Satellite earth view atmosphere

Satellite image showing Earth's atmosphere from a global perspective, highlighting clouds and atmospheric phenomena.

About this subject

Satellite observation of Earth's atmosphere is essential for meteorology, climatology, and environmental monitoring. Geostationary satellites, such as the GOES series (USA) and Meteosat (Europe), orbit at 36,000 km altitude and provide continuous images of a hemisphere, allowing tracking of storms, cold fronts, and cyclones. Polar-orbiting satellites, like NOAA-20 and Suomi NPP, pass over the poles and map the entire planet in swaths, offering high-resolution data on cloud cover, temperature, and atmospheric composition.

The atmosphere has five main layers: troposphere (where weather occurs), stratosphere (with the ozone layer), mesosphere, thermosphere, and exosphere. Satellite images typically focus on the troposphere, capturing various cloud types, cumulus, stratus, cirrus, and patterns such as cold fronts and hurricanes. Satellite data is also used to measure air pollution, including aerosol levels and nitrogen dioxide, through sensors like MODIS and TROPOMI.

Historically, the first weather satellite, TIROS-1, was launched in 1960. Since then, technology has evolved to multispectral and hyperspectral imaging, enabling the identification of trace gases and vertical temperature profiles. The Brazilian satellite program, with CBERS (a China-Brazil partnership), also contributes to monitoring the Amazon and regional climate. Combining satellite data with numerical weather prediction models has revolutionized short- and medium-term forecast accuracy, saving lives and protecting the economy.

Frequently Asked Questions

What is the difference between geostationary and polar-orbiting satellites?

Geostationary satellites remain fixed over one point on Earth and capture continuous images of the same hemisphere, ideal for storm monitoring. Polar-orbiting satellites circle from north to south and cover the entire planet in swaths, offering higher resolution and detailed global data.

How do satellites measure air pollution?

Sensors like MODIS (Terra/Aqua) and TROPOMI (Sentinel-5P) detect specific wavelengths absorbed by pollutant gases and aerosols, generating concentration maps of nitrogen dioxide, tropospheric ozone, and fine particulate matter.

What are visible and infrared satellite images?

Visible channel images show sunlight reflected by clouds and the surface, working only during daytime. Infrared images record thermal radiation emitted, allowing clouds and temperatures to be seen both day and night.