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We investigated scaling of conservative solute transport using temporal moment analysis of 98 tracer experiments (384 breakthrough curves) conducted in 44 streams located on five continents. The experiments span 7 orders of magnitude in discharge (10(-3) to 10(3) m(3)/s), span 5 orders of magnitude in longitudinal scale (10(1) to 10(5) m), and sample different lotic environments-forested headwater streams, hyporheic zones, desert streams, major rivers, and an urban manmade channel. Our meta-analysis of these data reveals that the coefficient of skewness is constant over time (CSK = 1.18 +/- 0.08, R-2 > 0.98). In contrast, the CSK of all commonly used solute transport models decreases over time. This shows that current theory is inconsistent with experimental data and suggests that a revised theory of solute transport is needed. Our meta-analysis also shows that the variance (second normalized central moment) is correlated with the mean travel time (R-2 > 0.86), and the third normalized central moment and the product of the first two are very strongly correlated (R-2 > 0.96). These correlations were applied in four different streams to predict transport based on the transient storage and the aggregated dead zone models, and two probability distributions (Gumbel and log normal).