4.1.11 Day 2, 6AM: Gravity
Gravity is always at work, causing snow depth to decrease over time. As the snowpack ages or settles, its density gradually increases, which generally makes the snowpack more stable.
Gravity never works in isolation. Other processes, such as wind events and precipitation, often have a more dramatic effect on snowpack density and stability.
Note that when we mention stability in the context of snowpack, we're really talking about the likelihood of avalanche formation. A stable snowpack is less likely to fail and form an avalanche.