Search results
Results from the WOW.Com Content Network
The key conclusions of Working Group I [11] were: . An increasing body of observations gives a collective picture of a warming world and other changes in the climate system (The global average surface temperature has increased over the 20th century by about 0.6 °C; Temperatures have risen during the past four decades in the lowest 8 kilometres of the atmosphere; Snow cover and ice extent have ...
The Geological Society of America (GSA) concurs with assessments by the National Academies of Science (2005), the National Research Council (2006), and the Intergovernmental Panel on Climate Change (IPCC, 2007) that global climate has warmed and that human activities (mainly greenhouse‐gas emissions) account for most of the warming since the ...
Furthermore, climate change may disrupt the ecology among interacting species, via changes on behaviour and phenology, or via climate niche mismatch. [9] The disruption of species-species associations is a potential consequence of climate-driven movements of each individual species in opposite directions.
The NRC committee's report (the North report) was published on 22 June 2006. [5] Committee member John Michael Wallace said that "Our conclusion is that this recent period of warming is likely the warmest in the last millennium", and added that "This doesn't change the scientific landscape in terms of the greenhouse warming debate". [12]
In 2004, the geologist and historian of science Naomi Oreskes analyzed the abstracts of 928 scientific papers on "global climate change" published between 1993 and 2003. 75% had either explicitly expressed support for the scientific consensus on anthropogenic climate change, or had accepted it as a given and were focused on evaluating its ...
This is complemented by Climate Field Reconstruction (CFR) methods which show how climate patterns have developed over large spatial areas. Considerable care must be taken in the averaging process; for example, if a certain region has a large number of tree ring records, a simple average of all the data would strongly over-weight that region ...
The size of this warming is broadly consistent with predictions of climate models, but it is also of the same magnitude as natural climate variability. Thus the observed increase could be largely due to this natural variability; alternatively this variability and other human factors could have offset a still larger human-induced greenhouse warming.
Working Group I, dealing with the scientific aspects of climate, stated that carbon dioxide remains the most important contributor to anthropogenic forcing of climate change; projections of future global mean temperature change and sea level rise confirm the potential for human activities to alter the Earth's climate to an extent unprecedented in human history; and the long time-scales ...