As WUWT readers may recall back in September of 2008, the New York Times ran an extensive first hand account of the Mohonk Lake, NY USHCN climate station of record. The Mohonk article was covered by WUWT guest contributors Dee Norris here and John Goetz here. Goetz shows that even the “pristine” station data gets adjusted by NASA GISS in their GISTEMP program.
NYT’s Anthony DePalma gave a very laudable account of the work done by the observers at the Mohonk Lake station:
Every day for the last 112 years, people have trekked up the same gray outcropping to dutifully record temperatures and weather conditions. In the process, they have compiled a remarkable data collection that has become a climatological treasure chest.
The problems that often haunt other weather records — the station is moved, buildings are constructed nearby or observers record data inconsistently — have not arisen here because so much of this place has been frozen in time. The weather has been taken in exactly the same place, in precisely the same way, by just a handful of the same dedicated people since Grover Cleveland was president.
DePalma also writes:
The record shows that on this ridge in the Shawangunk Mountains, about 20 miles south of the better-known Catskills, the average annual temperature has risen 2.7 degrees in 112 years. Of the top 10 warmest years in that time, 7 have come since 1990.
WUWT contributor Denise Norris looked into the temperature record at Mohonk and writes:
Here is what I found:
Since I live in the general area, I have previously used the data from a site in nearby Maryland, NY (42.52N, 74.97W; 363m) in a local lecture. I was sure I remembered that the station in Maryland had not exhibited a trend like this. Double checking the ol’grey matter, I got this graph:
Both sites are at the same altitude and in the same general vicinity. I know that climate change can’t be that localized, so it has to be something else.
I should point out that the graphs Denise posted above use the RAW unadjusted USHCN data, (from CO2science.org ) rather than the adjusted GISTEMP record so many are familiar with. In the GISTEMP record, Maryland, NY is shown to be nearly flat while Mohonk seems to be the same.
My experience and the experience of many others in surveying the USHCN network of climate monitoring stations has shown that time and again, when such a significant divergence is seen with two nearby stations, localized siting issues and other microsite biases are often found at the weather station. On January 4th and 5th, 2009, WUWT contributor Evan Jones set out to find the answer. Due to other projects that required my attention, it has taken me until now to find the time to write this article.
First and foremost I should point out that I do not disagree with the NYT’s characterization of this station as being valuable due to its lack of station moves and long and meticulously recorded record of temperature and precipitation. The staff at Mohonk should be commended for their long and dedicated service. It is not my desire to impugn that in any way. However, it should be noted that what Evan Jones found at Mohonk mirrors some of the slipshod quality control that is under the purview of NOAA as the entity responsible for the equipment at COOP and USHCN stations around the USA. The responsibility for the quality control failures that I am about to highlight lie solely with NOAA, and not with the staff of Mohonk. It is NOAA’s responsibility to ensure that these stations adhere to specifications and to perform regular quality control checks.First some perspective as to where the Cotton Region Shelter (Stevenson Screen) and the Standard Rain Gauge are located on the grounds. Evan provided this annotated map:
The station’s Cotton Region Shelter (CRS) is located on the public grounds, just a few feet off of a public path. On first approach, a couple of obvious problems appear right away.
Upon closer inspection we see the CRS is directly next to a tree stump.
And, the CRS is rather close to a building and chimney.
Looking at the photograph, here’s a few questions that come to mind. The CRS is located just a few feet from a building with an active chimney. The building is L shaped, and thus acts as a wind block for at least two directions. If the building was there 100 years ago was the chimney there then? When was central heating and A/C added? How much of the waste heat of the building is imparted to the thermometers by prevailing winds? Evan Jones reports in his site survey (PDF) that the “CRS is 5.8 m. from building to South”. That would make it a class4 station (considered as unacceptable siting) by the current criteria used to evaluate siting (PDF) for the NOAA Climate Reference Network. It also violates NOAA’s longstanding 100 foot and distance to 4 times height rules as documented in the NOAA/NWS COOP Observers Handbook (PDF available here) and on the COOP web page here.
The CRS also has brush around it, and most notably has a large tree stump directly adjacent to it. Obviously at one time, there was a significantly large tree there that was cut down. There is also a large tree limb missing from the tree to the right. The CRS thermometers obviously recorded temperatures in the shade of these tree canopies. Seems’ like a good idea right?
