It
implies that any variable (e.g., annual stream-
flow or annual flood peak) has a time-invari-
ant (or 1-year–periodic) probability density
function (pdf), whose properties can be esti-
mated from the instrument record. Under sta-
tionarity, pdf estimation errors are acknowl-
edged, but have been assumed to be reducible
by additional observations, more efficient
estimators, or regional or paleohydrologic
/media/loftslag/Milly_etal-2008-Stationarity-dead-Science.pdf