Laguna Seca: where summer meets winter (1/3)

Intro: lack of oxygen, excess of radiation

Bolivia is entirely situated in the tropical belt, but due to the huge differences in elevation has a diverse and complex climate. While the eastern part is dominated by wet lowlands and savannas, the western sector is mostly a high and dry plateau named the Altiplano. With an average elevation of around 3800 meters, this barren highland which is shared with three other South-American countries (Peru, Chile and Argentina) is the second largest and elevated in the world after the Tibetan Plateau, concomitantly the air contains only about 60% of the oxygen found at sea level.

The driest part is represented by the westernmost stretch, which gradually descends into the hyper-arid Atacama desert towards the coast of the Pacific Ocean. In Bolivia it can be found in the south-western corner of the country. In the middle of this region there is an extensive flat area covered with thick salt crust named Salar de Uyuni, which represents the closed bottom of the highland’s interior. As such, it has no outlet and all the rivers (mostly intermittent) are collected by the huge, shallow bowl where the water rapidly evaporates in the thin and dry air.

With more than 10.000 square km surface area, Salar de Uyuni (3660 m) is the largest salt flat in the world

The climate of the plateau is extreme. Especially notable are the daily temperature fluctuations, which can exceed 30 degrees in the dry season, which has its peak in the south hemisphere’s winter months (June-August). Beside the huge thermal amplitudes the other peculiar weather aspects are the strong westerly winds and the intense UV radiation. Regarding the latter, the highest value ever recorded on the surface of the Earth – an incredible 43.3! – was measured on the peak of Licancabur volcano (5916 m) situated right on the border between Bolivia and Chile on the fringes of the Atacama. Just imagine that the level 11 is considered “extremely high” on the UV chart and most European countries never reach that even in the summer.

Choosing the target

While already knowing that the Altiplano likely provides the best general context regarding the biggest daily temperature fluctuations, I was of course interested in the “finer details” which can maximalise this potential. Regarding the timing I concluded that the best period must be somewhere near the equinox, when the heating and cooling has similar chances of manifestation. As with both very short nights (think of polar summers) or very short daylight (think of polar winters) the thermal amplitudes are pretty small (constantly cool or constantly frigid), the biggest ones have to be equally far from both.

The location of the research area (black dot) inside the Altiplano (gray spectrum)

Concomitantly, much better is to have an abrupt sun-path, where the irradiance reaches the highest possible angle at zenit (namely tropical latitudes). This is of course influenced also by other factors such as the distribution of moisture (clouds and precipitation) between the seasons.

Taken all into account the month of September stood out as according to the available climatological statistics (Uyuni in Bolivia, Calama and San Pedro de Atacama in Chile) in the south-western part of the Altiplano it is the same dry as the mid-winter period, receiving almost no precipitations. Now let’s move to the topographical aspects.

Topo-map with the unnamed depression (lower-right center) situated east of the Alota – Villamar Mallcu dirt road

As the thinner air has less heat-retaining capacity, the general rule to follow is: the higher the better. In the simplified version the limitation is given by the highest possible elevation where closed basins can be found as in those places the colder air can be gravitationally collected. But there are also other influencing elements like the wind pattern, which instead is inversely proportional with the targeted amplitude potential, making the real picture more complex. Best should be (especially for shorter term observations like mine) to make a wise compromise, founding the “golden mean” between elevation and stability.

As such, I concluded that around 4000 meters elevation must be a well grounded decision, sufficiently high to have a serious advantage compared to the low elevations, but still relatively stable compared to the protruding tall ridges and peaks where the wind is certainly more active.

Satellite view of the endorheic basin with the contour levels 30, 20, 10 and 5 meters marked with red

Meticulously scanning the map I found out that there are only a few closed basins with sufficient depth which doesn’t have lakes on their bottom and of course exactly these are the best for my purpose. Finally I’ve chosen an unnamed depression south of Villa Alota settlement, whose floor is situated around 4030 meters, while the outflow point is some 30 meters higher. The bottom looks completely dry, lacking even the characteristic white salt crust.

Brief summary of the research

The Bolivian journey started on 13th September, landing in Santa Cruz de la Sierra, the biggest city of the country. Continuing with an internal flight to Sucre, the next day I reached an intermediate elevation between the hot lowlands and the arid high plateau. After two other days of acclimatization I arrived in Uyuni on 16th by bus via Potosí. On 17th I traveled to Villa Alota with a previously hired private jeep to begin the research as soon as possible, approaching the chosen spot a little more on the dirt track towards Villamar Mallcu. I started the hike with the equipment around 1 PM.

View of Laguna Seca from the west

After around 1.5 hours I reached the bottom of the nameless endorheic basin where the instruments were mounted on the tripod, which was also stabilized with an attached bag filled with rocks. The coordinates are 21.498 S, 67.547 W, the elevation around 4030 m and the distance of the sensor from the ground is 170-180 cm. The weather station started its operation at 2:56 PM. First reading: 14.4 degrees Celsius.

I did not waited long here, but returned from Alota the next day to spend the following two nights near the equipment. In all three cases the temperature dropped below -15 degrees, the coldest being the third morning with -16.5 degrees Celsius. The sky was generally clear with some altocumulus invasions during the evening and the first part of the second night. The wind pattern has a pretty obvious course, the afternoons being dominated by strong westerlies, while the nights and mornings are much calmer. I left the research spot in the morning of 20th and spent the following days in and around Uyuni.

The weather station on the bottom of the basin

After six days I returned to the endorheic basin for one last night after which the equipment was collected. That morning (27th) was the coldest of the entire research (-19.0 degrees Celsius at 6:23 AM) and it was also the period when the biggest thermal excursion happened: 38.1 degrees in under 24 hours, starting the huge drop from the previous day’s positive 19.1 degrees.

Six out of ten days the temperature fluctuation exceeded 30 degrees (dropping every time below -10) with a very likely seventh (the day before the last) when the strong afternoon wind overturned the tripod disconnecting the sensor. The middle days were somewhat milder, when at times I observed partly covered sky in the Uyuni area.

The coldest morning of the research was the last one

During my solitary hikes I saw many llamas on the outer slopes of the basin, where the locals have started the spring work on the quinoa fields and only vinunas inside, on the bottom. I spotted also some eagles, a viscacha and observed Darwin’s rhea (suri) tracks in the sand. Near my camp which was situated a little higher on the northern slope I identified signs of smaller scale mining activity. Except the relatively busy dirt track where the tourist filled 4wd cars circulated the surroundings lacked human presence, meeting only once two llama herders on the periphery of the basin.

The instruments used in the field

-One LogTag UTRED30-16 data logger with the measuring range between -40 and +99 degrees Celsius, an accuracy of 0.5 degrees Celsius and a resolution of 0.1 degrees Celsius

-One Greisinger G1710 thermometer with the measuring range between -70 and +250 degrees Celsius, an accuracy and resolution of 0.1 degrees, used for instant hand measurements

-One photo camera tripod serving as the support for the instruments

-One helical solar radiation shield from Barani Design Technologies: https://www.baranidesign.com/

The Barani Pro shield fighting against the vicious UV radiation

To be continued…

Laguna Seca: where summer meets winter (2/3)