For those that don’t know, measuring temperature under a tree canopy at the base is one of the worst places to do so for a long term record. Here is why:
- The shade of the tree canopy will suppress the Tmax in the summer due to decreased solar insolation in the local area
- The lack of a shade canopy will enhance the Tmax in the winter due to increased solar insolation in the local area
- The shade of the tree canopy will elevate the Tmin in the summer, due to LW infrared being reflected back to the ground by the leaves, resulting in a localized warming.
- The lack of shade canopy will the lower the Tmin in winter due to increased LW infrared emissions (as compared to summer when the canopy reflects LWIR).
- The tree grows, and the effects grow with it over the long term. They don’t end until the tree is trimmed, dies, or is cut down.
- The growing tree trunk gradually blocks air flow at the rear of the screen and is a mild heat sink.
Then of course there’s the state of the bushes. Trimmed regularly, overgrown and then cutback? Were they always there? when was the tree trimmed?
It appears some recent trimming done, perhaps due to a storm taking down a branch:
Here’s another view:
Some of these problems associated with trees and placement (specific to the USHCN network) are documented in the paper published in March 2005 in the International Journal of Climatology titled: The GeoProfile metadata, exposure of instruments, and measurement bias in climatic record revisited by Rezaul Mahmood , Stuart A. Foster, David Logan. Abstract available here.
But wait, there’s more.
In this picture below, notice the base of the CRS, made of logs, possibly from the tree that was cut down. Other than the fact that shade from the building is hitting the CRS, notice anything peculiar?
There is a standard height that the CRS must be off the ground. In this case the homemade log legs are shorter than normal, and according to measurements made by Evan Jones, the base of the CRS is only 29 inches from the ground surface. Normally it would be 48 inches. You can read about the design criteria in this CRS manual (PDF) by a company, Novalynx, that supplies them. There is also a reference at NOAA here in FAQ#17 that states the wooden leg length to be 48″.
They write: The legs are designed according to the original criteria to give the shelter a height above the ground of 48 inches.
The lowering of the screen height will create a warm bias, and since it is likely that these were not always the legs for this shelter (which appears relatively new) there will be a slight step function upwards in the temperature record when this occurred. Why NOAA allowed this I have no idea.
Here’s another view of the legs and the ground underneath.
Other than the photos seen above, there is only one other publicly available photograph of the CRS at Mohonk Lake. I’ve shown it below. The present curator, Mr. Paul Huth is standing near the CRS preparing to open the door.
Source: http://www.mohonkpreserve.org/index.php?weatherdata
I had always wondered what the dark material under and around the CRS was. It appears to be mulch and/or wood chips. Certainly such a ground cover with a dark albedo is not a good thing near a weather station.
When Evan was there, there was snow cover. But he found the ground cover by the CRS to be a dark crushed rock, similar to “road base”, shown below.
He photographed it in his hotel room at the resort and returned it to the site.
Crushed rock is not a good surface cover near a weather station as it will absorb more solar radiation on sunny days, raising Tmax and the rock will radiate LWIR at night raising Tmin. How long has the crushed rock been there? Was it always that way, or was it grass or some other surface cover in the past? The crushed rock base certainly doesn’t fit the “representative of the area” specification for siting a Cotton Region Shelter in the NOAA/NWS COOP Observers Handbook (PDF available here).
3.1 Shelter Placement. The ground over which the shelter is located should be typical of the surrounding area. A level, open clearing is desirable so the thermometers are freely ventilated by the flow of air. Do not install on a steep slope or in a sheltered hollow unless it is typical of the area, or unless data from that type of topographic location is desired. When possible, the shelter should be no closer than four times the estimated height of any obstruction (tree, fence, building, etc.). Optimally it should be at least 100 feet from any paved or concrete surface. Under no circumstances should a shelter be placed on the roof of a building as this may result in extreme temperature biases.
In fact it appears that little about the Mohonk Lake USHCN station fits that criteria. If you look at the photograph that NOAA supplies with their handbook for section 3.1, the differences are obvious. Note the grass under the shelter and lack of nearby obstructions.
