Clouds - Real-time
Geostationary infrared satellite images are used by meteorologists to determine where clouds are, but more importantly, how the clouds are moving. The infrared, IR, satellites work by measuring the infrared radiation that is emitted. Because the emitted radiation is proportional to temperature, the data are converted to temperature values, which can be useful for meteorologists. In comparison to clouds, the Earth's surface, even on very cold nights, is warm. When there are clouds, they absorb the radiation emitted by the Earth below and emit their own radiation at a much cooler temperature. Any area that has clouds shows up cooler than the ground, allowing meteorologists to detect the locations of the clouds. The height of clouds is inversely proportional to temperature, meaning that the tallest clouds are the coldest. It is often the tallest clouds that bring the most severe weather.
The satellites that collect these data are geostationary, meaning that they rotate at the same rate as the Earth so that the satellites are over the same spot on Earth all the time. This allows them to collect a continuous stream of data for one location so that "movies" of the data can be made. Over the United States there are two such satellites, the GOES (Geostationary Operational Environmental Satellites) - East and GOES-West. There are many such satellites worldwide. This dataset is a composite of GOES, Meteosat, and MTSat satellite data. Meteosat and MTSat are similar to GOES, but are operated by other countries. This real-time dataset is shaded on a gray scale, meaning that the lowest clouds are a very light gray and the highest clouds are bright white. The "Blue Marble" is the background image for this dataset. Data for this visualization is available for the past thirty days. In addition to this dataset, Real-time: Color Enhanced Infrared Satellite, illustrates the real-time, color enhanced, location and movement of clouds based on data gathered by the GOES, Meteosat, and MTsat satellite data.
- Lowest clouds light gray and highest clouds bright white
- Available in real-time