““Snowball Earth” ended by methane – now an impossible theory“ (May 26, 2011). It seems that, like the White Queen in Through the Looking-Glass, Anthony Watts tries to believe six impossible things before breakfast. We see how hard he tries pretty much daily, but his apparent copy and paste delight here over a Caltech paper in Nature is just routine self-delusional over-interpretation.
“A hydrothermal origin for isotopically anomalous cap dolostone cements from south China” is about cap dolostone sediments overlying 600 million year-old glacial deposits and controversially thought to be associated with microbial consumption of abundant methane. The paper concludes that the cap dolostone was deposited after the abrupt end of a prolonged glacial period (aka Snowball Earth), not as it ended. Also, those rocks seem to have been formed under abiotic high-temperature hydrothermal conditions.
Thus, in Anthony’s fixated mind, it is impossible for greenhouse gases to cause abrupt ancient warming. Some other unspecified thing did.
Strangely the primary theory of how Snowball Earth ended doesn’t revolve around ocean sediment methane discharge, which this research seems to disprove. The primary theory is based on evidence of increased volcanic CO2 and methane emissions (greenhouse gases!) which this research can be inferred to support. Hydrothermal environments are associated with volcanism.
Note to Anthony: arguing over “abrupt” ancient natural climate change, taking place over millions of years, is a weak criticism of evidence for man-made climate change taking place thousands of times faster.