Collaborative using UVM researcher using NSF grant to recreate regional temperature data

Discovering a missing piece of recent climate data

University of Vermont

L-R: rant Harley is assistant professor of geography at the University of Idaho. Justin Maxwell is associate professor of geography at Indiana University. Rayback is associate professor of geography at UVM. Credit: University of Vermont

L-R: Grant Harley is assistant professor of geography at the University of Idaho. Justin Maxwell is associate professor of geography at Indiana University. Rayback is associate professor of geography at UVM. Credit: University of Vermont

Schoolchildren know that the age of a tree can be measured by counting the number of rings in a stump. But rings in especially old trees contain data that can’t be measured so easily. For example, stands of old growth forest contain centuries worth of temperature data that can be a key to completing the picture of how the climate has changed over the past several centuries.

Shelly Rayback of UVM’s geography department, and two colleagues, Grant Harley of the University of Idaho and Justin Maxwell of Indiana University, are using a $360,000 National Science Foundation grant to unlock this data and reconstruct summer air temperature in the Eastern United States.

“Our colleagues have been able to reconstruct moisture availability in this region, but no one has been able to reconstruct temperature on a large scale across the eastern United States,” Rayback says. “This has been a thorn in our side, because while we have fairly dependable temperature data recorded over the past 120 years or so, we don’t have a clear picture of what the temperature has been like over the past 300-500 years.”

The team of researchers will use blue light intensity methods applied to tree ring samples of several temperature-sensitive tree species from North Carolina to maritime Eastern Canada, like the red spruce. A simple flatbed scanner can extract the blue light data to create a deeper paleolithic temperature record.

“We know average temperatures are rising, but what we’re trying to answer, in a longer-term context is, are the temperatures we’re experiencing today somewhat higher than the past, or a lot higher than the past? We’re guessing the latter is true, but we need the data to support that hypothesis.”

Rayback says the data will be relevant not only to understanding temperature trends in the Northeast, but can also contribute to our understanding of broader climatic trends in the Northern Hemisphere. The data could also contribute to developing better general circulation models (GCMS) that scientists use to predict climate in the future.

Grant Harley is assistant professor of geography at the University of Idaho. Justin Maxwell is associate professor of geography at Indiana University. Rayback is associate professor of geography at UVM.

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From EurekAlert!

86 thoughts on “Collaborative using UVM researcher using NSF grant to recreate regional temperature data

  1. “We know average temperatures are rising, but what we’re trying to answer, in a longer-term context is, are the temperatures we’re experiencing today somewhat higher than the past, or a lot higher than the past? We’re guessing the latter is true, but we need the data to support that hypothesis.”

    Is there no other options to explore? Perhaps today’s temperatures are somewhat cooler than at some time in the past? Looks like they’re trying to prove only that it’s warmer now.

    • As there are no 800 year old trees on the eastern seaboard, they will only be able to get back to the heart of the little ice age at best, thus they will be able to conflate natural rebound from the entirely natural little ice age with scary “global warming” and apply for future grants with gusto.

      • I would think that given the premise that there are no reconstructions for that region (which happens to be where I live) I would expect the researchers to be open to whatever the outcome is, thus including the possibility that it was warmer 500 years ago. Of course, I’m not a climate researcher, so what do I know.

        • They are presupposing the conclusion, when they should first be simply asserting an ability to extract accurate temperature info from tree rings.
          It is not like using tree rings for moisture reconstructions in the desert SW.
          In arid locations, moisture is limiting factor, so wider rings/faster growth correlates with more rainfall.
          But in a moist environment like in the East, there are numerous factors that can affect how fast a tree grows in each season.
          Every year has a two part ring, spring wood and summer wood.
          Trees can respond to numerous factors in complex ways.
          A Spring may be cool and wet, or cool and dry, but it can also have warmer nights and cooler afternoons. Or it can have large swings in temp, like far above and then far below average temps, or whatever. One season can have numerous excursions in moisture and temperature regimes.
          Insects or fungal diseases could wax and wane in the effect on growth over multi year periods.
          First lets see some proof that they can extract a valid temperature signal.

