial development NW of Cambridge UK, monitoring housing probability (GHS-BUILT-S2, 2018) and housing footprint (GHSL-ESM, 2015) against Esri 2020 Land Cover map extract with OpenStreetMap detailed base-map. Various blended overlays 'bake' the layers into a screen pattern allowing to compare and contrast past built areas vs. currently probably built against submissions. 

Tuesday, 19 October 2021

More map art

A few years ago I used Charlie Frye's online lesson Explore future climate projections to learn how to use NetCDF and map temperature regimes - it's shown below in Patterson & Savaric's Equal Earth Projection. It became the basis for carbon emissions map just updated in the last blog post.

Wednesday, 13 October 2021

Carbon emissions reloaded

[ Updates:  watch the updated bubble map video wrapping this all up at the bottom! ]

Late 2019 I wrote in A tale of two maps

LSE’s Leslie Sklair asked me recently to produce carbon emission snapshots for an upcoming book. I had already mapped CDIAC’s CO2 emissions since 1751, I updated with BP Stat. Review current data, and I created in Esri web mapping platform some dynamic counterparts to Carbon Atlas’ static maps.

 Those 2018 data were recently updated up to 2020, and further fuels listed by CDIAC were added to create this map, using Esri's improved web mapping:

Tuesday, 28 September 2021

Return East Anglia Peatlands to being carbon sinks

Community Engagement 12345678910111213, 141516171819 & 20

[ Update 4: actual Fenlanders interviewed in this fab blog post

Update 3: peatland restoration by numbers, Indonesian example

Update 2: soil degradation and climate change masterclass, TEDtalk pointers

Update: added Why we should all be obsessed with Peatlands at the end of the story map below ]

No. 20! Isn't it fitting that chronicling East Anglia challenges & opportunities w.r.t. climate emergency - risk of flooding, sea level rise,  vulnerability indices and now pandemic - uncovered the greatest opportunity yet: returning local peatlands from carbon emitters to original carbon sinks could dwarf any individual effort to mitigate CO2 emissions, currently the major driver of climate change.

Tuesday, 21 September 2021

Sea Level Rise Maps #reloaded

[ Update 2: at bottom is the comprehensive water web map that followed this...

Update 1: near the end of the story map, see how you can style your own DEM tiles ]

 East Anglia Flood Defences Final showcased in a story map the entire flooding infrastructure framework for the region, both from rising sea levels and risk of flooding, complete w flood defence infrastructure.

Online discussions in the wake of the IPCC 2021 report broadened that scope back to an original posting almost two years ago Sea level rise models show ins&outs of climate change science. Here is that update expanding to England and NW Europe, wrapping in all the lessons learned along the way. 

Monday, 13 September 2021

'Emo' vs. 'Goth' map looks

Recently updated this story map Maps like 3D Prints: Emo or goth? A map tour of special effects - adding to existing Ice Mountain hillshade style (augmented with Misting - the Emo part), a Sunrise Hack (in fact more like sunset - the Goth part) - all John Nelson's on Esri Living Atlas Terrain layers.

Monday, 30 August 2021

"Start me up" reloaded

[ Update: watch this creepy reprise by Rolling Stones & Boston Dynamics on the 40th anniversary of the Tattoo You album ]

The 25th anniversary of Win95 launch reminded me of the cringy launch party livestreamed where I was then in Calgary. What struck me was in Rolling Stones' lyrics including "you make grown men cry" in the launch party was clipped in later adverts... 

Tuesday, 10 August 2021

"With a little help from my friends", Part II

New how-to 

Part I showed how a map of DEFRA open data can help situational awareness for a West Midlands XR event. Having done a sea level rise and risk of flooding map for the Thames River valley near London last year, I redid one now with the lessons learned in the interval. The previous Sea Level Rise map from Open Data was rather onerous: I streamlined the process to simply load free & open data with only GIS styling; the resulting Build your own can be replicated on other GIS with listed data sources.