Talk:Greenhouse and icehouse Earth

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Tropical climate at poles
If the poles reach tropical temperatures, what temperatures do the tropics reach? Twilight Realm (talk) 21:57, 3 December 2008 (UTC)
 * They get warmer, but not so much warmer as do the poles - the temperature increases are greater at higher temperatures. —Preceding unsigned comment added by 90.227.95.62 (talk) 18:37, 15 July 2009 (UTC)
 * I think you meant to write that temperature increases are more pronounced at higher latitudes  — Preceding unsigned comment added by 174.49.84.214 (talk) 14:24, 31 August 2011 (UTC)

This should be deleted - the terms Greenhouse Earth and Icehouse Earth are politically loaded terms; not encyclopedic
I'm all for making sound science accessible to the masses, but when world governments are making decisions based on suspected human influence on climate change, I think it's critical to keep the science which influences those decisions as rigorous as possible and to keep corresponding articles in Wikipedia as accurate and well cited as possible. Making portals or categories with trendy, invented, or otherwise non-scientific terms erodes my trust in the quality of the scientific content of such articles, which is why I recommend sticking with the traditional, accepted scientific terms: Interglacial (Webster's Ninth New Collegiate Dictionary say this was coined in 1867) and Glacial (1656), even if both such terms sound "cold" in at a time when the earth is getting warmer. --GlenPeterson (talk) 16:55, 15 July 2010 (UTC)

You haven't grasped the distinction between "glacial" and interglacial" on the one hand and "icehouse earth" and "greenhouse earth" on the other. "Icehouse earth" describes a very long-term state of the Earth in which glacials and interglacials can occur; "greenhouse earth" describes the opposite condition in which there is no or very little ice at the poles (as in say the Eocene when palm trees and turtles flourished in the Arctic) and there are no glacials or interglacials. The present icehouse earth began tens of millions of years ago and has absolutely nothing to do with human activity. —Preceding unsigned comment added by 82.32.72.129 (talk) 15:32, 24 December 2010 (UTC)

Agree with GlenPeterson, these terms of iceball earth and slushball earth and greenhouse earth are comments generally found in Discovery Channel documentaries meant to sensationalize a topic to draw viewers. There is already a wonderful language of science that documents the earth's climatic history and do not need to create dubious pseudo and unscientific (and potentially politically charged) categories for these topics.174.49.84.214 (talk) 14:32, 31 August 2011 (UTC)

These terms are used in stadard undergraduate academic books like Ruddiman "Earth's climate past and future" and several other similar places. The definitions of these terms are simple and concrete (presence or absence of continental ice), and are not related to the issue of anthropogenic climate change in the last 100 years or so. They are clearly not the same as interglacial and glacial periods. Bj norge (talk) 11:41, 3 January 2012 (UTC)

It appears to me that the terms "icehouse Earth" and "greenhouse Earth" are used in serious research papers, cf the Journal of the Geological Society article "Oceanic gateways as a critical factor to initiate icehouse Earth" []. While the article here is not sophisticated and could use some attention, it's a reasonable subject to include in an encyclopedia. (OEJ)

Sounds like someone hates the idea that the Earth being hot and lacking surface ice is by far its most natural state and that we're in the ending of the Little Ice Age. All I'm hearing sounds like "That Earth normally doesn't have any ice and life thrives in that condition goes against my political beliefs so it should be censored."

Over the geological history of the Earth the planet's climate has been fluctuating between two dominant states: the Greenhouse and the Icehouse?
The basic premise of this article appears dubious to me. Or, possibly uninteresting by definition. Since the article defines greenhouse as "no ice" and icehouse as "some ice" then the lede statement is equivalent to "there is not always ice, and there is not always no ice" William M. Connolley (talk) 09:12, 11 March 2013 (UTC)


 * No one? OK, I've redirected this to Ice age, lets see who squeals William M. Connolley (talk) 18:54, 17 March 2013 (UTC)


 * Good heavens, "let's see who squeals?!?" There's no consensus for deleting this entire 5-1/2 year old article, with its 26 scholarly references!  NCdave (talk) 14:29, 23 March 2013 (UTC)

