Climate Science: Frequently Asked Questions from the IPCC

Please note that this material is from the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), Working Group 1, published in 2007. The latest climate science can be found in the IPCC’s 6th Assessment Report, published in August 2021. For other reports and further updates, please refer to the IPCC website.

If you are not a climate scientist or meteorologist yourself but you need to engage them and/or the data visualisations (graphs & maps) and the information they produce and make available in scientific papers, assessment reports and web portals, then it may be useful to familiarise yourself with some basics of the science of climate change.

Working Group 1 of the Intergovernmental Panel on Climate Change (IPCC), a large group of the top scientists internationally doing research on the climate system, put together a set of frequently asked questions (FAQs) that provide a very useful starting point. Here is a list of the questions they address and a link to a short version of the answers they provide. 

• What Factors Determine Earth’s Climate? 
• What is the Relationship between Climate Change and Weather? 
• What is the Greenhouse Effect?  
• How do Human Activities Contribute to Climate Change and How do They Compare with Natural Influences?
• How are Temperatures on Earth Changing?
• How is Precipitation Changing?
• Has there been a Change in Extreme Events like Heat Waves, Droughts, Floods and Hurricanes? 
• Is the Amount of Snow and Ice on the Earth Decreasing?
• Is Sea Level Rising?
• What Caused the Ice Ages and Other Important Climate Changes Before the Industrial Era?
• Is the Current Climate Change Unusual Compared to Earlier Changes in Earth’s History? 
• Are the Increases in Atmospheric Carbon Dioxide and Other Greenhouse Gases During the Industrial Era Caused by Human Activities?  
• How Reliable Are the Models Used to Make Projections of Future Climate Change?
• Can Individual Extreme Events be Explained by Greenhouse Warming? 
• Can the Warming of the 20th Century be Explained by Natural Variability?
• Are Extreme Events, Like Heat Waves, Droughts or Floods, Expected to Change as the Earth’s Climate Changes?
• How Likely are Major or Abrupt Climate Changes, such as Loss of Ice Sheets or Changes in Global Ocean Circulation?
• If Emissions of Greenhouse Gases are Reduced, How Quickly do Their Concentrations in the Atmosphere Decrease?
• Do Projected Changes in Climate Vary from Region to Region? 

Reference

IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment, Report of the Intergovernment Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.