These translated volumes contain the information that the German Naval Staff used to base their operations on. Items can range from the mundane; i.e. total number of coal cars filled, to more pertinent data, such as did the water temperature in the Mediterranean allow for the operation of midget submarines. Each diary is generally divided into five parts: Items of Political Importance, Report on the Enemy, General Situation, Submarine Situation, and Merchant Shipping. Much valuable information can be gleaned from these sources. Additional information about these records can be found here.
War Diaries, Part A, of the German Naval Staff