Yeah, there's really no justification to just delete the entire article. The concept is clearly within scientific literature and not just a mad idea. Certainly the article needs some improvement, I tried to do that somewhat last year and cleaned up a lot of bad grammar and poorly worded sentences, but there is still plenty of things that might need changing. The subject of this article really is quite different from that of the Ice Age article, which deal mostly with the last Ice Age, this is all about how climate changed over hundreds of millions of years. There's no equivalent article (that I know of) that talks about the long and intense greenhouse periods for instance, there's bits and pieces of that information around Wiki, like the various geological period articles, but this tries to put into a bigger context. --Hibernian (talk) 15:49, 23 March 2013 (UTC)


 * Merege, most with Climate change NewsAndEventsGuy (talk) 20:30, 23 March 2013 (UTC)


 * It doesn't really fit with the Climate change article, which is mostly about much shorter time-scales, anthropogenic change, etc. This is quite different. NCdave (talk) 22:17, 23 March 2013 (UTC)

This page should be kept intact, not merged and certainly not deleted. It discusses a notable subject and is well-sourced. It could use improvement, but there's no reason to get rid of it. –Prototime (talk · contribs) 20:48, 23 March 2013 (UTC)
 * Do you agree there is substantial overlap with Climate change ?  NewsAndEventsGuy (talk) 21:16, 23 March 2013 (UTC)
 * Not anymore overlap than there is between climate change and articles on global warming, global cooling, global dimming, ice ages, and so forth. Also, see NCdave's comment above. –Prototime (talk · contribs) 22:34, 23 March 2013 (UTC)
 * But despite good faith NCdave mis-characterizes Climate change; Those shorter time scale (s)he mentions (like human global warming) is the subject of Global warming and discussion of general mechanisms of climate change - just in general - is the subject of Climate change.  There has been an unshaken consensus to do it that way ever since I started editing a couple years ago.  This article would be easy to merge, in my opinion, with about a paragraph of text in our treatment of the general-mechanisms, the top article for which is Climate change. NewsAndEventsGuy (talk) 23:00, 23 March 2013 (UTC)


 * The Climate change article is mostly focused around modern climate change with a few asides about the ancient past. Besides, that article is already bloated with many sub-articles needed to cover the topics involved, I don't see why this article can't be one of those sub-articles, it just needs to be integrated better with the other articles and cleaned up a bit. --Hibernian (talk) 01:13, 24 March 2013 (UTC)

This article has no real content that wasn't in ice age. That's why I redirected it. The subject of this article really is quite different from that of the Ice Age article, which deal mostly with the last Ice Age - no, its doesn't. Have you read it? William M. Connolley (talk) 21:50, 24 March 2013 (UTC)
 * We could implement the content into climate state. Prokaryotes (talk) 13:27, 9 April 2014 (UTC)