          After all, even with thermometers, just giving an average monthly or even daily temperature can be highly misleading.
          Warmistas pretend that warming over time means more extremes of heat.
          They also believe that what actually changes is “climate”, which means anything or nothing depending on what they want to write or be alarmed about this week.
          Is an increase in moisture due to a few floods but otherwise dry, along with unseasonable late spring or early fall freezes and frosts and terrible heat waves…or gentle rains evenly spaced about every three to five days, with plentiful mild sunshine in between and a gradually shift from one season to the next on a very regular schedule from year to year?

          One can have the same average temp or average rainfall with wildly different conditions.
          Many kinds of trees love it when it is evenly moist with highs around 82 and lows around 62, and hate it when it is very dry with highs around 102 and lows around 82, but then cooling off and getting very wet for an equal period of time with highs around 62 and lows around 42.
          Both have the same over all precip, and average overall mean temp around 72.
          I do not believe it is possible to collect reliable temperature data from tree rings, and even if it is I do not trust warmistas to do intellectually honest work.

          They claim we are in a crisis now, and it is beyond question…while those of us paying attention know they are just making it all up via alarmism, endlessly changing historical records, and fanciful models with little or no predictive ability.

          • This should be:
            “They are presupposing the conclusion, when they should first be simply ascertaining an ability to…”

          • Interesting Photo Caption L-R
            White Man … First and Last Name
            White Man … First and Last Name
            White Woman … Last Name Only

      • In Europe, dendrochronology has used overlapping sections of trees that grew centuries and millennia ago to construct a sequential chronology. They could do this on the East Coast.

        Jan

        • Dendrochronology is well supported, but gives dates. Getting temperature from tree rings is much harder since growth is determined by many factors, some of which play a larger role than temperature. Tree rings turn out to be imprecise thermometers.

          • But imprecise is OK because if we average enough values we can get precision measurements to 0.01 deg C! NOT!!

      • There are some cedars in Ontario claimed to be around 2000 years old…at Rattlesnake point. I wonder if the same goes in the Eastern US of A

    • “We are guessing the latter is true”, so that filter will influence how we read the data, though we will be so focussed we won’t realize the bias.

    • They don’t have any past temperatures, but when they do get them they expect them to be a lot colder than today’s. They then go on to say they need the data to prove that. Scientific method, where have you gone?

      Trouble is, they will get the result they want, because temperatures really were a lot colder thanks to the unexplained Little Ice Age. (Demonstrated in history by crop failures but unexplained in the “climate” models). And so these appalling grant-seekers go round and round in small destructive circles, wasting other people’s money and – if no-one can stop them – wrecking other people’s lives.

  2. Looking at temperature over the last 300-500 years keeps it within the Little Ice Age period. Expecting to find colder temperatures than currently is what they expect to find – as one would within the LIA.

    • The premise is false – width of tree rings depends on many things. You can deduce temperature from them only in special cases. For a counter-example, take the oldest known trees, bristlecone pines. They only grow for about six weeks in the spring, when snow thaws, and before it gets too dry and hot.

      For another word of caution, Mann’s “tree rings” temperature actually falls in the last decades.

      • Agree totally, far too many variables other than temperature determine tree growth rate. Not possible to get temperature from tree rings – as you rightly say that was something that Mann found out before finding a ‘trick’ to overcome his fundamental problem.

        • Yes, I just said the same thing as O.E. and Curious Geroge in another comment.
          In the arid desert SW of the US, rainfall is mostly in the cool season and precip in that part of the year is the main factor in annual growth.
          In the East, there is a complex interplay between moisture and temp, overnight temps, daytime temp, how evenly the rain falls, and unseasonable heat or cold spells.
          Let us see overwhelming proof…in other words scientific validation, or the whole premise it is possible to do what they say.
          Then let us see what the data says and draw what conclusions we may from that.
          They are presupposing not one but several dubious propositions before they even begin to do a single thing…except collect money from taxpayers. Nothing dubious about that…they have their hand out, promise the correct conclusion, and so get the money no questions asked.

