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Ask Dr. Bryan Killett About Climate Change and GRACE
Bryan Killett is a physicist working on the Gravity Recovery And Climate Experiment (GRACE) for NASA's Jet Propulsion Laboratory. GRACE is a joint mission of NASA and the German Aerospace Center which collects satellite data to learn about Earth's changing gravity field, specifically the high frequency changes associated with ocean tides. As the high tide comes in, more water is present, so gravity in that location is temporarily strengthened. These changes are detected with GRACE and used to improve ocean tide models. Dr. Killett provides the open source (GPLv3) code used to process GRACE data on his home page. Bryan has agreed to take a break from measuring gravity fields and answer your questions about GRACE and the climate changes it has revealed. Feel free to ask as many as you like but please confine your questions to one per post.
If you had unlimited resources and unlimited materials (planet sized masses, black hole measuring devices, you name it), what hypotheses and tests would you construct to give us more information on what precisely gravity is?
My work here is dung.
What does this have to do with Climate Change? There's no reference to it in any of the pages linked. I assume mapping tides is important if sea level rises, but that's just a guess.
We've seen a lot of surface melting on Greenland over the past few weeks. Does GRACE provide enough detail quickly enough so to quantify that melting, and shed any light on how well we understand ice sheet melting dynamics?
GRACE's main use in climate change is to detect the loss of mass from melting glaciers (mostly in Greenland and Antarctica), which results in sea level rise. It can also help map surface currents in the ocean, and track the motion of water through the hydrological cycle.
Because they actually understand science, in contrast to, well, others..., no?
Ubi solitudinem faciunt, pacem appellant.
Yes, it was totally out of left field. I responded in an internal JPL email, and copied the email to my (other) website.
-Bryan Killett, aka khayman80, aka Dumb Scientist
How have GRACE GPS radio occultation results compared with TEC data from other observations at the same time and along nearby paths (from GPS ground sites, from other radio occultation observations from e.g. C/NOFS or COSMIC, etc.)? Is the GRACE GPS R/O data publicly available? If so, with how much delay? Thanks.
Should science drop the "Climate Change" mantra and get back to basics like pollution and sustainability? I believe climate change has become a political boogeyman and that science would be better off focusing on more clearly defined goals (making renewable energy usage more affordable etc).
I think you're under the mistaken impression that "scientists" all do one thing at a time.
We already *are* focussing on renewable energy, improved drugs, advances in medicine, the search for the Higgs field...
It's only the media and various special interests with a financial stake in discrediting the inconvenient results of climate science that create such a stir. In the actual world of science and research, climate science is just a small part. It gets far more media attention in proportion to the work and money being spent on it.
No, tides are caused by gravity, which is caused by mass. Solar storms are violent, but the amount of mass involved is miniscule compared to that of the Sun. A very powerful solar storm wouldn't even cause a small tidal shift.
Why are aeronautical engineers, astrophysicists, rocket scientists, etc. involved in perpetuating a political agenda based on bad "science" for an administration that refuses to fund the organization's actual purpose?
I'll ask the opposite question: why shouldn't aeronautical engineers, astrophysicists, and rocket scientists be involved in trying to make unambiguous measurements of a critical issue, to try to resolve key questions in a way that's independent of computer models or temperature measurements? Making an independent measurement of key scientific claims using a different technique is pretty much the gold standard of science.
http://www.geoffreylandis.com
One modest example is extracting energy from the ocean tides. I've explained that harnessing tidal power would actually move the moon farther away from the Earth, even faster than its current ~3.8cm/year recession rate. Tidal amplitudes are influenced by the coastlines and bathymetry, so in principle we might eventually be able to change the tidal amplitudes in some location (bigger for more tidal power, smaller for easier navigation) by carefully modifying the bathymetry.
Just to clarify the summary, GRACE primarily studies long-term changes in water storage. It's just my research in particular that focuses on high frequency signals like ocean tides. Also, the open source code mentioned in the summary is just used to produce my personal results, not the official GRACE solutions.
-Bryan Killett, aka khayman80, aka Dumb Scientist
" And "skeptic" theories tend to hit in the 30-50ish% range, depending on the extent to which they allege conspiracy."
Alleging conspiracy is not a valid measure of pseudoscience. While it is true that popular culture derides those who they perceive to be "conspiracy theorists", alleging conspiracy has absolutely nothing to do with the underlying science. Nor, for that matter, is a bald allegation any evidence either for or against any actual conspiracy.