Difference Between "Icehouse Earth", "Ice Age", and "Glacial Period"
Upon some reflection, I believe the course of action that would be most fair to the content and purpose of this page, while addressing William M. Connelley's concerns, would be to create a new, separate article for "greenhouse earth" (with substantially more content than this current article says about the subject), retain "icehouse earth" as a redirect to "ice age", and merge the current contents of this article as appropriate into the articles for "greenhouse earth", "ice age", and "snowball earth". William M. Connolley is correct in noting the substantial overlap between the content on this page and ice age; the icehouse sections of this article--which covers much of the material discussed on the ice age article and the snowball earth article--have much more material compared to the greenhouse sections, which have hardly a few sentences. (I actually find it astonishing that there is both a section of this page and a separate, comprehensive article devoted to the subject of Snowball Earth, which is an uncertainty in earth's climate history, while the subject of Greenhouse Earth--the predominate climate state of the earth during the planet's history--has barely a few sentences between this article and the ice age article!) Thoughts? –Prototime (talk · contribs) 03:03, 25 March 2013 (UTC)
 * Either way, I did make some edits to this article in an attempt to clean it up a bit. –Prototime (talk · contribs) 03:32, 25 March 2013 (UTC)
 * There is a distinction between an "ice age", a period of glaciation, and "icehouse world", a much longer (scores of millions of years) period when ice ages are common. Can you have an article about Greenhouse Earth without discussing its opposite and counterpart? Martin  (Smith609 – Talk)  10:11, 25 March 2013 (UTC)
 * I'm not sure that there is such a distinction; ice ages last millions of years, with glacial periods occurring over thousands of years. I haven't seen any definition of "icehouse earth" that distinguishes it from an "ice age" (although I do know of many instances where people erroneously equate "ice age" with "glacial period.") I admit that I am not an expert though; do you know of any scientifically-recognized difference between the terms "icehouse earth" and "ice age"? –Prototime
 * @ William M. Connolley, maybe I should have been more careful in my wording, what I meant was that the Ice Age article deals with explaining the Ice Ages, but for the most part doesn't talk about the hot Greenhouse periods (it lists all the ice ages and talks about how they happened, but it seems to ignore the ice-free periods in-between). There are differences in the terminology between the articles, such as this article making a clear distinction between an "Ice Age" and an "Ice House", and the Ice Age article making no such distinction (the word Ice House is not even mentioned there). There are other contradictions, like the Ice Age article says "By this definition, we are still in the ice age that began 2.6 million years ago at the start of the Pleistocene epoch, because the Greenland and Antarctic ice sheets still exist", but this article says we have been in the current Ice House period since the Antarctic ice sheets began to form 34 million years ago (unless "we" refers only to the Northern Hemisphere). So which is it? As I would see it there are two issues concerning what articles Wiki should have on this: Firstly, is there a clear distinction between the meaning of "Ice Age" and "Ice House"? If so then we need separate articles, if not then Ice House can be a redirect to Ice Age and that article should explain how the terms are used. Secondly, if this article is merged or whatever, we would probably need to create a new article about the Greenhouse periods of the Earth, because that aspect still needs a focus. --Hibernian (talk) 12:59, 25 March 2013 (UTC)
 * I agree with the points you bring up here. It especially seems critical to determine the difference between the definitions of "icehouse earth" and "ice age", if there is any difference. –Prototime (talk · contribs) 16:39, 25 March 2013 (UTC)

Because these questions do not seem to have a clear answer, or at least an answer that those of us participating in this conversation is aware of, I have placed an expert banner in the article in hopes of finding assistance. –Prototime (talk · contribs) 17:38, 5 April 2013 (UTC)

Percentage of glacial periods during "icehouse earth" phase
In the section "Glacials and interglacials", the following information is presented: "During an Icehouse, only 20% of the time is spent in interglacial, or warmer times," citing Broecker/Denton as reference. The last sentence of the last section "Modern conditions" reads: "Permanent ice is actually a rare phenomenon in the history of the Earth, occurring only during the 20% of the time that the planet is under an icehouse effect," without referencing any source. These sentences directly contradict each other: If only 20% of the icehouse period is spent in interglacial conditions, the remaining 80% are spent in glacial conditions, i.e. with permanent ice somewhere on Earth. Since the first sentence names a credible source, while the second does not name a source, I propose deletion of the second sentence. It is simply wrong.


 * That's a misunderstanding, as the sentences talk about different things. The first sentence talks about an ice age or icehouse period, which is a long period with glaciation, and it says that interglacial, warm periods within an icehouse period make up only 20% of the time of that period. However, the second sentence talks about the whole of Earth's history, and says that icehouse periods only make up 20% of the whole history of Earth. The last ice age or icehouse period is still ongoing, while we are currently in an interglacial period within that ice age. We are not in a greenhouse period, only in a relatively warmer period within a long cold period in the history of Earth, an ice age (although we might end up creating an artificial, man-made greenhouse period inadvertently). Clearer now? --Florian Blaschke (talk) 02:18, 8 January 2016 (UTC)

