The paper provides a geologically long - term perspective on recent temperature changes in the Northern Hemisphere and the ability of climate models, such as the National Oceanic Atmospheric Administration and National Center for Atmospheric Research (NCAR) models used in the study, to predict the changes,» says Shuman, senior author on the paper and Marsicek's supervisor. (sciencedaily.com)
If the behaviour of recent temperature change is to be understood, and the mechanisms and causes correctly attributed, parallel efforts are needed to reconstruct the longer and more widespread pre-instrumental history of climate variability, as well as the detailed changes in various factors that might influence climate (Bradley et al., 2003b; Jones and Mann, 2004). (ipcc.ch)
We can not, therefore, ascribe observed recent temperature changes to any one particular cause. (realclimate.org)