
Water circulates continuously and seamlessly on Earth with little regard for the boundaries we draw. There are natural boundaries as between land and ocean and surface and subsurface environments, as well as human or demographic boundaries between nations, cultures, and religions...

Water circulates continuously and seamlessly on Earth with little regard for the boundaries we draw. There are natural boundaries as between land and ocean and surface and subsurface environments, as well as human or demographic boundaries between nations, cultures, and religions...