The climatic potential for beef cattle production in tropical Australia: Part III—Variation in the commencement, cessation and duration of the green season

Abstract

Part I demonstrated a method for deriving from standard meteorological data a ‘green season’ and a ‘dry season’ which correspond to the main periods of liveweight gain and loss respectively of cattle on native grass pastures. This paper describes (a) the geographic variation in the incidence and duration of the green season utilising a network of 77 stations in tropical Australia, and (b) the year-to-year variability for eight of these stations. Variability in the date of commencement of the green season (the termination of the dry season) differed among stations, with ranges as low as 11 weeks and as high as 20. Differences of up to 16 weeks in the median duration of the green season between stations occurred within the study area, while the range of variation from year to year at a station was as low as 13 weeks and as high as 34. Results are compared with those of previous descriptions. Difficulties imposed on management by climatic variability are discussed.