The essence of the Water-Energy-Biomass (WEB) Nexus is that (the Sun’s) Energy drives the biochemistry of photosynthesis to create Biomass. Water is the medium of biochemistry, so Water is the fulcrum of the WEB Nexus.
Depending on the state of that biomass; coal, zooplankton, corn or corned beef, it can be utilized to produce heat, catfish, beef, cream or human beings.
The Sun initiates the Water Cycle by causing evaporation of sea water to form clouds, creating temperature and pressure differentials that cause winds to blow the clouds over land where they deposit clean freshwater as rain to flow into rivers that ultimately flow back into the sea. This effect of the Sun’s Energy is what we call “weather” in the short term, locally and “climate” in the longer term, globally.