Plimer article
I tagged the Plimer article ("The Past is the Key to the Present") as unreliable. The article disagrees strongly with the scholarly consensus on global climate change, and is not published in a peer-reviewed journal. IPA Review is the publication of a pro-free market think tank/lobbying organization, and so this article does not meet the standards of wp:rs. Hopefully someone can find a replacement for it, and rework the article accordingly. Dowiha (talk) 00:42, 21 January 2014 (UTC)
 * The link cites now with "Greenhouse to icehouse" http://www.esta-uk.net/index_htm_files/TES%20Issue%2035%201.pdf#page=33 Prokaryotes (talk) 17:51, 9 April 2014 (UTC)

reference: CO2 "350 times modern levels", is this right?
Article says: "From such models, scientists have determined that the atmospheric carbon dioxide of the Earth could have been up at least 350 times higher than our modern day levels.[5]" I haven't read the referenced article, but is it quoted correctly? Is it a concensus statement? Also "modern levels" is ambiguous. 250ppm recently or 400ppm now? Can someone get a more exact statement from the reference? 350 x 250ppm = 8.75%. Could that be true? Wouldn't that seem to disprove the possibility of a runaway-positive-fredback-to-Venus-condition, since no one says CO2 will go that far and runaway didn't happen when that maximum was reached earlier?GangofOne (talk) 23:38, 16 November 2015 (UTC)
 * Carbon dioxide in Earth's atmosphere says " Reconstructions show that concentrations of CO2 in the atmosphere have varied, ranging from as high as 7,000 ppm during the Cambrian period ..." . (needs ref). That contradicts this artice which says 350 x 400ppm == 140000 ppm. What gives? GangofOne (talk) 05:22, 2 May 2017 (UTC)
 * The claim seems implausible. The reference used is acceptable, but not of super high quality, so I suspect its just a typo in the ref, or some failure of calculation William M. Connolley (talk) 11:40, 2 May 2017 (UTC)
 * also, it gets added as "researched for a class". That probably means the whole thing needs attention William M. Connolley (talk) 11:41, 2 May 2017 (UTC)

Next glacial period naturally 50,000 years from now?
"Without the human influence on the greenhouse gas concentration, the Earth would be heading toward a glacial period. Predicted changes in orbital forcing suggest that in absence of human-made global warming the next glacial period would begin at least 50,000 years from now[18] (see Milankovitch cycles)."

AFAIK the Holocene optimum was reached ~6,000 years ago and temperatures have been on average falling since (not accounting for man-made global warming), so it seems to me unlikely that we're indeed at the beginning of a huge interglacial. In fact I've heard this number in other context: a newspaper article a couple years ago claimed that we've postponed the next glacial for 50,000 years. E.g. here 93.136.99.236 (talk) 21:48, 12 March 2018 (UTC)


 * Generally speaking, you shouldn't believe what you read in the newspapers about climate change (or indeed anything) without independent corroboration. But in this case the article appears accurate, you've just misread it. It says "Man-made carbon emissions mean the world is unlikely to see another ice age for 100,000 years - 50,000 years later than without human influence". Which is to say, the natural period would be 50k yr, and GW adds more. The thing you're probably thinking of is "interglacials last 10 kyr", but that's just wrong William M. Connolley (talk) 22:01, 12 March 2018 (UTC)


 * Indeed it does say that. I had memorized the title but apparently not the content. Thanks for clearing this up. FWIW I knew about the Holocene optimum so w/o further information I expected the temperature vs time graph to be most likely symmetrical with a descent back to the cold in the next 5-10,000 years. Of course there is no logical reason for that to be true. 93.136.99.236 (talk) 00:21, 13 March 2018 (UTC)


 * One big problem with this article is the use of the term "Greenhouse" Earth" instead of the alternative term "Hothouse Earth", which produces many hits with Google Scholar. The former term implies that GHGs or the GHE are the cause of warming periods, but there is a section called "Causes of Greenhouse Earth" that mentions other causes.  In reality, a GHE is always operating and GHGs were always present, though in differing amounts.
 * The second big problem is that the article doesn't explain what characteristics clearly differentiate a Greenhouse/Hothouse Earth from an Icehouse Earth.
 * The third big problem is misuse of the term "cause". The openings of the Tasmanian gateway and the Drake Passage may or may not be CORRELATED with the beginning of a Cenozoic icehouse, but the CAUSE is (always) that the temperature at which incoming and outgoing radiation were in equilibrium dropped.  If these geological changes reduced heat transport to polar regions, permitting more extensive ice and snow cover and increasing the planet's albedo, one might be speculating about a chain of causation that could be supported by citations.  IIRC, today Antarctica is supposed to be somewhat cut off from the warmer rest of the planet (and therefore colder) by ocean currents that circle the continentFhobbs (talk) 16:28, 28 September 2018 (UTC)

It's incorrect anyway. We just left the Little Ice Age. We're easy fifty thousand years from the next Ice Age even if humans did not exist. And the idea humans are expanding the time to twice it's norm is insanely ridiculous. It MUST be assuming continued human expansion and release of greenhouse gases throughout the normal fifty thousand year time. Because by modern amounts it's just not possible.

