A modis-derived snow climatology (2000-2014) for the Australian Alps

Although not spatially extensive, the Australian Alps are scientifically significant as they are one of the few mid-latitude mountain ranges in the Southern Hemisphere. Because they are characterised by low elevations relative to other mountain ranges, the Australian Alps are a marginal area for seasonal snow-cover and are likely to be amongst the first areas to experience the effects of climate change. While numerous studies have examined temporal trends in Australian snow depths using ground-based observations, few have explored both the spatial and temporal trends in snow-covered area using remotely sensed observations. In this study, remotely sensed snow climatology for the Australian Alps was derived. The image time-series spanned 2000-2014 and was generated from imagery obtained by the Moderate Resolution Imaging Spectro radiometer (MODIS). Spatial and temporal trends in snow seasonality and snow-covered area were analysed, with results indicating that both the duration of snow cover and the amount of snow covering the Australian Alps was highly variable. The analysis further indicated that the snow-covered area decreased at a rate of 2.5% decade-1 across the study period. Although this trend was not statistically significant, it is the first time that the reduction in snow-covered area has been quantified for Australia. Furthermore, the automated methods employed in this study can be used to consistently process remotely sensed imagery, which can then be employed to monitor changes in Australian snow seasonality in the future.