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A Modest Proposal

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Second-year undergraduate student in Earth Systems Science and Engineering, and Statistics, at the University of Michigan in Ann Arbor. Currently performing analysis of high-frequency variations in glacier terminations in Greenland. Contributing author for skepticalscience.com

  • Which trend in sea level do "skeptics" want to use?

    This question was asked recently:

    c8kslxq

    (the above is a tinyurl append to the question, I am not sure if Y!A will allow me to include a full link, will add one in a comment anyway)

    I answered and have since been blocked. I am not sure what was so contentious about my answer, other than providing good reasons why the questions were badly premised - however I can still sign out and look at the question, just can't edit my answer any more.

    One of the recent edits by the author Pat was to suggest that the 200mm sea level rise since the beginning of the tide record shows a trend of 1.54 mm/year, I suppose to be a big "AHA!" to me in that continuing that trend produces an even *smaller* GMSL change in a 100 years than the trend over the satellite record.

    But, the blog post from Tamino's clearly shows an acceleration in the trend to roughly match the trend over the satellite period, so I see this as dishonest.

    I also see it as self-defeating, since it's now so easy to show that the trend of 1.54 mm/year has been essentially doubled. It only helps the narrative that sea level trend is increasing, to try to extrapolate the 1.54 mm/year trend - which would "skeptics" _really_ like to use?

    7 AnswersGlobal Warming8 years ago
  • How can a President end an executive branch?

    I recall, as an example, that Governor Perry said during his campaign he would end some agencies, like the Department of Education. What process would have to be followed for that to happen? What I'm especially curious about is what role Congress would have to play in that, since there are obvious litigation relationships.

    Thanks ahead of time.

    1 AnswerGovernment8 years ago
  • How do lowess smooths work with regards to the ends of time series?

    I'm applying a lowess smooth to ocean heat content data to see how the last several (~8) years behave with some filtering, but a running centered (say, 5-) year moving average seems to show a decrease in the rate of increase of the series (deceleration) toward the end, whereas the lowess shows a continual increase. Indeed the data from ~2003-on is relatively flat, but that flatness is very dependent on start point - including just a couple preceding months in the data for a linear fit causes the trend to at least triple in value. The general shape of the unfiltered data seems to be that of a rather steady and sharp increase through the 1990s, and then it hits what you might call a ceiling in 2003, where the trend since is shallow.

    How exactly does a lowess filter behave? I have been adjusting the portion of data the filter uses, R by default uses 2/3 but that's far too much. Even down to 1/20 though, the data doesn't seem to show that leveling, does the filter toward the endpoints rely on the trend of preceding points? What's exactly going on with the lowess filter?

    1 AnswerMathematics9 years ago
  • Statistics question on frequency response functions...?

    I am in the works of creating a response to a blog post in which the author uses sun spot data and sea level trend data to show a correlation between the two. However, the sea level trend data was obtained by applying a moving linear fit (least squares) across ten consecutive points (so, window is 10-points long).

    Does the FRF associated with a moving linear fit tend to magnify periods at frequencies sized the same as the choice of window (so, ten-point window amplifies periods close to 10)? It seems to be the case when I apply such a process to random data and put the linear fit slope values through a periodogram. The random data does not give significant peaks, but with a 3-long window I get large peaks at ~3, a size 7 window ~7, so on. It's all from the same dataset too.

    I could just put the sun spot (or perhaps it would be better to use total solar irradiance, which I also have) data and detrended global mean sea level data through a cross-spectral analysis, and I'm working on figuring out how to do that (I'm a freshman in college and have only a general grasp of these concepts). If anyone has some insight on how the FRF for a moving linear best fit behaves though relative to the window size, that would be very appreciated.

    1 AnswerMathematics9 years ago
  • Will skeptics be happy with the new HadCRUT4 because it now includes data in regions previously unobserved?

    (not observed well, anyways - sorry, character limit kept me from specifying).