Journey photo album

Catedral Metropolitana Basílica de San Lorenzo, Santa Cruz de la Sierra: My plane landed at Viru-Viru airport on 13th September where hot wind (around 36 C) and haze greeted me. Feels also pretty humid. Not the weather I came for, but certainly an interesting debut.
The city has a rapid pace, maybe too rapid for my taste. You must be careful with the traffic, the drivers does not have much patience here. At the central square is better. During the night the weather changed, cooling down significantly (around 20 C) because of the torrential rain. Only the wind remained there from the old equation. Back to Viru-Viru, as I have local flight to Sucre.
Big festivity in Sucre: With some delay the plane landed at Alcantari aiport (3100 m elevation), around 30 km from the city (2800 m). Taxis are not expensive here. While Santa Cruz (400 m elevation) has some dodgy neighborhoods and can be challenging during the night (I didn’t tried out), Sucre feels much more safe and is also cleaner. Let’s forget about the mess after the mega-party, it was rapidly cleaned the next morning. Not my head which was heavily strucked by “soroche” (altitude sickness) because of the rapid change from near sea-level. It was kind of surprising, never felt ill at this elevation until now.
At “Jesus’s heart” monument the next day: Around noon my condition improved, so went out to do some mild cardio workout. This hilltop (300 meter elevation gain) was a good choice to check the gears. The communal cohesion is evident in the city, which is known as the second capital of Bolivia. Locals may say it’s the real one.
Also known as “the white city”, with its general colonial aspect, Sucre has a positive and tranquil vibe
Yes, those are palm trees at 2800 meters. The climate here is one of the best in the country, which can be summarized as a constant spring. Not hot, not cold, not too rainy, not too arid. But don’t underestimate the UV radiation, which isn’t modest.
Potosí historical center: Reaching the heights of the Altiplano (almost 4000 meters) the next evening by bus, I felt in my elements both physically and emotionally. The soroche didn’t returned. I’ve read before that the body’s reaction to the high elevations are pretty unpredictable, now I experienced it live again.
Similar in its colonial aspect with Sucre, Potosí is dominated by pastel colors (especially pinkish), which gives him a more ancient general look. While Sucre can be considered the heart of national identity, here is the center of the spanish heritage. Pleasant cool morning, around positive 5 degrees between the old walls.
Statue of liberty: nice hyperboloid shape by the way
Yeah, definitely has a soul, I think it’s my favorite bolivian city
View from a tower towards Cerro Rico (4780 m), the famous mountain which had the biggest silver mines in the world in the 16-18. centuries, strongly contributing to the rapid ascent in power of the Spanish Empire. Still a lot of inner richness there in our days. Well, take this literally, the actual story behind the exploitation is less appealing from a humanistic perspective.
Villa Alota: After another 4 hour bus journey to Uyuni, only slept there once as I felt rushed by the good weather conditions to start the research as soon as possible. Having a previous arrangement in this regard to hire a private jeep, we reached the very basic looking settlement on the new paved road before noon. It was windy as it can be, what a start!
Flamingoes in the wetlands (bofedales): I decided to stay 3 days in the area, spending the latter 2 in the wilderness, while in this first one I will sleep in Alota after placing the measuring equipment. The forecast shows the best conditions for the second and third night, that’s why.
Henry, the driver with a lonely altocumulus lenticularis above: Continuing on the dirt track in the direction of Villamar Mallcu around 15 km, we approached the chosen place more and before 1 PM I started the hike
Above 4000 meters elevation: O yeah, I was waiting for this from a long time. Too bad, my GPS died right at the starting spot (could be the dust or just bad timing?) Anyhow I have everything crucial in my memory, let’s get into it.
First view of the endorheic basin: It seems that I guessed the directions right, the edge of the depression wasn’t too far. The weather is still windy, though less than in Alota where was on the border of violent. The temperature is moderate. Unsurprisingly, nobody in the entire area.
Reaching the bottom around 2:30 PM, I mounted the instruments on the tripod, secured it with an attached bag (actually the tripod’s own) filled with rocks collected near the slope and shortly before 3 PM the logger was started: 14.4 degrees Celsius, must be around the hottest time of the day. The wind persisted.
First milestone, happy with the installation
Even flatter than I thought, the bottom of the basin is situated around 4028 m according to Google Earth. The vegetation is made up mostly by separate patches of Paja Brava (Festuca orthophylla), which often grow in this characteristic circle arc format.
Must have been vicuñas (wild relatives of the llamas), I saw a few running in the distance in the eastern part of the basin. Planning to reach Alota before dark, I left the research area already before 4 PM. Isn’t really a must, but I’m a guest in the village and not sure about the quechua ethics regarding the dinner.
Llama herd on the outer slopes
The track I follow on the way to the village is flanked by quinoa fields. Beside the llama meat this plant is the other basic food of the local population, between the very few which can grow at these elevations. It seems that the spring work (sowing) has already started in some parts.
Trying to do a shortcut as the road turned too much to the left, around sunset I reached the wetland situated south of the village
Beside the flamingoes this is a very common bird species here. Sometimes they will fly round just a few meters above your head, while screaming. Not a welcome sign, I guess.
Altocumulus lenticularis is by far the most common cloud type here. Must be very windy at the highest elevations.
It seems that I will not make it to the village during daylight. The marshland’s topography forced me to turn to the left myself too, like I was corrected by an invisible quechua policeman because I did not follow the local rules. No bad feelings, I really like the ambiance here. More adventure, the better.
Am I right?
Okay, I reached the bridge
The cool evening wind is an early precursor of the cold night what will follow it. I reached Alota shortly before 8 PM after an almost 20 km hike, much more than the direct line which shows only 12 km.
Early morning in the remote village, the sky is clear, the wind has gone
Far from the previous day’s sunny afternoon
You can buy coca leaves here (legal in Bolivia), a mild to medium (if you chew as much as a cow) stimulant, frequently consumed by the locals. Be sure your mouth will feel numb as after a visit to the dentist.
The small green bag on the big one: As you can see I’m prepared for the long hike, three sunny days (read it as UV blast) and two cold nights are waiting for me
The weather warms up quickly and the first daylight hours are basically windless. This seems to be a general pattern here, which often extends to around noon, the wind starting to increase only in the early afternoon.
The work of the night
The wetland has a rich and variate fauna even in the dry season, beside the bird species there are many llamas, sheep and even bovines
As I heard they leave the area only in the winter months (June-august), so possibly returned here not long before
First I want to visit a canyon area, which is situated a few km’s to the east from my main target
The warming continues, without wind the temperature differences are very noticeable
Reaching higher elevations, I continue the hike on rougher terrain
Like it was cut by a giant guillotine
The top part is very fragmented, thus after meandering my way through the rock-labyrinth for some time I concluded it’s a bad idea to continue, trying to go round all these ravines and decided to return before heading to the endorheic basin. I have a heavy backpack with limited water for a big and more strenuous bypass. Let’s be reasonable.
NO, the decision is fixed
Noon approaches. One can almost sense the UV burn just looking to this picture.
Extensive quinoa fields on the other side, a reminder that this barren place is not entirely forgotten. Jubina mountain is in the right side of the background, that’s my direction.
The water in the stream is surprisingly balmy. I suppose it’s a hot spring area, I don’t think the daily warming itself could do this. However, careful with the drinking, many llamas are present in the surroundings. I mean DON’T.
Crossing the terrain transversely is not that straightforward even is there are no topographical obstacles of major scale
Or are?
I see now, that’s actually the main canyon, the more visited one. I was in a secondary one, though likely the same spectacular. Maybe I miss the GPS a little.
Crossing the shallow river. If not before, now I am using the “legionary hat” as my face started to feel the abrasion caused by the intense radiation. And not only the face. The exposed parts of the skin (which are pretty large as I am wearing shorts and T-shirt) are continuously attacked from various directions. Doing a lot of outdoor activities in all seasons from many years, I think that never felt burning sensation on my arms and calves before since childhood. But you can’t really prepare to this level of UV intensity (13-14 now), it’s clearly above the European scale.
Another small scale ravine on the other side. Look, a viscacha! Oh, it’s gone, had no time to record it. Very quick, likeable creatures, with their appearance somewhere between a rabbit and a squirrel.
The campesinos (local farmers) working on the quinoa fields. Well, even if they live here from centuries, are fully clothed and are using hats…
A little later I reached the dirt road where the 4wd cars circulate towards Laguna Colorada and the Siloli desert. Jesus’s heart was present and I received a full bottle of water (did not asked for) from a kind female tourist after stopping to curiously ask what the heck am I doing here alone with a heavy backpack. Now I’m sure I will stay both nights outside.
Reaching the col of the basin. The slightly undulating terrain was misleading as there were more topographical discontinuities than one could conclude simply looking from the distance. A little tired until now, the elevation taxes you and it’s different with a bigger luggage.
On the cracked bottom of Laguna Seca, which locals told me is the name of the place studied by me. Proper name.
WHAAAT !? This was one of the biggest and most pleasant surprises of all my cold-hunter career until now. NINE degrees below Alota, which itself is already on the bottom of a flat basin? This is the definition of a Jackpot. And the following two nights could even beat that! How about the 33.3 degree amplitude?
Yeah, some vivid colors there. Maybe I too should have used Mr. Barani’s helical radiation shield?
After scanning the surroundings I decided to spend the night a little higher on the southern slopes of Jubina mountain. Spotted there a rudimentary building, which later identified as related to a nearby small-scale mining activity. Shortly after I changed my mind seeing a lot of rodent feces in one corner inside the rectangular walls. I like animals but don’t want to wake up with jerry on my face…
More exposed to the elements, but another level of freedom. Good night! Wait, it’s only around 5 PM or so.
Park ranger feeling. Not the best payment, but nice view.
Now seriously: Good Night!
Was the night good? To be honest, far from my favorite one. Despite the optimistic forecast regarding a completely clear sky, from the late afternoon well into the second part of the night there were constant altocumulus invasions like the place was seriously cursed. And the previous one – which I decided not to spend here – was spotless, despite the forecast showed partial cover. The westerly clouds are just coming and going, but never disappearing completely. I fell asleep late, but when woke up around 4:30 AM the sky was clear and there was barely any air movement. Great! My thermometer showed -3 degrees, must be a strong inversion down there. Soon I was ready to an early morning visit to the weather installation.
Indeed, in the lowest part of the basin it suddenly felt colder. The air was completely still. I guessed well, the minimum is well below -10, but less cold than the previous morning. Not bad after the altocumulus marathon.
No T-shirt time anymore, the lack of rest also weathered me a little
Sunrise above Cerro Tomasamil (5890 m), the highest peak you can see from my research spot (around 50 km as the bird flies)
That likely was a vicuña, but what killed it? A cougar (puma) could be part of the equation, no doubt
Around 8 AM already reaching the positive range, that’s a serious leap!
Lord of space and time
This is what I talked about a little earlier: there are a few crevices in the rock nearby, which evidently are anthropic. Then I remembered the conversation with the quechua woman in Alota regarding Jubina mountain: “it’s very rich, silver, gold and many other”. Maybe they think I am a gold-digger in disguise?
Until the early afternoon he weather warmed even above yesterday’s maximum. You can’t really comprehend it’s the same day on the same spot.
Maybe only the pretzel shaped tufts of paja brava know what this remote basin’s climate is capable of
The second night was completely clear, though somewhat windier in the evening. As at dawn the mobile thermometer showed -5 degrees at my camp, I knew it will be even colder on the bottom this time. And it was: -16.5 degrees, the lowest temperature until now.
The golden mantle lowering into the depression
I left the research spot in the morning and hiked back the roughly 20 km’s to Alota. This must be the dwelling-place of a llama herder, but nobody at home now.
Gotcha! Culpeo fox
The vicuñas are the ancestors of the alpacas, also related to the llamas. Very common on the Altiplano, you can spot them often near the road while passing by car.
Hitchhiking around noon in UV-strucked Alota. A few years ago the road was paved, so now it’s pretty easy to reach Uyuni with basically any means of transport. I was lucky that the Calama bus (from Chile) passed there less than 30 minutes after my arrival and of course the fare was very cheap.
Train graveyard in Uyuni: Until the late 19. century the silver mining in Potosí declined thus the carriages transporting the mineral to the Pacific coast through the Atacama were left pray to the time and elements.

