The Guardian’s picture editors select photographs from around the world Photograph: Anthony Wallace/AFP/Getty Images Photograph: Hollandse Hoogte/Rex/Shutterstock Please enable JS and disable any ad blocker The 22nd “Festival Internacional del Chile en Nogada” in San Nicolás de los Ranchos will be held for two more weekends in August The small pueblo is located about 25 miles from the city of Puebla and because the road to get there is a one-lane road passing through several towns Chile en nogada is the iconic Pueblan dish A poblano chile is stuffed with different fruits It’s then covered with nogada – a walnut sauce– before pomegranate seeds are tossed on top bathing the dish in the colors of the Mexican flag “The idea for the fair is to showcase what we have in this region,” said Gumaro Sandre Popoca Municipal President of San Nicolás de los Ranchos “We have had this event for 22 years but in the beginning we started advertising more to let others know what products we have here There is no other fair like it in all of Mexico.” has been coming to the festival since its first year tempting passersby with a taste of her chile en nogada All of the ingredients in our chile en nogada are from this region.” Although virtually all cooks add some type of meat to their chile en nogada Ochoa said the dish was originally vegetarian – good news for us It looked like we wouldn’t be able to eat any of the chiles on offer until we spied a “Chile Vegano” sign at nearby El Riconcito “I got the idea because I know there are many vegetarians and vegans now,” said owner Guadalupe Rincón Amozoqueño We’d already eaten a large quesadilla but we had to try hers We’re glad we did because it was delicious gorditas and other traditional Mexican foods too – and plenty of places to grab snacks including helado de nogada –walnut ice cream with pomegranate seeds and parsley Efrain Huilotl Gallegos was selling his vinos artesanales fruit wines that proved popular with festival goers The world’s largest molcajete (the traditional mortar and pestle) made by Don Antonio Tlapanco Sánchez in 2009 80 cms high (a little over 2.5 feet high) and weighs 500 kilograms (1,100 pounds) Having your photo taken with it appeared to be a must There’s music – everything from mariachi to symphonic – kids rides live performances by Grupo Moros and others the festival is scheduled to make the world’s largest chile en nogada measuring 6 meters in length (almost 20 feet) and weighing 50 kg (1,100 pounds) Slices will be sold and the proceeds donated to local children with disabilities chiles en nogada is available in what feels like almost every restaurant across Mexico ADVERTISE WITH MND COMMUNITY GUIDELINES Subscription FAQ's Privacy Policy Mexico News Daily - Property of Tavana LLC Aerial footage captured over San Nicolas De Los Ranchos shows the Popocatépetl volcano erupting on June 13 known affectionately as “El Popo,” has been spewing toxic fumes ash and lumps of incandescent rock persistently for almost 30 years MEXICO CITY — Mexico's Popocatepetl volcano rumbled to life again this past week belching out towering clouds of ash that forced 11 villages to cancel school sessions The residents weren't the only ones keeping a close eye on the towering peak and a roomful of powerful equipment watching its every move A plume of ash and steam rises from the Popocatepetl volcano spewing out towering clouds of ash that forced 11 villages to cancel school sessions since it awakened from a long slumber in 1994 The volcano is 45 miles southeast of Mexico City but looms much closer to the eastern fringes of the metropolitan area of 22 million people The city also faces threats from earthquakes and sinking soil but the volcano is the most visible potential danger — and the most closely watched A severe eruption could cut off air traffic or smother the city in clouds of choking ash Volcanic ashes are especially dangerous for aviation not only because they reduce visibility but because they can act as an abrasive Mexico City's two main airports temporarily shut down operations on Saturday due to ash spewing from the volcano The city's Benito Juarez International airport suspended operations from 4:25 to 10 a.m resuming operations after removing volcanic ashes checking the runways and verifying favorable wind conditions located north of Mexico City and operated by the military suspended operations for five hours starting about 6 a.m Popocatepetl's explosions registered in the early hours of Saturday were more intense than in recent days but authorities — who keep a close eye on the active volcano — are maintaining the threat at an intermediate level Ringed around the volcano's summit are six cameras a thermal imaging device and 12 seismological monitoring stations that operate 24 hours a day all reporting back to an equipment-filled command center in Mexico City A total of 13 scientists from a multidisciplinary team take turns staffing the command center around the clock Being able to warn of an impending ash cloud is key warning times can be longer for the volcano and in general the peak is more predictable who works at the National Center for Disaster Prevention of Mexico gives an interview as he monitors the Popocatépetl volcano from Mexico City on Feb checking the readings at the command center run by Mexico’s National Disaster Prevention Center It is a complex task that involves seismographs that measure the volcano's internal trembling which could indicate hot rock and gas moving up the vents in the peak Monitoring gases in nearby springs and at the peak — and wind patterns that help determine where the ash could be blown — also play a role The forces inside are so great that they can temporarily deform the peak so cameras and sensors must monitor the very shape of the volcano How do you explain all of this to 25 million non-experts living within a 62-mile radius who have grown so used to living near the volcano Authorities came up with