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Put together by the David Rumsey Map Collection, this amazing composite map is a high-resolution, scrollable, zoomable map of San Francisco circa 1938. Each of the vertical photographs used in the composite map, says the collection, was shot by Harrison Ryker, an Oakdale, Calif., native who studied at the University of California–Berkeley after serving in the U.S. Army in World War I.

In his time after the war, Ryker teamed with pilots flying out of Oakland to practice his hobby in aerial photography. Over the years, Ryker opened a map publishing business and earned patents for new cartographic instruments.

“The map may look familiar to San Franciscans,” says Laughing Squid, “but there are a number of historical oddities—in 1938 vast swathes of the Sunset district were still covered in sand dunes, and sections of the aerial photos were censored to conceal military installations.”

Indeed, on a broad scale, the old composite map compares pretty well to the modern view offered by Google. But, zooming all the way in to the 1938 map offers you a new view on the history of the town.

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Photo: Christien Zenino

Climate change is changing the planet. Yes, it’s doing it in all those ways that you already know about: rising seas, rising temperatures, changing rainfall patterns, more extreme weather. But climate change is changing the planet in another dramatic way, too: It’s actually causing the entire crust of the Earth to shift. According to new research by Jianli Chen and colleagues, climate change–induced glacier melt and sea level rise have thrown the whole planet off-kilter.

The Earth is a ball that floats in space, and the Earth’s surface—the tectonic plates that make up the land—are like a shell that floats on the mantle below. Just like the hard chocolate coating can slip and slide on your soft serve ice cream, the crust of the Earth can slide over the mantle. This is different than continental drift. This is the whole surface of the planet moving as one. The rotation axis of the Earth stays steady, the land masses shift around it. The idea is known as “true polar wander,” and its occurrence is a part of the planet’s history.

The Earth is not a perfect sphere—it’s kind of fat at the middle—and changing how the mass on the surface is distributed changes how the tectonic plates sit in relation to the planet’s rotation axis. By melting Greenland and other glaciers, say the researchers, the Earth’s geographic North Pole has drifted to the east at around 2.4 inches each year since 2005. Nature:

From 1982 to 2005, the pole drifted southeast towards northern Labrador, Canada, at a rate of about 2 milliarcseconds — or roughly 6 centimetres — per year. But in 2005, the pole changed course and began galloping east towards Greenland at a rate of more than 7 milliarcseconds per year.

Seasonal shifts in how ice and water are spread around the world mean that the North Pole is always sort of wandering around. But drift triggered by climate change is new. It’s a sign that global warming isn’t just changing how we might live in the world, but the very face of the world itself.

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Dunwich beach, across which storms pulled the ancient city. Image: modagoo

In 1066, the town of Dunwich began its march into the sea. After storms swept the farmland out for twenty years, the houses and buildings went in 1328. By 1570, nearly a quarter of the town had been swallowed, and in 1919 the All Saints church disappeared over the cliff. Dunwich is often called Britain’s Atlantis, a medieval town accessible only to divers, sitting quietly at the bottom of the ocean off the British Coast.

Now, researchers have created a 3D visualization of Dunwich using acoustic imaging. David Sear, a professor at the University of Southampton, where the work was done, described the process:

Visibility under the water at Dunwich is very poor due to the muddy water. This has limited the exploration of the site. We have now dived on the site using high resolution DIDSON ™ acoustic imaging to examine the ruins on the seabed – a first use of this technology for non-wreck marine archaeology.

DIDSON technology is rather like shining a torch onto the seabed, only using sound instead of light. The data produced helps us to not only see the ruins, but also understand more about how they interact with the tidal currents and sea bed.

Using this technology gives them a good picture of what the town actually looks like. Ars Technica writes:

We can now see where the local churches stood, and crumbling walls pinpoint the ancient town’s remits. A one kilometer (0.6 mile) square stronghold stood in the center of the 1.8km2space (about 0.7 square miles), with what looks like the remains of Blackfriars Friary, three churches, and the Chapel of St Katherine standing within it. The northern region looks like the commercial hub with lots of smaller buildings largely made of wood. It’s thought that the stronghold, as well as its buildings and a possible town hall, may date back to Saxon times.

Professor Sears sees this project as not just one of historical and archaeological importance, but also as a forecast of the fate of seaside cities. “It is a sobering example of the relentless force of nature on our island coastline. It starkly demonstrates how rapidly the coast can change, even when protected by its inhabitants. Global climate change has made coastal erosion a topical issue in the 21st Century, but Dunwich demonstrates that it has happened before. The severe storms of the 13th and 14th Centuries coincided with a period of climate change, turning the warmer medieval climatic optimum into what we call the Little Ice Age.”

So, in a million years, when aliens come to look at our planet, it might look a lot like Dunwich.

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Over the past few decades Lake Urmia in Iran has steadily dried up. Photo: Google / Landsat 

Since 1972, the U.S. has flown a series of satellites known as the Landsat program, a fleet of Earth-observing satellites that were tasked with taking pictures from space. Landsat’s gorgeous photos have been a favorite of the Earth-as-art crowd, and the satellites’ observations have provided an absolutely critical long-term record of how our planet is changing.

The development of Dubai, United Arab Emirates. Photo: Landsat / Google

Today, Google put out the Earth Engine, a fascinating tool that showcases a scrollable, zoomable time-lapse of the entire planet as seen by Landsat over the decades. The Landsat photos only go back to 1984, but they show the dramatic ways in which the planet has changed in such a brief period of time. To help you get started, Google pulled out some highlights to look at, such as the drying of the Aral Sea or the deforestation of the Amazon. But the tool does show the whole planet (just the land, not the oceans), and there are many more cool things to be seen.

NASA’s Earth Observatory has a more detailed look at this, the development of the oil sands project in Alberta, Canada. Photo: Landsat / Google

But don’t bother looking for Antarctica, because it’s not included. (Sad.)

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As far as we know H7N9 cannot be passed directly from person to person. But if it could, this map shows how it could spread from the epicenter of the disease in eastern China. Photo: A. J. Tatem, Z. Huang and S. I. Hay / Nature

So far as we know, China’s deadly new strain of bird flu—H7N9, which was so far killed 22 and infected 104, all in China—can’t pass directly from person-to-person. But if it could, says Oxford University’s Jeremy Farrar to Nature, this unnerving, if speculative, map shows how it could spread.

According to the researchers, the map highlights how the area of China where H7N9 is showing up is also a hub for international air travel. “A quarter of the global population outside of China lives within two hours of an airport with a direct flight from the outbreak regions, and 70 percent if a single connecting flight is included,” they explain.

Over the past couple months, this strain of flu has spread from Shanghai, where it was first found, up to Beijing. In the past nine days, nine more deaths have been attributed to the virus. According to the World Health Organization, says CNN, H7N9 is “an unusually dangerous virus for humans.” The pool of people affected has so far remained relatively small. But there is enough unknown about the new bird virus to have scientists worried.

“So will H7N9 prove to be controllable? Will it remain entrenched in animals? Or will it, like the H1N1 virus, stably adapt to humans and cause a pandemic?” asks clinical researcher Peter Horby in an opinion story in Nature. His assessment isn’t exactly reassuring:

“The fine line between foresight and alarmism can only be drawn in retrospect. Nevertheless, my colleagues and I consider that H7N9 has many of the traits that make a new flu virus worrisome.”

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