In the evening of the return I observed signs of a respiratory infection which intensified the next day (likely flu), so I decided to take some rest. Regarding the original plan this meant a single important change: there will be no climbing. Hard to accept it, but that was the proper rational decision. I have to return to collect the equipment in less than a week, so I will not play the Russian roulette. That’s it, next time. I still went out to visit the train wreck at the periphery of the town. Interesting, but…
too bad for the garbage field you have to cross from and to the settlement if you come by foot
My condition didn’t improved – to say the least – so stayed mostly inside the following day, but afterwards I felt somewhat better and went out to a walk again. This time the purpose was to identify the weather station, which I concluded it must be somewhere in the area of the airport (some 5 km from the center). I want to visit it and, if possible, obtain some data to compare it with my measurements. As I couldn’t see it from the road and did not know the local rules regarding the airport security (saw soldiers patrolling inside the fence), decided to return and ask the hotel staff regarding this.
My hotel room
Feeling stronger it was time for a longer trip. I visited the Salar de Uyuni, one (more correctly THE) of the country’s main attractions. At 3660 m elevation, the extensive saltpan is the worlds largest measuring over 10.000 square km and almost 150 km across. You heard it right.
As in case of many other scenic places, tourists arrive here through organized group tours (one or more days) by jeep. However, for eccentrics like me is more palatable to do this “freestyle”, so I reached Colchani village by bus (less than US $1) and continued by foot. From the asphalt it’s 4-5 km to the edge of the salar. Under the spell of the infiniteness I could not resist and just walked and walked forward. After a while I saw something in the distance, of which first wasn’t sure if are cars (there is also some exploitation near the shore) or some flatter buildings, but later turned out to be the latter. It was a complex built in and from salt. For tourists of course.
Does it look a little like Antarctica maybe? Be sure, it’s only the look as the UV radiation is at a different level here.
The place is named “Dakar Monument” and concluding from the walking time must be around 8-9 km inside the salar
On the way back. Convective clouds are evolving above the eastern ranges (towards Potosí). The hike was technically easy (very flat) but pretty long (26-28 km) for a “warm-up” after the flu. However, the distance per se should have not be an issue. The problem was the notorious radiation, more specifically the reflected one. I read that a sunglass is a must here, but as I didn’t felt anything suspicious regarding the vision while hiking, just continued without protection. Bad decision. The inflammation started only in the evening and wasn’t over the next day. How can I describe the sensation? Well, imagine that your eyelashes became your worst enemy. You can’t close them because they will feel like wires scratching the surface of your eyes. So, good night…
On the third day following the UV incident my vision improved sufficiently to can safely return to collect the equipment. It was also the planned date to do this. After some less potent days, the forecast shows a new cooling in progress, so I was optimistic regarding this last night which I will spend in the wilderness. Taking the Calama bus at dawn, started the hike from Alota in the morning. It was pretty chilly, definitely below -5 degrees. This time I continued to stay on the main road more, turning left towards Jubina only after about 12 km’s. Reaching the periphery of the closed basin I observed two people so entered in conversation and found out they are herders searching for some missing llamas. Told them I only saw vicuñas inside the basin.
Reaching the bottom I tried to identify the tripod as soon as possible, but as I approached it became clearer and clearer that something is wrong. The suspense was over after finding the structure in its place, though overturned. So: wind, animal or human? Turned out to be the first as both the falling direction (towards east) and the time of the incident, which I concluded later from the interrupted graph (between 3-4 PM) supported this theory. As the weight-reinforced installation felt pretty stable and easily bearing the first days wind, those gusts must have been wild.
Inspector gadget is back
Restoring the measuring equipment
Around noon the radiation was over the scale again, hard to found a shelter in this period as the sun is very high on the sky
Feeling well, decided to do a hike to the top of Jubina
Queñoa (don’t mistake it for quinoa), the highest living tree in the world has an easily exfoliating surface
The other endemic plant of the highest elevations is the Yareta (the moss looking one), which often lives in a symbiotic relationship with the former. But don’t be fooled of the aspect, it’s hard as a rock.
Wind and UV: On top of Jubina (around 4400 m). I wouldn’t consider it a “true climb” – in the bigger context it’s more like a hill here – but it was the highest point I reached during the journey. RIP Garmin watch, I lost you here...
Maybe my favorite plant? Definitely special.
Close-up of a yareta
Almost like another planet
The thick foliage of the queñoa evolved to can endure the drought and the strong wind of the barren plateau
Panorama of Laguna Seca
Alota in the opposite direction
Uturuncu (6008 m) the highest mountain in southern Bolivia and the salt flats of Laguna Yapi (4000 m). The whitish top of the mountain is not snow, but volcanic debris
Zooming the bottom of Laguna Seca. Yes, I can spot the weather installation.
Descending the rocky slopes. The return to the camp was straightforward and also much faster then the wandering on the bumps of the plateau
Colors and waves of the Altiplano
Are you looking for me? Not today.
IR and UV are gone
Last morning temperature check: The evening and night was completely clear and also the calmest of all, thus the temperature plummeted extremely low, reaching -19 degrees just before sunrise. What a finish!
Some martian vibes
The endorheic basin exceeded my expectation
The research is over, the results are excellent
Darwin’s rhea (Suri) tracks in the sand near the basin’s col
The hike back to Alota was the same long (if not longer) as this time continuously followed the trails between the quinoa fields, without trying to do shortcuts
Arriving to Alota space center 🙂
Guardians of Uyuni. After hitchhiking for a while, a truck coming from Chile took me back to the town, same cheap as the bus.
Some soviet influence?
Everything is revolving around tourism in Uyuni, the small town is full of agencies, accommodations, souvenir shops and small restaurants. But of course, I was more interested to get in touch with the weather station. The problem was resolved with the helpfulness of the hotel staff who arranged a meeting with the weather personnel of the airport. The data I obtained there is valuable (see the third chapter)
A lost sherpa? The descendants of the incas might be of smaller stature but they’re far from weak
Nothing more bolivian than this colorful load-pack
It was time to start the return. Following the same way by bus, first I reached Potosí
The well decorated “church of indians”, unfortunately not open for visitors
The top of San Francisco church overlapping with the pyramidal peak of Cerro Rico (author’s fault)
Now the “Casa National de la Moneda” was open and I take the opportunity to visit it in the last hours of my stay. It’s Sunday and pretty crowded because of the short program, but worth the patience.
“Triangular virgin”, a mix between the new Christian religion and the older native mountain veneration
Some old coins from the early minting style (16-17th century)
Inside the chamber with the huge gears which operated the mint
In the mineralogy sector
There is even a church inside
Pieces of art made from the abounding local silver
The next day I continued the bus trip to Sucre
Despite the poor statistics in comparison to other South-American countries, Bolivia’s “second capital” radiates a general feeling of prosperity and proudness
Uncheangedly white
From Sucre I descended to the savanna climate of Santa Cruz with the 45 minute local flight. The same journey would take 11 hours by bus and the cheap prices support the good decision. Again hot and windy. And dusty.
At the local zoo
Only South-American fauna
Not the car…
…but the same strong and fast
He just stood up and elegantly walked like this for a while, before changing into tree-acrobatics mode
Nandu. A smaller relative lives also in the Altiplano (remember the tracks in the sand?)
The geometrically designed armadillo
Well, I think we’re not completely done here. Hasta luego, amigos!

to be continued…

Laguna Seca: where summer meets winter (3/3)

Interpretation of the logger’s graph (using LogTag Analyzer 3 software)

The temperature curve of the 10 days/ 10 nights research period. The device was registering a value every 2 minutes.

