Thursday, April 18, 2024

The Possible Collapse of Oceanic Circulation

This map, via Down to Earth shows the Atlantic Meridional Overturning Circulation (AMOC).

The AMOC is like a "heat conveyor belt". It moderates temperatures on the planet by moving warmer air to northern latitudes while returning cooler air to the tropics. It has already slowed down by about 15%, according to a 2021 study published in Nature Geoscience. This current could come to a halt sometime this century due to global warming. 

The effects of this would be pretty devastating to much of the planet. It would mean more heat in the tropics, possibly drying out the Amazon Basin, more melting of Antarctic ice and limiting monsoons in India and Africa which are relied upon for growing crops. In Europe a collapse would mean a major cooling of average temperatures. We might even see a reverse of the current migration situation where climate refugees begin moving south instead of north. For much more details, see

Wednesday, April 10, 2024

Planning for the Next Eclipse

Maybe you saw Monday's eclipse and were impressed enough to want to travel to see another one or maybe you missed it because life got in the way or you couldn't justify the time and expense of travel. Or, maybe you're like me and foolishly traveled to Rochester, New York where clouds like to gather and linger. Here is what I saw in the zone of totality,

a solid wall of clouds. Even so, the experience was worth it, watching the sky get completely dark in the middle of the day and suddenly get light again. So where will the next ones happen? Unfortunately not in the continental United States for another 20 years. However, if you want to travel or plan way ahead here are some maps for you.

From the Great American Eclipse page here are the eclipses between 2021 and 2030. From that same site you can buy the Atlas of Solar Eclipses 2020 to 2045. This book shows details for 56 eclipses woldwide with maps of each path. The cover is striking.

While on the subject of atlases, the cover of the Atlas of Central Solar Eclipses in the USA shows eclipses out to 2099, if you plan on living that long.

At a recent talk at the University of California, Berkeley Library this map was shown. I would love to se a more readable version. 

A recent article in Time shows somewhat detailed paths for eclipses up to 2067. They're just Google map screen shots with lines so you will need a more detailed map for trip planning. Here is an example of the 2034 eclipse that will traverse Africa and parts of Asia.
Finally, if you really want a deep dive EclipseWise is your source for details of every future and past eclipse, everywhere. Here is their map of the 2021-2030 decade.

Wednesday, April 3, 2024

If Mars Were on Earth

This image of the surface of Mars was released last Spring as part of the Atlas of Mars. Images were compiled from the Emirates Mars Mission "Hope", an approximately two year mission in that began orbiting the planet in 2021.

via New York Times
 Some remarkably detailed images and maps have been created, including this one showing topography.

via New York Times

A zoom in on this shows that there are lines of latitude and longitude.

From the above image you can see that Olympus Mons, the highest point on Mars is located at around 18 degrees north. This got me thinking about where these features would be placed on Earth so I projected the map.

The first version of this map was better but my computer mangled it. This recovered image is a bit warped but you get the general idea. The large volcanic mountains hover in the Pacific Ocean off the coast of Mexico. The other most prominent feature, the Hellas Planitia, a giant impact crater would be just north of Antarctica. 

Keep in mind the longitude is an artificial construct. Latitude is based on a planet's center of rotation but longitude starts where a society chooses it to start. On Earth, a bias towards England has won the day. On Mars someone made a decision about the center of longitude (I have not been able to find out how that was determined yet) and there it is. In other words Olympus Mons could be anywhere on the 18 degree north latitude. Puebla, south of Mexico City, near San Juan, Puerto Rico, in the Sahara Desert or southern India.

I tried a similar and maybe more successful approach with the first image here. I could not find what projection was used so I just projected it onto a world map with a Mollweide projection, which seems close to what was used.

I manipulated the image after the fact to make the countries white instead of black. This created an unintentional yarn-like effect that I really like,

reminding me of this 30 Day Map Challenge Map I made in 2022.

This projection had the effect of moving all the features closer together so that the big volcanoes are further east, closer to the coast of Mexico, 

while the Hellas Planitia is further west, closer to Madagascar.

Useless exercise? Maybe, but it was fun to work on and somewhat informative.

Wednesday, March 27, 2024

Tacografical Maps

International Taco Day is coming up on Sunday, March 31st - not to be confused with National Taco Day in October. Here are a few maps to enjoy your tacos by. This one I've seen in several taquerias. It took a long time to find a version that is readable online (you may need to click on it to see it at a readable scale) but I finally Reddit came through for me.

