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Geolens

Glossary

417 words used in the labs.

Find a term from the labs, understand the process behind it, and see how it appears in the landscape. Each entry connects an explanation with a real observation and a model you can explore.

Term

Convergence

The movement of air towards an area, bringing neighbouring flows together. Near the surface it can encourage rising air, cloud and rain if enough moisture is present. Convergence describes a flow pattern; it is not itself a type of cloud.

What to look for

Aqua MODIS observed Cyclone Evan near Fiji on 16 December 2012. Its cloud bands spiral around the centre; a mathematical logarithmic spiral is an approximation, not a measured exact fit.

Related labs

Cyclone and anticyclone →
Cyclone Evan's spiral cloud bands cross the islands of Fiji in a NASA satellite image.
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Explore further with USGS water glossary · USGS volcano glossary · NPS glacial geology · NASA Earth facts. Photograph acknowledgements are collected on the Image credits page.