Saturday, December 9, 2017

       BIGGER  PLANETS DEMAND  BETTER  CLIMATE  MODELS

NASA'S  Juno probe scanned this near IR false color  photo during its ninth orbit around Jupiter. The depth and detail is unprecedented.  At roughly ten miles per pixel,  the image shows shadows being cast on the lower cloud decks  by the grotesquely turbulent storms atop them. 

What it doesn't tell is the range and intensity of the physical conditions  it encompasses- the lowest depths of Jupiter's visible atmosphere experience  pressures higher  than the Earth's deepest oceans , and still deeper, but far from the gas giant's center, they surpass the temperature of the center of the earth.

Before long, a full pelt  Jovian climate model will  have to handle the hydrodynamics not just of cold gases but incandescent supercritical metallic hydrogen, and Lord knows what other pressure degenerate and metallically conductive  molecular species coexist with it in the ocean of  complexly alloyed supercritical fluids  convecting and swirling  in the depths below what this image reveals.  It took decades of effortto produce  the meerest speck of metallic hydrogen in a Harvard lab last year, and it only lasted for a few weeks before the diamond anvils compressing it to five million atmospheres exploded as a laser probed its optical properties.

Earthly climate modeling isn't easy, but the Jovian GCM builders have harder work in store- to understand the components of the atmosphere they are trying to model, their experimentalist colleagues must advance to even more daunting pressures and temperatures  in the lab.