    Or, will they say that the record has been tampered with to show warming, since these new stations are from Russia and other northern latitudes? I.e. the Arctic?

    http://www.metoffice.gov.uk/media/pdf/9/s/MOSAC_16...

    http://www.metoffice.gov.uk/media/pdf/1/e/Presenta...

    11 AnswersGlobal Warming9 years ago
  • Can basic solutions not experience acidification?

    FWIW, I'm assuming "basic" as in relative to pure water. For a very pertinent example, the ocean, which has a pH of >8. Can the ocean not experience acidification?

    Could someone enlighten me on where I am wrong in my previous question? It would seem that other answerers like to say I am but not actually explain themselves. Granted, I have not yet given them time to respond, but I'd like a third party opinion all the same.

    http://answers.yahoo.com/question/index;_ylt=AruIX...

    1 AnswerChemistry9 years ago
  • Do deniers understand the difference between pKa and pH?

    In relation to this question:

    http://answers.yahoo.com/question/index;_ylt=An1J7...

    One denier stated the all-too-common myth that to be called "acidic," something must have a pH of <7.0.

    For those of us that took chemistry, we all know that 7.0 is the pH of pure water, which can be traced back to the pKa of water, which is about 15.8. As another boring and redundant refresher, pKa is the ACTUAL measure of acidity, and is useful only in a relativistic sense. For example, HCl is very acidic in relation to water or benzene, though it is more BASIC (again, boring redundancy, I know, let me finish...) than H2SO4. Benzene, in turn, is more acidic than methane.

    Using pure water is simply a nice metric to compare against, since chemicals are often dissolved in water. However, to say that something cannot be acidifying because it is more basic than pure water shows a complete lack of understanding of basic concepts taught in every Chemistry 101 class.

    Do deniers understand this difference between pKa and pH, and what "acidic" and "acidifying" actually mean?

    7 AnswersGlobal Warming9 years ago
  • Does this XKCD cartoon summarize the "issue" that comes up, of 0.01% v. 40%?

    http://xkcd.com/985/

    i.e. the distinction between percentages and percentage points?

    5 AnswersGlobal Warming9 years ago
  • What century is the Yahoo! staff writer living in who wrote this for the present article on the homepage?

    This article:

    http://health.yahoo.net/news/s/hsn/stressearlyinpr...

    and the staff member who wrote the snippet seen on the homepage says this about the study in question:

    "How stress can affect baby's sex

    Pregnant women exposed to certain factors are more likely to deliver girls, a study suggests."

    The study actually concludes that stress leads to higher rates of premature birth and also a decrease in the male/female birth proportion, likely due to males being more impacted by stress because they require more resources from the hosting mothers (since they are bigger; the article discusses this).

    When was the last century when such ideas as outside factors could affect a baby's sex were accepted? The 1800s? 1700s? Do the people who work for Yahoo! even read the articles they are writing these snippets for?

    2 AnswersMedia & Journalism9 years ago
  • Why do deniers feel the need to lie in order to push their viewpoints?

    Such as in the drivel that appeared in this article at the Washington Post, which takes quotes from several different emails out of context and then pastes them to give the impression they're all about the same context?

    http://www.washingtontimes.com/news/2011/nov/29/a-...

    Bonus Question - does anyone else notice the irony in him calling the scientists frauds?

    11 AnswersGlobal Warming9 years ago
  • Where would I be able to purchase a water-cooled radiator suited for removing ~5 HP of power?

    I need to find a small radiator for each of two electric motors that will radiate 10 HP between themselves (so, 5 HP per). However, most of the radiators I see for sale online appear to be for machinery that radiates more power than this, and I cannot find options that would be sized close to what I need. Does anyone have any clues on where I might be able to find a suitable radiator?

    1 AnswerEngineering9 years ago
  • Where would I be able to purchase ~40 watt solar panels at low cost?

    For a project for my engineering class, we have to design and scope out the price for a solar-powered item. Ideally we would be able to give the lowest figures possible before having to argue for economies of scale, though I am not very sure where to start. I have been able to find 130 watt systems for roughly 3.5 dollars per watt, though I don't need that much power and have been unable to find smaller power systems that cost near that range.

