Glossary of Climate Change - P

P

• Pacific decadal oscillation (PDO) - a 23-year pattern of warm or cool water in the north Pacific.
• Paleocene–Eocene Thermal Maximum (PETM) - a sudden warming event that fundamentally altered geological and biological aspects of the planet.
• Paleoclimatology - the study of climate change taken on the scale of the entire history of Earth.
• Polar amplification - greater temperature increases in the Arctic than in the earth as a whole) is a result of the collective effect of feedbacks and other processes." It does not apply to the Antarctic, because the Southern Ocean acts as a heat sink.
• Polar city - a proposed human refuge located in northern regions of the Earth, and in Tasmania, New Zealand and the Antarctica, where people might have to live in order to survive major global warming "events" in the far distant future, also dubbed Lovelock Retreats.
• Proxy - a variable that can be related to one of interest (e.g. tree rings can be proxies for temperature variations).