Human influences on the Climate System — ASN Events

Human influences on the Climate System (10363)

Nathan Bindoff 1
  1. IMAS, University of Tasmania, CSIRO Marine and atmospheric, Sandy Bay, TAS, Australia

IPCC Fifth Assessment Report on the physical science of climate change was released on the 27th of September 2013. In that report the evidence for human influence on the climate system is presented. Human influence has been detected in the major assessed components of the climate system. The combined evidence increases the level of confidence in the attribution of observed climate change, and reduces the uncertainties associated with assessment based on a single climate variable.

From this combined evidence it is virtually certain that human influence has warmed the global climate system and that for some variables the human influence is extremely likely more than half the observed changes. Human influence has been identified in changes in temperature near the surface of the earth, in the atmosphere and in the oceans, as well as changes in the cryosphere, the water cycle and some extremes.

The alternative explanation for the observed changes for the period since 1950 was also assessed. It was concluded that there is strong evidence that excludes solar forcing, volcanoes, and internal variability as the strongest drivers of warming since 1950. This talk will also address some of the remaining gaps in our understanding of the human influence in the climate system.