    Efficiency isn't necessarily our goal right now, just cost. What websites or companies would be able to give me the quotes I'm looking for?

    7 AnswersGreen Living9 years ago
  • Are fake skeptics threatened by BEST confirming the land temperature record and marginalizing UHI effect?

    Why else would they attack Muller and BEST otherwise? I thought that the issue all along never was really about whether the planet was warming (sic).

    What legitimate complaints do "skeptics" have against Muller or BEST that pertain to the quality or methods of the analysis? If nobody here has any themselves, what "skeptics" have brought up valid and supported points that you could perhaps link to here?

    14 AnswersGlobal Warming9 years ago
  • Last question, no more games, and I have links now: if the lag is not global, why do skeptics cling to it?

    [This is a repost of this question, the previous one did not post due to hyperlinks. I will post obfuscated links in updates below.]

    Sorry for not following up before, I became quite busy outside of Answers so that I couldn't keep this flowing. In either case apparently the best thing to do would be to make my point as clear as possible:

    For some background info, Petit et al 1999 in Nature[1] was one of the first papers to study Vostok - aside from only looking at deuterium (temperature proxy) and CO2, they looked at d18O (used as a proxy for glacial ice melt and hydrological - water - cycle behavior) and methane. They suggested that since methane corresponded to the most recent northern hemisphere warming (from the last glacial into the Bölling/Allerød; this signaled the start of the warming phases for the NH for the last termination) as per records seen in Greenland, then methane could be used as an indicator of northern hemisphere deglaciation events. This makes sense, since the northern hemisphere holds the vast majority of methane-enriched tundra and clathrates, such as can be seen here[2].

    Caillon et al 2003 similarly assumed the same relationship as Petit et al, and found that the methane and Argon records in Vostok suggested that the northern hemisphere lagged behind the warming in Antarctica by about 6000 years.

    As we all know, CO2 lags behind deuterium in Antarctica by about 800 years - since we also know that CO2 and methane are well-mixed greenhouse gases (even ignoring the greenhouse gas part, we know that they will mix relatively evenly in the atmosphere in a matter of a few years), that would indicate that CO2 led northern hemisphere warming. What more, newer dating techniques resolve the methane records between the northern and southern hemispheres[3].

    What is also important to note in the above paper is the time of transition for the northern hemisphere to the BA, and the time of transition for Antarctica to the interglacial. The glacial period to BA occurred around 14740 ±60 years before present (Table 6), whereas Antarctica started warming around 17,900 ±300 years before present (page 16). Thus, again, the northern hemisphere warmed well after Antarctica showed warming.

    Toggweiler and Lea 2010[4] suggested that the causal link between the two is that southern hemisphere warming, started by redistribution of heat from orbital cycles (Milankovitch theory) led to degassing of CO2, which along with factors like albedo decrease led to northern hemisphere warming.

    Anyways, the lag between the northern hemisphere warming and southern hemisphere warming is quite well established (as well as glacial mass in general - I will try to get a good paper discussing that, I had found one but lost it), and it is much larger than the lag between southern temperatures and CO2.

    Would skeptics have a problem accepting this? That CO2 lags temperature in the south, but not the north?

    What step along the line of this reasoning, too, would skeptics have a problem with?

    orbital forcing => southern warming/northern cooling => upwelling of CO2 => loss of ice sheets => warming in northern hemisphere from both the increasing GHG and loss of ice sheets => methane emissions

    3 AnswersGlobal Warming9 years ago
  • Since my most recent question RE CO2/temp lag didn't post due to hyperlinks, can people find it in my profile?

    Sorry about the lag (haha) in following up with another question. I tried to post another but apparently I'm running into problems with it actually getting onto the page. I think it might be accessible through my profile, if people would like to answer it. If not, I'd appreciate some feedback on that so I can try to post it again, but maybe without hyperlinks or with parsed links.

