Satellites are ideal for observing the global environment as they are capable of revealing and monitoring remote environments, hidden features, and even events that the human eye cannot detect. They provide reliable data 24 hours a day, seven days a week on the following atmospheric phenomena that are essential for weather forecasting:
Temperature, wind speed and direction, aerosols, water vapour, cloud cover, precipitation, storms, and tropical cyclones. Satellites can also monitor how winds disperse smoke from wildfires or ash from volcanic eruptions.
Satellites provide the following data on the oceans:
Sea surface temperature, sea level height, ocean currents, and ocean winds. It is also possible to monitor accidents, such as large oil spills, and periodic oscillations in the sea that affect global weather patterns, such as El Niño in the Pacific Ocean.
The following land features can also be observed via satellites:
Land surface temperature, winds, vegetation cover, bodies of water, human settlements, soil moisture, depth and extent of snow and ice.
Satellites can be owned and operated by government agencies, international organizations, or by the private sector. One of the most advanced polar-orbiting commercial satellites, the GeoEye-1, provides images with a resolution of 0.5 metres.