The International Earth Science Olympiad (IESO), one of the thirteen International Science Olympiads, is an annual competition for secondary school students that tests their abilities in disciplines such as geology, meteorology, environmental science, and terrestrial astronomy. Students who are winners of the respective national competitions are invited to participate in the IESO, and all interested countries are encouraged to contribute to the IESO.
It is one of the major activities of the International Geoscience Education Organization - IGEO that aims at raising student interest in and public awareness of Earth sciences, as well as to enhance Earth science learning of students.
The IESO was first suggested by Korean earth scientists. In 2003, the Korean Earth Science Society (KESS) organized the first Korean Earth Science Olympiad. The international competition was adopted as one of major activities of International Geoscience Education Organization later that year.
In November 2004 in Seoul, representatives from ten countries gathered to discuss the curriculum and the format of IESO. 23 presentations were made and the IESO Advisory Committee was established with members including Chairperson Moo Young Song, Hendra Amijaya, Roberto Greco, Ken-ichiro Hisada, Thomas Lorillard Tailer, Chang Chun-Yen, Miguel Cano, Shankar Rajasekharaiah, and Chan-Jong Kim. The IESO Syllabus Commission was then developed in 2005, and the first International competition was held in 2007.
The first IESO was held in October 2007 in Daegu, South Korea, where the Chinese Taipei team won first place with three gold medals and one silver medal. The Korean team placed second with one gold and three silver medals, the United States followed in third with two silver and two bronze medals, and India was placed fourth with two silver medals.
Second (2008) competition took place in Manila, Philippines, with the theme "Cooptition in Addressing Climate Change" (the word "cooptition" refers to a combination of competition and cooperation). Its aim was to promote global Earth science education and international cooperation in mitigating anthropogenic harm to the environment.