High above the Earth’s surface — between 50km and 1,000km — is the ionosphere. The ionosphere is a very thick layer of charged particles, where free electrons exist in a number sufficient to influence the transmission of electromagnetic waves at radio frequency. When these ions move in the Earth’s magnetic field, a dynamo effect means that current is induced, which in turn produces changes in the magnetic field on Earth’s surface that affect the planet in a host of ways. Professor Francisca Okeke’s research has resulted in new discoveries about the part of the ionosphere located above the equator.
Helping to Understand Climate Change
Francisca Okeke, the first woman ever to head the physics department of the University of Nigeria in Nsukka, has dedicated much of her career to studying the ionosphere and the “equatorial electrojet phenomenon.” Energized by the sun, the electrojet is a river of electrical current that traverses the globe eastward around the dip equator and causes the magnetic field at the dip equator to vary almost five time more than anywhere else on the planet. (The dip or magnetic equator differs from the equator by a few degrees, as the Earth’s magnetic north pole is different from what we generally think of as the north pole.)
Professor Okeke’s research on how such solar activity in the ionosphere affects the Earth’s magnetic field could lead to a better understanding of climate change and help pinpoint sources of dramatic phenomena like tsunamis and earthquakes.
Childhood curiosity is at the root of Francisca Okeke’s remarkable achievements and her passion for studying the heavens began long before she became a physicist. “As a little girl I was fascinated by the sky, why it was sometimes white and sometimes blue, why airplanes could fly instead of falling back to the Earth. Later, once I was in school, I found my vocation when I learned that the answers to these questions could be found in physics.” Continuing the tradition of childhood curiosity, Fransica Okeke has six children, all of which are embracing scientific careers.
Of Men and Mentors
When asked about entering, and subsequently thriving in a field which remains dominated by men, Professor Okeke indicates that her own personal experience has been better than that of most women. “My late father, a mathematician and educator, was a great mentor and he began teaching me higher mathematics at a young age. When I graduated in 1980 there were thirty undergrads in physics and only two of us were women. Fortunately, my astrophysicist husband also gave me lots of inspiration and encouragement, too.”
Others of her generation did not fare as well. “At the time, society approved of women who possessed what were thought of as typically female characteristics—among others, passivity, emotionality, intuition and receptiveness.”
Professor Francisca Okeke won the 2013 Loreal-UNESCO awards for Africa and Arab states. Little wonder, then, that she considers this award, “a challenge that encourages me to work harder, particularly in providing the leadership to young women scientists. I need to encourage them to forge ahead.”