The HYSPLIT_4 (HYbrid Single-Particle Lagrangian Integrated Trajectory) model is designed for quick response to atmospheric emergencies, diagnostic case studies, or climatological analyses using previously gridded meteorological data. Calculations may be performed sequentially on multiple meteorological grids, going from fine to coarse resolution using either archive or forecast data fields. Ai...

SEAWAT and the Sea Water Intrusion (SWI) Package for MODFLOW were used to simulate hypothetical aquifer storage and recovery (ASR) scenarios under constantand variable-density conditions. To test the codes, both models were used to represent two-dimensional axisymmetric groundwater flow near an ASR well. The models were “tricked” into representing axisymmetric flow by multiplying the input valu...

We develop a two-stage model for versioning products with respect to both vertical and horizontal attributes. At first, a firm positions its top-quality “flagship” product in a market with an imperfectly known distribution of tastes and reservation prices. In the second stage, the firm learns these consumer characteristics and has the option of extending its product line by versioning the flags...

We extend the recently proposed thermally-assisted-occupation density functional theory (TAO-DFT) [J.-D. Chai, J. Chem. Phys. 136, 154104 (2012)] to generalized-gradient approximation (GGA) exchange-correlation density functionals. Relative to our previous TAO-LDA (i.e., the local density approximation to TAO-DFT), the resulting TAO-GGAs are significantly superior for a wide range of applicatio...

recordings of ambient noise or microtremors are increasingly used to find valuable information on soil in one dimension at a given site. ambient vibrations, which are assumed to be mainly composed of surface waves, can be used to determine the surface wave dispersion curve in order to retrieve shear wave velocity profile. in this regard, microtremors are usually recorded simultaneously in an ar...

Motivated by field studies of the Ems estuary which show longitudinal gradients in bottom sediment concentration as high as O(0.01 kg/m), we develop an analytical model for estuarine residual circulation based on currents from salinity gradients, turbidity gradients, and freshwater discharge. Salinity is assumed to be vertically well mixed, while the vertical concentration profile is assumed to...

Disturbance regimes are changing worldwide, and the consequences for ecosystem function and resilience are largely unknown. Functional diversity (FD) provides a surrogate measure of ecosystem function by capturing the range, abundance and distribution of trait values in a community. Enhanced understanding of the responses of FD to measures of vegetation structure at landscape scales is needed t...

Article history: Received 7 April 2011 Received in revised form 17 September 2011 Accepted 18 September 2011 Is wind direction an adequate marker of air mass history? This review looks at the evolution of methods for assessing the effect of the origin and pathway of air masses on composition change and trends. The composition of air masses and how they evolve and the changing contribution of so...