First day and night (17-18th September)

I installed the measuring equipment on the bottom of the endorheic basin in the early afternoon during moderately windy conditions and almost clear sky. The logger set for 2 minute intervals was started at 2:56 PM and the first reading showed 14.4 degrees Celsius. Concluding from both the time of the day and the temperature curve it was around the hottest part of the day, reaching the slightly higher maximum of 14.7 degrees at 3:25 PM. I left the equipment before 4 PM and hiked back to Alota under generally clear sky with some altocumulus lenticularis clouds over the higher mountains. The moderate wind persisted also in the evening.

The temperature curve of the first afternoon and the following night

After a smoother afternoon start the temperature drop is slightly disturbed in the evening and night but generally is pretty straightforward. Descending below 0 for first time at 10:35 PM, the continuous negative values started right around midnight. The minimum of -16.2 C was reached at 5:11 AM and was approached again with -16.1 C at 6:25 AM before sunrise. I spent that night in Alota and measured -7 degrees outside in the early morning during clear and calm conditions.

Second day and night (18-19th September)

After sunrise the temperature rise is fast and clean, already passing over 0 degrees around 8 AM. Later the curve becomes less and less abrupt but has a general constancy until around 3 PM, reaching the peak of 17.1 C at 3:49 PM. Together with the -16.2 C morning minimum this means a 33.3 degree temperature excursion in the same day. The obvious drop starts around 4:30 PM becoming more pronounced after 5:20 PM. Like in the previous night’s case, the afternoon drop is the cleanest while the evening and first part of the night somewhat disturbed, still without significant changes on the higher scale. The 0 degree mark was passed for the first time at 11:21 PM, while the continuous negative values started from 0:45 AM. The minimum of -15.2 C was reached at 6:17 AM.

The temperature curve of the second day and the following night

I spent the night in the basin at my camp situated a little higher, outside the inversion layer on the southern slope of Jubina mountain. Despite the optimistic clear forecast, from the late afternoon well into the night there were constant altocumulus (also cirrostratus) invasions, passing from west to east and partially covering the sky between 1/8 and 5/8 ratio. The wind was generally weak, reaching the lowest speed at dawn when the sky finally became completely clear. I was present at the research spot during the coldest period before sunrise and observed calm conditions on the bottom.

Third day and night (19-20th September)

I continued to stay in the basin observing an all day long clear sky. The very rapid temperature rise passed again above 0 degrees around 8 AM, the curve becoming less abrupt before 9 AM. This time the maximum of 17.8 C was reached a little sooner at 2:15 PM, which together with the -15.2 C morning minimum represents a 33.0 degree daily amplitude. The warmest early afternoon period is characterized by pretty big 1.5-2 degrees small scale oscillations in short periods of time. The general drop started after 4 PM and again the cleanest part was the late afternoon. The evening and especially the night was less stable, where a 5 degree warming happened around 2 AM and only after that started to drop rapidly again. It reached below 0 for the first time at 11:17 PM, while the continuous negative temperatures started from 0:35 AM. The minimum of -16.5 degrees Celsius was reached at 6:03 AM, thus slightly exceeding the first nights low.

The temperature curve of the third day and the following night

I was present in the area, spending the night at my camp and checking the logger in the coldest early morning period. During the dark hours I observed no clouds at all and only weak, sometimes moderate wind on the slope. Regarding the earlier mentioned abrupt night warming, as I can’t recall any clouds on this night, the disturbance was likely caused by wind alone. On the bottom was calm again at dawn and morning.

Fourth day and night (20-21th September)

I left the research area after sunrise and hiked back to Alota from where traveled to Uyuni by bus. In Alota was still completely clear and close to calm around midday. The diagram shows the characteristic undisturbed morning warming, passing the 0 degree mark again around 8 AM and continuing the rapid increase above 6 degrees Celsius at 8:50 AM. With a more moderate but still generally constant ascending slope, the peak of 18.4 degrees was reached at 3:09 PM, which together with the morning’s -16.5 C represents an impressive 34.9 degree daily amplitude, the biggest until now.

The temperature curve of the fourth day and the following night

The obvious drop started after 5:30 PM, again cleaner in the late afternoon and more fragmented in the evening and night, but keeping the big lines. This pattern seems to be a generality here. The continuous negative values appeared early on at 9:57 PM. This time the lowpoint of -14.6 degrees was reached earlier, around 4:30 AM as after that was a significant increase to -6.8 C at 5:30 AM, dropping afterwards back to -14 around 6 AM. Wasn’t present, but probably wind disturbance again.

Fifth day and night (21-22th September)

I was in Uyuni on this day where observed a partially cirrus covered sky, spotting a few undeveloped cumulus clouds over the mountains. From the diagram the conditions in the Alota area are still stable, this time the fast morning warming raised the temperature above 0 already around 7:45 AM.

The temperature curve of the fifth day and the following night

The curve follows a very similar pattern as in the previous days, reaching a little higher peak (19.5 degrees) shortly before 4 PM. Then comes the cleaner afternoon drop and the more disturbed evening and night. Reaching 0 degrees at 10:13 PM, the continuous negative values started from 11:11 PM. With a low of -11.7 C around 6 AM is still a cold morning, though less frigid than the past ones. Huge 34.1 degree daily amplitude, second biggest until now.

Sixth day and night (22-23th September)

I don’t remember the sky’s state on this day as was resting inside my hotel room most of the time (flu). The day part of the temperature curve is similar to the previous one, exceeding 0 degrees after 7:30 AM and reaching the peak of 19.9 at 2:45 PM.

The temperature curve of the sixth day and the following night

The night cooling is somewhat similar (more disturbed after the evening) but weaker, reaching only -6.8 degrees at 5:35 AM, preceded by some 3-5 degree ups and downs in shorter periods of time. First negative value appeared at 0:29 AM and became continuous from 1:37 AM. The 31.6 degree daily fluctuation is still solid.

Seventh day and night (23-24th September)

Except some more developed convective clouds above the mountains in the east the sky was still clear in Uyuni. It’s the warmest day of the research, the 0 degree mark was exceeded already around 7:15 AM, while the maximum climbed to 20.3 C at 1:17 PM.

The temperature curve of the seventh day and the following night

No significant changes in the curve’s general pattern, but the drop is even less potent this time, becoming continuously negative only from 4:49 AM and reaching a mild -5.4 C low at 6:15 AM. The 27.1 degree amplitude is less pronounced than in the previous days when it was constantly well above 30 degree.

Eighth day and night (24-25th September)

On this day I made a longer hike to Salar de Uyuni where the sky was clear, observing developed convective clouds only above the eastern mountains. However, now the air was a little dusty with less visibility than in the previous days.

The temperature curve of the eighth day and the following night

Again, no mentionable changes in the curve’s rising part, shortly after 7 AM reached 0 degrees and raised to 19.4 C at 1:09 PM following the general “convex pattern”. This was followed by the weakest night, the temperature becoming negative only from 5:35 AM and recording the warmest low of -4.1 degrees at 6:33 AM. This was preceded by more than 6 degree short term ups and downs, warming up to positive 9.4 degrees not long before midnight. Compared to the first days, the 24.8 degree amplitude is also modest.

Ninth day and night (25-26th September)

Another less memorable day regarding the ambience as was again mostly inside because of UV damage to my eyes (reflected rays on the saltpan), but I remember it was pretty bright in Uyuni, as it seriously disturbed my vision around midday.

The temperature curve of the ninth day (interrupted)

The graph shows the same clean and strong morning rise with the temperature passing over the 0 degree mark not long after 7 AM and reaching 19.0 degrees at 1:55 PM. But at 3:13 PM the diagram is suddenly interrupted. I concluded that the tripod was overturned in this afternoon by the violent westerly wind and the sensor’s cable was disconnected due to the fall.

Tenth day and night (26-27th September)

At dawn I went back to Alota by bus, where the morning was quite chilly, likely below -5 degrees. After the 20 km hike I reached the research spot before 11 AM. Fortunately the trouble caused by the wind was only temporary and the logger could continue recording the temperature after reconnecting the sensor. The day was completely clear (only some convective clouds in the far horizon above the southern mountains) but windy again in the early afternoon when I made an ascent to the peak of Jubina mountain.

The temperature curve of the tenth day (first part missing) and the following night

The day’s maximum was 19.1 degrees Celsius and was reached at 2:39 PM. I’m pretty sure that today the amplitude exceeded the 30 degree mark again, but having no concrete data from the night this is only an opinion. Nonetheless, I have data from the following one which was the coldest in the entire research period. The first freezing appeared around midnight, while the continuous negative values started from 0:37 AM. Despite being again less stable in the late evening and in the first part of the night when we can observe 3-4 degree short term ups and downs on the graph, the completely clear conditions favorized to descend very deep in the second part of the dark hours, reaching an impressive -19.0 degrees at 6:23 AM shortly before sunrise. This together with the previous day’s 19.1 degree maximum gives a staggering 38.1 degree amplitude in under 24 hours. The logger was stopped at 7:01 AM when the screen showed -11.6 degrees.