Finally we have the rain gauge, at the end of the public dock protruding into the lake. In such an open public area where fishing, swimming, boating, and picnic coolers abound, could it be assured that somebody didn’t pour their coke, coffee, or take a whiz in the gauge? Would the Mohonk staff catch it if somebody did, or would they just dutifully record the level on the dipstick, write it down, and empty the gauge into the lake?
Here is the closeup photo Evan took of the rain gauge at the end of the dock:
I found this photo taken by a tourist and placed on Flicker photo service:
And since there was a 10+ megapixel version of the photo available, I was able to isolate and identify the rain gauge using Evan’s photo as a guide.
Going back to NOAA’s COOP website I found this criteria for rain gauge siting:
Precipitation gauge siting: The exposure of a rain gauge is very important for obtaining accurate measurements. Gauges should not be located close to isolated obstructions such as trees and buildings, which may deflect precipitation due to erratic turbulence. To avoid wind and resulting turbulence problems, do not locate gauges in wide-open spaces or on elevated sites, such as the tops of buildings. The best site for a gauge is one in which it is protected in all directions, such as in an opening in a grove of trees. The height of the protection should not exceed twice its distance from the gauge. As a general rule, the windier the gauge location is, the greater the precipitation error will be.
Looking at the boats stacked there, it made me wonder how they might affect the rain gauge with wind turbulence. I did some additional digging and found this photo, also from a tourist on another photo sharing site called Webshots.
I wonder what the boats stacked around the rain gauge does to the precipitation record?
Clearly the Mohonk station has a value in it’s long and uninterrupted record. But it pains me to say this, as I always feel bad for the observers when NOAA doesn’t step up and help them with quality control, but the value of the Mohonk Lake record has been tarnished due to the significant number of local site issues related to placement and maintenance of the thermometer and the rain gauge. When you look closely with NOAA’s own criteria (something the NYT reporter didn’t do) you find that the station isn’t as good as the story leads us to believe. Even NOAA’s spokesman quoted in the article made no mention of these issues:
“The quality of their observations is second to none on a number of counts,” said Raymond G. O’Keefe, a meteorologist at the National Weather Service office in Albany. “They’re very precise, they keep great records and they’ve done it for a very long time.”
But I wonder, has Mr. O’Keefe ever visited the station, or is he just assuming the data quality is there because the Mohonk staff does such a good job with the monthly B91 form they send in? I agree, they do a great job of record keeping. For example here’s the December 2008 B91 form completely filled out and with extra detail.
mohonk_lake_b91 (PDF) Source: NCDC http://www7.ncdc.noaa.gov/IPS/coop/coop.html
December is normally a problem month for records, yet to their credit, they have every day.
But even with such attention to detail in record keeping, how valuable is such a record when there appears to be no attention to detail in the exposure and placement of the instruments gathering the data?
When scientists look for the “global warming signal” of a few tenths of degrees, how would they know if the data they are getting is accurate if they don’t know the provenance of the station quality? Even if they did know the things we know now about Mohonk Lake, how would they go about sorting out the local site biases that have cropped up over time and apply a correction?
Then there’s the resort itself. The NYT article claims it “has hardly changed over time”.
“Mohonk’s data stands apart from that of most other cooperative weather observers in other respects as well. The station has never been moved, and the resort, along with the area immediately surrounding the box, has hardly changed over time.”
Yet if we were to examine things like: when was air conditioning installed for guest rooms? When were the grounds walkways and pathways switched from dirt or stone paths to concrete or asphalt? How much has bus and automobile traffic increased in the last 100 years? How many additional outbuildings have been built? How much of the ground cover, trees, shrubbery, and landscaping has changed? I wonder by what basis the NYT reported made that sentence? Given how much energy is used for heating/cooling cooking, laundry, landscaping and trasnportation, surely the resort has it’s own localized UHI signature compared to surrounding areas.
A tourist resort is hardly a static place. They are always being revised and improved to keep the customer experience fresh and rewarding, so I have a little trouble believing that Mohonk Lake “has hardly changed over time”, especially since the NYT reporter missed everything else about the station’s measurement environment.
I feel for the staff at Mohonk, and I have contempt for NOAA and the NWS for allowing this station to escape basic quality control.
Sylvia:
Yes, we favor the observers. They are a delightful lot (I have personally interviewed around a hundred of them), civic minded, patriotic, public spirited volunteers.
