Low-pressure area area of wind divergence aloft occurs ahead of embedded shortwave troughs, which are of smaller wavelength. Diverging winds aloft ahead of these troughs cause atmospheric lift within the troposphere below, which lowers surface pressures as upward motion partially counteracts the force of gravity. Thermal lows form due to localized heating caused by greater sunshine over deserts and other land masses. Since localized areas of warm air are less dense than their surroundings, this warmer air rises, which lowers atmospheric pressure near that portion of the Earth's surface. Large-scale thermal lows over continents help drive monsoon circulations. Low-pressure areas can also
High pressure metamorphic terranes along the Bangong-Nujiang Suture Zone High pressure metamorphic terranes along the Bangong-Nujiang Suture Zone High pressure terranes along the ~1200 km long east-west trending Bangong-Nujiang suture zone (BNS) on the Tibetan Plateau have been extensively mapped and studied. Understanding the geodynamic processes in which these terranes are created is key to understanding the development and subsequent deformation of the BNS and Eurasian deformation as a whole. With an average elevation of just above 5,000 m, the Tibetan Plateau is the largest elevated region on Earth. Explaining how such a large area (2.5 million km) can have such high elevations has perplexed geologists for some time.