ADVECTIVE PRECIPITATION

In December of 1993, I was invited to lecture at the National Institute of Hydrology, in Roorke, India. My presentation was titled "Management of floods and droughts in semiarid regions." One of the topics covered was Budyko's hydroclimatological model of a coupled land surface-atmosphere system.

The main feature of Budyko's model is the separation of precipitation into its advective and evaporative components. A key step is the quantification of the water vapor advected into the control volume.

At the end of the lecture, one of the participants confided to me: "Prof. Ponce, I have been in the field of hydrology for about ten years, and have never heard anybody talk about advective precipitation."

In fact, advective is a term that belongs to fluid mechanics, and, in our context, to hydroclimatology. Yet in hydrology it is largely unknown. In its path, the hydrologic cycle crosses a gamut of fields of knowledge, including oceanography, meteorology, climatology, hydrology and hydraulics, each with its own vocabulary. Needless to say, this diversity of terminology contributes to make the holistic view of science all the more challenging.

 

Sunset at Calangute Beach, Goa, India.