TWOMEY, SEAN ANDREW Dr. Sean Andrew Twomey of Tucson, Arizona and San Diego, California has passed away following a brief illness in Tucson. Born in Cork, Ireland in 1927, Dr. Twomey graduated from University College Cork in 1948 with a Master of Science degree and was awarded a Doctorate degree in Physics by the National University of Ireland in 1955. He accepted a position with CSIRO in Australia, where his research and papers rapidly established his reputation as one of the world's preeminent atmospheric physicists. During his move to Australia, he met the love of his life, Marie McInerney, on the deck of an ocean liner making its way across the Indian Ocean. In the late 1950s, Dr. Twomey joined a team of researchers and physicists developing a payload for the Naval Research Laboratory's Vanguard project. Shortly thereafter he was hired as a research scientist at NRL, and he relocated his family to Oxen Hill, Md. While there, he played a crucial role in the development of weather satellites launched by NASA and other research institutions around the world. In 1962, a tragic car accident claimed the life of Dr. Twomey's son, Patrick, and resulted in his hospitalization for over a month as he battled life-threatening injuries. In 1967, Dr. Twomey returned to CSIRO, and the family relocated to Sydney, Australia. In 1974 Dr. Twomey published a paper (Pollution and the Planetary Albedo) that significantly changed the understanding of the impact of pollution on the climate and was a precursor to the scientific community's concern for global climate change. In 1976, Dr. Twomey accepted a research professorship at the University of Arizona in Tucson, where he moved with his family. Dr. Twomey's passions were physics, mathematics, and horse racing. He enjoyed tennis, sailing, horseback riding, public transportation, and classical music. He was preceded in death by his father Tadhg O'Tuama and his mother Lil(Walsh), his wife of 56 years, Marie, and his son Patrick. He is survived by his brother Fergus (Dublin, Ireland), sister Ide (Dublin, Ireland), daughter Adele (Geelong, Australia) , sons Timothy (Cobb, CA), Kieran (San Diego, CA) and Damian (Tucson, AZ), and grandchildren Kenneth (Long Beach, CA), Bridgid (Santa Barbara, CA), Linda (Geelong, Australia), and Sofia (Cobb, CA). A memorial service will be on Wednesday the 21st of November at 3 p.m., in the winner's circle at Del Mar Race Track. low.