the simple idea of a volcano “stoplight” with three colors: green for safety For most of the years since the stoplight was introduced it has been stuck at some stage of “yellow.” The mountain sometimes quiets down It seldom shoots up molten lava: instead it's more the “explosive” type showering out hot rocks that tumble down its flanks and emitting bursts of gas and ash The center also has monitors in other states; Mexico is a country all too familiar with natural disasters Mexico’s earthquake early alert system is also based at the command center Because the city’s soil is so soft — it was built on a former lake bed — a quake hundreds of miles away on the Pacific coast can cause huge destruction in the capital A system of seismic monitors along the coast sends messages that race faster than the quake’s shock waves it can give Mexico City residents up to half a minute to get to safety Spectators watch the lava flow down the mountain from the Mauna Loa eruption the world's largest active volcano erupted Monday for the first time in 38 years Car are parked near an ancient lava field as a lava flow colors the sky above Mauna Loa cars drive down Saddle Road as Mauna Loa erupts in the distance In this satellite image provided by Maxar Technologies lava flows from the Mauna Loa volcano on the Big Island of Hawaii glowing lava and ash blasted and billowed from the world's largest active volcano in its first eruption in 38 years and officials told people living on Hawaii's Big Island to be ready in the event of a worst-case scenario (Satellite image ©2022 Maxar Technologies via AP) Spectators pull over on Saddle Road to watch the eruption on Mauna Loa Lava flows down the mountain from the Mauna Loa eruption Spectators take photos as they watch the lava flow down the mountain from the Mauna Loa eruption A spectator watches the lava flow down the mountain from the Mauna Loa eruption As the Mauna Loa eruption takes place in the background Despite local authorities enforcing a no parking zone in the area near the eruption site many spectators are flooding the area and illegally parking on the side of the highway The glow of the Mauna Loa eruption is seen through a grove of palm trees The Mauna Loa volcano is seen erupting in the background near Waimea Respond: Write a letter to the editor | Write a guest opinion Subscribe to stay connected to Tucson. A subscription helps you access more of the local stories that keep you connected to the community Get up-to-the-minute news sent straight to your device Ash and smoke billow from the Popocatepetl volcano as seen from the Santiago Xalitzintla community Mexico: Miguel Angel Atenco tries to ignore the vibrations falling ash and fiery night-time shows from the volcano towering over his Mexican town Like others living in the shadow of Popocatepetl located just 70 kilometers (about 45 miles) southeast of Mexico City just waiting to see what the volcano does," Atenco told AFP in his restaurant in the ash-covered community of San Nicolas de los Ranchos after sweeping the ash from the sidewalk in front of his business again "Don Goyo" as the volcano is also known locally has rattled nerves with several explosions and repeated emissions of ash The increased activity caused dozens of flights to be canceled over the weekend out of Mexico City Shelters have been opened near Popocatepetl in case the situation escalates while troops have been deployed and are helping to sweep up ash in the streets Roughly 25 million people live within a 100-kilometer radius of Popocatepetl rising nearly 5,500 meters (18,000 feet) above sea level authorities increased their warning level to one step below red alert would mean evacuation for thousands like Atenco living near the volcano whose name means "smoking mountain" in the indigenous Nahuatl language Although the volcano's explosions send chills down the spines of locals the latest burst of activity is not very different than others seen since it awoke from decades of slumber in 1994 Popocatepetl saw similar episodes in the late 1990s and early 2000s although the current phase could potentially "go in a more dangerous direction," said the National Autonomous University of Mexico researcher intense activity blanketed parts of Mexico City in thick layers of ash which can cause respiratory illness and clog drains Experts are constantly monitoring seismic activity around the volcano as well as the composition of the materials and gasses it spews out to try to predict a possible major eruption "Volcanoes have a somewhat capricious activity," Espindola said President Andres Manuel Lopez Obrador sought to calm public concerns on Wednesday "It seems that 'Don Goyo' is calming down although it's still emitting ash," he said Authorities have warned people not to go within 12 kilometers (7.5 miles) of Popocatepetl and to use face masks due to the falling ash Some residents living near Popocatepetl left over the weekend after volcanic activity caused their houses to vibrate After a lifetime living in the foothills of the volcano despite the fact that in recent days "even the roofs were shaking." "We're not going to be scared," he said 2013 10:10 PMHow much pressure did it take to pop the top off Mexico's Popocatépetl volcano?On June 17 the Popocatépetl volcano in the state of Puebla in Mexico belched out a pretty impressive looking volcanic plume I’m guessing this explosion didn’t come as big surprise Popocatépetl is […]A map of Popocatépetl (A) and San Nicolás de Los Ranchos (B) Copyright TerraMetrics and GoogleSave this storySaveSave this storySaveOn June 17 Here's the video (it's been sped up): who have also restricted access to anywhere within 12 kilometers of the crater you can actually see the clouds react to the explosion just a little while after the plume emerges That's when the shock wave of the explosion (the BOOM) hits the clouds The other thing that struck me was the incredible amount of stuff that's rolling down