The variation of wind-optimal transatlantic flight routes and their turbulence potential is investigated to understand how upper-level winds and large-scale flow patterns can affect the efficiency and safety of long-haul flights. In this study, the wind-optimal routes (WORs) that minimize the total flight time by considering wind variations are modeled for flights between John F. Kennedy Intern...

A model of surface waves generated on deep water by strong winds is proposed. A two-layer approximation is adopted, in which a shallow turbulent layer overlies the lower, infinitely deep layer. The dynamics of the upper layer, which is directly exposed to the wind, are nonlinear and coupled to the linear dynamics in the deep fluid. The authors demonstrate that in such a system there exist stead...

Our long-term goal is unchanged from last year. It is to learn how to predict the cloudiness, entrainment rate, and turbulent fluxes in the marine boundary layer under any and all large-scale conditions. In particular the effects of varying sea surface temperature, varying inversion strength, and varying mean winds must be included. The cloudiness types encompassed include fog, stratus, stratoc...

In fragmented tropical landscapes, among the most pervasive causes of ecological change are edge effects diverse ecological alterations associated with the abrupt, artificial boundaries of forest fragments (Laurance & Bierregaard 1997, Lovejoy et al. 1986, Turner 1996). A striking edge effect in fragmented Amazonian forests is chronically elevated tree mortality (Ferreira & Laurance 1997, Laura...

We have used MERLIN, at 1.4 and 5 GHz, to search for radio supernovae (RSNe) and supernova remnants (SNRs) in the unobscured irregular dwarf galaxy NGC1569, and in particular in the region of its super star clusters (SSCs) A and B. Throughout NGC1569 we find some 5 RSNe and SNRs but the SSCs and their immediate surroundings are largely devoid of non-thermal radio sources. Even though many massi...

Urban areas which are situated at the intersection of Alpine valleys are submitted to complex atmospheric flow patterns with significant impact on air quality. Local dynamics develop systems of slope and valley winds which interact ones with the others. Pollutants evolve according to chemical reactions homogeneously as gases and heterogeneously with particulate matters .There is a growing conce...

The use of wind power for generating electricity has experienced an uninterrupted and accelerating growth over last few decades and this growth is likely to continue. In order to enable even greater role of wind energy in power production it is necessary to increase the size and unit power of wind turbines. As wind turbines grow in size they are subjected to extreme loads and fatigue caused by ...

Doppler spectra taken with the VHF Doppler radar at White Sands Missile Range are used to describe the winds and turbulence for 10 days in March-April 1991. The large power aperture product of this radar provides excellent data coverage in 150-m layers over the entire height range used, about 5-20 km. The results show that gravity-wave activity and small-scale turbulence are significantly enhan...

Vector surface turbulent stresses are estimated from vector winds determined from space-borne scatterometers. Scatterometer vector winds differ subtly from in situ observations of vector winds. These differences are exaggerated for severe storm conditions, which is advantageous for determining surface stress. A physically based model for surface stress is developed to link surface turbulent str...

[1] Probability distribution and power density of wind speed over global oceans are computed from eight years of QuikSCAT measurements. They describe the variation and higher moments of wind speed that are critical in relating the non-linear effects of wind on electric power generation capability, shipping hazard, and air-sea exchanges in heat, water, and greenhouse gases. The power density dis...