I love the Sahara. I spent one night in the desert and I will never forget it. The stars were amazing. The moon didn't rise until ~midnight. When it did finally rise, I got really confused because I hadn't noticed it missing. At first I thought the sun was rising. I layed on the dunes so long I could watch the stars rotate in the sky.
When the sand falls on the snow in the Alps, it increases the ability of the snow to absorb heat from the sun (because it's darker -- this is known as "albedo") which accelerates the melting of the snow. This happens in the Western United States too, and has been studied [0] as a source of uncertainty in predicting snow melt timing (e.g. for things like water availability).
Funny, I went through Raytracing In One Weekend[0] recently and encountered the word "albedo" there for the first time in my life. Since then I feel like I've read it or heard it nearly every day! Anyway, thanks for being today's "albedo" guy :-D
As a former competitive alpine ski racer, that effect plus the abrasion of the sand itself would make for some very interesting wax choices. “Wetter” usually means a softer wax, but softer waxes don’t stand up to abrasion like that. I’d be interested where the majority of the sand ends up on a mountain and how it gets distributed through the snowpack when groomed out.
Also soot that decreases the albedo of snow. On a smaller scale this effect is also readily visible in just about any city that gets snowfall, especially in the spring!
This is very accurate. I spent 10 months in the Saudi Arabian desert as a young airman during Desert Storm in '90-'91. I experienced 3 or 4 sand storms and the enormity of them overwhelmed everything with an orange/tan/yellow hue. I also witnessed sandstorms wear down paint on vehicles to shiny bare metal!!
Wow, it reaches Poland? I can only imagine what a volcano or an asteroid would cause. I still remember the April 2010 when the Eyjafjallajökull volcano erupted in Iceland causing 100k flight cancellations and a very rainy summer.
That’s why we’re so fucked if we ever manage to break global weather in such a way that sand doesn’t go from the Sahara to the rest of the world anymore.
Richard Hammond did a pop-science series about the weather and it talked about how dust from deserts can move very far. It's an interesting watch: https://youtu.be/DeYvP2A3QvU&t=8m20s
The dust particles bounce against one another and propel some of the particles higher and higher up into the atmosphere. Then the winds can carry them very far.
January 2020 in New Zealand we had smoke that block out the sky, making everything a weird red hue. The smoke travelled from Australia, 2645km away ( roughly the same as London to Algeria. I was amazed that the smoke could travel that far without dropping off.
It happens relatively often here in the French Pyrenees (it may double down as a Foehn effect going from South to North after passing the ridge line (which is horizontal on a map). If you pay attention, you may notice the result in one James Bond from the Pierce Brosnan era "Tomorrow never dies"; the opening (or second?) scene is supposed to take place in a rogue airbase in Somewheristan, but it was actually shot in an altitude airport in the French Pyrenees, just a day or two after one of those Sahara sand winds.
But this time, it was not just a fine dust. There is plenty glued on the house windows, and shutters, and walls. It was raining mud :-D Never seen that in over 40 years.
Switzerland here, I agree. When I looked out the window after waking up it looked surreal and scary.
I tried taking a picture with my phone, but sadly it didn't turn out orange at all.
Not having noticed this phenom before, I was quite worried and sent out some panic filled voice messages. Thankfully a friend pointed me to SRF meteo where it was explained.
Judging by the top post of r/switzerland "Why is the sky orange" I wasn't the only one.
Ufa, Southern Urals, Russia here. Guess what happened on the other end of that? An arctic breeze with snowstorm and a 20°C temperature drop over night.
Zurich here. I noticed something is off after waking up. The light seemed.. Dirty? Went online to check what was happening. Strongly dislike this weather phenomenon.
My experience with Sahara dust was crossing the Atlantic. It was a fine powder that coated the white gelcoat of our boat. Mixed with salt spray it turned into a grease. And just coated everything. By the time we arrived in Barbados we had more slip and falls than I would normally expect.
It was quite interesting to see the effects of the Sahara sands. Like our eyes recalibrated the color white until we washed the boat and snapped us back into reality.
Also, some parts of switzerland are geography more south Europe than others,: depending on which side of the Alps you are, things can be quite different climatically. I grew up in Ticino; for all intents and purposes climatically it's like the rest of northern italy.
Milano is at almost exactly the same latitude as Trieste. Perhaps you're trying to make some point that Trieste is on the adriatic sea so it feels more like southern europe.
My point was not climatic though, but as we were talking about sand dust carried by the wind, the presence of Alps makes definitely a bigger difference than 50km (the south-north distance from the line Trieste-Milano to the swiss border).
The same Alps are what make Ticino climatically quite diatinct from the northern part of switzerland (the mountains affecting climate)
Yesterday I had fun exchanging pictures with friends we all shoot ourselves. They all looked like sepia filtered but weren't edited.
After some time outside you don't see the orange-brown hue anymore. But when driving all lights of oncoming car lights seemed blue. Even the white digits of my car's speedometer glowed with a strong blue hue.
My wife said that she felt like hell and apocalypse. I felt similarly opressed and even looked up teletext.ch whether a giant volcano erupted somewhere or not.
It's not the first time we experienced Sahara dust, but yesterday it was extremely strong and unusual for being it in winter.
Used to get Saharan dust in Puerto Rico (when I lived there). Thin layer of black dust throughout the apartment that had to be cleaned every 4 days or so.
I know Saharan dust does reach Puerto Rico but after looking up the soot theory, it seems more plausible. I even found two local articles in Spanish about it (soot).
