If you don’t find the term that you are looking for here, please leave a comment so that I can update the list.
Anthropogenic: Originating in human activity.
El Niño: An upwelling of warm water over large parts of the Pacific Ocean which effects temperatures in the atmosphere. This can lead to dramatic warming over a large parts of the earths surface. Some authorities claim that new scientific capabilities will allow these oscillations to be predicted, others state that the causes are still not sufficiently well understood. La Niña is a similar phenomenon that has the opposite effect, causing cooling of the climate. Both these events are part of the natural variability of the earth’s climate and occur periodically at irregular intervals.
Intergovernmental Panel on Climate Change: this very influential body was set up in 1988 by two United Nations agencies: UNEP (United Nations Environment Program) and WMO (World Meteorological Organisation). The IPCC undertakes no research itself, but makes assessments of the scientific evidence for anthropogenic global warming based on research published in peer reviewed journals. It publishes an assessment report roughly every six years. The two most recent reports (2001 and 2007) have had enormous influence on both public policy and public opinion. Although the IPCC process is usually represented as being objective, authoritative and transparent, there is also deep and well informed concern that this organisation is in fact partisan, secretive and highly politicised. This uncertainty about the IPCC’s objectivity makes it difficult to form judgements about the validity of its pronouncements. It is probably fair to say that the assessment reports make the strongest possible case for anthropogenic global warming that scientific evidence can support.
IPCC: see Intergovernmental Panel on Climate Change
La Niña: see El Niño.
Palaeoclimatology: the study and reconstruction of past climates, particularly those preceding instrumental records. Until the early 1990s, historical, archaeological, geological, zoological, botanic and other similar evidence was used for this purpose. More recently, data obtained from tree rings, ice cores, lake and ocean sediments, and even the shells of marine creatures have been used. These types of proxy data (see below) can only be interpreted as evidence of past global climate by means of complex statistical analysis and considerable concern has been expressed about some of the methods that are used. The ‘Hockey Stick Graph’, which formed the centrepiece of the 2001 IPCC report, is an example of this kind of reconstruction.
Peer Review: the process by which research papers that are submitted to academic journals are scrutinised by independent specialists before being accepted for publication. The intention is to prevent bad science being published and has served the scientific community well for centuries, but recently there has been increasing concern about its effectiveness. As scientific research becomes increasingly specialised, it is difficult for editors to find reviewers who are at the same time sufficiently removed from the field of research to be objective and also qualified to form an opinion. This can lead to sound research that challenges orthodox opinion being rejected at the review stage while less robust findings that confirm the opinions of the majority are published.
Proxy data: data that can be used to yield other data which may not be obtainable by other means. For example, the width and density of the annular tree rings provide evidence of growing conditions, particularly temperature and precipitation, in corresponding years where instrumental data are not available.
Sceptic: This word has many definitions, but here it is used in the sense of one who questions orthodox views rather than simply accepting them. Elsewhere it is used as a term of abuse by militant advocates of anthropogenic climate change.
Summary for Policy Makers: because the IPCC’s assessment reports are of great length and complexity - typically over a thousand pages of highly specialised scientific argument - brief summaries of the findings are produced for those without the expertise or time to study the complete documents. Politicians, administrators and the media rely on these to determine what conclusions the IPCC has reached. In the past there have been suggestions that these documents may not adequately reflected the degree of uncertainty that is expressed in the main reports and that they are drafted in a way that maximises their impact.
Warmist: Anyone who accepts or promotes the idea that humans are causing climate change. On this blog it has no defamatory connotations. It simply saves typing terms like ‘ proponent of anthropogenic climate change’ over and over again.