The average temperature of the 10 days research is 5.7 degrees Celsius. The mean minimum is -12.2 degrees, while the mean maximum 18.5 degrees, which give a mean daily amplitude of 30.7 degrees. We can observe that the mean temperature is clearly higher than we could expect solely from the minimums and maximums, which is caused by the fact that the positive part of the curve has a rounded peak, while the negative one is much sharper, technically V shaped.

General conclusions

  • The sky is predominantly clear both day and night, altocumulus lenticularis being the most common cloud type.
  • The wind follows an obvious pattern: in the night and morning is weak or calm, while the afternoon is much more windier, when the westerlies are dominating.
  • The daily temperature fluctuation is huge, usually exceeding 30 degrees, possibly producing one of the biggest average amplitudes on Earth.
  • The warming after sunrise is much faster than the cooling after sunset, regularly reaching or exceeding 10 degrees in one hour.
  • Regarding the finer details, interestingly the short period disturbances in the temperature’s course are always bigger in the evening and even in the night than in the late afternoon when the drop is much smoother, but it seems that this doesn’t correlates with the wind speed.
  • More than 1 degree fluctuations can appear often in very short periods of time even in the coldest, virtually windless mornings.
  • There is a clear difference between the positive (related to the maximums) and negative waves (related to the minimums) of the temperature curve, the former having a rounded, while the latter a more angled shape. That means the cooling is pretty constant until the morning without approaching an equilibrium state (very low humidity), thus, before sunrise is often 15, but sometimes even 20 degrees colder than around midnight.
  • Due to the elevation and the tropical setting the UV radiation is extremely high.
  • There is striking difference between sun and shade, without wind the same temperature feels much warmer than at sea level.

Comparing my logger’s results with the official data of the local weather stations

After finishing the research I managed to obtain valuable information at Uyuni airport meteorological station, thanks to the helping nature of the hotel staff. Below is a chart with the minimums, maximums and amplitudes registered in the same time period:

Comparison between the researched endorheic basin and Uyuni weather station (degrees in Celsius)

The most obvious thing is the huge discrepancy between the minimum temperatures, Laguna Seca being colder with 6 degrees on average and 8-10 degrees during the frostier days, while in the milder (less stable) ones they are pretty close to each other. There is no doubt that this is caused by the much stronger temperature inversion in the closed basin, which manifests itself during the calmer periods. Even if Uyuni too is situated on the floor of a basin, the more extensive flat terrain doesn’t permit the same level of cold air pool formation.

On the other hand, the highest temperatures are very similar on average, the closed basin being even slightly warmer despite the higher elevation, which under the same circumstances should gave him a disadvantage of around 2-2.5 degrees. This is probably caused by the stronger föhn effect in the Alota region, where the western mountain ranges are much closer and the dominant wind is blowing exactly from their direction.

Weather data of Bolivia’s official stations (Ogimet)
*Uyuni does not appear in this chart

The partially missing Ogimet data shows that Potosí weather station which is situated on the eastern part of the Altiplano and higher than Uyuni (above 3900 m) had 19-22 degree maximums in this period (likely föhn effect too), but also much weaker minimums (-3, 2 degrees) certainly due to the more exposed topography.

Regarding the amplitudes, thanks to the big advantage on the low temperature front, Laguna Seca exceeds Uyuni with a good 6 degrees, but sometimes the discrepancy can be more than 10 degrees. While Uyuni’s biggest amplitude in under 24 hours was 28.6 degrees (from 19.4 to -9.2 degrees) in the period of my research, the closed basin reached 38.1 degrees (from 19.1 to -19 degrees). No doubt that this place can surpass 40 degrees in the best circumstances. Taking into account that Uyuni has one of the biggest average daily fluctuations of all the official weather stations I’ve encountered until now on the net, a place which is regularly 5-10 degrees ahead of this definitely can be considered worth of studying in the long term. The future is open as always, we’ll see.

Aguita Brava volcano: Mars on Earth (3/3)

Interpretation of the logger’s graph

 

The temperature curve of the 7 day research period. I configured the device at home in Romania. Take therefore away 7 hours from the graph’s time to reach the bolivian local time. The 15:21 starting value means 8:21 AM

As I found the tripod with the instruments fallen over and partially buried under the snow on June 27, I had to found out when this happened. Analyzing the graph I noticed a remarkably elevated maximum temperature of 16.8 degrees Celsius in the early afternoon of June 22. That’s definitively an impossible value at these altitudes. The certitude regarding this conclusion is confirmed by the extreme fluctuation what happened shortly afterwards, when in a matter of a single hour the temperature dropped more than 14 degrees than rised again more than 10 degrees.

This would certainly not happen if the sensor was properly sheltered in the radiation shield. Here the sensor was over-exposed and the extreme temperature change must be caused by alternating windy and calm periods. So the fall over happened before. But when?

Closer view of the unrealistic high with the following dubious fluctuations (zoom in the image)

The first two days (when I was present in the region) are excluded. At the time the weather was fine, without even moderate wind. The temperature curve of this period is also realistic. Going a little ahead the things started to make sense. In the night of 21-22 the temperature was suspiciously high and constant (between -1 and -5 degrees). This can happen here only during very cloudy or windy weather (or both). And in the next day was the dubious 16.8 degrees maximum. Puzzle solved.
On the other hand in the last 4 days the maximums didn’t climbed above 0 degrees. This is probably because the sensor became snow covered. As the minimums of these days are quite low (approaching -20 degrees) and the temperature curves are looking regular I suppose the weather was again clear and not very windy (at least in the night).

After this short detective work let’s go back to the scientific evaluation. We have only 2 days to take in consideration as having valid datas:

June 20: This first day was the luckiest with both the lowest (-26.6 degrees Celsius) and highest (4.0 degrees Celsius) temperatures, respectively the biggest daily thermal amplitude (30.6 degrees).

The curve of the first day with the sharpest temperature rise (take away 7 hours to reach the bolivian local time)

During this interval happened a temperature rise of 12.7 degrees in 60 minutes and 6.7 degrees in 15 minutes.
Even if the weather station started its activity more than an hour after the astronomical sunrise, because the crater’s bottom was still in shade the inversion wasn’t affected before the sun reached the lowest elevations. This fact can be clearly seen in the graph, where the temperature remains almost uncheanched between 8:21 and 8:51. The minimum was registered at 8:36 AM.

The datas from the first hour of observation (take away 7 hours to reach the bolivian local time)

Then the temperature started to rise very fast and in less than 3 hours and a half climbed to +4 degrees, the maximum of the day. What’s interesting this happened pretty soon, just after midday. In the early afternoon the curve became close to an isotherma, remaining mainly around 2-2.5 degrees Celsius. In the latter part of the afternoon the temperature started to plummet and the vigorous fall continued during the evening hours. I was not present in the crater in this warmest period, but the extreme temperature rise was obvious also outside. It was absolutely no wind even at noon. A light breeze started after 1 PM. This explains why the maximum was registered at 12:16 PM.

June 21: The temperature dropped to -22.1 degrees Celsius in the morning at 7:46 AM. The sharp rise started again just before 9 AM and continued to the noon when reached 3.7 degrees, the days maximum. You can observe an outstanding upward curve during the first part of the night when the temperature rised from -16 to -5 degrees before starting to plummet again. It means even light winds can seriously disturb the night inversions in the basin. The amplitude for this day is 25.8 degrees, quite big, but significantly less than the first days’s 30.6 degrees. The night was clear again, but sometimes I noticed a light breeze at my camp (the same place, around 6 km’s from the crater). The near surface temperature was also less low than in the first night (more than 5 degrees milder). There were some cirrus clouds in the morning. I was present in the surroundings to around 3 PM and the weather was comparable with the day before: sunny, calm or light winds and quite warm for these elevations.

General conclusions

-If the weather is clear and calm the inversion layer in the crater is thick (filling completely the endorheic basin).
-During ideal conditions the lowest temperatures occur around 8-8:30 AM. The inversion is destroyed only well after the astronomical sunrise, when the sun reaches the bottom of the caldera.
-When is partial snow cover the head level air temperature above the snowy part is much closer to the ground level temperature above the uncovered part than to the snow surface temperature just below. The minimum temperatures above the snow surface are much lower than in the air above (up to 8-9 degrees difference).

-Because the first air movements usually start after midday the maximums are registered around noon when the heating of the ground is at peak levels.
-Clear skies are prevalent in the area during winter, but the calm conditions are much rarer. Strong winds (mainly westerly) blow often even at the crater’s bottom.
-The nights and mornings have more calm periods, the afternoon beeing the windiest part of the day.
-During windy weather the night minimums are significantly warmer (up to 20 degrees Celsius).
-The cooling period has a much longer curve than the warming period. The steepest parts of the graph are the ones just after the sun reaches the depression’s bottom, but it continues quite abrupt to the noon without major changes.
-The daily thermal amplitude can exceed 30 degrees, producing probably one of the biggest fluctuations in the entire world. *
-The minimums can go down well below -25 degrees (very likely also below -30 in certain conditions), lower than the current bolivian national record (-31 degrees Celsius) and maybe than any other official temperature measured between the tropics.

