Color Color Color (American English), or colour (Commonwealth English), is the characteristic of human visual perception described through color "categories", with names such as red, orange, yellow, green, blue, or purple. This perception of color derives from the stimulation of cone cells in the human eye by electromagnetic radiation in the visible spectrum. Color categories and physical specifications of color are associated with objects through the wavelength of the light that is reflected from them. This reflection is governed by the object's physical properties such as light absorption, emission spectra, etc. By defining a color space, colors can be identified numerically
Forel-Ule scale Vol 5 (2010), ) and can be seen as a simple but adequate scale to classify the color of rivers, lakes, seas and oceans. The Forel-Ule observations belong, besides temperature, salinity and Secchi depth, to the oldest oceanographic parameters dating back to 1890. Forel-Ule scale The Forel-Ule Scale is a method to approximately determine the color of bodies of water, used in limnology and oceanography. By means of mixing different chemical (The standard solutions are made with distilled water, ammonia, copper sulphate, potassium-chromate and cobalt-sulphate) a standard color scale is produced in a series of numerically designated vials (1-21) which