While it is fun to laugh at such theories, it is important to remember that the actual historical record contains a huge number of documented and proven conspiracies, many small, but also many great.
how do you define 'climate' as opposed to 'weather'?
Because it's not their field of expertise.
Making gravity measurements, building the instruments to make gravity measurements, and the rockets to fly them, ARE their respective fields of expertise.
Because they should be focusing on what my tax dollars pay them to do - develop methods for space exploration and explore space.
Your tax dollars pay them to build and fly the GRACE mission and many other Earth-observing missions. So they already are focusing on what their tax dollars pay them to do. All of which, by the way, fall under NASA's mission statement.
Oh gee, another moron with an 8th grade misunderstanding of what science is. "No repeatable experiment"? By that criterion, astronomy, geology, etc. aren't science. "No testable hypothesis?" First, climate change isn't one single phenomenon with one single test. It's a series of interrelated phenomena, each of which are individually testable, starting from the infrared absorption properties of the CO2 molecule all the way up to stratospheric cooling, ocean warming, etc. "No science"? Doesn't even deserve a response.
Scientific discovery using spaceborne instruments, such as GRACE, is part of NASA's core mission.
I'll ask the opposite question: why shouldn't aeronautical engineers, astrophysicists, and rocket scientists be involved in trying to make unambiguous measurements of a critical issue, to try to resolve key questions in a way that's independent of computer models or temperature measurements? Making an independent measurement of key scientific claims using a different technique is pretty much the gold standard of science.
Because it's not their field of expertise.
Precision measurements of the gravity field of the Earth using spacecraft? It most certainly is their field of expertise.
Because they should be focusing on what my tax dollars pay them to do - develop methods for space exploration and explore space.
Here is the wording of the Space Act of 1958, which established NASA and listed its mission and objectives. After declaring that NASA will be a civilian agency to undertake aeronautical and space activities of the U.S. "for the benefit of all mankind," it states: ..."
"The aeronautical and space activities of the United States shall be conducted so as to contribute materially to one or more of the following objectives:
(1) The expansion of human knowledge of the Earth and of phenomena in the atmosphere and space. (2)
Expanding human knowledge of the Earth and phenomena in the atmosphere: yes, the GRACE objectives fit into the mission that NASA is explicitly instructed to do.
Reference: http://history.nasa.gov/spaceact-legishistory.pdf
http://www.geoffreylandis.com
It's true that sometimes conspiracies actually exist. However claims that mainstream science is engaged in a conspiracy to suppress some bit of research makes it more likely to be pseudo-science, because (far) more often than not the claims are false. It's not a guarantee that it's pseudo-science but it is a red flag that indicates further examination may be required.
Fanatically anti-fanatical
But this isn't scientific discovery, since gravity was already discovered 150 years ago.
Oh good grief. Talk about tortured logic.
Let me explain this to you simply: the scientific purpose of GRACE is not to "discover gravity". It is directly to measure the Earth's gravitational field. Indirectly, it is to discover a lot of things about geoscience (ice dynamics, hydrology, etc.).
I may also point out to you that (as has been noted elsewhere in the comments) the Space Act which chartered NASA explicitly states that part of its mission is to expand human knowledge of the Earth (using spaceborne technology).
Didn't even click the link. Didn't present your own findings. Trolling concluded.
To respond to your request:
Pseudoscience displays an indifference to facts:
DOES NOT APPLY climate change, as data driven observation is at the core of the argument. New facts brought up by critics are addressed with data.
MAY APPLY TO "skeptics", depending on exactly what they are skeptical of. It is an undeniable fact that, for example, temperature measurements are going up quite rapidly year-to-year.
Pseudoscience "research" is invariably sloppy
Given the criteria listed in the linked article: DOES NOT APPLY to climate change. An opinionated counter-argument could be given, if one were unwilling to examine the definition listed with any seriousness. Global examination of carbon/temperature data with a wide variety of tools, cross-indexed with each other, tabulated, peer reviewed, and published in complete detail does not qualify as sloppy. Sorry.
ALSO DOES NOT APPLY to "skepticism" in any meaningful way.
Pseudoscience begins with a hypothesis—usually one which is appealing emotionally, and spectacularly implausible—and then looks only for items which appear to support it.
COULD BE CONSTRUED TO APPLY to climate change: I think we can agree "we're all going to burn due to our negligence" is an emotionally appealing hypothesis. I don't really think the hypothesis came before the climatological observation, looking at the early papers in google scholar, though. Lower temperature years are included in every single report on global warming, in spite of the fact that, at face value, that would appear to a layman to undermine the hypothesis.
