Relation between short-term and long-term variations of precipitation

Abstract

It is often stated that short-term precipitation of synoptical weather is related to trends or interannual variations of precipitation. We analyzed nine long-term series of daily precipitation values of the Global Historical Climatology Network (GHCN-D V2.0). Generally, the mean amplitude of short-term variations increases (decreases) if there is a positive (negative) interannual anomaly of precipitation, respectively. In all cases, the amplitude of the short-term variations (periods < 10 days) clearly correlates with the long-term variations (periods > 1.5 years) of precipitation. The correlation coefficient is between 0.7 and 0.95 at periods < 8 days. For Kukuihaele (Hawaii), the correlation maximizes at a period of about 14 days. In the other cases, the maximum of the correlation is reached at periods < 5 days.