*The actual world record for the highest amplitude in 24 hours is more than 55 degrees Celsius and it was observed in Browning, Montana-USA. However this is a completely different kind of temperature change as the big difference was caused by a sudden change in the weather conditions and not by the pure physical potential of the local air.

 

Comparing my results with the local and global statistics

After the return to La Paz I visited the National Meteorological & Hydrological Service of Bolivia. There I found out some important datas:
-The lowest official temperature ever measured in a bolivian settlement is -25.7 degrees and it was registered in Uyuni (around 3700 meters elevation).
-The lowest official temperature ever measured in Bolivia is -31 degrees and it was registered at Laguna Colorada Weather Station in May 1992, close to the lake with the same name (around 4300 meters elevation).

The chart with the lunar/ annual minimums recorded at Laguna Colorada

-On 20 June 2018, when my logger recorded -26.6 in the crater of Aguita Brava volcano the minimum temperature in Uyuni was -9.4 degrees Celsius. Unfortunately they have no infos about Laguna Colorada for the same day. They only sometimes get datas from there. My guess is when those -25.7 and -31 degrees happened it was continuous snow cover in both locations. The difference between a -9.4 and a -25.7 degrees is enormous and can’t be explained otherwise, taking in consideration the weather was constantly clear and even windless on 20 June 2018.

The minimum and maximum temperatures in South America on June 20, 2018 with Potosi (Bolivia) having the biggest thermal amplitude : 27.1 degrees Celsius: from -10.5 to 16.6 degrees Celsius (source: Ogimet)

In the period of my staying it was no snow cover in Uyuni nor in any other place in the country situated below 4000 meters and the satellite datas showed the immediate surroundings of Laguna Colorada it was also free of snow. Definitely out of question to go even close to -31 degrees under these circumstances. During my visit the caldera was only partially snow covered and still went down to -26.6 degrees Celsius and close to the snow surface even much lower (-35 degrees). Interestingly the temperature close to the uncovered surface was about the same as the air at head level above the snow. I have no doubt if the same atmospheric conditions are present and there is continuous snow cover in the crater the minimum would go well below -30 degrees, surpassing the lowest official bolivian temperature.

 

Coldest place between the tropics?

To my knowledge beside Laguna Colorada there is a single place situated on tropical latitudes where the temperature plummeted below -30 degrees. It’s Ollagüe in Chile with -37 degrees Celsius. This is the lowest temperature measured between the tropics what I found on the net. Ollagüe settlement is situated right on the border with Bolivia, but it is also a high volcano named Ollagüe nearby. The village’s elevation is similar with Uyuni’s and much lower than Laguna Colorada’s, so a -37 degrees there is a little dubious for me. Maybe it was registered somewhere on the volcano? Is this data reliable at all? Maybe it was only -27? It looks much more realistic for a place situated at 3700 meters elevation at these latitudes. However, until solid facts reveal the truth this remains an open question.

In my opinion the crater of Aguita Brava is a strong canditate for both the titles “the tropical pole of cold” and “the pole of diurnal thermal amplitudes”.

 

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Aguita Brava volcano: Mars on Earth (2/3)

                      Journey photo album

 

Rough start with one full day delay. At Miami airport

 

My hotel room in La Paz . Pretty cool, but clean and has good hot shower

 

Basilica of San Francisco, one of the most emblematic buildings of the capital (16th century)

 

The center

 

Visiting Tiwanaku pre-columbian archeological site the next day: The “Gate of the Sun”

 

Another famous statue of the religious complex

 

It’s easy to make new friends here  🙂

 

Huayna Potosi (6088 m) seen from the road back to El Alto

 

Descending to the city center with an aerial cable car (the cheapest and fastest method)

 

La Paz: Crowded traffic with lots of street vendors on both sides

 

Arriving in Uyuni (hostel)

 

Starting from Uyuni with a private driver to the south-western alpine desert, where my target is located. There are daily flights from the capital. Uyuni is a prosperous touristic center, all because of the nearby Salar de Uyuni, the biggest salt flat in the world (more than 10.000 square km’s, over 140 km’s in diameter)

 

San Cristobal silver mine

 

Villa Alota village

 

Climbing higher and higher. I start to feel dizzy

 

At over 4600 meters it is obvious: I’m not well acclimated…

 

Snowy peaks on the chilean border

 

Approaching the Eduardo Avaroa National Park. You need to buy an entrance fee here

 

Straight towards my target

 

The final part became more wintry, but still manageable without any technical difficulties. We are approaching 4900 meters elevation

 

I start the journey by foot around 1:30 PM from near the fumaroles and hot muds of the Sol de Manana complex. Some tourists are present at the bigger geysers. The weather is quite windy and felt much colder than at the lower elevations

 

First time above 5000 meters. I’m in good shape but the backpack feels heavy at these altitudes. The breathing is difficult. From here I can see Aguita Brava volcano in front of me

 

Tired, around 5 PM I set my camp on the barren plateau. No tent, only a bivy sack and a good sleeping bag. My survival strategy is to shelter from the westerly winds behind a big boulder

 

Below -20 degrees on the ground beside me. The night is clear and surprisingly even windless. The Milky Way looks completely different from these heights. It is more similar to the nebulas seen on Discovery or National Geographic. After some hours of strong headache and nausea I start to feel better and decide to climb the mountain in the dark to reach the crater’s bottom before sunrise. I leave the unnecesary things here, securing the bivy sack with nearby rocks and at 4 AM I’m heading to the volcano

 

The main peak was farther than I thought. The sunrise found me struggling on the ridge. But the view is awesome!

 

Finally at 5500 meters on the top of Aguita Brava. No wind even here, I feel very lucky

 

First view of the crater. The lowest part still in shade. What? A lake? I didn’t expected this. The place is completely dry on GoogleEarth

 

While descending in the caldera I suddenly feel how the cold is intensifying. It means the inversion layer is thick, filling the entire endorheic part of the basin. Okay, it’s no water nor ice at the bottom, only a dry lakebed. But a strange thin mist was present on the lowermost layer. Probably this tricked me. First I thought it is something related to the volcanic activity like the fumaroles at Sol de Manana

 

I do a quick near surface measurement with the electronic precision device. Wow! That’s really impressive for a tropical latitude!

 

The alcohol thermometer shows even lower values. It seems I’m not late. Here the night is not over. The mist must be caused by the strong inversion. I know the air is extremely dry on the Altiplano in the wintertime, but here on the bottom, close to the ground probably contains much more water vapour

 

In a couple of minutes the weather station started its activity. The snow mound is where I buried the logger to protect it from the extreme cold. The sensor can measure down to -40 degrees, but the logger itself is functional only to -30

 

It was difficult. But the project is on track

 

As the sun reached the lowest parts, after only a couple of minutes became considerable warmer in the crater

 

My self-designed talisman at the bottom of Aguita Brava caldera

 

Juriques volcano (5704 m) in the background

 

Putana (5890 m), the smoking volcano (sulphur dioxide) is another major peak on the chilean border

 

The plant living at the highest altitudes (around 5200 meters)

 

At noon became surprisingly warm. Still no wind, my face is burning. As the water in the thermos is lessening I compensate the fluid loss by eating small ammounts of snow. Dehydration is a serious danger at high altitudes

 

Around 2 PM, back to the camp. The other thermos waits for me here

 

Exhausted but very content. I go to sleep early today

 

Next morning. Doesn’t slept much, but the long rest was certainly helping

 

Approaching Sol de Manana geysers

 

Nobody is here now, I can enjoy the nature’s spectacle in solitude

 

Primordial landscape. The battle between cold and heat

 

After reaching the main road, I was waiting for the trucks which are coming from the Apacheta mine. Non of them appeared, but I had luck with a jeep coming from the geysers

 

At Polques hot springs. The driver will take some tourists to the border than he will pick me up here and we will reach Uyuni in the evening

 

Local bird hunting in the shallow water

 

Laguna Chalviri (around 4400 meters elevation)

 

Yeah, here the winter UV is stronger than at home the summer version. By the way: today I’m turning 40…

 

Uturunku, the highest peak in southern Bolivia. On the way back to Uyuni

 

Two days later I take a local bus (very cheap) to cross the famous Salar de Uyuni. Close to the shore is puddly, but after that is only dry salt pan as far as you can see

 

Short stop at Incahuasi island in the middle of the salar

 

The bus has elevated bottom, probably to can handle the puddles close to the shore

 

Almost 150 km’s of pure whiteness. We are heading to Llica settlement on the other side of the salar

 

From the village (background) I will go to a lesser known but very interesting geological structure: the Hoyada Ulo meteor crater

 

I had the crater’s coordinates on my GPS, but didn’t really know which way is the best. It ‘s around 7-8 km’s in straight line. Meanwhile the landscape became “western-like”

 

I reach the high plato around sunset. Feeling some presence of indian spirits I continue the hike until dark

 

Next day at dawn I’m on the rim of the crater. Surpisingly mild +1 degree Celsius here at head level.  (I know. This picture looks like a movie screenshot from the 60′ 🙂

 

But I measure -14 degrees on the bottom. Nice inversion.

