Variación espacio-temporal del cambio de agua total almacenada y la precipitación usando datos GRACE y TRMM de Lima-Callao en Perú

Spatio-temporal variation of the anomalies of the gravity field associated with the change in total water storage and precipitation in Lima-Callao was analyzed. GRACE (Gravity Recovery and Climate Experiment) and TRMM (Tropical Rainfall Measuring Mission) data monthly were introduced in this study. Autocorrelation, cross-correlation and decomposition analysis of the time series was performed, finding that both series present annual cycles but with different intra-annual variations. The gravitational anomalies increased and decreased in an annual cycle, positive gravitational anomalies varied from December to Ma y a nd negatives gravitational anomalies vary from June to November. Precipitation mainly presents an annual cycle, although other frequencies of lower spectral power of 6, 4 and 3 months were found, precipitation increases from August to March, decreases rapidly until May followed by a dry period from May to August. Cross correlation was applied between both time series obtaining a maximum correlation coefficient of 0.8677 for a lag of two months, this lag seems to be related to the recharge mechanisms of the total water storage, which reveals that the Lima-Callao region receives indirect recharge.