We explore the evolution of mid-latitude circulation anomalies as a potential surrogate for changes in advection of moisture and heat using a sequence of progressively complex low order models. The Lorenz (1984) model is considered for mid-latitude circulation; it is then coupled to a Stommel Box model representing the Atlantic thermohaline circulation; and then these models are linked to a low order El Niño-Southern Oscillation (ENSO) model. The interaction between the Pacific ENSO model and the Atlantic (Stommel) model is also modeled. The integrated representations provide different levels of temporal interactions of tropical and mid-latitude circulation. The coupled models are used to assess how the probability distribution and temporal structure (low frequency variability) of circulation extremes evolves in such simple models, as the degree of interaction across these identified climate modes is introduced and varied. Model parameters are selected to conform approximately to the properties exhibited by the data observed over the 20th century. We note the intermittence and regime like behavior in the solution space as the purely atmospheric model (Lorenz '84) receives low frequency information from the other models. While moist circulation is not explicitly modeled, the results from the model(s) can be interpreted in terms of the potential changes in the key modes of eddy transport of moisture and heat. Parametric analyses of the effects as a function of the degree of coupling across the models are presented.
Scheda prodotto non validato
Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo
|Data di pubblicazione:||2008|
|Appartiene alla tipologia:||14p Visita presso Università o Ente di ricerca estero (almeno un mese)|