 

A smaller salar. Partially frozen now

 

That’s water there. Very salty, therefore still liquid at these temperatures

 

After the sun appears the season changes to spring. I decide to climb to the highest ledge

 

Definitely worth the effort! Salar de Coipasa, another huge salt flat can be seen in the background

 

A condor is patrolling above his empire

 

The weird “viscacha” is like a hybrid between a marmot, a squirrel and a rabbit

 

No way. I must turn back. Meanwhile became quite warm

 

When returning I found llamas on the bottom. Very peaceful animals, like bolivian people in general. No need for shepherd dogs, as the bigger predators are rare on the Altiplano. Pumas are said to live “everywhere”, but the reality is they are in small numbers for the huge territory. Meanwhile the temperature climbed to +16 degrees. Remember the -14 from the morning? That means a 30 degrees daily amplitude!

 

Before complete dark I reach Llica. It was a long day. I think the coca leaves helped me 😉

 

Rising more than 1600 meters above the flat landscape, Volcan Tunupa (5321 m) is the biggest landmark in the middle of the salt desert. On the car back to Uyuni

 

The bus is creating waves on the waters close to the shoreline

 

Two days later I start the second (and last) trip to Aguita Brava. As now the full tourist circuit is open the approache is much cheaper. I travel with two french who are heading to Chile. I think french are the most common tourists in Bolivia

 

Reaching Villa Mar settlement in the late afternoon. After sleeping in the village we continue the journey to the high plateau the next morning

 

This snow wasn’t there the other day. Certainly the wind is responsible for this change. We must turn back a little to take the smaller road

 

Before 8 AM I leave the car. It is windy and the -8 degrees feels much colder. My plan is to climb the mountain today and descend to the other side tomorrow

 

The wind intensifies, the sun has no warming effect in these circumstances. It’s ironic how similar the pictures can be while representing completely different realities

 

In the first part I felt markedly stronger than the other time but above 5100 meters the walking/ breathing became harder and harder. The last 100-200 meters was a complete struggle. I thought after 2 weeks at 3500-4000 meters I can handle these heights without any problems. But it was far from truth. The 1400-1500 meter ascent in 7 hours was too much

 

I left the unnecessary luggage on the rim of the crater. The westerly wind was very strong here, blowing straight in my face while I started the descend into the caldera

 

Oh, no… After this extreme struggle I found the weather station on the bottom fallen over. I underestimated the local weather conditions trusting the crater’s “sheltering effect”. But the gales were present even here. Even now is present! Luckily non of the instruments were damaged and I managed to collect everything. I also checked the logger’s daily statistics and found out the best day was the first when the temperature climbed from -26.6 degrees to +4 degrees Celsius

 

The steep climb on the friable volcanic debris back to the rim was somehow less strenuous than I was expecting after the former difficulties. My guess is that after the organism is over the highest part and starts descending again it recovers (partially). Therefore a new climb will be less hard as you have already visited the former height before. I understand the logic and also knew the theory, but I’m surprized because of the contrasts and because of the short time you need for these changes. After packing full my backpack again I started to descend the mountain on the otherside

 

No real altitude sickness from now on, but I was definitely exhausted when reaching this boulder where I set the same kind of camp (around 5000 meters elevation). Now the protection has real meaning as the westerly is still blowing. It was a very hard day. Time to sleep

 

Next morning I’m heading to the Dali Desert, where the main road is passing. The night was alternately windy, with some calm intervals between. It was nice full moon and in a certain time the bright disk was positioned exactly above my head. I mean vertically

 

The surreal Cerro Amarillo (5661 m)

 

The wind became even stronger while I reached the road, but the lower elevation and higher sun angle takes away from the cold. After a new bath at Polques (where I met 2 other hungarians) a jeep taked me back to Uyuni. The same reasonable price again

 

The main plaza in Uyuni. The small town is a tourist magnet. There is little to see in the settlement itself, everything is about the salar. The small center area is crowded with hostels, tourism offices and restaurants

 

And of course: souvenir shops

 

Tours and tours and tours… Sharp contrast between the small, modest brick buildings and the big, colored buses and modern jeeps

 

Many street dogs, but they are all harmless. In Bolivia the quadrupeds are surprisingly gentle

 

Pique macho, a traditional bolivian dish. Not really a delicacy, but good when hungry. Or just to tease the many scandinavian feminists  😉

 

In the same evening I’m back to La Paz. The plane took off 20 minutes…earlier. Never seen such a thing in my life. I was very surprised how easy is to travel in Bolivia. Maybe too easy?

 

Plaza Murillo, one of the main meeting places of the capital

 

Mercado a Las Brujas (Witches Market), another tourist hotspot of the center area. Beside the many colored clothes and wallets you can found here all kinds of weird things like various medicinal plants and even dried llama fetuses

 

The next day I visit the National Weather Service’s office and found out some important infos (see in part 3)

 

As tomorrow in the morning I will start my journey back to Europe I will use this day to see more of the city. Heading down to the lower elevations

 

There are many cable car lines, all colored differently

 

The richer part of the city

 

In the afternoon I climbed a precipitous hill situated in the outskirts. It was quite difficult because of the friable rocks, also uncomfortable, as many cactuses grow on the steep sides

 

I have no time for the highest peak, the relief is too fragmented from this side

 

The high Andes at sunrise from the plane. Bye lack of oxygen!

 

To be continued…

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Aguita Brava volcano: Mars on Earth (1/3)

Intro: The highest capital city

Bolivia is situated in the Southern Hemisphere on tropical latitudes, but it’s western part’s high elevation make the closure to the Equator no more than pure statistics. With around 3600 meters altitude in the center area, La Paz is the world’s most elevated capital city. Contrary to the usual setting, here the airport is situated well above the city itself, therefore at 4000 meters elevation the air in El Alto (spanish for “The Heights”) is even thinner. The explanation is the local topography: La Paz is sheltered in a deep canyon, below the wind-swept Altiplano (“High Plateau”) where the flatter terrain is more suitable for an airport.
If somebody came here from normal elevations he/ she certainly will feel some signs of the “mountain sickness” in just a couple of hours. This include headache, nausea, dizziness, tinglings in the limbs and shortness of breath. The last one is very obvious while doing some effort, like climbing the steeper streets of the city. As the urban agglomeration has a very complicated relief you have a lot of inclined terrain to deal with. Better take it easy in the first days. However, some people acclimatize much easier than others. It’s more a genetic thing than something related to physical fitness.
Another interesting fact regarding the local climate are the big daily thermal fluctuations. This is the most outstanding in the dry season, which here coincides with the (austral) winter months. From June to August the temperature tipically fluctuates from near freezing in the night/ morning to 15-20 degrees Celsius in the early afternoon hours. But, because of the high UV radiation the daytime temperatures felt much warmer. A 17-18 degrees Celsius in the sun here on the Altiplano is more like a 25 degrees at sea level. Really sharp contrast between the sun and shade. The sky is normally clear or partially covered with higher clouds, the possibility for any kind of precipitation is pretty low in the winter months.
Despite the lack of oxygen the streets of La Paz and the neighbouring El Alto are very crowded. From food to clothes and car parts, everybody is selling something. The traffic can be incredibly slow, but the locals are very patient and peaceful. Conflicts between the citizens are rare. Tourism is one of the main income in this poor, landlocked south-american country, so you will see lots of backpackers wandering in the center area.

View of La Paz with Illimani mountain (6439 m) in the background

 

Choosing the target

Everybody heard about the expressions “lunar”, respectively “martian landscape”. It refers to a very dry and barren place, usually a desert, where no vegetation is present and the terrain is mostly made of by bare rocks and/ or clay.  It is also known that because of the lack of an atmosphere the climate of the Moon and the Mars is very severe, fluctuating between extreme cold in the night and blistering heat in the daytime. This is mostly because of the lack of water vapour in the air, whose presence regulate/ moderate the heat transfer on Earth’s surface. However there are some places on our planet where the climatic conditions remind of these dead celestial bodies, presenting huge daily temperature fluctuations. Where are they and which parameters are responsible for the most extreme conditions on Earth?

First you need clear skies. Clouds are composed of water vapour, which keeps the heat trapped in the lower atmospheric layers. Deserts are known to have less cloudy days than any other ecosystems. Second you need high altitudes. The thinner the atmosphere, the less heat can be kept inside during the nights and more solar radiation will reach the surface during daytime. So high elevation deserts are better suited than the ones situated near sea level*. Thirdly you need high solar angle to have even greater differences between day and nightime conditions. It means high elevation tropical deserts are the best choice. And fourthly you need concave topography, because it heats more in the daytime (reradiation from the sides) and cools more in the night hours (collecting the denser, colder air like a bowl). The theory is ready, let’s check the practical availabilities.