the volcano's slope *really* fast Here's how Wired blogger and volcanologist Erik Klemetti describes what's happening: and you can see after the initial explosion is how the clouds of water vapor around Popocatepetl shudder as the explosion front moves past the upper flanks of the volcano turn grey from the rapid raining out of ash and volcanic debris (tephra) Let's find the distance that the debris travels Then we'll time how long it took to cover that distance which actually tells you where the webcam is located a town that's about 15 kilometers (9 miles) away from the crater I zoomed in to the volcano on google Earth and put down a marker at the center of the volcano (where the debris came from) and three more markers lower down on the volcano slope The reason for putting three markers on the right is so I can take the average of three distance measurements I can actually fly over to San Nicolás de Los Ranchos and see if those markers are at the right place The markers are pretty much where the debris stops sliding in the video here's a video of what the explosion would have looked like to residents of San Nicolás de Los Ranchos I made this by landing on the town in Google Earth and then lining up the video volcano with the Google Earth volcano (the video is still sped up It just blows my mind that we have access to a life-sized map of the world (without stepping outdoors A top view of the distances between the markersA closeup where you can see the terrain.The average of the three measurements was 3.31 kilometers That's the average length of one of red paths I see that the volcano let out the plume at 13:23:38 Depending on what part of the debris you want to consider it reaches the treeline somewhere between 13:24:22 and 13:24:46 So it took somewhere between 44 to 68 seconds to reach that point The slow estimate puts it at 49 meters/second (109 mph) and the fast estimate puts it at 75 meters/second (168 mph) I decided to check my calculation by putting another marker half way down the mountain and timing how long it took the plume to travel this new distance Here's what the mountain looks like with the new marker on it (it's a little hard to see but there's a fourth pin halfway along the red line): The distance to the halfway marker was 1.64 km I think these numbers are a bit more reliable than before and you get a speed of 63 meters/second or 140 mph that's basically the same number from before Given the huge uncertainty in our speed calculation and the various factors like gravity and friction that can change the speed I'd conclude that 140 mph is a pretty good estimate of the speed of debris flow down the volcano because they give you some insight in exchange for not a lot of work Picture the moment that the volcano explodes At the top of the volcano sits a chunk of rock that's being pushed up from the inside by high pressure gas We can use an equation called Bernoulli's equation to relate the pressure at the top and at the bottom of this chunk of rock $latex P_{inside}$ is the pressure inside the volcano at the moment before it explodes $latex P_{outside}$ is the pressure outside the volcano at this moment which is good 'ol atmospheric pressure ρ is the density of mud sitting on top of the volcano And $latex v$ is the speed of the rock at the breaking point I'm assuming that this is somewhere near the speed we calculated above What's the density of mud at the top of a volcano "the density of the rock overlying the gas reservoir" of a volcano is about 2,300 to 3,000 kilograms per cubic meter (I'm glad I'm not the grad student who had to measure that) and we get that the pressure that built up inside Popocatépetl before it exploded is about 54 atmospheres BOOM. 600 psi. That's about the pressure inside a paintball gun except imagine thousands of paintball guns aimed at one heck of a paintball It's also the water pressure at a depth of about 400 meters which is about as deep as most submarines can venture Is this number even in the right ballpark? Fortunately, I found a PhD thesis that builds a detailed scientific model relating the pressure inside a volcano to the speed of the eruption this model was built specifically to understand the Popocatépetl volcano in Mexico (science - it's the gift that keeps on giving) the author basically heated and squeezed volcanic rocks and then measured how much pressure it took for them to give way The data includes rocks from an eruption of Popocatépetl in 2003 The vertical axis represents the pressure that it takes to obliterate the rock or millions of Pascals (to go from MPa to atmospheric pressure The horizontal axis has to do with how porous the rock is The figure includes data using rock from many volcanic eruptions (including some real famous ones) but take a look at the blue stars - that's data from Popo (aka the big P) Figure from the thesis of MA Alatorre Ibargüengoitia Multiply by 10 to convert MPa to atmospheres.Depending on how porous the rock is the pressure needed to cause an eruption at Popocatépetl varies from about 50 atmospheres to 200 atmospheres That cluster of blue stars on the right - they're all at around 50 atmospheres So our calculation of 54 atmospheres for the pressure inside Popocatépetl before an eruption is probably within a factor of 2 or so from the actual result It's also where I got the number for the density of rock in the top of a volcano volatile content and ejecta velocity in three types of volcanic explosions Journal of Volcanology and Geothermal Research A model of volcanic explosions at Popocatépetl volcano (Mexico): Integrating fragmentation experiments and ballistic analysis. MA Alatorre Ibargüengoitia. It is the essential source of information and ideas that make sense of a world in constant transformation The WIRED conversation illuminates how technology is changing every aspect of our lives—from culture to business The breakthroughs and innovations that we uncover lead to new ways of thinking