Mauna Loa is a featured article; it (or a previous version of it) has been identified as one of the best articles produced by the Wikipedia community. Even so, if you can update or improve it, please do so.
	This article appeared on Wikipedia's Main Page as Today's featured article on August 5, 2007.
Article milestones Date Process Result October 13, 2005 Good article nominee Listed October 23, 2005 Good article reassessment Delisted October 27, 2005 Good article nominee Listed April 8, 2006 Featured topic candidate Not promoted June 17, 2006 Peer review Reviewed July 11, 2006 Featured article candidate Promoted February 13, 2012 Peer review Reviewed Current status: Featured article

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The small section on climate is totally meaningless as is and should be either expanded or removed. It looks like some global warming scaremonger has inserted that piece of meaningless information so he could point to it as some sort of 'evidence' of global warming. It is in no way informative in its current state. — Preceding unsigned comment added by 122.106.157.135 (talk) 20:23, 3 June 2012 (UTC)[reply]

What on earth are you talking about? It's the average monthly temperatures from 1961-90, which incidentally is before warming really started to kick in. And it's informative for showing how cold it gets there at high elevations. KarlM (talk) 10:25, 4 June 2012 (UTC)[reply]

I think I see what the anon editor is talking about. Check out the graph here: [1] The high temperature of 85 degrees in February may be a problem with the data, not a real.temperature. I don't have a way to confirm or invalidate. —hike395 (talk) 09:26, 5 June 2012 (UTC)[reply]

Sounds like you've never been there - normally the wind keeps it cool, but the intense sun gets the lava extremely hot, and if there's no wind (as often happens in the winter) it can heat up the air during the day. Also note that this only occurred twice, the other extreme temps were 60-70. The anon is also a warming denialist, check out their next edit. KarlM (talk) 20:30, 9 June 2012 (UTC)[reply]

I'm in the process of revitalizing this article. It's an old FA from 2006 that would get demoted in a flash today. There's definitely value in it, but it needs better organization, better language, more information (lots of it), and finally, a trip through the meat grinder, er, FAR. My plan of action for now is to bring it around to FAR when it's good and ready, but until then, comments would be appreciated! ResMar 04:30, 16 December 2012 (UTC)[reply]

It was also inexplicably the most vandalized article I have on my watchlist, until it was semi-protected a while ago, so that may have degraded it. Chunks that were good may have been taken out and never replaced when people weren't paying attention. I've never seen an article about a non-controversial topic get as much vandalism as this one. KarlM (talk) 05:18, 16 December 2012 (UTC)[reply]

The Blue and Humpback whales regularly copped alot of vandalism - and yes, was frustrating to find missing paragraphs and have to go and fetch them. This is the value of FAC as a quasi-stable version (at the time of gaining FA status) to check against. Casliber (talk · contribs) 08:41, 16 December 2012 (UTC)[reply]

Mmm? Didn't notice this before. Yeah, I guess. At this point I'm through to eruptive history, leaving, oh let's see, Hazards (what's there is a nice base), Monitoring (slightly less so), Ascents (to be significantly cut back, what is all of this cruft on this or that expedition?), and new sections on Ecosystem and Recreation. And it's already standing at ~70 references. In for the long haul on this one. ResMar 04:15, 25 January 2013 (UTC)[reply]

One thing not explained (so far as I can see) in the article is the estimate on the age at 700k to 1million years when you oldest rock is only 200k years old. Not disputing the age, just looking to see how that was calculated, presumably based on average rate of deposition and total volume of unexposed rock. EdwardLane (talk) 11:57, 28 January 2013 (UTC)[reply]

It's an estimate based on the volcano's known stratigraphy and Hawaiian growth patterns. ResMar 19:07, 3 February 2013 (UTC)[reply]

Why doesn't the article give the height above sea level? I propose in the first paragraph "although its peak, at 4170m above sea level, is about 120 feet (37 m) lower than that of its neighbor, Mauna Kea."