 

How about the Altiplano? It is dry, it is very high, it is situated on tropical latitudes and there are many non-active volcanoes with well preserved, deep craters. All the four conditions matches. Reliable climatic statistics of the region are pretty scarse on the Internet. On wordclimate.com I’ve found La Quiaca weather station on the Argentina-Bolivia border (around 3400 meters elevation) to have the biggest average daily amplitude. Here in June and July the temperature fluctuates between -7 and +15 degrees. Regarding the precipitations the western part of the high plateau is even drier, so I suppose the thermal amplitudes can be even greater in the region situated around the triple border between Argentina, Bolivia and Chile, known as “Puna de Atacama”.
One of the biggest astronomical observatories in the world have been built on the chilean side of the Atacama Plateau. Why? Because the region offers one of the clearest skies on Earth, year round. It is said the air here has comparable transparence with the one above the South Pole. After studying the local conditions from the weather statistics of the ALMA observatory I’ve concluded the biggest drawback of the regions climate is the wind. Air movements are mixing the layers, destroying the forming inversions in the nightime and cooling the ground in the daytime. Beside its dryness, the winter is also pretty windy on the Altiplano. So, apart from the already mentioned four, I will need also a fifth parameter: Luck.

The relief of Bolivia with the black dot on the south-west marking the location of the Aguita Brava volcano

But where exactly can be the place with the highest daily thermal amplitude? After stopping at Juriques volcano on the Chile-Bolivia border, finally I decided to choose a lesser known crater situated a little more to the north on the bolivian side. The mountain is named “Aguita Brava”. The location is marked only on good topographical maps. The barren volcano is close to 5500 meters high with a crater of around 800 meters wide and 80 meters deep. The bottom of the caldera is situated at 5320 meters elevation. Because this mountain has a somewhat less prominent topography than Juriques, which rises abruptly above the Atacama desert with little protection from the dominant, westerly winds, I presume Aguita Brava crater has better chances to produce good night-time inversions. The caldera itself is also a little more sheltered inside the volcano, with slightly lower, but still enough good sky view factor (around 0.91-0.92, according to my calculations on Google Earth).

Close-up of the caldera with the 10 meter contour lines calculated on GoogleEarth

Winter is the dry season here, it means more clear skies and greater chances to have huge daily amplitudes. Even if rare, but snowfall is possible during the colder months too. In the frigid and bone-dry conditions the snow doesn’t melt, but sublimates (transforms directly from the solid to the gas phase). Under the strong sun the white blanket wanishes rapidly, however the wind collects the snow in the sheltered areas, often blocking parts of the roads on the high plateau. Timing: second part of June.

Access to the volcano: There are only a few roads in this remote area and none of them is paved. Despite the place is almost uninhabited I found out there are some touristic circuits, which approaches my target pretty well. Around 10 km’s to the north of the crater is an attraction composed of many small geysers named “Sol de Manana”. This place is situated close to the highest part of the Uyuni-San Pedro de Atacama (Bolivia-Chile) road, and when the conditions permits (no snow blockages) has daily visitors year round. The geysers are situated above 4800 meters elevation, only 600-700 meters below my chosen mountain. Properly acclimated this means a one day hike, though with a heavy backpack can probably be quite exhausting.

Russian topographic map of the volcanic plateau on the Bolivia-Chile border (the arrow pointing to the chosen crater)

Aguita Brava is situated inside the Eduardo Avaroa Andean Fauna National Reserve, a protected area with many bird species, including flamingoes. These can survive in the harsh conditions thanks to the salt lakes like the reddish Laguna Colorada, where they eat the alges. Laguna Verde is another local attraction, but this lake supports no life, because of the arsenic content. The green color is given by the copper minerals and is more intense during windy weather. Licancabur volcano rises above the surreal lake, where the highest level of UV radiation on Earth (43.3) has been measured. Though this was registered during the summer, because of the tropical latitudes the sun has a pretty high angle even during midwinter and the clear skies – thin atmosphere combination gives a solid recipe for sunburn if unprotected.

*The rumour about the Sahara to have freezing temperatures during the nights and up to 50 degrees in the daytime during a single day is a very prevalent false myth on the net and school books too, actually probably a misunderstanding. The truth is in the winter nights the temperature can go sometimes below 0 degrees and in the hottest summer afternoons can approach 50 degrees. But when there is freezing in the night, the daytime highs will probably reach around 20 degrees and when the afternoon heat is close to 50 degrees, it is unlikely to cool down below 20-25 degrees in the following night.

 

Brief summary of the research

My plane landed in El Alto on June 16 in the morning. I spent only 2 days in La Paz before taking the domestic flight to Uyuni. Because of a recent snowfall in the high Andes the usual touristic circuits were not fully open and the approach to the geysers area in the next days (my starting point) was questioned. The company that I contacted from home gave me a private driver to take me nearby the fumaroles in a single day. Though the road was partially snow covered in the last quarter, but we managed to get very close to Sol de Manana without any problems.

View of the Bolivia-Chile border from 5500 meters elevation

From this place (4850 meters elevation) I left the car and started the slow hike up the mountain (10-12 km farther to the south). I set up my camp in the afternoon on the volcanic plateau slightly below 5000 meters altitude. No tent, only bivy sack + sleeping bag, sheltered behind a boulder. I was battling mountain sickness, but the weather conditions were very good (clear skies and no wind) during the night. Feeling better I climbed the mountain in the dark. Before the sun reached the bottom of the caldera I was there and soon the mini weather station started his activity (June 20, before 8:30 AM). The coordinates of the study area are: 22.30.762′ S, 67.47.744′ W, the altitude is around 5320 meters.

The crater of Aguita Brava volcano

The logger’s sensor was set inside the helical radiation shield (donated by Barani Design Technologies) around 170 cm height, mounted on the top of a photo camera tripod. The logger itself was packed in a plastic bag and sheltered under the snow to protect it from the extreme cold in the night. The device recorded a temperature value every 5 minutes from the time it was started. I left there also an alcohol minimum thermometer to measure the lowest temperature of the entire research period (mostly for the case if the logger will have some trouble). A precision electronic device was used for instant measurements.

The weather station at the bottom of the caldera

I collected the equipment 7 days later (June 27, around 1 PM), when unfortunately I found the tripod with the devices fallen over and partially buried under the snow.
During the research period the sky was generally clear or partially covered by higher clouds, but some of the days were very windy. The first day was my lucky strike, when I had perfect conditions for strong inversions and extreme daily amplitudes. After the second day the weather became more unstable (but without new snowfall) and (concluding from the logger’s graph) probably during the following night the tripod fell down. On 27 at midday when I collected the equipment it was strong gale on the crater’s rim and surprisingly even at the bottom.

My camp in the martian landscape

The caldera was partially covered by snow during both visits, the ratio between the covered and uncovered parts was around fifty-fifty. The snow below the tripod was 20-25 cm deep, but just a few meters farther it was completely missing.

The lowest temperature registered by the logger during the one week research period was -26.6 degrees Celsius, the highest (reliable) +4 degrees Celsius, giving also the biggest daily thermal
amplitude : 30.6 degrees. Close to the snow surface I recorded -34.3 degrees with the precision electronic device (instant measurement) and below -35 with the alcohol minimum thermometer.

I spent 3 nights on the mountain, two nights on the first research trip (same camp between the geysers and the peak twice) and one night on the last one (on the other side of the crater at similar 5000 meters elevation on the volcanic plateau), visiting the caldera only two times (first in the morning of June 20 and finally in the early afternoon of June 27). The days between I spent in a hostel in Uyuni settlement and on the other side of the Salar de Uyuni, around 250-300 km’s to the north.

Vicunas (the wild ancestors of llamas) on the high plateau

There are no settlements in the area, only a mine some km’s farther on the road from the geysers. The crater is completely lifeless, but the highest plants (small yellow patches) can reach around 5200 meters elevation on the slopes of the volcano. I’ve also spotted some seagull-like birds above my camp and vicunas not far from the fumaroles.

 

The instruments used in the field

-One LogTag Tred30-7R data logger with the measuring range between -40 and +99 degrees Celsius, an accuracy of 0.5 degrees Celsius and a resolution of 0.1 degrees Celsius.
-One Greisinger GMH 2710-T digital precision thermometer with the measuring range between -199.9, +200 degrees Celsius, an accuracy of +-0.1 degrees Celsius and a resolution of 0.1 degrees Celsius.
-One meteorological alcohol minimum thermometer, USSR, 1988, with the measuring range between -50, +40 degrees Celsius (the first dash corresponds to -52.5 degrees).
-One photo camera tripod serving as the support for the instruments.
-One helical solar radiation shield from Barani Design Technologies: https://www.baranidesign.com/

The Barani helical radiaton shield at 5320 meters elevation

 

To be continued…