Warren Knapp, professor emeritus of meteorology and climate in the Department of Earth and Atmospheric Sciences, and the second director of Cornell’s Northeast Regional Climate Center, died Oct. 3 in Ithaca. He was 82.

Knapp brought engineering skill to the study of weather and climate, finding sophisticated and precise ways to measure and record day-to-day and annual fluctuations in temperature, radiation, precipitation and pollution. He gathered hard data to document global warning. From the late 1970s to the late 1980s, he managed Cornell’s acid rain monitoring program, part of the National Atmospheric Deposition Program, as he documented acid rain in Adirondacks and the brown cloud hovering over Denver.

Knapp came to Cornell in January 1969 as an assistant professor of atmospheric sciences in the College of Agriculture and Life Sciences’ Department of Agronomy.

Throughout his career at Cornell, he taught students the core mathematical principles of atmospheric thermodynamics, hydrostatics and dynamics. His popular Atmospheric Physics class taught students the physics behind such atmospheric phenomena as rainbows, haloes and mirages.

In 1988, Knapp became the second director of the Northeast Regional Climate Center (NRCC) at Cornell. He modernized the university’s Game Farm Road weather station from manual to electronic observations, and oversaw the climate center’s growth and operation until his retirement in 2001.

Under his directorship, the NRCC transitioned its accessible climate information from paper data sheets to internet availability. His scientific papers focused on applications of climate information in agriculture and long-term statistics of precipitation and snowfall.

Radio and television meteorologists relied upon data obtained from the Northeast Regional Climate Center.

Atmospheric science graduate students, postdoctoral researchers, faculty colleagues and family all looked forward to his annual winter solstice party. On the longest, darkest night of the year, he brought cheer with his quiet, charming demeanor. Continuing a tradition from his graduate school days, he assembled a group to toast the sun with a warm cup of Swedish glugg.

This winter solstice ritual never failed to bring the sun back to the Northern Hemisphere, his colleagues said.

Warren Willard Knapp was born in Fort Dodge, Iowa, in 1938, and grew up in Decorah, Iowa, and LaCrosse, Wisconsin. His parents were Willard B. Knapp and Shirlee Mather Knapp, and he graduated from LaCrosse Central High School in 1956. He began his college studies in electrical engineering at LaCrosse State College and transferred to the University of Wisconsin-Madison, where he changed his major to meteorology and met Jeanette Dudley, his wife of 59 years.

Subsequently, Knapp earned his bachelor’s (1960), master’s (1963) and doctoral degree (1969) all at the University of Wisconsin-Madison.

Knapp  is survived by his wife, Jeanette, and their three daughters, Laura Knapp of Washington, D.C.; Sara Nicolls of Naples, Florida, and Solebury, Pennsylvania; and Cecily Spencer and her husband Nathan of Gloucester, Massachusetts, and their children, Calvin, Hope and Jason Spencer.