User:Viriditas/Snowball Earth hypothesis

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"Snowball Earth" is a nickname for a period in Earth's geological past when the planet was thought to be covered with ice. The term is often used in quotes to indicate it is being used to refer to this period. "Snowball Earth hypothesis" (SEH) refers to the collection of evidence supporting the idea. SEH is the primary topic where the "Snowball Earth" period is discussed. The term "Snowball Earth hypothesis" is widely used, from popular books to specialist encyclopedias, from newspapers and magazines to journals and university press releases. To avoid amibiguity and to insure accuracy, Wikipedia uses full titles whenever possible. The use of the word "hypothesis" in article titles is a common and standard naming convention. Wikipedia articles should be based on reliable, published secondary sources and, to a lesser extent, on tertiary sources. This includes article titles, so long as they are compliant with Wikipedia policies. The secondary and tertiary literature favors the term "Snowball Earth hypothesis". The primary literature also uses the term when reporting new research or analysis. Wikipedia is a tertiary source and it would be instructive to see how other tertiary sources treat the subject. The best example can be found in an encyclopedia entry titled "Snowball Earth hypothesis", published on the Encyclopædia Britannica Online website:

in geology and climatology, an explanation first proposed by American geobiologist J.L. Kirschvink suggesting that Earth's oceans and land surfaces were covered by ice from the poles to the Equator during at least two extreme cooling events between 2.4 billion and 580 million years ago. The evidence for this hypothesis is found in old rocks that preserved signs of Earth's ancient magnetic field. Measurements of these rocks indicate that rocks known to be associated with the presence of ice were formed near the Equator. In addition, there is a 45-metre- (147.6-foot-) thick layer of manganese ore in the Kalahari Desert with an age corresponding to the end of the 2.4 billion-year “Snowball Earth” period; its deposition is thought to have been caused by rapid and massive changes in global climate as the worldwide covering of ice melted. Two important questions arise from this hypothesis. First, how, once frozen, could Earth thaw? Second, how could life survive periods of global freezing? One proposed solution to the first question involves the outgassing of massive amounts of carbon dioxide by volcanoes, which could have warmed the planetary surface rapidly by enhancing the planet's so-called greenhouse effect, especially given that major carbon dioxide sinks (rock weathering and photosynthesis) would have been dampened by a frozen Earth. One possible answer to the second question may lie in the existence of present-day life-forms within hot springs and deep-sea vents, which would have persisted long ago despite the frozen state of Earth's surface. Alternatively, meltwater ponds on the surface of the ice or warmer refugia near active volcanoes may have provided sanctuary to early life-forms. Much debate continues to surround this idea, and many critics have voiced their support for a competing premise called the "Slushball Earth hypothesis."

Another good tertiary source on the subject is the current entry for the "Snowball Earth Hypothesis" in the Encyclopedia of Paleoclimatology and Ancient Environments (2009), authored by Grant M. Young of the Department of Earth Sciences, University of Western Ontario:

The snowball Earth hypothesis (SEH) suggests that the Earth experienced surface temperatures so low that virutally its entire surface was covered by glaciers and/or thick sea ice periodically during its early history. Such a condition has been hypothesized for parts of the Neoproterozoic Era from about 750 million years ago (Ma) to about 500 Ma [...] A similar frozen state has been proposed during the early part of the Paleoproterozoic Era at about 2.300 Ma. There is little evidence of glaciation in the long intervening period but recently Williams (2005) presented evidence for glaciation in the Kimberly region of Western Australia at about 1.800 Ma.