COULD BE CONSTRUED TO APPLY to "skeptics": I think we can also agree "we don't have to change anything because we're not doing anything wrong" is also emotionally appealing. Being that this is the null hypothesis position, it's fair to say that the "hypothesis first" doesn't really apply. However, selective examination of data IS an extraordinarily common argument from this camp, and to treat it as a non-component would be disingenuous. (i.e. "it was cold in winter")
Pseudoscience is indifferent to criteria of valid evidence.
DOES NOT APPLY to climate change. Not in the slightest. "stories" do not make up the basis of support for the theory, known thermodynamic effects, and temperature trends do.
MAY APPLY to some forms of "skepticism". As per above "winter is cold" type arguments, are strictly anecdotal, and do not actually examine the temperatures in winters globally compared to previous years.
Pseudoscience relies heavily on subjective validation.
DOES NOT APPLY to climate change. The verification comes entirely in the form of statistical analysis of temperatures versus previous predictions. Relatively accurate, but requiring improvements in predictive techniques.
DOES NOT APPLY to "skepticism" BUT IN A VERY BAD WAY because no counter claims or predictions to test. The null hypothesis of "no change" is clearly invalidated, but no valid alternate predictions are given instead. This is a serious sign of pseudoscience.
Pseudoscience depends on arbitrary conventions of human culture, rather than on unchanging regularities of nature.
DOES NOT APPLY TO EITHER, if you examine the listed definition in my link, this is about data being purely subjective and prone to multiple understandings depending on cultural factors like language.
Pseudoscience always achieves a reduction to absurdity if pursued far enough.
DOES NOT APPLY TO EITHER. Feel free to contest this if you want.
Pseudoscience always avoids putting its claims to a meaningful test.
DOES NOT APPLY to climate change, predictions from 10,20, and 30 years ago are all being tested and examined today.
APPLIES TO "skepticism". "Skeptics" tend to hide behind vague claims such as "it's a natural cycle" without providing assertions about what that means in terms of cl
Feel free to contend points you disagree with.
I might as well, since you went to so much effort to put this together. For the record, what I was keying on were the six points in the "Science / Pseudoscience" chart, and it was unnecessarily disingenuous of you to claim that (1) I didn't click on the link (I did), and especially that (2) I was trolling (don't be a dick).
Pseudoscience relies heavily on subjective validation.
DOES NOT APPLY to climate change. The verification comes entirely in the form of statistical analysis of temperatures versus previous predictions. Relatively accurate, but requiring improvements in predictive techniques. DOES NOT APPLY to "skepticism" BUT IN A VERY BAD WAY because no counter claims or predictions to test. The null hypothesis of "no change" is clearly invalidated, but no valid alternate predictions are given instead. This is a serious sign of pseudoscience.
One argument heavily propagated for AGW is "consensus" of scientists or "peer-reviewed papers". A fallacious argument on its face, and while numbers are not subjective, statistics and the criteria to generate them, in this case, often are. Also, your argument about "no predictions to test" applies equally to climate change, as the "predictions" are either based on a probability range too wide to really evaluate, or they are not met before "adjustments" are released to better match observations.
The other subjective criteria often used in the popular press involves selective evidence. For instance, the discredited paper that indicated the polar bear population was endangered, which later proved to be inaccurate, so instead the narrative has changed to "reduction of the arctic ice hunting grounds of the polar bear could eventually lead to a reduced population.
Pseudoscience always avoids putting its claims to a meaningful test. DOES NOT APPLY to climate change, predictions from 10,20, and 30 years ago are all being tested and examined today. APPLIES TO "skepticism". "Skeptics" tend to hide behind vague claims such as "it's a natural cycle" without providing assertions about what that means in terms of climate.
I don't accept your premise about skeptics, and while you are correct that climate change predictions are tested and examined today, they don't really show a compelling amount of accuracy. Aside from that, skepticism of climate science is mostly about challenging a theory, not advancing one that is more accurate, but simply pointing out that there are too many unknowns to make accurate predictions.
Pseudoscience appeals to the truth-criteria of scientific methodology while simultaneously denying their validity. DOES NOT APPLY to climate change: existing rules of invalidation are well accepted. MAY APPLY to some skeptics: for example the "winter was cold this year" people who ignore that it was extraordinarily hot the previous year are willfully ignoring invalidation on their own basis.
