Stephen McIntyre (born c. 1947) is a Canadian mining exploration company director, a former minerals prospector and semi-retired mining consultant whose work has included statistical analysis. He is the founder and editor of Climate Audit, a blog which analyses and discusses climate data. He is a critic of the temperature record of the past 1000 years and the data quality of NASA's Goddard Institute for Space Studies. He has made statistical critiques, with economist Ross McKitrick, of the hockey stick graph which shows that the increase in late 20th century global temperatures is unprecedented in the past 1,000 years.

McIntyre, a native of Ontario, attended the University of Toronto Schools, a college-preparatory school in Toronto, finishing first in the national high school mathematics competition of 1965. He went on to study mathematics at the University of Toronto and graduated with a Bachelor of Science degree in 1969. McIntyre then obtained a Commonwealth Scholarship to read philosophy, politics and economics (PPE) at Corpus Christi College, Oxford, graduating in 1971. Although he was offered a graduate scholarship, McIntyre decided not to pursue studies in mathematical economics at the Massachusetts Institute of Technology.

McIntyre started work for Noranda and worked for 30 years in the mineral business, the last part of these in the hard-rock mineral exploration as an officer or director of several public mineral exploration companies. He was the president and founder of Northwest Exploration Company Limited and a director of its parent company, Northwest Explorations Inc. When Northwest Explorations Inc. was taken over in 1998 by CGX Resources Inc. to form the oil and gas exploration company CGX Energy Inc., McIntyre ceased being a director. McIntyre was a strategic advisor for CGX in 2000 through 2003. McIntyre says that during his career his skills in statistical analysis enabled him to analyse mineral prospecting data and out-bet his rivals. He also occasionally worked as a government policy analyst, including a period at the federal Anti-Inflation Board.

Prior to 2003 he was an officer or director of several small public mineral exploration companies. He retired from full-time work, but still sometimes engaged in mining consultancy. He is an active squash player and once won a gold medal in the World Masters Games in squash doubles.

In April 2011, Trelawney Mining and Exploration Inc. of Toronto, Ontario announced the appointment of McIntyre to their board of directors and then later to chairman in June 2011. In September 2011, McIntyre was appointed to the board of directors of Augen Gold Corp., which was shortly acquired by Trelawney Mining and Exploration Inc. in November 2011. In October 2011, McIntyre was appointed to the board of directors of Southeast Asia Mining Corp. and later resigned in May 2012. Trelawney Mining and Exploration Inc. was acquired by Iamgold Corporation in June 2012.

In 2002, McIntyre became interested in climate science after a leaflet from the Canadian government warning of the dangers of global warming was delivered to his residence. McIntyre states that he noticed discrepancies in climate science papers that reminded him of the false prospectus that had duped investors involved in the Bre-X gold mining scandal.

The Canadian government pamphlets were based on the IPCC Third Assessment Report section, which prominently displayed the hockey stick graph based on the 1999 reconstruction by Mann, Bradley and Hughes (MBH99). McIntyre began studying Mann's research, which had produced the graph, and met Ross McKitrick. McIntyre has remarked on how his suspicions of this graph were aroused: "In financial circles, we talk about a hockey stick curve when some investor presents you with a nice, steep curve in the hope of palming something off on you."

McIntyre & McKittrick's papers were cited by Senator Jim Inhofe and Representative Joe Barton to support their political criticisms of the MBH studies, and Representative Sherwood Boehlert requested the National Academy of Sciences in the United States to arrange an investigation. The outcome was the North Report, published in 2006, which endorsed the MBH studies with a few reservations. The principal component analysis method criticised by McIntyre & McKittrick had a small tendency to bias results so was not recommended, but it had little influence on the final reconstructions, and other methods produced similar results.^{[non-primary source needed]}