When two major encyclopedia entries, authored by published experts in their respective fields, choose to use the term "Snowball Earth hypothesis" while Wikipedia does not, should an attempt be made to reconcile the difference? Is this a red flag? Could editorial bias or ignorance be at work here? For example, noting the above, I moved Snowball Earth to Snowball Earth hypothesis. My page move was reverted approximately ten minutes later by a user who had never edited the article before and disputed the move. Looking into this further, the user in question had only 20% of their edits in article space, while a whopping 32% in project space. All of this with a total of only 16,373 edits since 2003, with almost no activity between 2003-2005. The evidence points to this account being used primarily for administrative purposes only, not for editing. When asked why the page move was reverted, I was promptly informed that the user was an expert and they personally knew the page move was wrong. When it was pointed out that reliable sources clearly and explicitly prefer the term "Snowball Earth hypothesis" over the ambiguous "Snowball Earth" (which, depending on the context, can refer to the glacial period or the hypothesis) and that the person who coined the term uses "Snowball Earth Hypothesis", I was informed by the user that the use of the term in primary sources were more important. The user argued that "my personal experience as a geophysicist is that scientists in papers and presentations don't feel compelled to use the extended form and often do not." The problem is that this rationale contradicts WP:PSTS. Scientific papers and presentations are generally considered primary sources, and Wikipedia articles are named and composed based on secondary sources first, and specialist literature second. Even so, the "papers and presentations" don't need to use the term "hypothesis" but often do, even when the authors are communicating with their peers. Because the user in question has such a low percentage of their work in article space, I might assume that they are not familiar with the applicable policies and guidelines. In addition to the two reliable tertiary sources cited above, the table below shows that the secondary literature favors the term "Snowball Earth hypothesis" to describe the topic, often using "Snowball Earth" in quotes as a nickname for both the glacial period and also as shorthand for the hypothesis.

Other questions

• How many articles currently use the word "hypothesis" in their title?
• How many use redirects instead?

