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I guess it depends on your location and your interest at the time. I don’t remember contrails growing up in the 50s in Bucharest, Romania. Now I’m in New York, where I see A LOT of them. The air traffic has increased tremendously since the 50s everywhere and the aircraft changed.
I suppose people remember that after September 11, 2001, the air traffic was stopped completely over the US. That provided an opportunity to study the effect of contrails. Here is an article about that event, which raises some interesting, perhaps controversial, issues:
http://www.greenmedinfo.com/blog/artificial-weather-revealed-post-9-11-flight-groundings
From the esthetic standpoint, I have mixed feelings about contrails. Sometimes they are beautiful, other times they can be just “noise”.
I thought I’d share this picture because of the several things happening at once.
There is fallstreak hole on the left.
Then there is a contrail going across, slowly ascending from mid left to mid right where it’s very bright as it gets closer to the Sun. On the left side, over the altocumulus layer, it’s probably just the contrail shadow. And just above it there is a fine line of dots that I believe to be Crow instability. (Maybe I’m wrong, I learned about this effect from this thread. But see the enlarged shot.)
Finally, on the right bottom corner there is what seems to be some virga that looks like brush strokes.
The sky has been generous this morning, unfortunately I was in a hurry and the iPhone camera can only pick up so much.
Hi Samuel, I am also a relatively new joiner, since last August. The rarest is the cloud or optical phenomenon that you cannot see in your area. For me, at 40 degrees of latitude, that would be the stratospheric clouds. But if you are way up north, that may be a funnel cloud. (Though a quick google search shows there are tornadoes in Norway.)
I have the CloudSpoter app on my phone and I am still hunting for fog. It’s been very dry here. Not that I have never seen fog…
So, really, why are you asking? Is this like asking what’s the highest peak? The journey is the reward, keep looking and you will see wonderful, rare, possibly strange things.
Infrared lies on the spectrum below red, so we humans don’t see it. Whatever is captured by the sensor needs to be shifted into colors that we can see (transposed like a musical piece written for a baritone when a tenor would want to sing it). Black and white is a bit different, in that, just like with visible light, colors disappear and only the intensity of the light is captured.
Anyway, there are two situations. If there is sunlight (which contains infrared), what you capture is the reflection of that light by the clouds (or other objects). The clouds do radiate some infrared, but what comes from the Sun is so much more intense. What makes those pictures so sharp is the fact that the infrared light is scattered very little, even less than the red light.
If there is no sunlight, then what the infrared sensitive film or sensor captures is the radiation emitted by bodies, the hotter, the brighter. Police and military uses come to mind, for instance a person hiding in the dark becomes a bright target when looked at with IR goggles.
IR cloud cover pictures taken by satellites reveal the cloud temperature. The tops are cold so one can tell how high the clouds are.
Michael, what a great catch! I wanted to ask you something. You say “during a morning” patrol, how early in the morning? I am interested in the approximate height of the sun at the time.
Hygge, thanks for the article. Although The Times only shows me the first two paragraphs, I read about the plan in the Wall Street Journal. My thought, as a hiker, was, I wish they did not build one, but if they do, I may want to stay there.
Experimenting with Chrome in incognito mode, so that Facebook does not see my cookies and recognizes me, I think I reproduced the problem you ran into and there may be a solution. When the pop-up asks you to join, click “not now”. It will go away and you will see the photo. Now if you click on it, it will expand. You can further move the mouse cursor to either side edge and little right or left arrows will appear. You can now go from one posting to the next or previous.
Welcome, Barbara! You should be able to observe some nice storm clouds in NE, hopefully safely. (I am in New York City.)
Hygge, Bear Mountain is a state park. It’s just south of West Point, NY. If you follow the Hudson river, you will see Bear Mountain on the west side of the river. The highest peaks are about 1200-1300 ft (with the Hudson practically at sea level). By contrast, the Catskills highest peaks are over 4000 ft, which allows them to make their own weather, as one would say. More interesting clouds in the Catskills.
Hygge, my shot was from Bear Mountain. There would be another 50-60 miles to the Catskills southern edge. Here is a picture from the Catskills from a while back. I guess the color of the leafless woods and the rounded hills look similar indeed.
