Cumulo-a-Palooza!

Guess how high these low clouds are? 

  The lowliness of cumulus clouds is easier to recognize if there are mid-level clouds in the same sky. Take yesterday. The sky was full of smallish cumulus clouds--the puffy ones with gray shading in the photographs I have posted here--and, above them, patches of clouds that were clearly floating above them.

  The cumulus clouds rest at altitudes ranging from ground level to about 6,500 feet. I cannot estimate the height of other clouds. "Low" works fine for me.

  The higher clouds are a type of mid-level cloud known as altocumulus. (Yes, "alto" means "high," but meteorologically it means "mid"). Altocumulus clouds are found at altitudes ranging from 6,500 to 18,000 feet. "Mid-level" works for me. I will explain why at the end of this posting.

  I have zoomed in on the clouds here--take a look so you can get a better look at the two levels--the large gray and white cumulus below and the smaller, fleecy altocumulus above.

Cumulus below, revealing patch of altocumulus above.

Here they are again, even closer so you don't have to find your reading glasses.

 A heart-shaped cumulus cloud! It must have noticed me staring.

   It always takes my eyes and brain a while to see the depth of the sky, to see that what I might initially describe as "behind" is actually "above," to see the sky not as a celestial dome but a celestial sandwich. From our perspective on earth, the land we stand on is flat and the sky is flat. We cannot observe the curve of the earth nor the curve of the atmosphere that surrounds it. We do not live in a snow globe.

  Take a look at the photo below. These are cumulus clouds--cumulus humilis because they are wider than they are tall. The bases of all of these clouds--from the top right of the photo all the way back to the horizon point in the lower center of the photo--are resting at the same altitude. All of these clouds are the same height.

Flat flat flat.

    Look again after reading this: as your eye moves from upper right to lower center, do not let the clouds sink down toward the earth. Keep their bases up there at the same level. Do not let the clouds and the earth touch at the horizon. You're getting it if you feel your eyes and brain arguing.

   Now, for the reason I have not yet mastered estimating cloud heights. I don't own a gizmo such as a lidar detector or a ceilometer (below).

This ceilometer is used by the Atmospheric Radiation Measurement Program of the U.S. Department of Energy. 

Photo source: http://www.arm.gov/instruments/vceil

 And because knowing the height of cumulus clouds involves a formula that requires subtracting the dew-point temperature from the surface temperature and then multiplying by 125. You can remember this formula as as H = (T-DP) x 125. If you have a smart phone in the field, you can get the current temp and dew point from the NOAA website and probably do the math in your head.

  If you're not so equipped, you can find the numbers later on your computer. Like I just have.

  Yesterday at 12:51 p.m., when I took these photos, the temperature was 46 degrees F and the dew point 35 degrees F. (Recall that dew point is the temperature below which water vapor condenses). So, that's an 11 degree difference, multiplied by 125 equals 1,375.

  Voila. The cumulus clouds in the photos above were floating 1,375 feet above the earth.

   I will try to understand why this works and explain it all to you in an upcoming post.

Look at the clouds! Do the math! Amaze your friends!  

Click here for NOAA website. Enter the zip code in the upper left for current conditions (including surface temp and dew point) in your area or wherever your cumulus clouds were hanging out. If your cloud photos are a few days old, use the link to "3 Day History" for the hourly temperature, dew point, and other data.

Unlikely Soundtrack for Cloudspotters

    Now more than ever I look forward to my transcontinental flights--even on the "busiest travel weekend of the year" and even when it means leaving the West Coast before dawn and taking non-direct flights. I am aggressive about getting my A-group boarding passes on Southwest Airlines so I can be assured of getting a window seat (south side of plane) without a wing-obstructed view. I keep my camera in my lap and as soon as we hit 10,000 feet, I am ready to photograph the clouds. 

   The clouds at sunrise on Wednesday morning were incredible (above)--even through a double layer of my not-to-clean plastic window. What you are mostly seeing here of altocumulus clouds--a mid-level cloud that hangs out between 6,500 ft. and 18,000 ft. But of course these aren't just altocumulus. They are altocumulus stratiformis opacus duplicatus. They are stratiformis because they cover a large area (as far as my eye could see here); they are opacus because they blocked the sun; and they are duplicatus because just below them--and out of the photograph because we hadn't hit cruising altitude yet--is a parallel layer of these altocumulus clouds.
   What I experienced (but most of my sleeping-upright-with-their-mouths-open family did not) were the few moments where our plane flew in between the two layers. It was stunning and surreal and made more so by the fact that at the space where the clouds seemed to meet on the horizon (the vanishing point) was suffused with orange light of the sunrise.
  It was like flying inside a grilled-cheese sandwich. The bread represents the two parallel layers of  clouds;  the orange cheese, the sunlight; the plane, a small piece of aluminum foil that accidentally got in the cheese.
   So it's not poetic, but the image works for me. I hope you never look at a grilled-cheese sandwich the same. 
    The Friday after Thanksgiving, I was planning to head into D.C. to see an exhibit at the Corcoran Gallery of Art called Spencher Finch: My Business with the Cloud. I had read a review of the exhibit by this American artist/photographer/collagist and was intrigued by the photograph (above) of Passing Cloud (2010) I had seen in a magazine review.

    Finch created this massive cloud, which hangs from the grand rotunda of the gallery, to recreate the same kind of refracted light that shone on one day in 1863 when President Abraham Lincoln and poet Walt Whitman crossed paths on a nearby street. Visitors to the museum are invited to walk under this historical artificial cloud and experience the shifting quality of light and changing colors found when walking under a real cloud. I wanted to walk under the cloud and enjoy the ensuing lofty thoughts, historical insights, and assorted epiphanies, but the more I thought about driving downtown to see a fictitious cloud made out of...Scotch tape, I decided to take a walk outside instead. I'm glad I did.

     Not only were there clouds, there was a lot of ch'i. The trees and clouds were putting a nice show (above). Everything was moving and energetic and uplifting in a way Scotch tape will never be.

    I walked briskly while taking photographs of the sky and trees and looking for the cloud du jour. There is always one.

     These cumuls fractus (above) were not the one, but coming from the land of evergreens, this ganglia tanglia of delicate deciduous branches was a refreshing sight.

   Nor were these fabulous cumulus humilis (above) the real show stoppers. Luckily, I needed to work off the five pieces of pie I had to sample at Thanksgiving dinner, so I kept walking. I was out for a good half hour before I found them (below).

      These cumulus clouds (fractus and humilis) were blowing in from the West and doing a wild burlesque as they alternately covered and revealed the glories of the sun. This is about the tenth photograph from a series I took shooting straight into the sun. I was so happy with the curvaceous "silver-lining" of the darkened cloud below and the iridescence of the windswept clouds above them that I actually jumped up and down with excitement. 

  I was not so happy with the 1977 hit tune that was uploaded into my inner ear as I was waiting for the black spots to fade from in front of my eyes. Oh, you know the song. "Blinded by the Light" sung Manfred Mann's Earth Band (but written by Bruce Springstein).

  Mama always told me not to look into the eyes of the sun.

     But Mama, that's where the fun is.