          • Premise? I got your premise right heah! $360,000.

            But do have a care guys not to use that largesse to unveil ‘the little ice age’ that’s not s’posed to exist along that dead flat portion of Mann’s ‘hockey stick’ over preceding centuries before the more recent CO2 driven soaring to unprecedented heat/heights. That’s a really big NO NO.

  3. “We know average temperatures are rising, but what we’re trying to answer, in a longer-term context is, are the temperatures we’re experiencing today somewhat higher than the past, or a lot higher than the past?”j

    Hmm… what about the possibility our current temperatures are LOWER than the past?

    • The past that they are looking at is the Little Ice Age. Thankfully, temperatures are warmer than then.

    • I look forward to reading about how *ahem* “certain” tree rings needed to be removed from the sample set … due to anomalies with respect to data trend. Inotherwords … “certain” tree rings were not giving the answers as predicted, so they needed to be burned (to keep the “scientists” warm).

  4. Seems they know the answer in advance and just need to dig up some data so support the agreed answer

  5. Let’s see if they can figure out that trees not only stop growing when it’s too cold….they stop when it’s too hot

  6. “blue light intensity methods applied to tree ring samples” — wha?

    Googling…
    Well, it’s apparently a real thing, in the dendroclimatology community. They attempt to deduce climate information from the color variations of extracts taken from of the rings.

    One of the abstracts begins, “Blue intensity (BI) has the potential to provide information on past summer temperatures of a similar quality to maximum latewood density (MXD)…”

    That doesn’t sound like a ringing endorsement to me. But maybe by dendroclimatological standards it is.

    • “potential information” ? What does that look like. Maybe it needs to be homogenised before it can be used.

      This study looks like a crock before it even starts, but heck, if you can get $360k to fell a few trees and slap it in your scanner, why not. Nice gig if you can get it.

  7. I got as far as “For example, stands of old growth forest contain centuries worth of temperature data” and switched off with a yawn. No other factors affect tree ring growth, it seems.
    Then I thought, “oh well, may as well read the rest in case it gets any better”. I got to ““We know average temperatures are rising, but what we’re trying to answer, in a longer-term context is, are the temperatures we’re experiencing today somewhat higher than the past, or a lot higher than the past? We’re guessing the latter is true” Oh dear! Only two possibilities and both excluding the possibility of temperatures even staying the same, leave alone falling. Furthermore, a clearly stated incentive to find data to support the preferred hypothesis.
    What a waste of time. Do they get paid for this?

    • Yes 360000 smackers so they’re calling on lumberjacks everywhere to stick their tree samples on the scanner and count them and upload the results into the online computer model. Don’t worry the output will be presented personally at the next COP kneesup with appropriate media release beforehand and it will be worse than you thought.

      • With a bit of luck observa the Glasgow jamboree will be cancelled by coronavirus and the statements along the lines of “we have to save the planet at this conference, we can’t waste another minute” will just have to wait another year.
        Every cloud has a silver lining…

        • Now that really would be result!
          I had originally hoped that Scotland would declare independence before the jamboree so that English tax payers wouldn’t be saddled with it and Bon is could concentrate on things that matter like trade deals.

      • I hope that they will take core samples with a boring tool. It would be a crying shame to cut down 800-1000 year old trees for a climate study.

        I grew up in Charleston SC only a short distance from the Angel Oak. It is awe inspiring to consider that this tree was already over 1000 years old when the first colonists landed in Charleston in 1670.

  8. “We know average temperatures are rising, but what we’re trying to answer, in a longer-term context is, are the temperatures we’re experiencing today somewhat higher than the past, or a lot higher than the past? We’re guessing the latter is true”

    A proper answer to that questions by a scientist is “We don’t know.”