Either they trudge through the snow or put up with the NOAA trenching up their lawns and drilling holes in their houses.
The most common spontaneous answer when I thanked them for their service was that it was FUN. And many of them had their kids involved. A curator’s wife said her husband refused to go on vacation unless he could find someone to cover the readings for him.
One thing that astounded me. NOT ONE IN FIFTY OBSERVERS KNOW THEY ARE PART OF THE USHCN. I interviewed an NWS station the other day. The observer said, “Huh? We are HCN? Didn’t know that.” She knew what HCN was–and didn’t know her station was a part of it!
Well, over 10% know now–because I told them. They were universally impressed by the information. They had no idea they were in charge of the most important weather stations in the world! One of them told me, “Well, I’ll never miss a day of data after this.” Another one told me, “I was think of giving it up. But this inspires me.”
No I did NOT tell them there may be problems with their stations’ data! Because it is important data even with its problems, and we MAY somehow figure a way to factor most of the error out.
Why the NOAA does not inform its HCN observers of the fact that they ARE HCN is beyond my ken.
I spent a good deal of time thumbing through the library of congress historic photos of the place around the time of the original article published here. Unfortunately, I had no idea where the shelter was located at the time, so my search for comparisons between then and now amounted to nothing more than searching grainy black and white photos. Someone who has actually been there would probably have better luck.
All in all, Mohonk Lake is probably one of the most photographed areas near a weather station I’ve found. Including a relatively high resolution set of areal photos from the U.S.G.S. if anyone is interested in looking at changes over time to the area.
Bill Schulte (19:43:28):
Actually that’s not a bad idea. Since there is a weather station right next to the tree, one could calibrate tree ring readings to temperature and rainfall. As we all know, tree rings are used as proxies in some… ahem… well known “climate” work. I bet it would throw a damper on the alleged accuracy of these proxies.
Of course, the bristlecone pine is especially useful for making hockey sticks…
I imagine that the station was removed to cut down the tree,it is too close to risk damage. An image of the location before tree removal would be useful.To me it looks as if were cut 10-15yrs ago.
I bet that would sell well at the Heartland Conference next year — Hockey sticks made from bristlecone pine.
how about setting up a screen that meets the standards a short distance away then comparing the results over a period, could prove quite an embarresment for NOAA & NWS. Organise volunteers to do this at “contaminated sites” at various locations.
Anthony–
Great work, as usual. I read the NYT article when it was published and wondered if there was another side to the story. Turns out that there is. Did you contact the article’s author for a response?
REPLY: Not yet, I figured I’d wait for a bit of net peer review first. -A
D. C. (19:45:46) :
I think your knowledge would be very useful in trying to capture the long-term history of this station. That addresses one of the early criticisms of the surfacestations project insofar as not being able to document the sites as they changed over time. So every bit of history is useful, imo.
The evergreen Rhododendron surrounding the screen must have been planted there at some time. Maybe the leaves internal 21.4 C provides a micro climate, cut them down and there will be a climate change?
http://wattsupwiththat.com/2008/06/13/surprise-leaves-maintain-temperature-new-findings-may-put-dendroclimatology-as-metric-of-past-temperature-into-question/
This episode illustrates the classic pattern. The front-line workers (observers) know their equipment and are highly dedicated to performing their jobs well. Their supervisors (NOAA managers) are negligent in the maintenance of the equipment and just keep pumping out the same low-quality item because there’s no competition. Marketers (the press) advance a story line rather than telling the truth about the product. Whistleblowers (WUWT) are accused of being mere troublemakers with nefarious designs and shady associations. Purchasers of the product (the public) who rely on it’s quality are kept in the dark while those profiting from it (climate scientists and politicians) work hard to keep the cover-up in place.
Treerings from the stump should indicate when it was cut, to within a few years. It might even be possible to treering-date the rustic log base.
REPLY: Its easier to just call and ask. – Anthony
Eric:
The US is only a small percentage of the earth’s land area anyway, and if were are interested primarily in data on global climate change, is it worthwhile for NOAA to invest a lot of money in improving sites in the US, or are there better uses for US government dollars by NOAA.?
