The classification of clouds 26 Nov 201228 Nov 2012 [A segment of my new book, coauthored with Malte Ebach] The classification of clouds Clouds were regarded as so subjective, fleeting and resistant to classification that they were a byword for the failure of empirical classification, until Luke Howard in 1802 proposed the foundation for our present system of cloud classification (in competition, although he did not know it, with others in Europe, and on the heels of Hooke and later meteorological language proposals including one by Lamarck the same year. Howard’s proposal, like Lamarck’s, was driven solely by empirical observations. No experiment was possible with clouds (although there were some schemes for building cloud producing machines early on), and there was no real theory as such, just a desire to, as Lamarck said, note that “clouds have certain general forms which are not at all dependent upon chance but on a state of affairs which it would be useful to recognise and determine” (Hamblyn 2001: 103. This section is taken mostly from Hamblyn’s excellent book). In short, this is an example of a classification scheme without much if anything in the way of Theory. Howard proposed seven classes (genera) of clouds – three “simple modifications”, cirrus, cumulus, and stratus, two “intermediate modifications”, cirro-cumulus, and cirro-stratus, and two “compound modifications”, cumulo-stratus and cumulo-cirro-stratus, or nimbus. His criteria used apparent density, elevation, height, and whether it produced rain. Particular types of clouds were called, following the logical and Linnaean examples, “species”. He also devised our present system of signs for these cloud types, and proposed a correlation with certain types of rain and clouds. Now meteorologists could communicate and seek explanations and presently the International Cloud Atlas is the global standard for identifying clouds (World Meteorological Organization 1975). This is a classic example of an empirical passive classification. Although the hydrological cycle was of ancient vintage, the direct Theory of clouds, such as it was, had to await the hypothesis of the thermal theory of cyclones and cloud formation (Kutzbach 1979). Similar passive classifications were done for wind, resulting in the Beaufort Scale. Howard’s scheme outcompeted Lamarck’s largely because of its technical terminology and signs. Lamarck’s was too French and odd even for them. It gained great acceptance. Johann Wolfgang von Goethe, had written a poem in Howard’s honor, as well as contribute “Towards a Study of Weather” in which he briefly discusses Howard’s categories of clouds and a basic law of weather (Goethe 1825 (1970)). Bibliography Goethe, Johann Wolfgang.von. 1825 (1970). Versuch einer Witterungslehre. In Die Schriften zur Naturwissenschaft, edited by D. Kuhn and W. von Engelhardt. Weimer: Hermann Böhlaus Nachfolger:244-268. Hamblyn, Richard. 2001. The invention of clouds: how an amateur meteorologist forged the language of the skies. London: Picador. Kutzbach, Gisela. 1979. The thermal theory of cyclones: a history of meteorological thought in the nineteenth century. Boston: American Meteorological Society. World Meteorological Organization. 1975. International Cloud Atlas. Secretariat of the World Meteorological Organization:155 pp. History Natural Classification Science Species and systematics Systematics
Ecology and Biodiversity Trashcan: hobs and goblins 10 Dec 2008 I’ve been travelling a little to organise my move to Sydney. Love the building, the department, the people and the project. Not sure about Sydney… so anyway, nothing of substance from me for a while. Here’s a lovely little essay about Newton pissing off most of the European intellectual giants… Read More
Philosophy Neurath on the surface 8 Sep 2009 Charles Wolfe pointed me at a comment of Otto Neurath’s: The scientific world conception is characterised not so much by theses of its own, but rather by its basic attitude, its points of view and direction of research. The goal ahead is unified science. The endeavour is to link and… Read More
Ecology and Biodiversity Virulence and vectors 18 Mar 202018 Mar 2020 Apropos of nothing, I am reminded of Paul Ewald’s book Evolution of infectious disease (1994). Ewald begins with the question of whether parasites and pathogens evolve towards commensuality (the state of being mutually beneficial, which is what, among others, Macfarlane Burnet thought, along with many immunologists and epidemiologists. Ewald points out… Read More
I always triple check posts containing spelling nits before sending! Actually, I knew someone in the Cloud Appreciation Society.
It always puzzles me that the Beagle is famous but the contribution to wheather forcasting made by Fitzroy its captain hardly gets a mention. I’m also fasintcaed taht we can raed mspileled wrods as lnog as the frist and last lrettes ar in the rhgit place.
Just been reading Minsky on Frame Theory. This sentence made me laugh. When we look up, we are never afraid that the ground has disappeared—no matter that it has…”