Estimating the Rate of Growth or Shrinkage of the Amundsen Crater PSR Area

Permanently shadowed regions (PSRs) contain some areas [Figure 1] where frozen volatiles can be observed at the lunar poles. They have maximum surface temperatures < 100 K [1, 2].
Surface temperatures in these shadowed regions are largely controlled by reflected sunlight and irradiated infrared light from adjacent topography [3-6]. These areas are cold traps, capable of accumulating water and other volatile compounds over time [7].
There is a lack of understanding regarding the surface thermal changes at these PSRs, particularly how these pockets of < 100 K temperatures change on a yearly basis and may inhibit growth or shrinkage of volatile accumulation or ablation, respectively.
Here, we measure the bolometric temperatures derived from Diviner over several years (2010-2016).