cloud series chronology
1971U of I, Champain-Urbana, Illinois, First sailplane instruction with attendant study of micrometeorology, thermals, and fair weather cumulus formation. Began to wonder about creating synthetic thermals and the visual realtionship of clouds to raster computer graphics.
2000-2004Central New Mexico, resumed flying sailplanes in superb conditions in the Southwest. Continued thinking about creating synthetic cloud patterns using thermal triggers on the ground. Started paying particular attention to the types of ground features which seem to reliably form thermals and attendant clouds if the conditions are correct.
5/5/04First written mention of Cloud Series in companion notes on Reentry Series. These notes describe other large scale kinetic environmental pieces.
5/6/04Registered billdolson.com with network solutions for website
5/9/04First formal writeup of Cloud Series posted to website
5/8/04Road tour of western New Mexico with Sally Beers including Plains of San Augustine and the VLA. Wouold make a great site!, sspecially due to how the black circles on the ground would relate to the white dishes of the VLA. Wonder if the area has any deeded land or if there are airspace restrictions.
5/9/04Added Cloud Cross to Cloud Series, first version started with Cloud Box and Array. Added additional notes on motivation and site. Sketch of first study posted to website.
5/11/04Talked about piece to Sally, wondering if perahps I should get in touch with Jim Turrel to get benefit of his experience with large scale artworks on private land and legal, etc. Maybe he could refer me to counsel experienced in this sort of thing as the piece has a life expectantcy of 10 years with just the first application of material and little maintenance.
5/18/04Telephone conversation with Tom Bradbury in England. Mr. Bradbury is a noted British meteorologist who has has written extensively about the effects of weather on aviation, having been a meteorologist for the RAF for much of his career. He has written articles for sailplane pilots and the soaring community on the formation of clouds and thermals. For instance, "Evolution of Cumulus Clouds", Soaring, April 2002. Mr Bradbury has also been a lifelong soaring pilot and has shown an empirical and intuitive understanding of cloud formation in his articles based on his piloting experience as well as technical work. His articles were very influential in my development of the ideas for the Could Series. I called him at his home in England, explained that I am a US soaring pilot and artist and was planning a series of artworks which would involve creating synthetic cloud patterns in the sky using ground-based thermal trigger zones. His initial reaction somewhat surprised me in that far from expressing any sort of disbelief or scepticism, his immediate response was the he "found the idea fascinating" and "if he was 20 years younger he would love to be involved". He questioned me about the means to produce the dark areas on the ground and I explained about using road surface treatments applied by sprayer trucks which he felt was very practical.

I asked him if there were any scientific journals in which findings might appear on the detailed mechanisms of thermal formation. He indicated that the details of cloud formation, particularly fair weather cumulus, have to his knowledge, not been studied particularly well, most work concentrating on the development of thunderstorms or large scale weather patterns. He did indicate that due to his age and poor eyesight he has not kept up on the literature for the last ten years or so, so I would have to do some digging. I asked if he was aware of any studies which involved artificial generation of thermals and clouds to study the optimal size of ground trigger zones. He did not know of any being reported. He indicated that the Meteorological Office in Cardington, Bedfordshire, had done some fairly elaborate studies which involved using barrage baloons to loft atmospheric instruments to study cloud formation. He said I might be able to obtain the results from the Meteorological Office in London. Another study he recollected was done by he thought an American sailplane pilot, Betsy Woodward, with the Imperial College, London, shortly after WWII. This study produced some very convincing models of cumulus-like formations by pouring a layer of a dense saline solution with a visible tint over a layer of fresh water in a tank and allowed them to slowly mix, with the result very much resembling cumulus clouds.

I asked him, in the light of no known studies about the optimal size of ground trigger zones for thermals, what his feelings were about the suitable sizes for such trigger zones. He indicated that British saoring pilots have observed that features of the size of an airstrip (a tarmac strip nominally a mile in length) usually produce thermals. This is consistent with the common experience of US soaring pilots with their home field having a "House Thermal". He related a story he had heard recently that someone in the UK had studied the flight of homing pidgeons and discovered they do not use the most direct route, but instead follow motorways and it was speculated that this was to make use of the lift from the thermals off the road surface. I questioned him about his gut feel for the smallest feature which would produce a thermal and he felt something in the order of a few hundred meters. I explained about my proposed test with dark circles of increasing diameter and he said he would very much like to see the results of such a test. He also indicated that he felt time-lapse photography would be af great use in studying the performance, that he had made a start at one time to do so. I told him that I felt similarly and that in fact I felt that the formation of the patterns I was trying to achieve might never or only rarely be visible simultaneously due to the random growth and decay cyles of thermal formation, that they might only appear in a time-lapse study. He agreed with this hypothesis.

I obtained his mailing address and promised to drop him a note to keep him abreast of my progress and so that he could contact me if any pertinent information occurred to him. He was most cordial and encouraging and I indicated that while he was not able to provide me with concrete data regarding my endeavor, his interest and assesment of it's feasibility was perhaps the most valuable contribution he could make. I promised to stay in touch.

3/3/05Minor revision of website writeup.