How it's made: Weather Satellite: How the View from Above Helps to Create the Forecast

This is the penultimate blog post covering Category One: Weather Observations in the How It’s Made series. We’ve already covered weather stations and radar; today we’ll be focusing on weather satellites.

The 20-part How It’s Made series explores the Five Categories that create an accurate, reliable forecast. Each article is a stand-alone story, but together they explain precisely how the Five Categories tie together to take a weather forecast from good to great.

 

Download your copy of "How It’s Made: The Ultimate Guide to Weather Forecasting" below:


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Weather satellites monitor the conditions of the atmosphere, clouds, and the Earth’s surface. Images are taken either in the infrared spectrum, which allows cloud coverage to be observed at all time; or in the visible spectrum, which requires daylight but provides a more realistic visualization.

 

There are two types of satellites: Geostationary satellites and polar orbiting satellites. The difference comes down to the way they orbit the Earth. Geostationary satellites follow the direction of the Earth’s orbit, which means that they’re always located above the same point on Earth. Polar orbiting satellites circle around the two poles.

 

The most important satellites are geostationary. They’re located 35,786km above the equator and deliver images every 5 to 15 minutes, with a spatial resolution of 1 to 6km. The polar orbiting satellites have a lower earth orbit and can provide images with a higher spatial resolution (under 1km) than geostationary satellites. However, they can only deliver 1 or 2 images each day, which means they’re typically for specific use cases only.

 

What data is available from satellite?

 

“With satellite data, we get a complete overview of the current weather pattern on a global scale. This helps us to provide an excellent forecast for remote places on land and over the ocean.”

Marco Radke-Fretz,

Data Manager (Data Provisioning)
MeteoGroup

 

Weather experts purchase and process satellite data. As the most important satellites are geostationary, data is required from multiple sources to create a global view including:

For Europe, Africa, and the Indian Ocean: Images in different spectral wavelengths from Eumetsat’s Meteosat satellites.

For Asia: Images from the Japan Aerospace Exploration Agency’s Himawari satellite.

For North and South America and the Pacific Ocean: Images from NOAA’s two satellites – GOES-East and GOES-West.

 

Data is enhanced with images from the polar orbiting satellites (including Metop-A, Metop-B (from Eumetsat), NOAA-19, Aqua and Terra (from NOAA and NASA)) and also derived satellite data. This including cloud analysis images, global rainfall estimates, precipitation rate at ground level and sea ice data.

When required, this data can be further enhanced with additional data sources, such as:

● Open data, for example, the data gathered by the polar orbiting satellites of EU’s Copernicus project (Sentinel-1, -2 and -3)

● Geostationary satellite data from China and Russia (this is especially relevant for coverage in Asia)

● Derived data from satellites; for example, solar radiation and precipitation data
 

How do weather experts improve the data to create a forecast?

 

Weather experts will process the satellite data, using their own satellite data-processing system, and combine data from multiple satellite sources to create a global view on an hourly basis.

They also integrate it with data from other observation sources, to provide a complete picture of what is happening, and enhance the satellite data through temporal interpolation to improve the temporal resolution.

Alongside this, they can provide satellite data for any customer-specific, weather satellite-related needs and offer a range of visualization capabilities, for example:

○ Customized combinations of images from the different spectral wave lengths to visualize special atmospheric or weather features (like fog at night or dust)

○ A combination of precipitation and model data to create precipitation type images

○ Visualizing clouds on the whole globe using the global composite

○ Creating smooth, custom, cloud animations with interpolated satellite images

○ Visualizing cloud images together with other data in layer-based visualization tools

○ Visualizing satellite-derived precipitation images with information about precipitation type

 

Weather satellite help minimize weather-related risk for businesses
 

Satellite data can help forecasters support businesses and industries in many ways. In particular, it’s beneficial for monitoring thunderstorms and predicting squalls - short, heavy bursts of weather that result in the rapid onset of near to zero visibility and strong gusty winds. Knowing when squalls will occur is critical for offshore companies, energy production, and shipping because they have a significant impact on operations.

 

Download your copy of "How It’s Made: The Ultimate Guide to Weather Forecasting" below:


Download Now

 

With satellite data, we get a complete overview of the current weather pattern on a global scale. This helps us to provide an excellent forecast for remote places on land and over the ocean.


Marco Radke-Fretz


Data Manager (Data Provisioning)
MeteoGroup