Milutin Milanković
Early Life and Education
Milutin Milanković was born on May 28, 1879, in the village of Dalj, located in the Austro-Hungarian Empire, which is now part of Croatia. He was the eldest of seven children in a Serbian family. His early education was conducted at home under the guidance of private tutors, which was common for families of his social standing. Milanković demonstrated an early aptitude for mathematics and physics, subjects that would later become central to his scientific career.
In 1896, Milanković enrolled at the Vienna University of Technology, where he studied civil engineering. He graduated in 1902 with a degree in engineering and continued his studies, earning a doctorate in technical sciences in 1904. His doctoral thesis focused on the theory of elasticity, a branch of mechanics that studies the deformation of solid objects under various forces.
Academic Career
After completing his doctorate, Milanković worked as a civil engineer in Vienna, where he was involved in the design and construction of various structures, including bridges and dams. However, his passion for theoretical research led him to accept a position as a professor of applied mathematics at the University of Belgrade in 1909. This move marked the beginning of his long and distinguished academic career.
At the University of Belgrade, Milanković's research interests expanded to include astronomy, geophysics, and climatology. He became particularly interested in the mathematical theory of climate and its long-term changes, a field that would later bear his name.
Milankovitch Cycles
Milanković is best known for his theory of Milankovitch cycles, which describes the collective effects of changes in the Earth's movements on its climate over thousands of years. These cycles are driven by variations in three key parameters: eccentricity, axial tilt, and precession.
Eccentricity
Eccentricity refers to the shape of the Earth's orbit around the Sun. The orbit varies from nearly circular to more elliptical over a cycle of approximately 100,000 years. These changes affect the distance between the Earth and the Sun, thereby influencing the amount of solar radiation the Earth receives.
Axial Tilt
Axial tilt, or obliquity, is the angle between the Earth's rotational axis and its orbital plane. This tilt varies between about 22.1 degrees and 24.5 degrees over a cycle of approximately 41,000 years. Changes in axial tilt affect the distribution of solar radiation between the equator and the poles, influencing the severity of seasons.
Precession
Precession refers to the wobble in the Earth's rotational axis, which completes a cycle approximately every 26,000 years. This wobble affects the timing of the seasons relative to the Earth's position in its orbit, thereby altering the distribution of solar radiation.
Contributions to Climatology
Milanković's work on the mathematical theory of climate laid the foundation for our understanding of ice ages and long-term climate change. He proposed that variations in the Earth's orbit and axial tilt could explain the timing of glacial and interglacial periods. His theory was initially met with skepticism but gained acceptance over time as more evidence emerged to support it.
Milanković's calculations showed that changes in solar radiation due to orbital variations could lead to significant changes in the Earth's climate. He published his findings in a series of papers and books, including his seminal work, "Kanon der Erdbestrahlung und seine Anwendung auf das Eiszeitenproblem" (Canon of Insolation and the Ice-Age Problem), published in 1941.
Legacy and Recognition
Milanković's contributions to science extend beyond his work on climate cycles. He made significant advances in the fields of astronomy and geophysics, including the development of a new method for calculating the secular perturbations of planetary orbits. His work has had a lasting impact on our understanding of the Earth's climate system and the factors that drive long-term climate change.
In recognition of his contributions, several honors and awards have been bestowed upon Milanković. These include the naming of a crater on the Moon and another on Mars in his honor. The Milankovitch Medal, awarded by the European Geosciences Union, is named after him and recognizes outstanding research in long-term climate change.
Personal Life
Milanković married Kristina Topuzović in 1914, and the couple had two children. Despite the demands of his academic career, Milanković was a devoted family man and maintained a close relationship with his wife and children. He was also an avid reader and enjoyed literature and philosophy.
Milanković passed away on December 12, 1958, in Belgrade, leaving behind a rich legacy of scientific achievement. His work continues to influence the fields of climatology, astronomy, and geophysics, and his theories remain a cornerstone of our understanding of the Earth's climate system.