Obviously I am unaccustomed to the waters of Hacker News. I meant to post this in response to nkurz's question rather than the main thread. See below. Hi, I'm

Obviously I am unaccustomed to the waters of Hacker News. I meant to post this in response to nkurz's question rather than the main thread. See below. Hi, I'm Tom, the other cofounder at Tule. I developed the recent improvements in Surface Renewal during my PhD work at UC Davis. Examples of scalars, as the term is used in atmospheric science, are air temperature, water vapor concentration, carbon dioxide concentration, or any other constituent of the atmosphere. Here is a more formal definition from http://glossary.ametsoc.org/wiki/Scalar http://glossary.ametsoc.org/wiki/Scalar: Any physical quantity with a field that can be described by a single numerical value at each point in space. A scalar quantity is distinguished from a vector quantity by the fact that a scalar quantity possesses only magnitude, whereas a vector quantity possesses both magnitude and direction. Thus, pressure is a scalar quantity and velocity is a vector quantity.