Celebrating the physics of all that flows with Nicole Sharp, Ph.D.
- Profile
The Great Haboob Chase
Few sights look as apocalyptic as the leading edge of an incoming dust storm. Known as a haboob, these storms form when a downdraft spreads along the ground, picking up loose dust as the storm front advances. Winds inside the haboob can be severe; when one swept through Denver last year, my first clue was…
Stratospheric Effects of Wildfires
Australia’s bushfires from earlier this year are offering new insights into how pyrocumulonimbus clouds can affect our stratosphere. A massive, uncontrolled blaze between December 29th and January 4th generated a towering, turbulent cloud of smoke like the one shown above. Using meteorological data, a new study shows this enormous cloud initially rose to 16 km…
Hummingbird Flight in Slow Motion
Hummingbirds are impressive, acrobatic flyers. Their figure-8 wing stroke pattern produces about 70% of their lift on the downstroke, and the remainder during the backward upstroke. But their tails and body motions also play an important role in stabilizing them, especially in gusty winds. They also have some impressive feeding dynamics. Altogether, they’re one of…
Recession at Taku Glacier
A glacier’s snowline marks the location where the amount of summer melting and accumulated snowmass are equal. If, over the course of a season, a glacier experiences more snowfall than melting, its snowline will advance. If melting outweighs accumulation, then the snowline will retreat to higher altitudes. Tracking the snowline gives scientists important data about how the…
Simulating Better Breaking Waves
In the ocean, breaking waves trap air into bubbles that then cluster into foam, but conventional simulations don’t capture this foaminess. For bubbles to cluster into foam, there has to be a force preventing — or at least delaying — their coalescence. Typically, this is caused by impurities in the water that help lower the…
Psychedelic Soap Film
Macro images of a soap film burst with color. Because the color comes from interference between light waves bouncing off the inner and outer surfaces of the soap film, the colors we see correspond directly to the thickness of the soap film. So the patterns we see reflect actual flows and variations inside the soap…
Contrails From 4 Engines
The wingtip vortices of aircraft provide a veritable cornucopia of gorgeous imagery. There’s something inherently fascinating about these vortices that stretch behind moving aircraft. But four-engine aircraft add an extra twist to the imagery, as seen here. With four engines, these aircraft produce four separate contrails, each of which acts like a streakline for the…
Preventing Flooding
The Dutch have been exceptional water engineers for centuries, a necessity in a country where more than a quarter of its territory lies below sea level. After a devastating flood in the early 1950s, the country embarked on a decades’ long endeavor to build the massive Delta Works that now protect a large portion of…
The Wanderings of Micro-Scallops
In the 19th century, botanist Robert Brown observed pollen granules beneath his microscope jittering randomly. Einstein showed that this motion resulted from the impacts of much-smaller atoms against the particles. For small enough objects, the random walk of Brownian motion dominates their dynamics. A new study explores how flexible objects move at this Brownian scale.…
The Magic* Cork
*Spoiler alert: it’s not magic. It’s science! Just what makes this dropped cork float beneath the surface? Just like a normal cork, it’s buoyancy! But this seemingly straightforward video is hiding a few key elements. Firstly, the cork has been modified; it has a metal sphere inside it so that its effective density is higher…