Short answer: no, there are no “better uses” for dollars given to NOAA, because NOAA is supposed to be doing what’s called “Science”, and drastic measures are currently being proposed and enacted to “save Humanity, etc.” – which instead will quite probably end up harming Humanity, etc. – based upon NOAA’s, et al., brand of “Climate Science” – starting with the concept of Global Temperatures, which NOAA is obviously not handling scientifically here in the U.S.
How can “scientists” particularly interested in global temperatures not have checked even one of their thermometers to see if they were working correctly and still be said to be doing science?
Therefore, how can we believe anything these “scientists” say about anything, that is, until NOAA, et al., fix their temperature recording units/sites and then procede truely scientifically from there?
And if the U.S. is not measuring temperatures correctly for the purposes of determining “global climate change”, what about the rest of the World?
Eric, not only is the science of “climate change” not settled, it’s hardly even begun.
OT . Anthony, a while back you reported the instigation of a weather station survey in UK. Is there anything to report on that so far? I would be willing to volunteer to help if someone could let me know who to contact.
David Jones
REPLY: Something happened with that group, they closed up their website. Not sure why. Perhaps photographs of airports (and weather stations there) got the security folks in a tizzy. – Anthony
It would be nice to see mainstream media pick up these types of stories. I look forward to reading the final report once surveying of all stations is complete.
Fascinating. Goes to show that nothing is “frozen in time”. All those trees were just wee little saplings at one time, and nothing at all before that. Forests always moderate the climate below their canopy. Unfortunately the Mohonk station looks like it was gradually swallowed up by a small forest….
Well if anybody had turned in a set of experimental data such as either of those two graphs, and added those straight red lines as being smoothed versions of that data; in any Physics lab that I taught; they would get a failing grade.
Assuming that the original thermometers read accurately; which I agree is an unjustified wild assumption on my part; those blue line graphs show variability; because the data they were reporting (a temperature I assume) was varying over that time frame. So all the bumps and squeaks in those graphs are presumably real values from an actual physical system.
By what mental prestidigitation did they conclude that the function that was being represented, is in fact a monotonically linear with time function that can be represented by a straight line.
There’s probably so theorem of statistical mathematics that says that is the straight line the best represents the raw data set (and presumably ignores ALL data either before, or after, the first and last data points in the set.
Just because a particular mathematicsl discipline says that is the best straight line; doesn’t mean their is any physical reality to that straight line; and it adds precisely zero additional information to the original blue graph data set.
If this is what passes for climatology; we are all in deep trouble.
I look forward to reading the final report once surveying of all stations is complete.
We’ll never get them all.
c. 100 are closed.
And NOAA pulled the names of the curators from their site, and we are missing 50 to 100 contacts. On a rare occasion we can nail these from physical location using Google earth and get them from Google Street Level. But those are hard to find even by car, if one doesn’t know who the curator is and has no address.
So without direct NOAA cooperation (not forthcoming), we will never hit 100%. But we are at over 75% and can probably push it a bit more.
Apart from the obvious problems with the historical temperature data that this post, and others, exposes the other point is that the NYT article is an utter fabrication.
I mean it’s a total out and out lie. The only thing I can determine for sure from it is that Anthony DePalma has never actually been to Mohonk Lake.
I wouldn’t go that far. I don’t think the author was equipped with the knowledge to distinguish good station siting from bad, and was instead fixated on the lack of station moves.
I don’t think they’re lying, I think the just don’t get it (and may not want to).
It is thrilling to see my community caught up in the global warming debate. I live a few miles from Mohonk and have hiked and climbed there over a thousand times in the past 30 years. The Mohonk area is a natural gem less then 100 miles from Manhattan. I would recommend it to all nature lovers. The best times of year to visit are in late May to early June when the Mountain Laurel blossoms turn the mountain white with an overwhelming perfume sweetness. Also the standard October psychedelic leaf viewing season. Mohonk has the finest rock climbing in eastern North America.
Also of note the 1994 movie “The Road to Wellville” was filmed at Mohonk. The Mountain House was depicted as the sanitorium of Dr. Kellogg of cereal fame. A very enjoyable film that mocks the natural health movement from the turn of the last century.