  9. It will be fascinating to see how they control for the spread of earthworms and humans over this exact period.

  10. All of you previous commenters have missed a key point. If their hypothesis proves true, they will in fact be proving that significant global warming occurs WITHOUT a related linkage to increasing CO2 levels, as the era they are exploring is before the widespread adoption of fossil fuels at today’s scale. Thus they will be proving that atmospheric CO2 concentrations are not necessarily the dominant factor behind the climate change (such as it is) that we are experiencing today. Ipso facto perhaps anthropogenic contributions are not nearly as significant as the alarmist’s want everyone to think.

    My 2 cents anyway.

    • Indeed. They have to be very careful. Dr. Michael Mann got it right. The temperature was constant until humans started using fossil fuels in a big way. If these guys get anything other than a hockey stick, they will be undermining the narrative. In that case, the SJWs will try to make sure they can’t even get a job as a garbage collector, ever, anywhere, for as long as they live.

  11. From the article: “This has been a thorn in our side, because while we have fairly dependable temperature data recorded over the past 120 years or so, we don’t have a clear picture of what the temperature has been like over the past 300-500 years.”

    All we need is the past 120 years of temperature data. That data shows it was just as warm in the 1930’s as it is today, and that means that CO2 is not an issue today because it wasn’t an issue in the 1930’s, so CO2 is not a problem and CAGW (Catastrophic Anthropogenic Global Warming) is dead as a result.

    Whatever warmed things up in the 1930’s (Mother Nature) could be the same thing warming things up today. The IPCC says CO2 was not a significant factor in the 1930’s warming, so CO2 does not have to be a significant factor in today’s warming, either, because both warmings are of equal magnitude and reached similar high temperautures. In the United States, it was actually warmer in the 1930’s, than today, by a lot. According to Hansen, 1934 was 0.5C warmer than 1998, and that makes it 0.4C warmer than 2016, the so-called “hottest year evah!”.

    The onus is on the alarmists to prove there is a difference between the 1930’s warmth and today’s warmth.

    But the alamist’s don’t argue about comparisons between the 1930’s and today, because admitting the 1930’s were as warm as today destroys their CAGW argument. instead they create false realities (Hockey Stick charts) where the 1930’s warmth disappears into insigificance, and then they don’t have to explain the 1930’s warmth away. Convenient for them, isn’t it.

    But the alarmists didn’t erase the actual temperature records, they just used computers to change the temperature profile, and then claim they know the temperatures better than the people who actually wrote the temperatures down on paper. But we can see how it was changed to conform to the CAGW fearmongering about CO2. Their bastardization of the temperature record is obvious.

    The Data Manipulators should be held accountable. They have inflicted untold harm on the human population of Earth with their lies and distortions of the truth.

    • Look at the pictures of the people doing this study.
      They appear to be of an age that makes it assuredly the case that they have never had anyone they do not condemn as a “denier’ voice a single skeptical word regarding their presuppositions and preordained conclusions.
      IOW…kids will now confirm the propaganda they have been force few their entire lives.
      Does anyone have any doubt what they will find?
      They do not seem to.
      Their mutual admiration society cheerleading squad has none.
      And no one in the community of the skeptical has any at all, either.
      So why even bother?

  12. Tree ring growth is more dependent on rainfall than temperature. Ask any arborist. Pond bottom pollen is subject to even more variation. There is a bias to “cold location ring samples” where tree trunks are preserved, over warm areas where old trunks rot away, also recent samples over ancient samples, because only “location lucky” trees actually get old. We only “sorta know” these proxy temperatures within a 3 degree C range, not good enough to determine whether a degree over a century, as we have experienced, is unusual or not. The divergence problem between Briffa and Mann data is notable in this regard. Basically one is led to the conclusion that tree ring temperature reconstructions are not very reliable, but very sciency-sounding.

