Significant Figures by Peter Gleick

Welcome to “Significant Figures”

Welcome to the first post in my new National Geographic ScienceBlogs column “Significant Figures.”  I look forward to sharing my thoughts with you on a wide range of environmental science-related issues, data, and people, and to a productive and constructive interaction.

My background? I’m an environmental scientist by training and inclination, with experience in engineering, hydrology, climatology, and interdisciplinary analysis. My research and writing have, for over thirty years, focused on water resources, climate dynamics and change, energy, risk assessment, and the synthesis and communication of knowledge at the intersection of science, economics, and public policy. I direct a non-profit research institute; regularly brief policy makers and speak to the public on issues of major concern in the field of environmental science; testify for state, national, and international proceedings; and far too infrequently bird (that’s a verb) and play the five-string banjo. I’m a member of the U.S. National Academy of Sciences and other professional scientific organizations in the geosciences. I’ve authored or co-authored nine books. My biographical information and publications list can be found here. Some of you may also be familiar with my writings from other outlets, from my peer-reviewed journal articles, to the research and analysis produced at the Pacific Institute, to the blog posts I’ve done at Forbes (archived here); SFGate “CityBrights” (archived here); and my Huffington Post column.

My focus here at ScienceBlogs will be topics related to the science and policy of water, energy, food, and climate. The themes of my posts will be “Significant Figures” in three meanings of the phrase:

First, I will write about noteworthy, informative, and provocative numbers and data. For example, few people know that the total amount of useable, renewable freshwater on the planet is a tiny fraction of all of the water on Earth. We see photos from space showing the vast surfaces of water in the oceans, ice caps, and great lakes of the world, but humans can mobilize and use only an insignificant portion of this. I might write about the current data on cholera illnesses and deaths and why those data are only part of the real story about water-related diseases. I will explore trends, uncertainties, and gaps in our collection and understanding of a wide range of environmental information on past and future climate conditions and impacts; water availability, use, and quality; food production; and the links between the production and use of energy and water.

Second, I will address confusions and challenges in understanding and reporting on science, misunderstandings or misrepresentations of science, and the complexities of interpreting science for policy makers and the public, including the issue of the use of “significant figures” in the classic mathematical and policy sense. For a perfect and humorous example of this, take a look at this comic from the genius of Randall Munroe.

For all we know, the odds are in our favor.
Thanks to and Randall Munroe, licensed under a Creative Commons Attribution-NonCommercial 2.5 License.

Look at the countdown clock in the cartoon. How many “significant figures” (in the mathematical sense) are there? We don’t know because the picture on the wall is hiding critical information: there might be four or there might be nine or more! The answer – and a strong understanding of scientific concepts – has consequences for humanity.

Third, I will occasionally highlight important and controversial people – historical and current figures in the public discussion over environmental issues. Some might be well known, such as John Muir or Theodore Roosevelt or Richard Nixon; some might (to many of us) be obscure, like Roger Revelle or Gilbert White or John Wesley Powell, but I think they will be all be interesting.

Sometimes I will highlight new research from the Pacific Institute or anywhere else in the world where innovative, provocative, and informative environmental science is happening. Sometimes I will explore a subject in the news that deserves more attention than traditional media might be offering, especially in these days of diminishing coverage of science (including environmental science) by newspapers, television, and radio.

A few minor ground rules: I encourage thoughtful comments and questions, even challenging and controversial ones, and will try hard to respond as appropriate. But I discourage – and will be strict about deleting – rude, ad hominem, and off-topic comments. I will be especially hard on marginal comments made by anonymous trolls. I encourage you to use your names, to ask questions, and to join a productive conversation.

Welcome to “Significant Figures.”


  1. […] Peter Gleick of the Pacific Institute joins, and here is his introductory post! […]

  2. #2 Greg Laden
    February 8, 2013


    • #3 Peter Gleick
      February 8, 2013

      Thank you, Greg. And thank you for your own wonderful posts here at ScienceBlogs! I’ve long enjoyed them.

  3. #4 bob brouse
    ottawa canada
    February 8, 2013

    Hey this should be fun, being from an environmental media
    anyone who puts forward well researched pieces deserves a cheer. from all of us at we hope your blog gets lots of traction and good luck!

    • #5 Peter Gleick
      February 8, 2013

      Thank you, Bob. And anyone interested in water in North America should be following you guys!

  4. #6 Steve Easterbrook
    February 8, 2013

    Peter – excellent choice of theme! I’m spending some time getting undergrads to think in terms of significant figures in both your first two senses – e.g. how to come up with first order approximations as answers to important questions (we spend some time on Fermi problems as an exercise). It’s a skill that seems to be lacking from much of our education system.

    • #7 Peter Gleick
      February 8, 2013

      Excellent! My experience is that 73.45832% of students don’t get this. Oh, wait…

  5. #8 Ethan
    February 8, 2013

    Glad to see you blogging here, Peter! Cheers!

    • #9 Peter Gleick
      February 8, 2013

      Thanks, Ethan. And thanks for your column!

