What is the Bergeron Process?
The ‘Bergeron Process’ is an in-cloud process where Q is formed before it falls out of the clouds as snow or rain. This process was discovered by Swedish meteorologist Tor Bergeron in the 1930’s. The process starts off with tiny microscopic ice crystals that begin to grow at the expense of available moisture, super-cooled water droplets (water in its liquid form at below freezing temperatures). As the crystals grow into larger snowflakes they begin to fall and collide with other snowflakes eventually falling out of the cloud as Q. If it is cold enough, as it is in winter, the Q will remain as snow. In the summer the process remains the same but the snowflakes melt into raindrops as they descend.
The Bergeron Process (often referred to in meteorology as the Bergeron-Findeisen process) describes the primary way that precipitation is formed inside a cloud which contains a mixture of ice crystals and water droplets. It is also referred to as the cold rain or ice crystal process. Swedish meteorologist Tor Bergeron helped discover this process in the 1930s. Inside a cloud with sufficiently cold temperatures (usually less than -10C), ice crystals grow larger at the expense of super-cooled water droplets which evaporate. Through this preferential development, ice crystals can become large enough to begin falling, colliding with other crystals, and eventually fall out of the cloud.
