Part 5: Climate Change - Isn't It Natural?

More urban myths about climate change are busted as Peter looks at the Earth's climate over the last 500 million years. What causes it to change? Since carbon dioxide was much higher in the past, why do climatologists say higher CO2 now poses a problem? And of course there's the familiar myth that CO2 can't influence temperatures because the climate was much colder in the past when carbon dioxide levels were much higher.
REFERENCES:
"CO2-forced climate thresholds during the Phanerozoic" -- D.L. Royer, Geochimica et Cosmochimica Acta, Dec 2006
"Celestial driver of Phanerozoic climate?" -- N. Shaviv and J. Veizer, GSA Today, 2003
"Bathymetric and isotopic evidence for a short-lived late Ordovician glaciation in a greenhouse period" -- Brenchley et al, Geology; April 1994
"Reconciling Late Ordovician (440 Ma) glaciation with very
high (14X) CO2 levels" -- CROWLEY T. J. ; BAUM S. K., Journal of Geophysical Research 1995
"An atmospheric pCO2 threshold for glaciation in the Late Ordovician"
-- M. T. Gibbs et. al, Geology; May 1997
"A weathering hypothesis for glaciation at high atmospheric
pCO2 during the Late Ordovician." -- L.R. Kump et al, Palaeoclimatology alaeogeography
Palaeoecology 1999
"Long-lived glaciation in the Late Ordovician? Isotopic and se-
quence-stratigraphic evidence from western Laurentia" -- M. R. Saltzman,S. A. Young, Geology; February 2005
Graph at 2:28 showing increasing solar output taken from James Imamura at the University of Oregon Dept of Physics, jersey.uoregon.....
"Solar Activity Over the Last 1150 Years: Does it Correlate with Climate?" -- I. Usoskin et.al, Proceedings of The 13th Cool Stars Workshop, 2004
If you have a problem with any of the research that has been done into climate change, please do not waste your time discussing it on UA-cam. Write a paper and have it published in a respected, peer-reviewed journal. And no use complaining to us or Peter if you think you have found flaws in the work of a particular researcher, write to them and let them know. They will be absolutely delighted to hear from you.
This video series is made by the former science correspondent Peter Hadfield who has a genuine interest in reporting the facts, not the media hype. Peter runs the very popular UA-cam channel potholer54 and it is for this channel he originally made this series.
The Flagship Movement is always working towards informing the general public about anything related to sustainability and as climate change in recent years have become a central part of any sustainability work, and the debate about it have become so infected with unscientific nonsense - we felt that we needed to try and clear things up a bit using the actual science. We felt that Peter's UA-cam series are among, if not THE best regarding the issue of climate change.