I know we all take for granted that, every morning and every evening, weathermen will pop up on the television and tell us what to expect in the weather for the next day, week, and sometimes even longer. We’re so used to it, in fact, that we roll our eyes and complain when they’re wrong – not realizing that we take for granted our ability to predict the weather at all.
Though the Franklin Institute in Philadelphia has been collecting and mapping weather data since 1831, for a long time it wasn’t really used for all that much. Weather prediction largely came from Farmer’s Almanacs, which were not exactly accurate. We had no real way to predict the weather until Norwegian father-son team Vilhelm and Jacob Bjerknes came on the scene in the late 1800s-early 1900s.
Geophysicists by trade, they decided to dedicate their lives and careers to further the collective understanding of how our atmosphere works.
Their work resulted in the weather models that we still use today.
In 1897 (incidentally, the same year his son Jacob was born), Vilhelm had a breakthrough when he landed on a theorem that accurately described the motion of a vortex in a non-homogenous fluid (such as the masses of air that interact in our atmosphere). He believed that, using this theorem, it would be possible to reliably predict weather patterns, and he said as much, laying out his future hopes in 1902:
“The goal is to predict the dynamic and physical condition of the atmosphere at a later time, if at an earlier given time, this condition is well known.”
Even though we now take for granted that weather patterns can be solved like physics problems, a hundred years ago his concept would have seemed pretty out there (and surely took some getting used to). Still, Vilhelm was determined, and his research began to pick up steam in 1913, when he was named the director of a new geophysics institute at the University of Leipzig in Germany.
It was there that he joined forces with a talented student, Vagn Walfrid Ekman, who had a theory about how the wind drives water currents. In 1915, Bjerknes’ son Jacob (Jack, to his friends) joined the project as well.
When WWI broke out in Europe, then ensnared the United States, Bjerknes worried that the upheaval in the world would hamper his work. What he couldn’t have predicted was the ways in which that war – and the one that came after – would become inextricably linked to his eventual successes.
In 1916, Jack took over the studies of doctoral student Herbert Petzold after the unfortunate man was killed at the Battle of Verdun. Soon after, he published his first paper describing the “convergence lines” of wind, and how they could be thousands of kilometers long, tended to drift eastward, and were connected – loosely – to clouds and precipitation.
A year later, the fighting in Germany sent the Bjerknes and their research fleeing to Norway. Vilhelm wrote, “I am now back in Norway, not merely for a summer journey, but forever,” after accepting a position as a professor at the Geofysisk Institute at the Bergen Museum – a place that would later be developed into his Bergen School, a major center for the study of weather analysis for years to come.
There were some perks to being back in Norway – for one, government grants helped Vilhelm increase the number of weather observation stations by nearly ten times, and he set Jack and two other students up as forecasters. The harsh winter of 1916-1917 (known as the Kohlrubenwinter, or “turnip winter”) also worked in their favor; in light of the scarcity, the government saw a clear value to being able to predict weather in order to ensure food production.
They were receiving a ton of data, which helped Jack Bjerknes prove his theory about lines and air masses: they were indeed connected with cyclones – large air masses that rotate around low atmospheric pressure.
In short, Jack had discovered the “front,” a term forever linked to the war around them.
As the war raged on, Jack and the others continued their work, eventually identifying the differing convergence patterns that made up “cold fronts” and “warm fronts.” Another member of the school, Tor Bergeron, proposed symbols for these fronts that were eventually adopted as the standard.
They were, slowly but surely, transforming the prediction of weather – meteorology – into a true science.
The 1920s, and the development of radio technology, allowed for the faster transmissions of information across the globe – including weather details. By 1922, the United States had 98 weather stations across 35 states, and they began exchanging daily observations with France that same year. By 1924, detailed daily pressure maps were being drawn of the entire Northern Hemisphere. Vilhelm retired in 1932, though he remained scientifically active until his death in 1951.
Then, another war.
Jack, who had spent a few years as the head of the Weather Forecasting Office for western Norway before returning to teach meteorology at the Bergen Museum, took his wife and children to the United States for a lecture tour in 1939 – a planned 8-month trip that became permanent when the Nazis invaded Norway.
Back at home, the Norwegian weather alert service was forced to halt not only its work, but its transmissions to the rest of the world, as well.
The United States recognized what they’d gained in Jack Bjerknes and immediately asked him to start a school for training weather officers in the Air Force. Accepting, he started the Department of Meteorology at the University of California’s Los Angeles campus, a department that remains at the forefront of the field today.
Jack wasn’t done contributing major conceptual leaps either – as collaborative efforts from around the world advanced weather forecasting by leaps and bounds, it was Jack Bjerknes who would guess that El Nino was not a phenomenon local to Peru at all, but the result of a global oceanic oscillation that had impacts all over the world. After Jack’s death in 1975, his biographer Arnt Eliassen wrote that “more than any other atmospheric scientist, Jack Bjerknes managed to create order and system in a seemingly disorderly atmosphere.”
And it’s true that while technology like satellites have modernized weather maps in ways we couldn’t have imagined even thirty or forty years ago, the theories developed and tested by both Vilhelm and Jack Bjerknes remain the constant behind them. Their Norwegian cyclone model is the solid ground from which all other meteorological advancements have leapt.
h/t: Atlas Obscura