 Expedia Mexico has another take on Tacography.

Here yet another Tacographic map found on Pinterest Japan.

Finally there is the Tacopedia, an encyclopedia of Mexican taco culture.


Wednesday, March 20, 2024

Endangered Languages of New York City

 In January I did a series of posts on endangered languages. A few weeks ago the New York Times had an excellent "scrollytelling" graphic story on these languages and where they are spoken within New York City.

as you scroll down the page languages appear down Manhattan island.

Some quotes from the text: "Most people think of endangered languages as far-flung or exotic, the opposite of cosmopolitan" and "of the 700 or so speakers of Seke, most of whom can be founds in a cluster of villages in Nepal, more than 150 have lived in or around two apartment buildings in Brooklyn." According to linguist Ross Perlin there are more endangered languages in and around New York City than there than "have ever existed anywhere else."

There are profiles of speakers of these languages with a speaker button you can click to hear them speak.

A few neighborhoods are highlighted including the part of the South Bronx where my father grew up.

Continued scrolling reveals some of the languages in very specific places,

so I can see that there are Balanta-Ganja speakers (from Guinea-Bissau and the Gambia in West Africa) right around the corner from my grandmother's apartment building.

Much of the geographic content in this article is from the New York City Language Map, another great resource and rabbit hole to disappear down.

For much more see the  Times story online and the nyc language map.

Wednesday, March 13, 2024

Nice Eclipse Maps - Part 2

As promised from last week's post here are a couple additional sites that nicely visualize the path of next month's eclipse. The first one is from Bloomberg, How to Find the Best Cities to Watch the Eclipse. One of the best things about this page is that it starts with an animated map tracing the path and degree of size of the moon's shadow at various locations during the course of the eclipse's time frame. Here is a still frame from 3:10 PM Eastern time.

This is followed by a map showing the increases in searches for travel to cities in the path of totality. Little Rock has the largest increase in the United States but Mazatlan was even more popular.

Next, there is a dropdown where you can choose from a number of cities to see how much the sun will be obscured along with a time lapse animation,

 and a map showing your city's place in the bands of obscuration.

as well as a map of average cloudiness, though the color scheme is a bit difficult to understand.

Finally there's the National Eclipse site with maps for each state (just Google Maps with lines) 

and lists of all major towns within the zone of totality. This one shows the start times of totality and is color coded by time zone. 

via National Eclipse
At the end is one showing the percentage of obscuration for those unfortunate cities outside the zone of totality.
via National Eclipse

Wednesday, March 6, 2024

A Few Nice Eclipse Maps-Part 1

In a month a total eclipse will make its way across North America. On April 8th the path will travel quickly, (under two hours) from Mazatl├ín on Mexico's Pacific coast to Newfoundland, Canada and then into the Atlantic Ocean. There are some really nice visualizations of the eclipse's path. I'll show two today and more next week. The first one I saw at the last fall's NACIS Conference in Pittsburgh. 

This visualization by Michala Garrison at NASA, shows both next month's total eclipse and the annular eclipse (where the moon was further from Earth and therefore didn't completely obscure the sun) that occurred on October 14, 2023, right after the conference's end. Garrison spoke at NACIS about how she created this map and you can watch it here. Here is a close up of where the two eclipse paths would intersect (if they were simultaneous) near San Antonio, Texas.

The ovals represent the moon's umbra. If you look closely you can see how she incorporated the city lights visualization. This helps see the urban areas and is also appropriate because it will be dark in along the path for up to a few minutes.

The next visualization is from Andy Woodruff, cartographer and frequent eclipse traveler. This one is a "scrollytelling" visualization. As you scroll downwards the path and umbras move along in time, beginning in Mexico.

The umbra can be moved to any location for a precise look at what areas have the most and least coverage.

For reasons that I don't completely understand (maybe the sun's angle) the umbra flattens out as it progresses. By the time it reaches eastern Canada it is much more of an oval.
He also includes this nice, precisely detailed map of the Dallas area where you can see the eclipse's duration by neighborhood.
Woodruff ends his post with some advice and personal experiences from his eclipse travels. I like this map showing past eclipses he's seen with emojis representing the weather for each one.