wind regime and sand grain size are two of the factors that determine the morphology and dynamics of sand dunes in desert areas. regarding the importance of wind effects on sand dunes especially in iran, in this study, khartooran erg was analyzed to determine wind direction and to detect sand source sites. khartooran erg is located on eastern north of iran and lies in khorasan razavi and semnan...

Barchan dunes — crescent-shaped dunes that form in areas of unidirectional winds and low sand availability — commonly display an asymmetric shape, with one limb extended downwind. Several factors have been identified as potential causes for barchan dune asymmetry on Earth and Mars: asymmetric bimodal wind regime, topography, influx asymmetry and dune collision. However, the dynamics and potenti...

Accurate short-term wind forecasts (STWFs), with time horizons from 0.5 to 6 hours, are essential for efficient integration of wind power to the electrical power grid. Physical models based on numerical weather predictions are currently not competitive, and research on machine learning approaches is ongoing. Two major challenges confronting these efforts are missing observations and weather-reg...

We present a cascade model for turbulence in weakly collisional plasmas that follows the nonlinear cascade of energy from the large scales of driving in the MHD regime to the small scales of the kinetic Alfvén wave regime where the turbulence is dissipated by kinetic processes. Steady-state solutions of the model for the slow solar wind yield three conclusions: (1) beyond the observed break in ...

Barchan dunes — crescent-shaped dunes that form in areas of unidirectional winds and low sand availability — commonly display an asymmetric shape, with one limb extended downwind. Several factors have been identified as potential causes for barchan dune asymmetry on Earth and Mars: asymmetric bimodal wind regime, topography, influx asymmetry and dune collision. However, the dynamics and potenti...

High latitude ocean gateway changes are thought to play a key role in Cenozoic climate evolution. However, the underlying ocean dynamics are poorly understood. Here we use a fully coupled atmosphere-ocean model to investigate the effect of ocean gateway formation that is associated with the subsidence of the Greenland-Scotland Ridge. We find a threshold in sill depth (∼50 m) that is linked to t...

Results from a wind tunnel model of the sheared atmospheric convective boundary layer (CBL) are presented and discussed. The model is realized in the thermally stratified wind tunnel of the Institute of Hydrology and Water Resources Planning (IHW), University of Karlsruhe. Design of the wind tunnel, and the technique employed for velocity and temperature measurements are described. The performe...

The Adriatic Sea, as adjacent sea of the greater Mediterranean Sea, is under direct influence of atmospheric processes and their variability. Cold deep water formed under strong winter outbursts of Bura wind in the Northern Adriatic plays crucial role in the overall Adriatic circulation. Interannual variability of temperature and salinity in the Adriatic Sea is firstly interplay of Northern Adr...

Active wind noise detection and suppression techniques are a new and essential paradigm for enhancing ASR-based functionality with smart glasses, in addition to other wearable and smart devices in the broader IoT (Internet of things). In this paper, we develop two separate algorithms for wind noise detection and suppression, respectively, operational in a challenging, low-energy regime. Togethe...

Rapidly rotating magnetic neutron stars in eccentric binary systems containing an early type star provide a unique opportunity to investigate the interplay between radio pulsar, stellar wind and accretion phenomena. We summarise the radio pulsar-dominated and the accretiondominated regimes, discussing how the transition from one regime to another can take place as a result of the varying orbita...