By Steven Goddard and Anthony Watts
Fort Collins, Colorado is most famous for Balloon Boy, and Boulder, Colorado is most famous for Jon Benet and Ward Churchill.
Both are hotbeds of Climate Science, with familiar names like Roger Pielke (Jr. and Sr.) Walt Meier, William Gray, Kevin Trenberth and Mark Sereeze. Both are of similar size (Boulder 91,000 and Fort Collins 130,000) and located in very similar geographical environments along the Front Range – about 50 miles apart. The big difference is that Fort Collins has tripled in size over the last 40 years, and Boulder has grown much more slowly. Fort Collins population is shown in blue and Boulder in red below.
Sources:
http://en.wikipedia.org/wiki/Fort_Collins,_Colorado
http://en.wikipedia.org/wiki/Boulder,_Colorado
Until the mid-1960s, NCDC temperatures in the two cities tracked each other quite closely, as you can see below. Again, Fort Collins in blue, and Boulder in red – with Fort Collins temperatures shifted upwards by two degrees to normalize the left side of the graph. Since 1965, temperatures in Fort Collins have risen much more quickly than Boulder, paralleling the relative increase in population.
Source: NCDC Boulder Temperatures NCDC Fort Collins Temperatures
The graph below shows the absolute difference between Fort Collins temperatures and Boulder temperatures since 1930. There is some sort of discontinuity around 1940, but the UHI imprint is clearly visible in the Fort Collins record. The Colorado State Climatologist, Nolan Doesken manages the Fort Collins Weather station. He has told me that it has never moved or changed instrumentation. and that he believes the increase in temperature is due to UHI effects.
Roger Pielke Sr. further commented:
“the Fort Collins site did have the introduction of the CSU Transit Center a few years ago, although this is well after the upturn in temperature differences between Boulder and Fort Collins started to increase.”
From the promotional photo on the CSU website, the Fort Collins USHCN weather station (below) seems reasonably sited.
However when you look at the Google Earth street view, you realize that it is surrounded by concrete, asphalt, nearby parking, and a building just 7.5 meters away (By the GE ruler tool). It would rate a CRN4 by the surfacestations rating. It also appears to have been modified since the promo photo was taken as there is a new fence with shrubbery and wood chips surrounding it.
Besides the pressure of CSU expansion, Fort Collins has seen an increase of about two degrees since 1970, corresponding to a population increase of 90,000. This is probably a little higher than Dr. Spencer’s estimates for UHI.
The Boulder weather station is similarly sited since the concrete path is just under 10 meters away.
It is at the campus of NOAA’s and NIST’s headquarters in Boulder. Anthony Watts visited the station in 2007 and took photos for the surfacestations project. Like Fort Collins, it gets similar expansion pressure due to nearby construction as seen in this aerial photo.
Here are the temperature records fro these two USHCN stations:
NCDC Fort Collins Temperatures
There is some UHI effect visible in the Boulder record below, but much less than Fort Collins.
Conclusion:
We have two weather stations in similarly sited urban environments. Until 1965 they tracked each other very closely. Since then, Fort Collins has seen a relative increase in temperature which tracks the relative increase in population. UHI is clearly not dead.
The data that is available is MR Menne’s data, is there any actual RAW data available for the 2 sites?
Kilroi1 (09:53:07) :
All kidding aside, I have a friend who works at NCAR and she tells me Kevin Trenberth is an arrogant jerk. No big surprise there.
Bill Gates was an arrogant jerk.
I hear all his work was a hoax, based on faked data.
Mike McMillan has reviewed Illinois, Iowa & Wisconsin and found lots of changes between USHCN V1 & V2.
It would be interesting to see the temperature difference vs. population difference, since that is really the correlation you are looking for.
“There is some sort of discontinuity around 1940,”
Must have been due to the japs bombing Colorado with those balloons… /sarc
I know you said there was a discrepancy in 1940, but it looked like 42 with my eyes.
Perhaps a bunch of the population, and therefore energy use, moved or shipped out for WWII?
Thanks for a wonderful report. Now we are getting somewhere.
I am surprised that there is an UHI in Boulder or Colorado Springs. Both cities are on top the plateau and in the foothills of mountains. The wind is always moving there. If you want UHI, try cities in valleys. My favorite example is St. Louis. There you should find that the UHI is HUGE. The wind moves only when a weather front is coming through. In the city, the environment’s ability to cool itself is all but nonexistent.
“…Boulder, Colorado is most famous for Jon Benet and Ward Churchill.”
I thought it was famous for Coors Brewery. When I visited the Solar Energy Research Center 30 years ago (DOE boondoggle), a side tour was to Coors. One of my all-time favorite bars, the Dark Horse Saloon (IIRC), was one of our night-time stops (not part of the DOE sponsored trip).
Back on topic: Are there any nearby rural sites, to use to calculate the UHI of Boulder and Fort Collins?
Kilroi1 (09:53:07) : “…All kidding aside, I have a friend who works at NCAR and she tells me Kevin Trenberth is an arrogant jerk. No big surprise there.”
