Lack of rainfall is not the only measure of drought. New UC Riverside research shows that despite a series of storms, the impact of drought can persist in streams and rivers for up to 3.5 years.
There are two measures of drought in streams. One measure is the total water level, which is impacted by snowmelt and rainfall. Many researchers examine this measurement. Another measure is baseflow, which is the portion of streamflow fed by groundwater.
Fewer researchers examine baseflow droughts, and there was not previously an accurate way to measure them. Because baseflow is strongly tied to groundwater, and because the lack of it has significant impacts on water management and ecosystem services, the UCR team decided to examine baseflow more closely.
“People often just use rain as an indicator of drought because it’s easier to measure. But there are other kinds of drought that each have their own impacts,” said Hoori Ajami, study corresponding author and associate professor of groundwater hydrology at UCR. “We needed a new way to see how long it takes for one form of drought to become another form.”
Read more at University of California - Riverside
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