davidkroodsma.bsky.social
Chief Scientist, Global Fishing Watch. I lead a team that uses satellites and AI to reveal all major human activity at sea. globalfishingwatch.org
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This is all vessels. And using imagery (sar or optical) up there is going to be horribly difficult because the density of vessels is low and the density of icebergs is high.
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At some point I will get around to making this for more years than just 2019.
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Yeah, that’s didn’t realize that either until I made the map. You can also see how critical those rivers in northern Russia must be for transportation—but only for half the year!
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Nice! It is great to see this.
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It has been almost three and a half years since Caldor, and given the three "mild" fire seasons since then, it's amazing how quickly I have forgotten about the risk posed by the forests behind my neighborhood. LA is reminding me.
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With South Asia (which might be more than Europe once we include vessels without AIS) being at the bottom.
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I think I like having the two areas of most intense vessel traffic -- Europe and East Asia -- on opposite sides of the map.
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And here's elastic-2 with AIS data: bsky.app/profile/tim....
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Do you have the time of day of this video?
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It is because of different regulations and also different abundances of fish!
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Here you go: bsky.app/profile/davi...
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That said, equal earth preserves area much better. But I really like the focus on the global coastline and ocean provided by elastic-2.
Also, when I say "we made the maps," I mean that @tim.hochberg.io made/found the maps and we commented on them.
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Previous map is all vessel activity from AIS-the map is most distorted in the area with the most traffic!
We looked around, and found the elastic-2 projection github.com/jkunimune/el..., which can give a similar view as Spilhaus, but doesn't distort the coastlines quite as much (except Australia).
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I like this projection not because of how it shows the ocean, but rather because it shows the global coastline as if it were a mostly-continuous line. Coastal waters are where the vast majority of human activity in the ocean is. However Spilhaus distorts the coastline a lot in some regions.
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Yeah -- I looked into this recently. There isn't a projection ready-to-go from cartopy/proj, but I did find this repo: github.com/rtlemos/spil...
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I think it depends on the context. Similarly, I often don’t like a comma in sentences that start with “Here,” but almost all academic writing uses that comma. “Here we show that…” feels so much more direct/less ponderous/less pretentious than “Here, we show that…”
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That's a good idea -- unfortunately not straightforward using cartopy and Global Fishing Watch's pyseas library. However, I can give you Stereographic:
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Yes -- because fishing regulations (and who is licensed to fish there) are different inside Exclusive Economic Zones (which extend 200 nautical miles from shore) than on the high seas, you get those "holes" in the map.
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I actually started drafts of replies with such zoomed in views, and then had to get back to responding to slack messages. They are coming soon :-)
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5) and finally, a new role on my team: Senior Scientist, Head of Research Impact. If this work excites you, and you want to lead efforts to drive impact with it, apply here: job-boards.greenhouse.io/globalfishin...
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Annual Review of Marine Science: Improving ocean management using insights from space, www.annualreviews.org/content/jour...
PNAS: Global expansion of marine protected areas and the redistribution of fishing effort, www.pnas.org/doi/10.1073/...
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4) Publications from our research network:
Science: Ship collision risk threatens whales across the world’s oceans, www.science.org/doi/10.1126/...
npj Ocean Sustainability: A global assessment of preferential access areas for small-scale fisheries, www.nature.com/articles/s44...
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3) "Ask the expert" posts with Senior Manager Hannah Linder on data pipelines (globalfishingwatch.org/insights/ask...), and Front End Engineer Jose Angel Parreño on our map visualizations (globalfishingwatch.org/insights/ask...).
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2) We highlighted updates to our R package, which allows researchers to easily pull data from our API, globalfishingwatch.github.io/gfwr/
globalfishingwatch.org/our-apis/
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Stories from the latest newsletter:
1) We supported research, published in Science, on the risk of whales to shipping vessels: globalfishingwatch.org/news-story/g...
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TL;DR:
A book I published a decade ago, The Bicycle Diaries, is good, but I had to reread it to be reminded of that. You can download a free copy here: rideforclimate.com/blog/?p=1467
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Also, this graph from the article is incredibly impressive. We live in the era of the satellite.
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A coworker showed me this post and I immediately had to make some maps with our data. There is a lot of human activity here even though there is relatively little land.
bsky.app/profile/davi...
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In the next year, we at Global Fishing Watch are going to use Planet imagery to detect vessels across almost all of the PAAs in the world, hopefully getting a better picture of small and large scale fishing activity in these PAAs. bsky.app/profile/paul...