Seasonal to multi-year soil moisture drought forecasting

The effects of ocean and land initializations are disentangled using two large ensemble datasets-initialized and uninitialized experiments from the CESM. We find that soil moisture has significant predictability on S2D timescales despite limited predictability in precipitation.

On sub-seasonal to seasonal timescales, precipitation variability is an order of magnitude greater than soil moisture, suggesting land surface processes, including soil moisture memory, reemergence, land-atmosphere interactions, transform a less predictable precipitation signal into a more predictable soil moisture signal.