Further analysis involved calculating yearly averages as well as the spatial representation of albedo change across Austfonna.
Key points from these figures are as follows:
- Yearly averages (αyearly) disclose no overall trend, but this masks an almost sinusoidal pattern whereby early and late trends cancel one another. Initial multi-year decline of 0.018 ± 0.0034 year-1is halted in 2005. Increases are then seen until 2008, whereby another significant forcing reversed the trend once again,into a decreasing trend at 0.0194 ± 0.0029 year-1.
- Average monthly albedos also show a slight change in pattern from the eastern Arctic glacier’s with July not providing the greatest proportion of albedo decline and June the only month showing any real decline (0.0063 ± 0.0016 year-1).
- Regionally 86% of the glacier has seen a decline in albedo.
- In contrast to Humboldt Glacier, αdaily exhibits greater short term variability throughout June, July and August. Defining an extreme variance shift as a five unit swing over a period of 3 days, the current declining period (2008 – 2013) has 41 shifts, compared to 16 on Humboldt Glacier
Advertisements
