Climate variability effects on spatial soil moisture dynamics

We investigate the role of interannual climate variability on spatial soil moisture variability dynamics for a field site in Louvain-la-Neuve, Belgium. Observations were made during 3 years under intermediate ( 1999), wet ( 2000), and extremely dry conditions ( 2003). Soil moisture variability dynamics are simulated with a comprehensive model for the period 1989 - 2003. The results show that climate variability induces non-uniqueness and two distinct hysteresis modes in the yearly relation between the spatial mean soil moisture and its variability. We demonstrate that the direction of hysteresis is related to a yearly climate index that does not require soil moisture observations.