Stratosphere Stratosphere The stratosphere () is the second major layer of Earth's atmosphere, just above the troposphere, and below the mesosphere. The stratosphere is stratified in temperature, with warmer layers higher and cooler layers closer to the Earth; this increase of temperature with altitude is a result of the absorption of the Sun's ultraviolet radiation by the ozone layer. This is in contrast to the troposphere, near the Earth's surface, where temperature decreases with altitude. The border between the troposphere and stratosphere, the tropopause, marks where this temperature inversion begins. Near the equator, the stratosphere starts at as high as ,
Solar Radiation and Climate Experiment Solar Radiation and Climate Experiment The Solar Radiation and Climate Experiment (SORCE) is a NASA-sponsored satellite mission that measures incoming X-ray, ultraviolet, visible, near-infrared, and total solar radiation. These measurements specifically address long-term climate change, natural variability and enhanced climate prediction, and atmospheric ozone and UV-B radiation. These measurements are critical to studies of the Sun, its effect on our Earth system and its influence on humankind. The SORCE spacecraft launched on January 25, 2003 on a Pegasus XL launch vehicle to provide NASA's Earth Science Enterprise (ESE) with precise measurements of solar radiation. SORCE measures the Sun's output using