Trends in stream base flow in American Samoa and Guam, 1978-2008, showing no significant trend


Figure 2-14  Streamflow records available for the Western North Pacific and Central South Pacific sub-regions are relatively short and mostly discontinuous, and many have been affected by upstream diversions or other human activities. Analysis of data from 1978 to 2008 from two gauges on Guam and one on Tutuila, American Samoa, showed no statistically significant trends (red dashed line) in the number of extreme high- or low-flow days. The lack of significant streamflow trends on Guam and American Samoa is consistent with rainfall observations but may also be an artifact of short record available for analysis, highlighting the need for consistent and high-quality monitoring in these subregions. (From Miller et al., 2012.)