  6. #10 José Sarukhán
    CONABIO, México
    February 8, 2013

    Look forward to your figures!!

  7. #11 Rob Taylor
    February 8, 2013

    Thanks for outing the AGW denier rent-boys at the Heritage Foundation, Peter. Its good to see scientists such as yourself and James Hansen taking direct action to raise public awareness on this vital issue – well done!

  8. #12 Brendan DeMelle
    February 8, 2013

    Fantastic news, Peter. I’ll check in often and alert the DeSmog audience to your new column.

  9. […] Peter Gleick of the Pacific Institute joins, and here is his introductory post! […]

  10. #14 Sagheer Aslam
    Montreal, Canada
    February 8, 2013

    Great start; I am working on sustainability of community-based drinking water systems, with a focus on developing countries. I can see that how useful this blog can be. The most important is that a person who have been working for last three decades on complex issues, especially related to water, is ready to share his views and answer the questions of inexperienced and novice individuals.
    I have one short question about the policy to share your articles posted here: Are we free to share it with friends through mails or social media? OR we have to ask for permission for any particular blog posting here?

    • #15 Peter Gleick
      February 8, 2013

      Thank you. Certainly you can share the link to the blog with friends and colleagues.

  11. #16 Ryan
    February 8, 2013

    Welcome! Looking forward to this blog.

  12. #17 Malcolm Croft
    February 8, 2013

    All the very best Peter.
    The issue of scarcity and use of renewable freshwater on the planet, is one that needs much public discussion. We here in NZ have a seemingly abundant supply, but all is not as it seems as I’m sure you well know. I, along with many others, am looking forward to your postings.

  13. #18 Hardy Cross
    February 9, 2013

    Re: Robert Taylor #11
    How did Peter “out…” the “deniers” (Heritage Foundation (what is a “rent boy?))? Have I missed something (the comment (#11 (too long to repeat)) sounds a bit snarky (is snark allowed?)) here?

    • #19 Peter Gleick
      February 9, 2013

      Hardy, yes, a bit snarky. I’m testing out the tone of the comments and tending, at the moment, to post most of them. I may get a bit stricter in the future. So, everyone, play nice. Snark is allowed, to some degree, but let’s try to be fact based and avoid the person-to-person ad hominem comments. Thanks.

  14. #20 Bud Ward
    White Stone, Va.
    February 9, 2013

    Peter: Very cool, and I look forward both to personally learning from your insights and also to sharing them, as appropriate, with the Yale Forum site I edit focusing on communications on science and policy issues related to climate change. Break a leg! (figuratively, that is)

    • #21 Peter Gleick
      February 9, 2013

      Bud, great to see you here. Happy to share posts and insights – the Yale Forum is a good one and I hope my readers will also visit it.

  15. #22 Nathan
    February 9, 2013

    Looking forward to reading your articles on National Geographic ScienceBlogs. Would like to see some work on groundwater and surface water interactions and integrated planning and management of the resource.

  16. #23 Rob Taylor
    February 9, 2013

    Oops, my apologies; I meant, of course, the Heartland Institute, a channel for fossil fuel industry funding of climate change denial.

    Which is not to excuse the Heritage Foundation for doing the same:

    • #24 Peter Gleick
      February 9, 2013

      Rob, I’ve allowed this post, but this probably won’t be the place for this kind of comment in the future. Let’s focus on the science.

  17. #25 Graham Symmonds
    Phoenix, AZ
    February 9, 2013

    I think this is going to be great, Peter. Understanding what the numbers mean is going to be a critical element for humanity to get a grip on real solutions. That’s particularly true when we are dealing with uncertainty. I look forward to your continued insight!

  18. #26 Shue Tuck Wong
    February 9, 2013

    Splendid idea! It is great that you care to spend your time in sharing your ideas in the science of sustainability sciences.

  19. #27 Russell Cook
    February 9, 2013

    Has commenter Rob Taylor at #18 already violated your guideline for “rude, ad hominem, and off-topic comments”?

    • #28 Peter Gleick
      February 9, 2013

      Could be. Since I’m just starting up, I’m feeling my way on the tone and nature of comments. At the moment, I’m trying to encourage feedback, but we’ll see moving forward. Thank you for your observation (which I’m also posting!).

  20. #29 Estella B Leopold
    Univ. WA, Seattle
    February 9, 2013

    Dear Peter, Glad you are doing this. I have been especially worried about the excessive use of beautiful clean water for fracking natural gas, and making those waters unusable. Given as you say only a small fraction of earth’s water is available to us, this seems like a huge problem, that is drawing little national attention. How can we get the administration, or perhaps the new Secretary of Interior, to pay real attention to this problem? At my brother’s cabin in Pinedale, Wyoming, the air is apparently getting really bad, which ruins the original beauty of the Green River Basin. We need some new “rules” about fracking and it’s impact.

    • #30 Peter Gleick
      February 9, 2013

      Estella, wonderful to hear from you. There will certainly be posts in the future about fracking and water issues. All the best, Peter

  21. #31 Elena Delavega
    Memphis, TN
    February 9, 2013

    Is there a way to get this blog sent to my email account every time you post something new? I looked but could not find anything.


