Summary:

## Surface Runoff, Surface Water Storage, and Infiltration

The article discusses the partitioning of moisture input at the grid cell surface, which is the sum of liquid precipitation reaching the ground and melt water from snow. This moisture flux is then divided between:

1. Surface runoff
2. Surface water storage
3. Infiltration into the soil

The key points are:

- The moisture input at the grid cell surface, denoted as `q_liq, 0`, is the combination of liquid precipitation and melt water from snow.
- This moisture flux is then partitioned between surface runoff, surface water storage, and infiltration into the soil.
- The article focuses on explaining this partitioning process, which is an important aspect of understanding the hydrological cycle and water balance at the grid cell level.