Melt inclusions trapped in phenocrysts provide a unique picture of magma systems prior to modification by crustal processes. However, post-entrapment crystallization complicates their interpretation. Re-heating the phenocryst to the temperature of entrapment is a commonly applied method to recover the original melt composition. To understand the effects of re-homogenization, we...
An approach developed recently to study the dynamics of vorticity defects in homogeneous
shear flow extends naturally to the case of baroclinic, quasi-geostrophic
flow. It is shown that an inviscid geostrophic flow with uniform vertical shear may
be destabilized by introducing a `potential vorticity defect', an arbitrarily small but
sufficiently...
The dynamics of the growth of linear disturbances
to a chaotic basic state is analyzed in an asymptotic model of
weakly nonlinear, baroclinic wave-mean interaction. In this
model, an ordinary differential equation for the wave amplitude
is coupled to a partial differential equation for the zonal
flow correction. The leading...
• Premise of study: In the mixed evergreen forests in the western United States, Arbutus menziesii is able to quickly resprout following disturbance and, as such, act as a nurse tree during forest regeneration. The mechanism for this nurse tree effect has frequently been ascribed to mycorrhizal fungi, but no...
Management in fire-prone ecosystems relies widely upon application of prescribed fire and/or fire surrogate (e.g., forest thinning) treatments to maintain biodiversity and ecosystem function. Recently, published literature examining wildlife response to fire and fire management has increased rapidly. However, none of this literature has been synthesized quantitatively, precluding assessment of...
Rubus seed has a deep double dormancy that restricts germination due to seed coat structure and chemical composition. Improved germination of diverse Rubus species required for breeding improved blackberry and raspberry cultivars is partly dependent on the seed coat structure. This study evaluated the seed coat structure of three species...
Two simplified ocean simulations are used to study circulation and transport within Nares Strait. The simulations are similar, except that one included a coupled sea ice model that effectively established a landfast ice cover throughout the simulation year. Comparison between the ocean-only and ocean-ice simulations reveals a systematic change in...
Satellite observations of ice motion are combined with model estimates of low‐level winds and surface wind stress to provide evidence for atmospheric control of sea‐ice motion through Nares Strait, between Ellesmere Island and Greenland, during two periods in 2004. The results suggest that ice flux through the strait, and its...
Disturbance events strongly affect the composition, structure, and function of forest ecosystems; however, existing US land management inventories were not designed to monitor disturbance. To begin addressing this gap, the North American Forest Dynamics (NAFD) project has examined a geographic sample of 50 Landsat satellite image time series to assess...
We describe an upper-division experiment in thermal physics where students measure the tension
of a rubber band as a function of temperature and length, and use a Maxwell relation to find the
change in internal energy and entropy for an isothermal stretch. This allows students to experimentally check the predictions...