Rainfall depends on the hydrological cycle, where the sun heats land and sea unevenly to cause wind. During the day, the land heats faster than the sea and warm air rises upward from land. The movement of the air causes cooler air to move from over the sea toward land. The classical theory holds that oceanic winds pick up moisture and humidity far offshore, especially from ocean spray generated by powerful winds at sea. As well, winds pick up much moisture along coastal regions from the spray from waves that break at or near the coast and that may evaporate from the warmer land surface.
In several regions internationally, variations in surface temperature produce cyclones that sometimes occur over warm water and become waterspouts. Waterspouts have been observed to form on Lake Michigan and Lake Ontario, including during winter months where the swirling wind picks up snow from the lake surface and is known as a snow devil. Snow devils have been observed to carry a massive volume of snow from the lakes to inland locations. Louis Michaud's research suggests that is may be possible to purposefully create the necessary conditions that would produce a swirling mass of air directly above water.
The swirling mass of air would create a spray of seawater at specially chosen stationary locations along the oceanic coast, then carry the spray to higher elevation where much of it would evaporate during warmer weather and through sublimation during periods of extreme dryness. Gravity would cause the higher salinity brine to fall back to the sea. Brine that falls on coastal land would undergo further evaporation and leave deposits of sea salt on the beaches. During the day, prevailing winds would carry the resulting humidity inland to watershed regions located at the higher elevations.
Most North American coastal areas have access to 2-renewable sources of thermal energy: concentrated solar thermal energy and deep level low-grade geothermal energy. The 3rd option would be to source thermal energy from the waste heat from a seawater-cooled nuclear thermal power station. One means by which to access low-grade geothermal energy would be to drill into the earth bedrock at some 1500 offshore islands along the west coast of Quebec and similar offshore islands along the coasts of British Columbia,
Advances in the mining and exploration industries have developed methods by which to drill to great depths in the earth's bedrock and access low-grade geothermal energy that lies below the surface of most offshore islands. That technology may also be able to access deep level pockets of gravel and porous rock that occur in the bedrock that may then become saturated with seawater. There may be sufficient deep level geothermal energy at near 100°C that may heat the seawater that trickles to down to the lower elevations. That heated seawater would become the thermal energy source that could drive a waterspout generator.
The construction of a waterspout generator would comprise a tower built over a pond of heated seawater, perhaps at a purposefully excavated oceanic inlet. Angled air inlets built into the base of the tower would initiate the swirling movement of heated air that would rise upward from above the heated seawater. A submerged heat exchanger installed in the pond at the base of the generator or in the channel leading to it, would transfer heat into the seawater. Air directly above the heated pond would pick up heat and begin to rise upward.
As the heated air rises upward, replacement air would flow in through the angled air inlets at the base of the tower and swirl over the pond of heated seawater. It may also be preheated by ambient solar heat on the ground and surrounding water surface prior to flowing into the waterspout generator. Heat from the pond surface would accelerate the incoming swirling mass of air, producing small waves on the heated pond along with a spray of heated water. That swirling spray would form into a waterspout that would swirl upward into the atmosphere.
Much of the moisture in the swirling mass of spray would evaporate at higher elevation. Gravity would cause the high salinity brine to drop either into the sea or on to coastal land. Prevailing winds may carry evaporated moisture from the spray inland to the higher elevations where it may condense in the cooler air or on purposefully installed dew fences located over valleys. Much of the evaporated moisture produced by waterspout generators may occur as rain over the watershed regions of storage dams of Hydro Quebec, BC Hydro and several other hydroelectric utilities.
Coastal winds would carry evaporated moisture from the waterspout spray and inland toward coastal mountains, where naturally occurring precipitation would add water to the hydroelectric reservoirs. There may be scope to install waterspout generators along the west coasts of Quebec and Mexico, where high salinity brine may fall to the earth along the desolate coastline while coastal winds carry the evaporated moisture inland. The installation of waterspout technology at various coastal locations around North America has the potential to create very highly localized micro-climatic zones.
However, the need for potable water may leave little alternative other than to develop such zones. Microclimates created by purposefully built waterspout generators may provide water for human consumption and for hydroelectric power generation, instead of a possible drought that may otherwise occur. Both Hydro Quebec and BC Hydro have indicated their interest in exporting additional hydroelectric power into American markets. The use of waterspout generators may enhance their ability to so in the future and especially during summer drought conditions.