    However, since this actually has to be a question:

    What are your views on the results of the BEST study, which ultimately concluded:

    - the station temperature records are robust;

    - removing the "not very rural" stations from the mix actually results in an *increase* in the derived trend (i.e. UHI cools... weird, huh?).

    A follow up to the last point, what mechanism could explain the result that cities seem to introduce a cooling bias to the record? One I have heard speculated at SkS for instance is that cities don't promote the accumulation of water vapor or evaporation above them, so that might lead to less of a greenhouse effect from that.

    5 AnswersGlobal Warming9 years ago
  • Follow up question: what region of the planet do ice cores from Antarctica give us temperature proxies for?

    Then, I'd like people to give this another go, I'll admit the first question may have been too vague:

    Why do CO2 levels lead *northern hemisphere* deglaciation? What mechanism would explain that?

    Perhaps a different question so everyone can have a better time seeing the angle I'm coming at: are deglaciations caused by synchronized global warming?

    5 AnswersGlobal Warming9 years ago
  • Why do CO2 levels historically lead northern hemisphere temperature rise during deglaciation events?

    I was wondering if an AGW skeptic could answer this for me.

    14 AnswersGlobal Warming9 years ago
  • How do you define secularism?

    At our chapter for the Secular Student Alliance in the USA, we had a discussion last week about what we all thought individually about what "secularism" is, and also to try to get a unifying definition that we could all agree on because we are, well, the SSA.

    Some mentioned that it is the promotion of the divorce between religion and politics - others suggested an extension to all walks of public life (as in, secularism should be the separation of your religious ideals with what you do in a public arena, as opposed to private).

    Going off the former, some also brought up the point that secularism, as it applies to voters, is a tricky situation: should eligible voters vote based on their religious beliefs? Is it OK if religious beliefs have a role at all, even if not dominant? Is there a disconnect too, as we're choosing representatives that may not act according to our religious beliefs anyways?

    Also, what if there are very good non-religious reasons for supporting a politician/political goal, even though your main personal reason might be religious in nature?

    These were all points brought up during our discussion (and unfortunately we strayed from a few at times, but oh well). How do you define secularism, and to what extent do you think a "secular" person should apply that value?

    5 AnswersReligion & Spirituality9 years ago
  • Can someone clarify the dynamics of salinity and ice formation in the context of the Younger Dryas for me?

    As an example, anyways.

    In responding in a couple comments to a question asked recently about the likelihood of global warming leading to an ice age:

    http://answers.yahoo.com/question/index;_ylt=AtM79...

    I recalled hearing about a past analog for this type of event, and figured (correctly) that it was the Younger Dryas.

    The wikipedia entry for it, specifically the section about its cause (here):

    http://en.wikipedia.org/wiki/Younger_Dryas#Causes

    says:

    "The global climate would then have become locked into the new state until freezing removed the fresh water 'lid' from the north Atlantic Ocean."

    So I just wanted to make sure I understood this - mixing freshwater would lead to a shutdown of the thermohaline circulation which would lead to less heat being transferred northward, which would lead to formation of ice. As the ice forms, the salinity of the ocean increases again (since the lattice structure rejects dissolved ions), and thus when ice reaches a certain extent the previous thermohaline circulation can reform again.

    Is that a good summary of this effect? I'd appreciate some feedback on this.

    4 AnswersGlobal Warming9 years ago
  • (Without wanting to assume a conclusion here... RE CERN experiment) Is the possibility of...?

    ...previous miscalculation of the speed of light being considered as another explanation for the supposed faster-than-light neutrinos?

    I'm not very familiar at all with the specifics of how the speed of light is defined, but if we propose for example that b < a, and a = 6 but b = 7, then we could conclude that b = 7 is wrong, but it is also just as likely that our definition a = 6 is wrong, and thus not necessarily the relationship b < a.

    Or, of course, that the relationship is wrong, but again I don't want to assume conclusions.

    Just for the sake of concept anyways. I guess an underlying question that needs to be answered before that previous question can be is: how is the speed of light determined? Also, what are the sources and sizes of experimental error for that?

    1 AnswerPhysics9 years ago