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Ponds are characterized by high biodiversity, intense biogeochemical cycling, and susceptibility to anthropogenic impacts. Yet few studies have quantified the water velocities responsible for vertical mixing or lateral transport in ponds. We used high‐resolution observations of velocity to examine mixing and transport during summer in a 50‐m‐long, 2.7‐m‐deep temperate pond. Many observed transport and mixing processes resembled those found in larger stratified lakes. A surface mixed layer was observed, whose depth ranged between ~ 1 m at night and < 0.3 m during the day. Turbulence was usually sufficient to vertically mix the surface layer in 4–12 min, but no turbulence was observed in the hypolimnion. Persistent (2.5‐h‐averaged) currents usually flowed downwind near the surface and returned upwind near the mixed layer base. Surface currents were proportional to windspeed, with root‐mean‐squared speed of 8×10−3ms−1$$ 8\times {10}^{-3}\ \mathrm{m}\;{\mathrm{s}}^{-1} $$ (persistent hypolimnion currents were much weaker). Superposed on persistent currents were 30‐ to 100‐min‐period fluctuations resulting from internal seiches. These fluctuations were comparable in magnitude to more persistent currents in the mixed layer and dominated in the hypolimnion. Seiches did not advect particles far across the pond, but did contribute to production of mixed layer turbulence. Seiches also contributed to shear dispersion, which was sufficient to mix near‐surface tracers across the pond in 2–4 d. Theory suggests that hypolimnion bottom boundary layers were laminar during the downslope phase of seiche motion, but became turbulent during the upslope phase as near‐bed water flows created unstable stratification. [ABSTRACT FROM AUTHOR]

The Fourth Amendment is a mirage. On paper--in the rules studied by law students, analyzed by scholars, and proclaimed by jurists--its limitations are many and, oftentimes, significant. Yet the experience of large numbers of Americans is entirely to the contrary, thanks to the rights-annihilating, under-theorized exception of "consent." Under its guise, law enforcement officers routinely conduct what would otherwise be constitutionally-restrained searches and seizures, and they do so without meaningful explanation or assent. Fortunately, change--whether legislative or (ideally) constitutional--could be straightforward. Thanks to other sufficient triggers, consent could be replaced by a narrow, rights-protective doctrine under which law enforcement could continue to accomplish its aims--and in a more fair and evenhanded manner--and that would produce public data that could be mined for evidence of bias or manipulation. In this Article, then, we make the case for the abolition of Fourth Amendment consent except as an emergency doctrine, a move that would improve policing and restore an intended measure of human dignity and autonomy to the people. [ABSTRACT FROM AUTHOR]