Article seems to be locks so I can't edit it. 155.198.206.91 (talk) 10:15, 1 February 2013 (UTC)[reply]

The elevation is prominently placed in the infobox. I'll add the elevation to the lead once I get around to improving the lead, which is typically the last task. ResMar 19:08, 3 February 2013 (UTC)[reply]

I corrected the grossly wrong statement that was in there (before it said Mauna Loa depressed the sea floor by 5 miles, which is deeper than the entire ocean around it) to something that's approximately right by eyeballing ocean depths, but it would be helpful if someone could come up with a citation. I know this is a well known phenomenon but I can't find any myself. KarlM (talk) 00:16, 2 February 2013 (UTC)[reply]

To quote:

ResMar 19:00, 3 February 2013 (UTC)[reply]

Holy cow, what a poorly written and misleading paragraph. It's depressing (no pun intended) that that's on the SOEST web site. Note that these two close-by sentences contradict each other:

My point is, the ordinary depth of the ocean floor (if there is no mountain sitting on top of it) is about 15,000 ft. Around Mauna Loa, it's about 16,500, which means ML is depressing the seafloor by 1500 ft. A reference is needed for specific depths though. How they came up with that nonsensical second sentence, I don't know; you can't depress the seafloor by 26,000 ft when it's only 15,000 ft deep to begin with! KarlM (talk) 04:28, 4 February 2013 (UTC)[reply]

You're underestimating two things: a) the pure, massive, lateral bulk of solid core rock that is Mauna Loa; and b) that it's not necessarily the entire volcano that subsides the level described in these writings, but only its most central pillar. Here are some more sources:

I do not believe this many independent specialists could make this error. Your logic seems to be that it's somehow impossible, but you're a specialist on Hawaiian flora, not geology. Until I see actual empirical evidence otherwise, I'm reverting. ResMar 02:07, 5 February 2013 (UTC)[reply]

I think the article currently compares apples to oranges when comparing Mauna Loa to Everest. For the height of Mauna Loa, it uses the height from the root of the mountain somewhere in the lithosphere to the peak, while Everest is mean sea level to the peak. This doesn't seem right. Either the mountains should be compared to their non-rock bases (sea floor vs. base camp?) or both from their root (the asthenosphere level? that could be 250km down). A quick search did not reveal to me a reliable source for the depth of the asthenosphere below Mount Everest. —hike395 (talk) 14:06, 5 February 2013 (UTC)[reply]

Hmm, what to compare to what, then? ResMar 19:02, 5 February 2013 (UTC)[reply]

I don't know (yet). I'm trying not to perform original research. Height above sea level and topographic prominence are well-established criteria for comparing mountains. Looking for other ones supported by reliable sources. —hike395 (talk) 04:01, 6 February 2013 (UTC)[reply]

Can we qualify Everest's height as subaerial and leave it there for now? ResMar 05:08, 6 February 2013 (UTC)[reply]

Instead of saying which is larger or more voluminous, I rewrote the sentence to provide Everest's elevation as a yardstick --- sidestepping awkward OR into which is truly bigger. —hike395 (talk) 05:37, 6 February 2013 (UTC)[reply]

Read the last reference.Geological Survey Professional Paper, Volume 1350, Issue 1 In particular, go back a few pages from where the link goes to, to Figure 2.6. The others presumably took it from this (they are neither independent nor specialists), and are not wrong in the underlying facts but consistently do a very poor job of translating it into common language. The crust is depressed, but not the seafloor; it's not seafloor when it's got a mountain sitting on top of it! Lava has filled in the depression to the point where little or no depression is noticeable on the seafloor. And as hike395 noted, there was mixing of different measures of height, as well as of km/mi and m/ft. I did some more rewriting to clarify Mauna Loa from seafloor to peak vs. Everest from sea level (which is the usual comparison), and mentioned the underground bulk afterward. See what you think. KarlM (talk) 09:16, 6 February 2013 (UTC)[reply]

Indeed, the USGS source says crust, not sea floor. I agree that crust is clearer and less misleading. —hike395 (talk) 13:37, 6 February 2013 (UTC)[reply]

This article states that "Mauna Loa is the largest subaerial volcano in both mass and volume, and has historically been thought of as the largest volcano on Earth; however, the recently discovered submerged supervolcano Tamu Massif is many times larger." (bold added by me).This text is based on, and cites, the same source as the Tamu Massif article (which currently states that "Tamu Massif is the largest known volcano on Earth and comparable to the largest known in the solar system, measured by area.").

The source for these statements is an article New Giant Volcano Below Sea Is Largest in the World published on 5 September 2013 on the National Geographic website.

