Definition of downwelling in US English:



  • The downward movement of fluid, especially in the sea, the atmosphere, or deep in the earth.

    • ‘Those upwellings and downwellings imply that at the surface there is a general southward wind between 0 and 30 lat, a northward wind between 30 and 60 lat, and a southward wind between 60 and 90 lat.’
    • ‘One interpretation is that the ‘fast’ regions are simply colder downwellings and that slow regions are hotter upwellings in a compositionally homogeneous mantle.’
    • ‘In contrast, brachyuran zoeae in nearsurface waters would descend at the coast during downwelling and, together with larvae aloft nearshore sediments, be transported seaward below the thermocline.’
    • ‘One possible explanation would be downwelling of dry air, which is also consistent with deeper clouds observed at the southern pole.’
    • ‘The centers of anticyclonic, warm-core ocean eddies typically are zones of downwelling and therefore are nutrient-deficient.’
    • ‘Local upwelling and downwelling of the upper halocline cause fluctuating baroclinic currents during renewal, but these seem to have little influence on the average volume flux of new deep water.’
    • ‘‘That slows down the whole pattern of currents that lead to upwelling in some regions and downwelling in others… we can speculate that this nutrient supply by the Southern Ocean would also slow down,’ he said.’
    • ‘Convergence of these fronts led to downwelling of surface waters and upwelling of deep waters during the stratified period.’
    • ‘Rocky intertidal communities on opposite sides of the south island experience contrasting oceanographic conditions (intermittent upwelling on the west coast, persistent downwelling on the east coast).’


  • Characterized by or undergoing downwelling movement.

    ‘downwelling mantle’
    • ‘Stratospheric ozone depletion increases downwelling radiation, particularly in the UV-B portion of the spectrum.’
    • ‘We have combined measured coral reflectance and fluorescence spectra with modeled downwelling spectral irradiances to investigate the contribution of fluorescence to coral spectra and color.’
    • ‘Counterilluminating species must cope with the changes in the angular distribution and spectra of downwelling light at different depths.’
    • ‘To verify the library, computed upwelling radiance and downwelling irradiance spectra were compared to field measurements obtained with a hyperspectral tethered spectral radiometer buoy.’
    • ‘The model was more sensitive to leaf orientation than leaf optical properties, seabed reflectance, or the average cosine of downwelling irradiance.’
    • ‘Therefore, the bioluminescence and activity of the prey needs to be taken into consideration, in addition to downwelling illumination, when examining the light environment of marine organisms.’
    • ‘These factors are coupled with a very high snow albedo: under fresh snow surface conditions, about 90% of the incoming downwelling irradiance is reflected upwards while, in the case of old snow coverage, the UV albedo is about 0.6.’
    • ‘On the sediment scale, microbial activity increased with both upwelling and downwelling Darcian velocities of interstitial water and was minimal when the surface/subsurface water exchange decreased.’
    • ‘In such instances, a rigid coupling of plates to convection cells would imply the unusual scenario of upwelling along an expanding ring, with a downwelling column inside it.’
    • ‘When zooplankton swim upward against such a downward current, they form patches as more and more individuals are brought in with the horizontal currents and concentrated in the downwelling zone.’
    • ‘In this model run, anoxia is triggered by halving the O2 content of the downwelling water.’
    • ‘The beds showing progressive vertical transition from parallel to ripple lamination also reflect combination of storm waves and downwelling sediment-laden currents.’
    • ‘Anoxia is then triggered at t = 0 by reducing the oxygen concentration in the downwelling water by 50%.’
    • ‘As the spectral distribution narrows with depth, the angular distribution of the downwelling light broadens.’
    • ‘Ambient light at mesopelagic depths consists of dim, nearly monochromatic, and primarily downwelling solar radiation.’
    • ‘Weak downwelling conditions were prevalent for the next several days, and the Columbia River plume returned to the coast where it mixed with the chlorophyll-enriched waters in the nearshore before entering the estuary.’