#solar radiation

• Actinograph — A structural meteorological instrument utilized for the continuous and automatic graphical recording of the intensity of direct and diffuse solar radiation onto a special chart called an actinogram. The device operates based on a bimetallic or thermoelectric system sensitive to temperature variations induced by solar rays, transmitting the mechanical movement to a recording arm with a pen that traces the radiant values curve onto a rotating drum.
• Actinogram — A printed chart or continuous graphic curve automatically recorded by an actinograph, representing the variations in solar radiation intensity (both direct and diffuse) as a function of time over the course of a day. This structural technical sheet serves as a reference document in meteorological stations for calculating the Earth's energy balance, monitoring local climate evolution, and determining a region's solar insolation level.
• Actinometer — A structural meteorological and physical instrument utilized for measuring the intensity of radiant energy, specifically direct solar radiation. The device operates based on the absorption of rays by an ideal black body, converting luminous energy into heat, which is subsequently determined via thermoelectric or bimetallic methods, or by directly evaluating light-triggered photochemical reactions over a fixed time interval.
• Albedometer — A precision meteorological instrument consisting of two coupled pyranometers (one facing upward and one downward), used for the direct measurement of a surface's albedo by simultaneously determining global solar radiation and that reflected by the ground.
• Antisolar — Located in a position diametrically opposite to the Sun with respect to an observer or a reference body; situated at the central point of the Earth's shadow. In a modern technological context, the term describes protective devices, screens, or chemical treatments designed to block, reflect, or neutralize intense solar radiation or glare.