The media interest was triggered a paper by Sager et al. on the Nature Geoscience website, published on 5 September 2013 but corrected on 6 September 2013. The abstract of this Nature Geoscience article states "We suggest that the Tamu Massif could be the largest single volcano on Earth and that it is comparable in size to the largest volcano in the Solar System, Olympus Mons on Mars."

Sager et al. suggesting/claiming that "the Tamu Massif could be the largest single volcano on Earth" (bold added by me) and the media telling us that the Tamu Massif is the largest single volcano on Earth, are two different things.

Tamu Massif is larger than Mauna Loa but is Tamu Massif a single volcano? It could be, but we still cannot say for sure. The scientific jury is still out, because it has not even studied the two-day-old claim yet. The article by Sager et al. is more the start of the process of assessment than its end. Assessment by other scientists of evidence presented in the Sager et al. paper could show that Tamu Massif is not what has been claimed. Tamu Massif may not actually be the largest volcano on Earth, and Mauna Loa could still be the largest volcano on Earth. The media have prematurely reported the suggestions about Tamu Massif as fact. To repeat this in the Mauna Loa article and the Tamu Massif articles on Wikipedia is also premature. Until the findings are confirmed by other geologists, Mauna Loa being replaced by Tamu Massif as the largest volcano on Earth should be described in the Wikipedia articles as a suggestion/claim/possibilty, not a fact. It's too early for Wikipedia to treat Sager et al's claim as fact. I suggest that the Mauna Loa article in Wikipedia should be changed to reflect this uncertainty. GeoWriter (talk) 20:17, 7 September 2013 (UTC)[reply]

Using the equation for a volume of an elliptic cone, Tamu Massif would have a volume of approx. 330,000 cubic kilometres (79,000 cu mi), which would be larger in volume than Mauna Loa by more than a factor of 4. So, if the Tamu Massif single volcano hypothesis holds up, the statement that Mauna Loa is the highest volume and mass volcano on Earth will also be false.

I would suggest keeping Mauna Loa as largest in the lede, but put a footnote in the article about Tamu Massif and the possibility of it being much larger. —hike395 (talk) 08:16, 8 September 2013 (UTC)[reply]

Highest subaerial mass and volume. I didn't look at any of the papers but the claim seems "legit". Looking at the abstract (I thought academic paywalls were falling out of fashion?) the language used is "We show that the Tamu Massif is a single, immense volcano, constructed from massive lava flows that emanated from the volcano centre to form a broad, shield-like shape..." You're right that the burden of proof is higher in science than in popular journalism, but the evidence seems solid enough that until proven otherwise I would like to keep the lead formatted the way it is. It is a bit of a scientific overthrow, though. It's not often do things that are measured in the millions of years old lose size competitions on our pale blue dot; goes to show how much more there is to discover about our ocean depths, I guess. ResMar 21:20, 8 September 2013 (UTC)[reply]

It is a bit sensationalist; as has been pointed out, while the data suggests that Tamu Massif is the largest, the sampling method used has multi-kilometer gaps in the data, which allows for the possibility of Tamu Massif being the product of multiple volcanoes. We aren't likely to get better data for quite some time. Titanium Dragon (talk) 00:17, 9 September 2013 (UTC)[reply]

Removed the Tamu Massif bit from the lead and retained "historically considered..". The previous was rather irrelevant for the lead - maybe a note w/in the body once the Tamu info is verified/corroberated. Tamu is Jurassic whereas Mauna Loa remains active. Vsmith (talk) 16:17, 25 September 2013 (UTC)[reply]

the Mauna Loa magma chamber extends about 3 miles below sea level — Preceding unsigned comment added by 66.199.196.130 (talk) 17:17, 13 February 2015 (UTC)[reply]

the Mauna Loa magma chamber extends about 3 miles below sea level and its a bit taller then mt.everast. its 60 miles long and 30 miles wide. — Preceding unsigned comment added by 66.199.196.130 (talk) 17:19, 13 February 2015 (UTC)[reply]

Hiking the area can cause serious sickness. This should be included in the Hazaard's section...

