[1] We use one-and two-limb single-pass models to de termine vent field characteristics such as mass flow rate Q, bulk permeability in the discharge zone k d , thickness of the conductive boundary layer at the base of the system d, magma replenishment rate, and residence time in the discharge zone. Data on vent temperature, vent field area, heat output, and the surface area and depth of the subaxial magma chamber (AMC) constrain the models. The results give Q~100 kg/s, k d~1 0 À13 m 2 , and d~10 m, essentially independent of spreading rate, and detailed characteristics of the AMC. In addition, we find no correlation between heat output at individual vent fields and spreading rate or depth to the AMC. We conclude that high-temperature hydrothermal systems are driven by local magma supply rates in excess of that needed for steady state crustal production and that crustal permeability enables hydrothermal circulation to tap magmatic heat regardless of AMC depth. Using data on partitioning of heat flow between focused and diffuse flow, we find that 80-90% of the hydrothermal heat output is derived from high-temperature fluid, even though much of the heat output discharges as low-temperature fluid. In some cases, diffuse flow fluids may exhibit considerable conductive cooling or heating. By assuming conservative mixing of diffuse flow fluids at East Pacific Rise 9 50 0 N, we find that most transport of metals such as Fe and Mn occurs in diffuse flow and that CO 2 , H 2 , and CH 4 are taken up by microbial activity.

2014: Submeso motions within the stable boundary layer and their relationships to local indicators and synoptic regime in moderately complex terrain. ABSTRACT 22To better understand the physical processes of the stable boundary layer (SBL) and to 23 quantify submeso motions in moderately complex terrain, we perform exploratory case-study 24 analyses using observational field data supplemented by gridded North American Regional 25 Reanalysis (NARR) data and Penn State University (PSU) Realtime Weather Research and 26 Forecasting (WRF) model output. Submeso motions are nominally defined as all motions 27 between the largest turbulent scales and the smallest mesoscales. Seven nighttime cases from 28 August and September 2011 are chosen from our Rock Springs (RS), central Pennsylvania 29 network of eight ground-based towers and two sound detection and ranging (sodar) systems. The 30 observation network is located near Tussey Ridge, and ~15 km southeast of the Allegheny 31 Mountains. 32The seven cases are classified by the dominant synoptic flow direction and proximity to 33 terrain to assess the influence of synoptic conditions on the local submeso and mesogamma 34 motions. We find that synoptic winds with a large crossing angle over nearby Tussey Ridge can 35 generate mesogamma wave motions and larger magnitude submeso temperature and wind 36 fluctuations in the RS network than winds from the direction of the more distant Allegheny 37Mountains. Cases with synoptic winds that are nearly parallel to the topographic contours or 38 generally weak exhibit the smallest fluctuations. We also analyze the change in the magnitude of 39 near-surface submeso temperature and wind fluctuations to local indicator variables. The 40 observed submeso wind and temperature fluctuations are generally larger when low-level wind 41 speed and thermal stratification, respectively, are greater, but the synoptic flow and its relation to 42 the terrain also play an important role. 43

Descriptions of the experimental design and research highlights obtained from a series of four multiagency field projects held near Cape Canaveral, Florida, are presented. The experiments featured a 3 MW, dual-polarization, C-band Doppler radar that serves in a dual capacity as both a precipitation and cloud radar. This duality stems from a combination of the radar’s high sensitivity and extremely small-resolution volumes produced by the narrow 0.22° beamwidth and the 0.543 m along-range resolution. Experimental highlights focus on the radar’s real-time aircraft tracking capability as well as the finescale reflectivity and eddy structure of a thin nonprecipitating stratus layer. Examples of precipitating storm systems focus on the analysis of the distinctive and nearly linear radar reflectivity signatures (referred to as “streaks”) that are caused as individual hydrometeors traverse the narrow radar beam. Each streak leaves a unique radar reflectivity signature that is analyzed with regard to estimating the underlying particle properties such as size, fall speed, and oscillation characteristics. The observed along-streak reflectivity oscillations are complex and discussed in terms of diameter-dependent drop dynamics (oscillation frequency and viscous damping time scales) as well as radar-dependent factors governing the near-field Fresnel radiation pattern and inferred drop–drop interference.