Table

Sample of published literature

Author	Credentials	Source	Title	Usage	Date	Notes
Archer, David		Science	Who Threw That Snowball?	Abstract: "The Sun grows hotter with time, yet the temperature at Earth's surface does not leave the narrow constraints of the melting and boiling points of water — at least not for long. The overall stability of Earth's climate is generally attributed to a balance between degassing of CO2 from deep within Earth, and consumption of CO2 by weathering reactions at Earth's surface. The Snowball Earth hypothesis is based on geological evidence of multiple glaciations at sea level in low latitudes. The leading explanation for the Snowball is a runaway ice-albedo feedback. When ice sheets reach some critical latitude, they reflect so much solar energy back into space that the entire planet freezes over. In the frozen world, weathering stops. Hydro-thermal iron becomes more abundant than weathering sulfur in the anoxic ocean, generating the first banded iron formations on Earth in 1000 million yearsVol." 302 Issue 5646, p791-792	2003-10-31	Journal; Archer's paper uses the term "Snowball Earth" to refer to the geological period in the correct context, and to the hypothesis when discussing evidence.
AScribe - The Public Interest Newswire		Europe Intelligence Wire	U.T. Dallas, Hebrew University Scientists to Test 'Snowball Earth' Hypothesis; Project in Ethiopia to Study 700MillionYearOld Climate Change.	"This project will test the Snowball Earth hypothesis, which explains perplexing features of 800 million- to 570-million-year-old sedimentary deposits that indicate the Earth's climate fluctuated dramatically between episodes when the planet was covered with ice and episodes when the climate was much hotter than it is today," said Stern.	2003-07-16	Newswire
Henderson, Mark		The Times	When the Earth was a snowball ...twice	Research from the University of Vienna has revealed the strongest evidence yet supporting the controversial "Snowball Earth" hypothesis, which holds that runaway global cooling has sheathed the planet in ice as many as four times.	2005-04-08	Newspaper
Olcott, Alison N.; Sessions, Alex L.; Corsetti, Frank A.; Kaufman, Alan J.; Oliviera, Tolentino Flavio de		Science	Biomarker Evidence for Photosynthesis During Neoproterozoic Glaciation.	Abstract: Laterally extensive black shales were deposited on the São Francisco craton in southeastern Brazil during low-latitude Neoproterozoic glaciation [approximately]740 to 700 million years ago. These rocks contain up to 3.0 weight % organic carbon, which we interpret as representing the preserved record of abundant marine primary productivity from glacial times. Extractable biomarkers reflect a complex and productive microbial ecosystem, including both phototrophic bacteria and eukaryotes, living in a stratified ocean with thin or absent sea ice, oxic surface waters, and euxinic conditions within the photic zone. Such an environment provides important constraints for parts of the "Snowball Earth" hypothesis. v. 310, no. 5747, p. 471-474.	2005-10-21	Journal
Simpson, Sarah		Scientific American	Triggering a Snowball	Abstract: Reports that Harvard University researchers have proposed a theory that methane addiction caused the ice age to occur. Snowball earth hypothesis which was proposed by the same group to explain severe climate reversals; Description of the proposed scenario, which involves an interrupted leakage of methane gas into the atmosphere of a frozen Earth; Skepticism about the theory after it was presented in Edinburgh, Scotland. 09285:3, 20(2)	2001	Popular science
Staff		Biotech Week	Geology and GSA Today media highlights	GEOLOGY includes three papers about Mars; continuation of the "jelly sandwich" versus "creme brulee" debate; support for the Snowball Earth hypothesis; what nine-million-year-old tooth enamel says about vegetation in an ancient sub-Himalayan ecosystem; anthropogenic lead in the Tyrrhenian Sea; evidence for a prehistoric South Pacific tsunami; a multicentennial megadrought in medieval Europe; and a newly discovered fossil turtle in the Canadian Arctic. GSA Today's science article proposes a new method for classifying Quaternary glacial deposits (see also Geological Society of America)...Macdonald et al. report stratigraphic studies on a newly discovered Neoproterozoic glacial deposit and bounding carbonate rocks in western Mongolia. The juxtaposition of cold-water glacial deposits and warm-water carbonate rocks is consistent with the Snowball Earth hypothesis. Integration of this stratum into the Neoproterozoic record of climate change also places constraints on the timing of basin formation and early accretion in Central Asia.	2009-03-04	Press release
Staff		Yakima Herald-Republic	YVCC lecture features noted geologist	Paul Hoffman, who has spent years studying and promoting the "Snowball Earth" theory, is coming to Yakima on April 18 at the invitation of the Yakima Geology Club... His lecture, part of the 2008-09 High Demand Visiting Lecture Series at Yakima Valley Community College, is free and open to the public. It will be followed by a reception to give attendees a chance to meet with the award-winning Harvard University geology professor and researcher. In addition to the "Snowball Earth" hypothesis, Hoffman's specialties include pre-Cambrian plate tectonics, the succession of supercontinents and the evolution of North America. He will talk about "Snowball Earth: Ancient Climate Disasters that Sparked the Rise of Complex Animal Life."	2009-10-04	Newspaper
Staff		New Scientist	How Snowball Earth melted into a mudball.	Abstract: "The article discusses a study which involved the use of climate models to examine how dust from volcanoes and the weathering of rocks would affect the thawing of Earth if it was entirely frozen over millions of years ago, in relation to the Snowball Earth hypothesis. According to researchers Dorian Abbot and Raymond Pierrehumbert of the University of Chicago in Illinois, they discovered that in regions with minimal snowfall, enough dust would have accumulated to change the surface sufficiently so that the Earth absorbed sunlight and thawed." Vol. 204 Issue 2736, p19-19	2009-11-28	Popular science
Suplee, Curt		The Washington Post	Big Chill Theory Starts to Snowball	By any standard, it was the mother of all cold snaps. About 700 million years ago, give or take an epoch, the Earth's surface froze solid. Every inch of land was covered with glaciers. The ocean was trapped under half a mile of ice. Life -- which in those days consisted of little more than single- and multicelled goop -- shuddered on the cusp of extinction. In the past two years, the "snowball Earth" hypothesis has gained even more support. And although it is still furiously debated and by no means confirmed, the idea is now a staple of mainstream geoscience." p. A9	2000-05-29	Newspaper