- http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4244895/. SChalice 04:26, 29 July 2015 (UTC)[reply]

Update all volume and size text to reflect that Mauna Loa is once again viewed as the largest volcano. Also remove or edit the bit about the Tammu Massif as it has been discovered that it is not actually a volcano at all. Sources: https://www.nature.com/articles/s41561-019-0390-y

News Publication here as well: https://www.livescience.com/65897-largest-volcano-record.html Woofde (talk) 22:58, 9 July 2019 (UTC)[reply]

 Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. - FlightTime (open channel) 18:47, 19 August 2019 (UTC)[reply]

In the "Human History" section, "European Summiting Attempts" subsection, the fifth paragraph needs attention. The first sentence, "The next successful ascent was made on January 29, 1834, 40 years later, by the Scottish botanist..." looks like it was written before the preceding paragraph was added. Recommended: remove "40 years later" (especially as the 40-year gap is already mentioned once at the end of the third paragraph and again after the fifth).

Also in the fifth paragraph: change "...stayed overnight to make measurements of the summit caldera's proportions and record barometric data on its height, both now known to be widely inaccurate" to "...wildly inaccurate" (one gets the impression that's what the author meant).

Also in the fifth paragraph: change "several months later his body was mysteriously discovered crushed in a pit besides a dead wild boar" to "...his body was discovered mysteriously crushed in a pit beside a dead wild boar" (note both placement of the word "mysteriously" and replacement of "besides" with "beside").

Great article! 2603:3004:6B4:7000:3C9D:D9B8:9BC:C6AF (talk) 17:59, 17 August 2019 (UTC)[reply]

 Done --Trialpears (talk) 18:48, 18 August 2019 (UTC)[reply]

In the Structure section reference to Puu Ki is missing, see Littoral cone, it is located southwest on Mauna Loa. Imho adding it to the paragraph already explaining Puu Ulaula should not hurt. Eventually linking to Littoral cone and adding Puu Ki as an external ref. --Cmuelle8 (talk) 21:25, 18 October 2020 (UTC)[reply]

There are lots of other summits on Mauna Loa unmentioned, see radius search around Puu Ki, but mentioning Puu Ki is of particular interest, because it is referenced in other articles, Topographic isolation and Littoral cone. --Cmuelle8 (talk) 22:12, 18 October 2020 (UTC)[reply]

I am reviewing this very old FA as part of WP:URFA/2020, an effort to determine whether old featured articles still meet the featured article criteria.

• There is an inconsistent citation style, particularly with author names, but everything needs to be checked.
• Not a high-quality source: "Mauna Loa, Hawaii". Peakbagger.com. Retrieved 12 December 2012.[self-published source?]
• Who is this, what makes it high quality? John Seach. "Mauno Loa Volcano – John Seach". Retrieved 24 January 2013.
• Excessive off-topic detail in Wilkes expedition.
• Updating and checking throughout needed. As but one example, https://gml.noaa.gov/obop/mlo/ says that the Observatory is at 11,125 feet. We link to a ten-year-old archive, and use a different number. All older archived info should be checked as this FA is approaching two decades old.
• Dead links: https://hvo.wr.usgs.gov/maunaloa/ Means I can't verify if this is still true from the source given: including 33 eruptions since the first well-documented eruption in 1843 BUt I did find that info here: https://www.usgs.gov/observatories/hvo/active-volcanoes-hawaii
• Here's an entire paper on the 1880 eruption, plucked from the over 4,000 sources returned by google scholar since 2017 only; is anyone keeping this article updated?

A Featured article review is probably necessary here, unless someone can update the article. SandyGeorgia (Talk) 03:16, 18 December 2021 (UTC)[reply]

I deleted the Seach source -- it seems like a self-published website and the person does not seem to be a trained volcanologist. The statements that used that particular website as a source also referenced other, higher quality sources so nothing lost removing it completely. I am hoping to look at some of these other issues raised here later as time permits during the holidays. Aoi (青い) (talk) 09:50, 18 December 2021 (UTC)[reply]

Thanks for taking this on! My list is samples only, and indicate a read-through of everything and check for newer sources might be called for. I can’t keep every URFA review watchlisted, so please ping me when you are ready for a new look. SandyGeorgia (Talk) 15:10, 18 December 2021 (UTC)[reply]

Just leaving a note to acknowledge that I saw this. Thanks for pointing these issues out. I'm slowly going through the article sentence by sentence and source by source in my sandbox, though I probably lack the expertise to evaluate some of the more technical geophysical statements in the article. (Perhaps more significantly, I also am not familiar with the URFA process, so I appreciate your patience!) Thanks, Aoi (青い) (talk) 07:03, 21 December 2021 (UTC)[reply]