Unsung Heroes Of Meteorology : Tor BergeronAdded : Thursday at 13:15 Today, we take a look back in time to a Swedish scientist who went above and beyond the call of duty and discovered the process whereby we found out how rain falls from clouds.
OK, granted, this probably wasn't the most pressing thing for scientists to look into, but at some point Tor Bergeron would have looked up at the clouds and thought "Howcome all that moisture in the cloud turns into rain and falls from it?" Though he probably would have thought that in Swedish...
It's thanks to the Bergeron process which is used in all numerical models that charts which show the cloud cover :-
Can determine where will fall as rain :-
Here is a picture of Tor Bergeron taken in 1955 (he is the one standing up)
So, what did he come up with? Well, he discovered the fact of how super cooled water droplets attach themselves to ice crystals in clouds which then grow large enough to fall out of the clouds. Sounds simple right?
In fact, Tor came up with the idea of this being possible whilst walking through woods in 1922 and noticing how when temperatures were below freezing that the low cloud would remain above the tree tops and not descend to the land in cleared areas. However, when the temperature was above freezing then low cloud would come down to ground level.
The reason? Well, he said this was down to how the ice crystals on the tree leaves and branches would take vapour from the air and prevent it reaching the ground.
It was this process of how super cooled water attaches itself to ice crystals which allow them to grow large enough to fall which underpins the Bergeron process and covers how they grow too.
If that wasn't enough, then Tor also developed the science for understanding the occlusion process of fronts while working at the Bergen School of Meteorology when a cold front overtakes a warm front.
Granted, meteorologists had drawn occluded fronts on weather maps for years previously, but the actual process of how the cold front catches up with the warm front, the lifting mechanism and the triple point were never really fully understood.
Tor Bergeron died in 1977 aged 85 and had won the Symons Gold Medal in 1949 and the prestigious International Meteorological Organization Prize in 1966.
The legacy of the Bergeron process continues though, with many numerical weather models which use this in their Cloud Physics packages and every time you see a model run come through then a little bit of Tors work continues to this day.
So, all that is left to say is that Tor Bergeron, take a bow. Metcheck salutes you for all you have done for our fantastic science. |