Um, if you listen to the latest news reports, they have a lot of self-proclaimed scientists claiming today that the heat waves and droughts the US is experiencing right now are clear evidence of climate change (and AGW at that). So I think both are guilty on that count.
You make some good points here, but, frankly, I don't think you can compare AGW vs. Skepticism of AGW as being separate disciplines that can be categorized separately as science or pseudoscience. Certainly Climatology is a science. And there is clear evidence of a global warming trend in the 20th century. I think the debate is about how much human activity is contributing to the changes, how much change is happening, and whether a major change in human activity can make a difference.
Theoretical physics is also a science, but there are different theories regarding why things happen. That doesn't make string theory pseudoscience and quantum mechanics more of a real science, it's just that the string theorists are trying to explain things outside the clear observations presented in the standard model.
"Somebody has to do something. It's just incredibly pathetic it has to be us."
--- Jerry Garcia
consensus
This talking point has always bothered me, if consensus is not part of science then why do scientists place so much importance on peer-review? Consensus is not a dirty word in science, it's the modern term for what Karl Popper called "the republic of science", it is a measure of agreement amoungst the experts in a particular field as documented in Journals and text books. It is the difference in confidence between the phrases "A scientists says" and "Scientists says".
[predictions] don't really show a compelling amount of accuracy
The one's I've seen from Hansen (1980's) and those from IPCC (early 90's) are all well within the error bars given with the predictions. Therefore they are accurate to within the stated margin of error which is all you ever get from a scientific prediction. Note that such predictions usually come in sets with different emmission senarios and it's common for intellectually dishonest people to ignore this and present a "worst case senario" prediction as a "most likely senario" prediction in an attempt to ether, discredit the work for political reasons, or try to scare people for political reasons, (depending on wich side of the politics they take)
Um, if you listen to the latest news reports, they have a lot of self-proclaimed scientists claiming today that the heat waves and droughts the US is experiencing right now are clear evidence of climate change.
There are psudeo-scientists on both sides of the political divide on this issue. I have followed the issue with interest since 1981, I don't recommend "news reports" as a reliable source of information about climate science (particularly in the US), and if you are a geek "El Reg" is also a noteable bottomless pit of misinformnation on the issue. I will however say that many reputable climate scientists have been predicting for at least the last decade that the US grain belt is in danger of sever droughts from AGW. The basic physics says the sub-tropical desert zone will dry out more and expand, while at the same time monsoons will become wetter. Both are an expected consequences of increased convection in the equitorial "Hadley Cells". This is complicated by the jet stream in the N. Hemisphere which can cause the western half of the US to be in drought while the other is flooded. Having said that, what is undisputable is that long term climate predictions are much more accurate on a global scale (global temp, humidity, etc) than regional predictions, regional predictions will always be more difficult and less precise.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
That might not have been a great example, even though it does illustrate the point.
I will put it a different way.
Let's say you're a professor, who has come to realize that his student's papers closely follow Sturgeon's Law (that is: 90% of them are crap).
So when a new semester rolls around, and his new students are turning in their first assignments, he scarcely bothers to look at them. Because he knows that they're all 90% crap. (I pulled a subtle switch on you here, in case you didn't notice.)
But later he realizes that a couple of the papers are real feats of genius, that might actually transform the field. (Maybe not likely, but possible.)
Because, see, although it is true that 90% of them were crap, you cannot judge them individually by that statistic. 90% of them in bulk may be worthless, but that says nothing about THIS paper you have in your hand. The statistic is worthless for judging it. The only way you will know for sure how good THAT paper is -- even if it is by someone you are familiar with and despise -- is to actually read the contents of the paper. Trying to assign the bulk statistic to the individual instance beforehand is simply not valid procedure. It doesn't work. Ask any statistician.
I was also amazed.
But for TapeCutter, I do have an answer to one of your questions:
The reason consensus is not science, is because it doesn't matter how many scientists agree that something is plausible; it only takes one counterexample to prove them wrong.
And it has often been INDIVIDUALS, outside the field, who have provided that counter-evidence. Such is the history of science. Recorded history is riddled throughout with individuals proving the "consensus" to be wrong.
Almost EVERY major scientific advance has come about as a result of a discovery that proved the status quo (consensus) wrong, to a greater or lesser degree. If that were not so, individuals would not make discoveries and science could not advance.
So, consensus is not science, because: it cannot be. That's not the way it works. It is not a democracy, it is a set of rules based on evidence. One "vote" can invalidate all the rest.