Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
Breaking in Rogue Seas
Many models for forecasting ocean waves simplify the physics by assuming that waves are essentially two-dimensional, like a long breaker heading toward shore. But in the open ocean, waves often come from more than one direction; crossing seas are a good example. When waves from different directions combine, a recent study shows, the resulting wave…
When Fires Make Rain
The intense heat from wildfires fuels updrafts, lifting smoke and vapor into the atmosphere. As the plume rises, water vapor cools and condenses around particles (including ash particles) to form cloud droplets. Eventually, that creates the billowing clouds we see atop the smoke. These pyrocumulus clouds, like this one over California’s Line fire in early…
“Immersion”
Some seabirds, including gannets and boobies, feed by plunge diving. From high in the air, they fold their wings and dive like darts into the water, impacting at speeds around 24 m/s to help them reach the depths where their prey swim. With their narrow beaks and necks, the critical moments in this feat come…
Engineering Our Landfills
We create a lot of waste and, at least for now, much of that waste goes into landfills. Properly managing garbage requires much more than digging a hole in the ground, as Grady from Practical Engineering shows in this video. Maintaining a landfill requires careful management of water, soil, landfill strata, and even gas buildup.…
The Crashing Waves of French Polynesia
Surfer and photographer Tim McKenna lives in the village of Teahupo’o on Tahiti’s southeastern coast. The area’s shallow coral reef system creates some of the world’s biggest barreling waves, which attract surfers from around the world. McKenna captures the majestic power of these surges in these black-and-white photographs; you can find more of his work…
Slushy Snow Affects Antarctic Ice Melt
More than a tenth of Antarctica’s ice projects out over the sea; this ice shelf preserves glacial ice that would otherwise fall into the Southern Ocean and raise global sea levels. But austral summers eat away at the ice, leaving meltwater collected in ponds (visible above in bright blue) and in harder-to-spot slush. Researchers taught…
Swimming With Cilia
Like most microswimmers, these Synura uvella algae use cilia to swim. Cilia are tiny, hair-like appendages that flap to produce thrust. Even under a microscope, the cilia are hard to see because they are so thin and move quickly in and out of the microscope’s narrow focus. A cilia’s stroke is always asymmetric — no…
Peering Inside Viscous Fingering
Viscous fingers form when a low-viscosity fluid is pumped into a narrow, viscous-fluid-filled gap. The branching pattern that forms depends on the ratio of the two viscosities, among other factors. To better understand what goes on inside these fingers, researchers carefully alternated injecting dyed and undyed fluid. This creates a pattern of concentric rings that…
More Gigantic Jets
It’s wild that we’re still discovering new weather phenomena, but the gigantic jets seen here were only identified in 2002. This uncommon type of lightning shoots up from the tops of thunderstorms into the ionosphere. The video/image above was caught by cameras normally used to monitor meteors. The jets themselves are red in color, a…
First Ice
The early light of dawn illuminates ice forming at the edge of this pond in Vermont. Caught after a frigid mid-November night, the ice is some of winter’s first. The interface between seasons reflects the interface in water phases. (Image credit: A. Raeder; via CUPOTY)