Kevin E Trenberth; 7 November 2016
This is an Amicus Curiae Declaration in support of
The Commission on Human Rights of the Philippines
of Kevin E. Trenberth, Sc.D.:
1. My name is Kevin Trenberth. I reside in Boulder, Colorado. I am over 21 years of age and have
personal knowledge of the statements contained herein. In this declaration, I provide information about
the impacts of human-induced climate change on changing climate extremes. I am a distinguished senior
scientist in the Climate Analysis Section at NCAR, the National Center for Atmospheric Research. The
expert opinions I provide herein are my own and do not necessarily reflect the views of the National
Center for Atmospheric Research or the National Science Foundation.
2. I have authored over 540 publications in the area of climate, and given hundreds of talks on the
subject. I am among the most highly cited researchers in all of geophysics. I have extensively
investigated global-scale climate dynamics, the observations, processes and modeling of climate
changes from interannual to centennial time scales. I have particular expertise in El Niño, the
hydrological and energy cycles, hurricanes and storms, and climate change. I have served on many
national and international committees including National Research Council/National Academy of Science
committees, panels and/or boards. I co-chaired the international Climate Variability and Predictability
(CLIVAR) Scientific Steering Group of the World Climate Research Programme (WCRP) from 1996 to 1999
and I have served as a member and officer of the Joint Scientific Committee that oversees the WCRP as a
whole from 1998 to 2006. I chaired the WCRP Observations and Assimilation Panel from 2004 to 2010
and from 2010 to 2014 I chaired the Scientific Steering Group of GEWEX: the Global Energy and Water
Cycle Experiment of WCRP. I remain involved in CLIVAR committees. I have been involved in global
warming science and extensively involved in the Intergovernmental Panel on Climate Change (IPCC)
scientific assessment activity as a lead author of individual chapters, the Technical Summary, and
Summary for Policy Makers (SPM) of Working Group (WG) I for the Second, Third and Fourth
Assessment Reports (SAR, TAR and AR4; IPCC 1996, 2001, 2007). I was a Coordinating Lead Author for
the SAR and AR4, and in the latter I led Chapter 3 that dealt with observations of the surface and
atmospheric climate change. I was a Review Editor of the Fifth IPCC Assessment Report (AR5) in 2013.
3. The IPCC is a body of scientists from around the world convened by the United Nations jointly under
the United Nations Environment Programme (UNEP) and the World Meteorological
Organization (WMO) and initiated in 1988. Its mandate is to provide policy makers with an objective
assessment of the scientific and technical information available about climate change, its environmental
and socio-economic impacts, and possible response options. The IPCC reports on the science of global
climate and the effects of human activities on climate in particular. Major assessments were made in
1990, 1995, 2001, 2007, and 2013. Each new IPCC report reviews all the published literature over the
previous 5 to 7 years, and assesses the state of knowledge, while trying to reconcile disparate claims and
resolve discrepancies, and document uncertainties. The IPCC process is very open. The strength is that it
is a consensus report. For the Policy Maker’s Summary, scientists determine what can be said, but the
governments help determine how it can best be said. Negotiations occur over wording to ensure
accuracy, balance, clarity of message, and relevance to understanding and policy. The latest reports
reaffirm in much stronger language that the climate is changing in ways that cannot be accounted for by
natural variability and that “global warming” is happening.
4. I am very concerned about the damage already occurring from climate change, not the least of which
has affected the Philippines, especially through stronger and bigger typhoons. It happens that some of
my research touches on this issue.
Kevin E Trenberth