Misc criticism
"virtually no chance of being induced by anthropogenic activities." Riiight. Unless we hit 400ppm CO2 and spark the temperature ⇌ water vapor, runaway global warming effect with exponential relative humidity levels. Was this article written 60 years ago?! 2001:1970:529E:EC00:A465:95F0:3F71:D63A (talk) 00:40, 6 December 2018 (UTC)

Oxygen levels with the release of gasses from oceans
Scientists have noticed that the Earth's temperature rises before the greenhouse gases amount does and so attributes the vast majority of the gases to the evaporation of surface water such as in oceans. I just watched some Jurassic Park/World videos and it suddenly hit me that during the hot Earth periods of time animals tend to be insanely massive and life thrives dramatically specifically because there was far more oxygen in the air in those times. So, does the increased evaporation also increase the oxygen content? This would also explain the exceptionally frequent and hot wild fires the world has been having. If so, then does that mean we can expect animals and plants to increase significant in size and physical abilities to utilize the increased oxygen content of our atmosphere? Perhaps by the time we meet aliens we'll be ten foot tall supermen and Earth will be like Catachan.

Paywalled ref
The first sentence used a paywalled ref... for something so basic please add a readily available one. The deleted reference is NewsAndEventsGuy (talk) 19:45, 17 February 2019 (UTC)

Proposed merge from CLIMATE STATE into GREENHOUSE AND ICEHOUSE EARTH
Climate state covers the same topic as this article, and this article is more developed.NewsAndEventsGuy (talk) 21:50, 17 February 2019 (UTC)
 * Agree. I think the title Greenhouse and Icehouse earth is more clear as well. Femkemilene (talk) 14:40, 8 March 2019 (UTC)
 * Disagree. Climate state is a terminology used in many instances/studies, and not always applied when discussing states, nor always related to geological epochs, ie. NOAA's annual State of the Climate. I rather would merge this article into CS, since it constitutes the umbrella terminology. prokaryotes (talk) 23:30, 5 June 2019 (UTC)
 * Disagree. This article, Greenhouse and icehouse Earth, is about a specific process on Earth, whereas Climate state is about a variety of conditions that might exist on terrestrial planets. There is quite a bit more material that could be included in both articles, especially as more discoveries are made in the very active areas of solar system exploration and exoplanetology. They should not be merged at all.  Sparkie82  ( t • c ) 03:40, 10 September 2019 (UTC)
 * Note: This merger idea was previously discussed here.  Sparkie82 ( t • c ) 03:40, 10 September 2019 (UTC)
 * Housekeeping note: the merger was carried out in September as per the proposal. EMsmile (talk) 21:09, 20 September 2023 (UTC)

Strange section in Greenhouse Earth (Causes)
There is a block of text that appears to have been lifted wholesale from another source, complete with numbered references that do not match the numbering used in this article. The section is from "Volcanoes emit massive amounts..." until "...into the atmosphere.(37)" The parts of the article before and after this seem to flow into one another, so it looks like someone just pasted a block of text into the middle of the paragraph without regard for placement or formatting. The section could simply be moved so as not to interrupt the flow of the surrounding text, but the fact that these other reference numbers were left in makes me think it was just copied and pasted from another source, which should perhaps be investigated by someone with more expertise than myself. Lumberjane Lilly (talk) 19:32, 3 August 2022 (UTC)

Wrong webpage for Late Paleozoic glaciation link
I think the intended webpage for the link was "Late Paleozoic icehouse", instead it goes to the webpage "Paleozoic". Zalbicolis (talk) 16:28, 23 January 2023 (UTC)