An iterative method for deducing the general temperature and moisture structure of the troposphere from satellite radiation measurements of medium spectral resolution is described. The temperature and moisture profiles derived from simulated and radiometrically observed radiances, pertaining t o clear atmospheres, are shown to agree favorably with the radiosonde profiles. The method is expanded...

Siphons have been used since ancient times, but exactly how they work is still a matter of debate. In order to elucidate the modus operandi of a siphon, a 1.5 m high siphon was set up in a hypobaric chamber to explore siphon behaviour in a low-pressure environment. When the pressure in the chamber was reduced to about 0.18 atmospheres, a curious waterfall-like feature appeared downstream from t...

Atmospheric oxygen (O(2)) is estimated to have varied greatly throughout Earth's history and has been capable of influencing wildfire activity wherever fuel and ignition sources were present. Fires consume huge quantities of biomass in all ecosystems and play an important role in biogeochemical cycles. This means that understanding the influence of O(2) on past fire activity has far-reaching co...

During my 2006-2007 VSGC fellowship I modeled the O2 atmosphere of Jupiter’s moon Europa. By assuming that atmospheric O2 can react with species contained in portions of Europa’s surface, my coauthors and I have been able to reproduce the O2 density variations seen by a previously-unexplained HST observation. This work included further refinements to a regolith model that I published previous t...

The effect of aerosols on 14 tropospheric photolysis reactions is examined under noncloudy and cloudy sky conditions by using a detailed one-dimensional radiative transfer model. Pure (NH4)2SO4, pure soot, and internal and external mixtures of the two aerosols, as well as mineral dust aerosol, are considered. Nonabsorbing aerosol generally enhances photolysis rates above and in the upper part o...

Interfaces, across which fluid and flow properties change significantly, are a ubiquitous feature of most turbulent flows and are present within jets, plumes, homogeneous turbulence, oceans and planetary atmospheres. Even when the interfaces occupy a small volume fraction of the entire flow, they largely control processes such as entrainment and dissipation and can act as barriers to transport....

Growth of Chlorella sorokiniana is unaffected by the choice of atmospheric diluent gas. Reduced total pressure has no inhibitory effect and may be slightly stimulatory.

The simple physics of microlensing provides a well-understood tool with which to probe the atmospheres of distant stars in the Galaxy and Local Group with high magnification and resolution. Recent results in measuring stellar surface structure through broad band photometry and spectroscopy of high amplification microlensing events are reviewed, with emphasis on the dramatic expectations for fut...

L10-ordered FePt nanoparticles (NPs) with ultra-high coercivity were directly prepared from a new metallopolyyne using a one-step pyrolysis method. The chemical ordering, morphology and magnetic properties of the as-synthesized FePt NPs have been studied. Magnetic measurements show the coercivity of these FePt NPs is as high as 3.6 T. Comparison of NPs synthesized under the Ar and Ar/H2 atmosph...

Recent results concerning the identification and measurement of nitrogenous air pollutants in the California South Coast Air Basin (CSCAB) are presented. In planning or evaluating studies of the human health effects of these pollutants, it is important to consider the entire range of species which may be present. We provide estimates of typical exposures to nitrogenous air pollutants during a s...