    • I would say most vegetation responds to moisture changes rather than just temperature. That’s what my garden tells me. During last summer drought in Oz some bushes and smaller trees withered and died, even some gums, but as soon as the rains started every bit of vegetation exploded as if this was spring, with new shoots and obvious branch growth.

  13. I completed 30 years of atmospheric measurements on 4 Feb 2020. While processing these data will require considerable time. thus far I’ve not found any correlation of temperature with the clearly visible annual growth rings in branches of nearby baldcypress, hackberry and beau d’arc. The rings are slightly correlated with precipitation, but even these data are suspect due to the influence of shade from overhead branches.

    • Forrest
      I’m curious why you chose the particular tree species that you did. If I were doing a similar study, I would look for species that are 1) most sensitive to temperature changes, and 2) most sensitive to water availability. That is, species living on the ‘frontier’ of their climate zone adaptations. Thus, one might be able to tease out the differential effects of temperature and water from the growth-ring response of the different exemplar species.

    • These studies are typically done using the growth rings in the trunk of the tree.
      Branches have patterns which can vary for even more reasons that whole trees…including self shading, etc.
      That said, showing such a correlation, and determining how reliable it is, has to be done prior to doing some sort of long term study of how things have changed over long periods of time.

  14. The wonderful thing about tree rings is that they can be used either as thermometers or as rain gauges according to taste.

  15. When I was first instructed on how a research effort should be conducted – and a report written – the place to start was with a review of literature. I don’t see that effort here.
    There is much that has been written about using “treemometers” for reconstruction of past climate – none of it good.
    What a waste of money, time, and educated folk’s brains.

    treemometers
    Jeff Id, I think, but if not, apology to he/she that coined this.

  16. From the UVM associate geography professor, Shelly Rayback, faculty page:

    Her current research focuses on reconstructing climate using stable carbon isotope ratio time series derived from both live trees found in old growth stands and logs salvaged from the bottom of lakes and bogs in New England…. Dr. Rayback also works with colleagues and graduate students in UVM’s Rubenstein School and the U.S. Forest Service to understand the remarkable growth surge of red spruce, changing forest productivity and the influence of pollution of forest health in the Northern Forest.

    But, but the forests are growing rapidly amid all this pollution!
    What could possibly be the cause? We must investigate!

    Also take a gander at some of the courses she teaches…

    https://www.uvm.edu/cas/geography/profiles/shelly-rayback

    • I get the distinct feeling that they are only looking for data to support their hypothesis though.

  17. I believe there are old growth individuals in most areas that once had ancient trees. For whatever reason (hollows, low branching, etc.) they were passed up by loggers.
    Nonetheless, I don’t know of ANY species that one could look at rings, and say, “That was from lack of water”, or “that was from lack of warmth”.
    I do know it is common to look at the growth rings of very old trees (in the Midwest USA that’s 300 plus) and see growth patterns. One that is very common, is to see the first 80-100 years with practically no growth at all. Then it “blossoms”. One always assumes that this is because the larger trees around it were blown up, blown down, or succumbed to some natural event.
    I have NEVER seen a competent arborist say they think it’s because the climate changed.
    I believe it’s fundamentally bad science from the git-go.

  18. [QUOTE FROM ARTICLE]”For example, stands of old growth forest contain centuries worth of temperature data that can be a key to completing the picture of how the climate has changed over the past several centuries.”

    Tree rings only contain data regarding the growth rate of the individual tree over past years, that doesn’t necessarily correlate only with temperature.

    It is possible that an unusually mild early spring and/or autumn may prolong the growing season enough to result in above-average annual growth and a wide tree ring for that year. But what about growth rates during the summer months (June to September) when there is no danger of frost, but growth rates depend more on availability of water (precipitation) than temperature?

    During a long period of summer drought, some trees will go dormant, to the extent of dropping some of their leaves in August after a dry summer, while the same trees would grow faster during a wet summer. In general, summer temperatures are higher in sunny weather than in rainy weather, so that a hot summer may actually have slower tree growth (if there is not enough precipitation) than a cooler, wet summer.