Everyone should visit Mohonk to get a dose of the best of nature in eastern North America. The manicured gardens at the Mountain House are spectacular. Unfortunately mountain biking was sharply curtailed 20 years ago due to yahoo bikers injuring hikers. The view from the top of Smiley tower is spectacular. Six states can be seen. It is rumored that it is the inspiration for Bob Dylan’s All Along the Watchtower song. Dylan being a resident of the area in the mid 60’s.
NWS used to have Coop Program Mgrs that were primarily responsible for maintaining these types of stations. Alas, these people have gone the way of 45 rpm records. As a retired NWS employee, I can tell you that Mohonk HCN site problems are typical of many (most?) Coop sites in use today. The model of assiduous observers dutifully logging GI so NOAA can get GO is also very typical. On a happier note, NCDC’s Climate Research Network (CRN) has been very carefully sited and may provide ground truth for HCN places in the future.
And thanks for a very informative article eliciting savvy comments.
One would need to show that a “global anomaly” has any validity in the first place. Measuring temperatures in one place and comparing those measurements against temperatures in a totally unrelated place means nothing, especially when one place is warming and one is cooling.
Well, this is interesting. Having a closer look at the photos in this article, it appears the shelter is much closer to the lake than I had originally thought.
Looking at the first photo (northeast from road) we have a green roof with cupolas. That becomes clearer with the third photo showing the overall view with the building and chimney. The fifth photo (west by northwest) shows the main hotel building in the background. Matching the line of the roof of the main building, we are directly across the grassy section of the gardens at the boat dock.
Moving on to the panoramic view used to pinpoint the rain gage, if you look at the far left background you find a narrow building with a cupola on the roof. The shelter should be just out of frame beside that building.
Moving on to expand the search, now that I know the location on the grounds relative to the main building, have a look at this photo from the library of congress… Ah, I forgot I can’t link directly to the photo, however follow the link to the search page, enter Mohonk Lake. It will be the first link titled “ Mohonk Peace Conference, Mohonk Lake, N.Y. Circa 1915.”
http://lcweb2.loc.gov/pp/pphome.html
The archive version of that photo is 6 meg, and if you look to the far right you see the hotel building, the center would be roughly in line with the docks, and the upper left background we have a narrow outbuilding with a single cupola in the center and no “L” shaped extension off the end.
I have zoomed, panned, lightened, darkened, inverted, sharpened till my eyes crossed. Sometimes I can almost see the squareish outline of what may be a CRS shelter next to the building, but honestly, I have seen clearer pictures of bigfoot or the grassy knoll. If the shelter is where it has always been, it has never been properly sighted since 1915 anyway.
Moving on to what has become my favorite aerial photographer’s website, I introduce you to Flyin Phils Photos. Now, Phil has 2 sets of photos from Mohonk Lake, one dated 1998 (0027, 0028, 0029) and one set from 2006 (0071, 0072, 0073, 0074, 0075).
http://www.flyinphilsphotos.com/photo-info/psw.html
If you take a look at 0072 (which leads to rsz_71.jpg) you will find the green roofed, L shaped building with 3 cupolas directly across from the main hotel building, just to the left center of the picture. Zoom in a bit, searching through the leafless tree in front of the building and you can just make out a squareish white shape beside the building. Also visible in the next photo, (0073 leading to rsz_72.jpg) just in frame on the left side.
In any event I’ve taken this as far as I can for tonight. Other than a couple new buildings and a parking lot uphill… and some new siding on the building.. Vertical plank from the picture of Paul Huth to standard lap siding in the current photos.. plus a tree gone mia sometime before 1998 I don’t have much to contribute. Still have a lot of archive photographs to sift through in my spare time. Maybe something else will pop up.
Oh, I apologize for leaving so many links to fish through rather than simply hosting the images with notations attached. Just not enough time in the day.
Someone might enjoy comparing the tree rings against the record from the overly adjoining thermometer.
On a happier note, NCDC’s Climate Research Network (CRN) has been very carefully sited and may provide ground truth for HCN places in the future.
Yeah, what about CRN? Those are supposed to be great sites. (Assuming we don’t have an HO83 issue.) All data to be served raw. All sites photoed, too, though I never saw them.
I started to pursue that with NCDC, but the trail dried up. I understand they got about 80 of them up and running but then the whole thing sort of went away. (I read somewhere they had abandoned it because of satellite readings.)