    • #32 Peter Gleick
      February 9, 2013

      Elena, I think you can subscribe to the RSS feed on the right side of the column and get notifications of new posts; or just check back every few days!

  22. #33 doug lafollette
    madison, WI
    February 9, 2013

    Great. do I have to sign up to get this or ?
    I know of your work from Wil Burns

    • #34 Peter Gleick
      February 9, 2013

      I think you can sign up on the RSS feed on the right of the column and you should get the feed whenever I post something… Not sure, though!
      If not, just keep checking. Should be something every few days.

  23. #35 David J. Kent
    Science Traveler - Washington DC
    February 9, 2013

    Welcome, Peter. I’ve enjoyed your insights on HuffPost and Forbes, and I look forward to reading this column regularly.

  24. #37 Sagheer Aslam
    Montreal, Canada
    February 9, 2013

    Significant Figures : A Pacific Institute Research Report (Gleick, 2002), dealing with water related issues and diseases presented a figure of about 135 million deaths due to water related diseases by 2020 (if the situation of that time continued to exist) and even if the explicit Millennium Development Goals (MDGs) of the United Nations are achieved, a risk of 34 to 76 million deaths by the year 2020 was estimated.
    My question is: What is your present estimate if you review these numbers after a decade in 2012/2013?

    • #38 Peter Gleick
      February 12, 2013

      Great question. That assessment is in need of updating and revising based on the time that has passed, and on new data. Unfortunately, I think the news is still bad.

  25. #39 coby
    February 9, 2013

    Welcome to the Blorg, Peter! Look forward to your postings…

  26. #40 Susan Anderson
    February 10, 2013

    I would love to see some quick summaries of how bad ocean acidification is and how much dead zones are increasing over time. Ran into a stupid comment and wanted to reach for something that allowed me to be lazy and not look it up to refute the nonsense. Unfortunately, all fake skeptics have to do is make things up and turn them on their heads.

    Meanwhile, delighted to see you here.

  27. #41 Nicole Rosenleaf Ritter
    Bozeman, Montana
    February 11, 2013

    Very excited about this new venue for your work! I used to enjoy reading your work at SFGate. I hope you will consider a post about the role that science-based education can play in shaping attitudes about water. At the Project WET Foundation, we’ve found that children can actually be leaders in changing habits around water and other environmental issues. Cliche for sure, but children really are the future!

  28. #42 OPatrick
    February 11, 2013

    I look forward to reading your thoughts. Thank you for taking this step.

    Will you also be looking at what the numbers don’t tell us? There seems to be a danger of focusing too much on what we have good science on and not looking at areas of greater uncertainty which either haven’t been looked at in detail or can’t be looked at within a scientific framework. You do mention ‘uncertainties and gaps’ in your first area of focus, so I hope this won’t be a neglected area.

  29. #43 Dave Scott
    February 11, 2013

    James Hansen calls Keystone make or break, but I’m sure he reasonably assumes that once tens of billions are invested in moving tar sands to market, tar sands will be burned. I buy that argument. As McKibben also notes — and as you say here — averting climate catastrophe will require conscious decisions to do many, many things differently. Fighting Keystone matters.

  30. #44 Wayne Amacher
    Sunnyvale, CA
    February 11, 2013

    I am a retired engineer. All of the curves for global warming appear to be exponential. Exponential curves reach their knee when you can observe the effects. We are observing the anticipated effects now! Once past the knee of the curve we will not be able to stop global warming, except for whatever nature may decide to do. It’s, like running after a bus that is pulling away faster and faster (accelerating), and no matter what, you can never catch it.

    If we are indeed at the knee of the curve, shouldn’t we just give up and let nature take its course?

    (Of course, I believe in never giving up — but it’s still a good question.)

  31. #45 Steve (Paris)
    Paris, France
    February 12, 2013

    Is this a private fan club or can anyone join?

    • #46 Peter Gleick
      February 12, 2013

      Neither. It is a blog for discussion about complex issues. There are basic rules posted in my first post about the types of comments that will be rejected, but discussion, questions, appropriate on-topic comments (including disagreements) are certainly encouraged. Thanks.

  32. #47 Brad Phillips
    February 13, 2013

    #44 Wayne: You should read Nature Bats Last at Guy makes a convincing argument for the point you make in your comment. Peter, do you think Dr. McPherson makes the case for his prediction of Near Term Extinction of most species on Earth?

  33. #48 Maven (Chris Austin)
    February 14, 2013

    I’m definitely adding this one to my RSS reader!

  34. #49 Weizmann Science Writer
    February 26, 2013

    Welcome to ScienceBlogs. It’s a pleasure to be blogging alongside someone of your caliber, and I hope it proves to be a good medium for getting your message across.

  35. #51 Mark
    February 27, 2013

    Welcome to the network Peter. You might notice we have some topics in common over at the denialism blog.

    • #52 Peter Gleick
      February 27, 2013

      Thank you, Mark. I follow your pieces regularly and look forward to more interaction.

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