    A tree ring basically shows the total growth of the tree during the year, an integrated average of the growth rate between when the leaves emerge in spring and when they drop off in autumn. Above average temperatures in early spring or autumn may prolong the growing season, but may slow down the tree’s growth during the summer if not accompanied by enough precipitation, so that tree rings are not a proxy for temperature, but are an indicator of a mix of temperature and precipitation in unknown proportions.

    Tree rings of deciduous trees also do not indicate anything about winter temperatures, since such a tree remains dormant from late November through early March regardless of whether there are thaws or cold snaps during the winter.

    A detailed study of rings of old trees can answer the question: was the spring/summer/autumn climate of X years ago in this location favorable to the growth of this species of tree? It cannot make any conclusions about temperature.

  19. Another confirmation bias request for money to prove what we know. That is the fundamental problem that plagues politics and political science.

  20. Besides for my previous comment above, I am wondering about what data sets they will use to confirm or correlate temps over the past hundred to 140 years?
    Will they use the adjust records published for public consumption, or are they gonna use the original raw temperature data?
    If they do not like the story told by thermometers, they simply change what was written down over the years by the people reading the thermometers at the time and in the particular place in question.
    So now tree rings are thermometers?
    They do not even know how to be honest or stick to scientific methodology.

    • I think you expressed the answer in your questions and statements. They already know what the temperature history should be, so they will find and repair the data that shows the truth of which they are certain.

    • “Besides for my previous comment above, I am wondering about what data sets they will use to confirm or correlate temps over the past hundred to 140 years?
      Will they use the adjust records published for public consumption, or are they gonna use the original raw temperature data?”

      Either. the small differences between adjusted and raw on the east coast won’t change a reconstruction.

      if you like you can test this for yourself.

  21. Mickey Mann will be delighted that the “science” of dendrobfuscation has been picked up by the younger generation. No doubt he can train them how to extract the 365 and 1/4 days worth of hourly records of moisture, temperature, soil nutrients and sunlight that each ring contains to give an accurate average annual temperature.

  22. My understanding from data available from NOAA and elsewhere is that the planet was warmer than now for between 1000 and 5000 years of the Holocene interglacial

  23. I see they are geography students. So obviously well versed in statistics, atmospheric physic and meteorology

    • I would have thought that biology was the most relevent field is you want to interpret the temperature dependency of plant growth. What the heck has this to do with geology.

      I though the smallest unit of time for a geologist was 10ka.

      How did they get a grant to study something which is totally out of their field of study ?

  24. “We know average temperatures are rising, but what we’re trying to answer, in a longer-term context is, are the temperatures we’re experiencing today somewhat higher than the past, or a lot higher than the past? We’re guessing the latter is true, but we need the data to support that hypothesis.”

    As soon as you read that, you know that this is not a scientific study but just another paid-for propaganda exercise on behalf of Global Warming/Climate Change.

  25. What sort of organisation gives a bunch of geographers a $360,000 grant to research past temperatures using tree rings? Is it just me or is this not a long way outside the expertise required for such a study? How can they possibly make reasoned scientific conclusions on the data they gather? If I want someone to interpret an old map I might ask a geographer but to interpret data produced by complex biochemical reactions in old trees I might look to a say, a biochemist or a relevant field of study. Geography, really?

    Looks like anyone can get their snout in the funding trough, as long as you play the game i.e. say the right sorts of things to the right sort of people.

  26. ”are the temperatures we’re experiencing today somewhat higher than the past, or a lot higher than the past?”

    This has probably already been said but ….Ha ha ha ha ha! Oh….stop it now….enough…

  27. I thought that one problem with the hockey stick was that the most recent data from tree rings didn’t fit the required narrative, so actual thermometer figures for the latest years were spliced onto the tree ring temperature data.

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