1923 - 2010

Hot towers, tropical meteorology

Who has not spent hours laying on the grass looking at the clouds? Maybe this is how Joanne Simpson started admiring them, for later on becoming an extraordinary meteorologist. Indeed, before Joanne Simpson, clouds were deemed unimportant in meteorology. But thanks to her, now we know that clouds are key players of the atmosphere.

Most commonly known for her discoveries in the field of tropical atmosphere, and her famous work on hot towers, Joanne Simpson’s life is an example of perseverance, curiosity, and talent.

Born in 1923 in Boston, US, Joanne was already flying with his father on a two-passenger high-wing monoplane at the age of six. This was the first of many flights throughout her life. At 17 years old, as a college student, Joanne was already piloting small aircrafts as a civilian pilot, while studying meteorology, air navigation, and the physics of aircrafts and their engines. Soon after that, she gained her commercial pilot license.

During her bachelor, World War II started, and volunteers were needed. The opportunity was there. Encouraged by C. G. Rossby, a worldwide renowned atmospheric scientist, she joined the Army Air Corps. Doing so, she could continue her studies and learn more about aviation and meteorology.

After the war, women were expected to abandon their career interest and become house-wives. But that was not Joanne’s plan. Against all odds, and being pregnant, she gained her master of science. After that, she pursued a PhD with Rossby as main supervisor, despite his opinion on the topic being: “No woman has ever earned a PhD in meteorology. No woman ever will. Even if you did, no one would give you a job.”

Joanne started investigating tropical cumulous clouds. At the time, clouds research was not given much importance. Rossby even mentioned that this was a good job “for a little girl”, hindering that clouds had no important role on the weather. But despite discouragements, she embarked on the field of tropical meteorology, alongside Herbert Riehl as PhD advisor. She profiled atmospheric parameters, took samples, and designed mathematical models. And in 1949 she accomplished her PhD.

She worked at the Woods Hole Oceanographic Institute in Massachusetts, where she was given a navy aircraft. At the time, little was known from the important role of the tropics in the Earths global atmosphere, field in which Joanne’s job was key.

In 1958, working with Riehl, Joanne proposed the ‘hot tower’ hypothesis, which described that the big thunder clouds in the tropics power hurricanes and trade wins, influencing the Earths global atmospheric circulation. This tropical convection became key in the understanding of global climate.

After Woods Hole, Joanne taught in California and Virginia, became advisor to the US Weather Bureau’s National Hurricane Research Project, and joined the Experimental Meteorology Laboratory. She also led the NASA Tropical Rainfall Measuring Mission (TRMM), a satellite program to study hurricanes, rain fall...

Joanne faced burdens in her career, but she ‘flew over them’ and succeeded. As a curiosity, she published under three married names, which makes difficult to follow her career.

She received many awards, including the Carl-Gustaf Rossby Research Medal, highest award in atmospheric science. Additionally, the American Meteorological Society (AMS) has a research award on her name, The Joanne Simpson Tropical Meteorology Research Award, which “is granted to researchers who make outstanding contributions to advancing the understanding of the physics and dynamics of the tropical atmosphere.”

Written by: Enriqueta Vallejo-Yagüe.