Ozone layer breakdown of ozone in the stratosphere results in reduced absorption of ultraviolet radiation. Consequently, unabsorbed and dangerous ultraviolet radiation is able to reach the Earth’s surface at a higher intensity. Ozone levels have dropped by a worldwide average of about 4 percent since the late 1970s. For approximately 5 percent of the Earth's surface, around the north and south poles, much larger seasonal declines have been seen, and are described as "ozone holes". The discovery of the annual depletion of ozone above the Antarctic was first announced by Joe Farman, Brian Gardiner and Jonathan Shanklin, in a paper which appeared
Layer Jump Recording in their software. Layer Jump Recording Layer Jump Recording (LJR) is a writing method used for DVD-R DL (Dual Layer). It permits recording the disc per increments called session (see Optical disc authoring), a.k.a. multi-session. It also permits a faster closing of the disc by saving extraneous padding when the amount of recorded data does not fill-up the disc. It overcomes these limitations of Sequential Recording (SR), the writing method usually applied to write-once optical media. The layer jump is a switch (jump) between the layer closer to the laser head (referred as L0) to the farther layer (referred as