BIO205H5 Chapter Notes - Chapter 2: Photosynthetically Active Radiation, Shortwave Radiation, Atmospheric Pressure
Document Summary
2. 1 earth intercepts solar radiation solar radiation from sun travels as stream of photon/packets of energy (behave as either waves/particles) All objects emit radiant energy (nature of energy emitted depends on temperature of object. Earth emits more longwave radiation than absorbs solar radiation b/c sun rad only recieved during day and earth rad emitted day + night. Greenhouse effect =rad8n emitted by earths surface trapped by co2 in atmosphere and clouds and sent back to surface. important for maintaining earth"s temperature. Visible light =wavelengths 400 - 700nm: known as photosynthetically active radiation (par) Amount of solar radiation intercepted varies w/ latitude (two factors: higher latitude = steepr angle of radiation hitting surface, radiation travelling thru steep angle must go thru deeper layer of air. Process = radiation hits >particles in the air = >rad reflected back into space. Atmospheric/ air pressure = amt of force by air exerted over given surface area.
