High frequency hydrological signals in GRACE time-variable gravity solutions

The GRACE Release 04 (RL04) series have long been shown to accurately pick up signal at and near the annual frequency. Due to the monthly nature of most RL04 products, however, the accuracy of faster-moving GRACE signals has been difficult to determine. Through the use of an overlapping windowing technique, the frequency resolution of GRACE has been enhanced, allowing weekly to monthly signals to be analyzed. We compare these GRACE results to groundwater and stream flow data, as well as to the GLDAS model, and focus particularly on the frequency regime above 3 cycles/year.