- On the Modifications of Clouds
Contemporary climate modeling is a form of mathematical simulation of a reality that is treated in the manner of an experiment. It differs from many kinds of laboratory experiment in that the outcomes of its manipulations can't be compared with an unmodified control state because of the complexity of its object. The planetary climate system is governed by a combination of the laws of fluid dynamics, thermodynamics, radiative energy transfer and chemistry, and is composed of the atmosphere, the oceans, ice sheets and land. Each of these four subsystems is coupled to each of the other three through the exchange of immense quantities of energy, momentum and matter. Nonlinear interactions occur on a dizzying range of spatial and temporal scales, both within and between the subsystems, leading to an intricate and delicate network of feedback loops.
Climate is, in short, a chaotic phenomenon, and simulation modeling is characteristically applied to chaotic phenomena such as a severe storm, a gas jet, or the turbulent flow of water, where, although the underlying physical theories are well understood, the complexity of the interactions involved means that they cannot be simply applied. The continuous differential equations that express the rates of change of such dynamic phenomena over infinitesimal intervals must be converted into algebraic difference equations, which express rates of change in terms of discrete and discontinuous intervals and which can be computationally solved.
Climate modeling constructs a range of counterfactuals in order to explore alternative states of the climate in a virtual environment; it is only through simulations that you can systematically and repeatedly test variations in the forcings (the variables that control the climate system), and only through modeling that you can create a control—a simulated Earth with pre-industrial, Wordsworthian levels of greenhouse gases—against which to analyze what is happening on the real Earth. And although it differs from traditional laboratory experiments, climate modeling is like experimental work in that it is the behavior of the model or simulation itself that is the object of investigation. [End Page 369]
Wordsworth and the Poetics of Air is, at the most general level, a book about the transformation of the concept of "atmosphere" that happens around 1800, and about how Romantic atmosphere aquires a language of indeterminacy—a language of cloudiness, of mist, of the shifting forms of things—that anticipates the language of chaos, seeking to give a determinate form to this indeterminate atmospheric medium, whilst at the same time being subject to the paradoxes of its own necessary indeterminacy, in the same way as the mathematical theory of chaos remains subject to the ever-receding limits of its own nonlinear language.
The book's analysis is thus in part a matter of exploring the interplay between a semantic field that models indeterminacy and the language of poetry that, in constructing that field, is caught up recursively in what it models. Let me take as an example of how this happens the reading of Goethe's homage to Luke Howard, whose essay "On the Modifications of Clouds," published in 1803, marked the emergence of "the modern science of weather as a planetary system of fluid dynamics." The poem is Howards Ehrengedächtnis, and Ford's reading of it begins with a history of the genre of the Ehrengedächtnis, the inscription or memorial of honor, from its funerary origins to a form of autonomous textuality that restages in writing the event of interring the dead. The poem is in part an act of translation by Goethe of Howard's categories which are inherently and by design untranslatable, and there is an excursus on Goethe's theory of three modes of translation, developed in relation to the Sanskrit intertext Goethe draws on as well as a series of Shakespearean intertexts that the translator of that Sanskrit text adduces. This is then followed by a virtuoso reading of the systematic phonemic permutations (the "metaplasmic transformations") through which the poem mimes atmospheric instability. Clouds are here the model: when Hamlet is...