Time-series Analysis of Late Summer Snow Patches in Northern Swedish Lapland

Snow patches are found all over in high-mountain and arctic areas. In these regions climate change is supposed to be faster than at other latitudes and the change is predicted to be very likely to continue. In recent decades, remote sensing data are extensively used for change detec-tion analysis due to climate change processes. In many research strategies the change in vegeta-tion cover is used to indicate a change in landscape. But the slow and very gradual changes in vegetation cover are hard to be detected in multi-spectral satellite imagery. This study uses four-teen satellite images covering the time period from to 2006 to explore spatial and temporal varia-tions in the extent of late summer snow patches in the Abisko Mountain in subpolar Northern Sweden to detect the impact of climate change. Late summer snow patches are used because they interact with weather conditions on an annual scale and they contrast extremely with no-snow areas in satellite imagery which makes their analysis feasible and significant in the statistical sense. Landsat, Aster, IRS and SPOT satellite data are used for this study covering a period of 34 years.
Since there exist extreme climate gradients in the area from maritime to continental climate within a distance of 100 km special attention had to be paid on this regional variability. Therefore special statistical filter techniques were developed to tackle the problems of climate gradients of snow precipitation, altitudinal effects etc.