Question

In areas under heavy snow, how can snow contribute to ground instability and potential landslides?

• A. The snow acts as a protective barrier, preventing landslides.
• B. The weight of the snow itself and melting snow can saturate the ground.
• C. The snow causes the ground to become more cohesive and firm.
• D. The snow absorbs water, preventing soil saturation.

Answer 1

Answer:

B. The weight of the snow itself and melting snow can saturate the ground.

In areas under heavy snow, snow contributes to ground instability and potential landslides in two main ways:

1. Weight of the Snow Itself:

   • A significant accumulation of snow adds a substantial load to the ground or slope.

   • This added weight increases the gravitational force acting on the underlying soil or rock, making the slope more susceptible to failure, especially if the ground is already weak or saturated.

2. Melting Snow Saturates the Ground:

   • As temperatures rise, the accumulated snow melts, releasing a large volume of water.

   • This meltwater infiltrates the ground, saturating the soil.

   • Similar to heavy rainfall, this saturation increases the soil's weight and, crucially, reduces the friction and cohesion between soil particles, weakening the slope and making it prone to sliding.

   • In areas with frozen ground (permafrost or seasonally frozen soil), melting snow can create a saturated layer above the frozen, impermeable layer, leading to instability and shallow landslides.