Publication Abstracts

Fahey et al. 2017

Fahey, D.W., S.J. Doherty, K.A. Hibbard, A. Romanou, and Taylor P.C., 2017: Physical drivers of climate change. In Climate Science Special Report: Fourth National Climate Assessment, Volume I. D.J. Wuebbles, D.W. Fahey, K.A. Hibbard, D.J. Dokken, B.C. Stewart, and T.K. Maycock, Eds., U.S. Global Change Research Program, pp. 73-113, doi:10.7930/J0513WCR.

Human activities continue to significantly affect Earth's climate by altering factors that change its radiative balance. These factors, known as radiative forcings, include changes in greenhouse gases, small airborne particles (aerosols), and the reflectivity of the Earth's surface. In the industrial era, human activities have been, and are increasingly, the dominant cause of climate warming. The increase in radiative forcing due to these activities has far exceeded the relatively small net increase due to natural factors, which include changes in energy from the sun and the cooling effect of volcanic eruptions. (Very high confidence)

Aerosols caused by human activity play a profound and complex role in the climate system through radiative effects in the atmosphere and on snow and ice surfaces and through effects on cloud formation and properties. The combined forcing of aerosol-radiation and aerosol-cloud interactions is negative (cooling) over the industrial era (high confidence), offsetting a substantial part of greenhouse gas forcing, which is currently the predominant human contribution. The magnitude of this offset, globally averaged, has declined in recent decades, despite increasing trends in aerosol emissions or abundances in some regions (medium to high confidence).

The interconnected Earth-atmosphere-ocean system includes a number of positive and negative feedback processes that can either strengthen (positive feedback) or weaken (negative feedback) the system's responses to human and natural influences. These feedbacks operate on a range of time scales from very short (essentially instantaneous) to very long (centuries). Global warming by net radiative forcing over the industrial era includes a substantial amplification from these feedbacks (approximately a factor of three) (high confidence). While there are large uncertainties associated with some of these feedbacks, the net feedback effect over the industrial era has been positive (amplifying warming) and will continue to be positive in coming decades (very high confidence).

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BibTeX Citation

  author={Fahey, D. W. and Doherty, S. J. and Hibbard, K. A. and Romanou, A. and Taylor P. C.},
  editor={Wuebbles, D. J. and Fahey, D. W. and Hibbard, K. A. and Dokken, D. J. and Stewart, B. C. and Maycock, T. K.},
  title={Physical drivers of climate change},
  booktitle={Climate Science Special Report: Fourth National Climate Assessment, Volume I},
  publisher={U.S. Global Change Research Program},
  address={Washington, D.C.},

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RIS Citation

ID  - fa01100l
AU  - Fahey, D. W.
AU  - Doherty, S. J.
AU  - Hibbard, K. A.
AU  - Romanou, A.
AU  - Taylor P. C.
ED  - Wuebbles, D. J.
ED  - Fahey, D. W.
ED  - Hibbard, K. A.
ED  - Dokken, D. J.
ED  - Stewart, B. C.
ED  - Maycock, T. K.
PY  - 2017
TI  - Physical drivers of climate change
BT  - Climate Science Special Report: Fourth National Climate Assessment, Volume I
SP  - 73
EP  - 113
DO  - 10.7930/J0513WCR
PB  - U.S. Global Change Research Program
CY  - Washington, D.C.
ER  -

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