NOVELTY - A VWCP system has a compressible vessel enclosed by upper and lower covers joined by a protective seal at the edges, connected by conduit to a pressure chamber (2) into which compressible vessel discharges fluid at high water (8). Compressible vessel normally recovers the shape at low water by sucking in fluid from the pressure chamber. Closure of a valve (6) prevents contact between compressible vessel and pressure chamber so that recharge comes through the surface or surrounding waters, or both through a conduit (5) to enable driving of a turbine or dynamo (7).    USE - VWCP system for use in deep marine environment for pumping deep waters that are nutrient rich to higher levels or into atmosphere above as spray or jet to benefit aquatic biological productivity including plankton and algae in regions in which waters are vertically stratified; manipulating physical and chemical parameters such as salinity/oxygen and other gas concentrations/other mineral concentrations/temperature gradients/solids/electrolytic properties; enhancing energy and environmental efficiency of carbon capture and storage (CCS) system; enhancing oil, gas, and other mineral recovery. Uses include but are not limited to marine, estuarine, other tidal waters, lakes, rivers or other variable level water masses inland.    ADVANTAGE - Enables highly efficient use of thermal differences in the water column to drive integrated ocean thermal energy conversion or heat pump systems or both by pumping of fluids using pressure variations, thus enables much greater output of power and materials. Reduces global warming through increased marine and estuarine contribution to natural high level particulates and cloud formation, particularly as reduced classical atmospheric pollution declines and insolation increases while providing local benefits from cloud seeding, particularly in drought-afflicted zones that are increasingly desertified due to climate change. Obtains ecosystem recovery in ocean, estuaries, rivers or other masses of water of variable level by increasing recycling of nutrients for bacterial growth and aeration through expelling of spray mixed with air and/or other fluids and materials into the atmosphere or different levels in the water column. Obtains specific outcomes such as altered dissolved oxygen levels and salinity in surrounding waters or in water collected from outlets for useful purposes onsite or offsite by manipulating physical and chemical parameters such as salinity/oxygen and other gas concentrations/other mineral concentrations/temperature gradients/solids/electrolytic properties. Ensures effective integration with both closed and open circulation ocean thermal energy conversion (OTEC) system, and other forms of heat pump since VWCP systems transport fluids between different water levels and areas by entirely renewable way at minimal cost. Obtains high level of control of flow rate in multiple directions in different sections of the system, of spread of ejected and intake material, timing, mix, and quality, through the use of valves, perforated surfaces and other devices, enhanced by electronic or mechanical sensors such as pressure gauges.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of the multiple, stacked arrangement of VWCP system.    Pressure chamber (2)    Conduit (5)    Valve (6)    Turbine or dynamo (7)    High water (8)