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Do ice core records showing that warming preceded CO2 rise cast doubt on greenhouse warming?

By John Cook
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NO

Antarctic ice core records dating back 800,000 years suggest that increases in carbon dioxide lagged behind increases in temperature by a couple of hundred years. This observation has been used by some to incorrectly claim that modern CO2 emissions cannot be causing a rise in temperature. This misconception is based on the false dichotomy that warming is either driven by CO2 or CO2 is driven by warming. In reality, both are true.

In the past, warming was driven by variations in Earth’s orbit and tilt, resulting in changes in solar energy reaching Earth which caused some initial warming. This triggered the release of CO2 from oceans which caused additional warming. Thus, while CO2 first increased due to warming, the extra CO2 also caused additional warming.

Recent anthropogenic global warming cannot be explained by natural cycles, which are in their cooling phase.

See a full discussion of this at Skeptical Science
This fact brief is responsive to conversations such as this one.
Sources
Science Synchronous Change of Atmospheric CO2 and Antarctic Temperature During the Last Deglacial Warming
NASA Milankovitch (Orbital) Cycles and Their Role in Earth's Climate
American Institute of Physics The Carbon Dioxide Greenhouse Effect
NASA Why Milankovitch (Orbital) Cycles Can't Explain Earth's Current Warming
NASA Carbon Dioxide
ABOUT THE CONTRIBUTOR
Skeptical Science
Skeptical Science is a non-profit science education organization. Our goal is to remove a roadblock to climate action by building public resilience against climate misinformation. We achieve this by publishing debunking of climate myths as well as providing resources for educators, communicators, scientists, and the general public. Skeptical Science was founded and is led by John Cook, a Senior Research Fellow with the Melbourne Centre for Behaviour Change at the University of Melbourne.
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Fact briefs are short, credibly sourced summaries that offer “yes/no” answers in response to claims found online. They rely on publicly available, often primary source data and documents. Fact briefs are created by contributors to Gigafact —a nonprofit project looking to expand participation in fact-checking and protect the democratic process. See all fact briefs here.