Hurricane Dorian’s clear eye and near-circular symmetry, apparent in satellite images, signify a ferocious storm. The Bahamas are in serious, imminent danger. But for all we know about Dorian, which reached Category 5 on the Saffir-Simpson scale on Sunday with maximum winds of 185 miles an hour, one big question remains: Will it be a disaster for the United States?
Prof. Lorenzo Polvani has been named a 2019 AGU Fellow. Only 1% of AGU members are chosen for this honor in any given year and Polvani, also with the other 61 fellows, will be recognized at the Fall 2019 AGU Meeting in San Francisco, Calif. Polvani, who is a professor of Applied Physics and Applied Mathematics and of Earth and Environmental Sciences, is an atmospheric scientist whose research spans climate variability and change, tropical cyclones, the influence of the Arctic on other regions, and geophysical fluid dynamics.
"Lens" is the Latin word for lentil. And it is indeed true that the shape of bi-convex lenses—the familiar sort used as magnifying glasses—resembles those leguminous seeds. But that resemblance may soon be a thing of the past. For a group of engineers led by Nanfang Yu, Associate Professor of Applied Physics, has worked out how to make magnifying lenses that are flat, and thinner than a hair.
"The basic thing that makes extreme precipitation events heavier in the warmer climate is that there’s more water vapor in the air, and that’s a pretty unquestioned consequence of warming," says Adam Sobel, professor of applied physics and applied mathematics at Columbia University. "The amount of water vapor in the atmosphere increases roughly about seven percent per degree Celsius. And so, the baseline expectation is that heavy rain events get heavier at about that rate also. Some models increase them faster than that, and some slower."