I don’t know. I sort of like him and his famous “Trenberth Travesty.” A refreshing bit of honest questioning amidst a hailstorm of pseudoscience.
wayne (09:46:45) : “…BTW, good post.”
All posts are good, here. They all implicitly ask the question: wuzupwithat? Science is the asking of questions, not running around in circles saying, “The science is settled! The science is settled!” Only the pseudoscience is settled.
Ref – Hu McCulloch (09:35:09) :
“The area just to the north of the Boulder station is Greenlawn Cemetery, which buffers it from Boulder proper. The only development nearby is that to the south, the former National Bureau of Standards.– HM (BHS ‘63).”
________________________
Sure seems like a big cemetery would be the best place to put a city/metro weather station:-)
A Very good study !
What would be the criteria for ideal station-sitings, considered in context of a comprehensive grid pattern enabling analysts to make valid interpolations over time? Once that is determined, with built-in flexibility accounting for degrees of growth-and-change, it might be desirable –no doubt at vast time, trouble, and expense– to restart this whole project from scratch as a gift to pathetically grateful future generations.
On ‘tother hand, objectively reliable satellite readings from 1979, transparently and validly adjusted/homogenized for UHI, etc. may well have rendered the entire exercise redundant. meantime, we wouldn’t trust corrupt official measures of surface-temperatures for beans.
Lovely work, Steve and Anthony. I just loved how the different perspectives on the Fort Collins USHCN pictures told quite different stories.
What is the relative humidity history for the two sites? What is the low reading for the two sites? Are they on recording thermometers or are the readings manual and at what time of day? Do they have equal enclosures, they appear different and I am sure they have different paint.
Too many deltas for each site! Apples and oranges shouldn’t be in the same smoothie.
Well both those town (the towns) are pretty nice places; the people I think all drink Miller Lite. Maybe they never got the yellow snow warning.
The 1941 glitch deserves some explanation; but it seems clear that the rising differential trend goes all the way back to 1930.
From the separate graphs, I would say that the glitch occurred in Fort Collins; not Boulder; so the State climatologist maybe should investigate if he thinks no changes were made.
And yep, looking at those two Fort Collins pictures, I would say they haven’t changed a darn thing ; well you can now walk out of the building over to the owl box without crashing into a fence, or getting your shoes muddy on the wet grass.
It’s a bit like Oliver Cromwell’s axe in the British Museum; it’s only had two new heads, and just five new handles since Oliver last used it.
Steve and Anthony, I would say you two guys deserve a beer on this one. But get a real beer; like Negra Modello or a Newcastle Brown Ale; maybe a Hefferweiss !
Also, the Menne graphs shown above are from adjusted and homogenized data, not raw data.
Temperature trends not surprising at all. Boulder has had growth controls since 1970’s and Fort Collins has not.
Boulder CRS weather station is surrounded by Green Mountain Cemetery (north) and undeveloped open space-mountain parks to the west. Lots of industrial development to the south on the NIST/NOAA campus. Most of the local tree cover is less than 50 years old although the irrigation ditch west of the CRS dates from the late 1800’s
Prevailing winds in Boulder and Fort Collins (almost year-round) are from the west and descend from the snowy Continental Divide (13,000 ft) to Boulder (5,300 ft) over about 15 miles. “Chinook” (adiabatic) warming in winter, cool breezes in summer.
Fort Collins is farther east of the mountain front and is more of a “plains” topographic setting. Flatter terrane has allowed more residential construction all over town.
The NCAR “Castle on the Hill” is about one mile south of the Boulder CRS. May or may not have an effect, but a bunch of model-making CRAY’s and the cranial emanations of Trenberth-Amman-Solomon-Wigley-etc must generate a bit of heat. Adjustments may be required.
mikelorrey (10:39:52) : “Must have been due to the japs bombing Colorado with those balloons… /sarc”
Are the Toyotas they’ve been dropping on the US lately more effective? [I’m skeptical.]
Seriously, I’m most curious about the cause of the 1942 divergence in the T lines. The war effort didn’t really start for the US until 1942, so the discontinuity may be war-related. It goes away about 1950, so it could have been a base or similar temporary installation in Boulder. If it was a large base, the city population may have risen, too. Or did more men get drafted from Ft. Collins?
USN Japanese Language School, Boulder 1942 — 1946? Sounds too small.
As a CSU grad I’m familiar with the site. Prevailing winds are from the north west, and starting in the 1940s the farm fields to the north and west were plowed up and covered with low cost housing for returning GIs. The same prevailing winds occur in Boulder, and the area upwind of the station has not seen the development as the area up wind of the Fort Collins station. When the transfer station was built on CSU there was talk of getting another station up and calibrated to the existing one for a year or two, but I cant find anything that would indicate this was done.
It looks like in 1970, Ft C still had 20k fewer people than Boulder?
Also, I see from the links that Boulder has quite a bit higher population density – shouldn’t that matter?
And a map showing where each station was located in repect to urban development?
It is important to realize that the overlay graph is normalized. Fort Collins is cooler than Boulder by about half a degree. It used to be by 2-1/2 degrees.
The most important graph is the difference graph – the third one down.
Very interesting and well done article. No doubt the UHI effect has played some role in skewing temperature data, though I suspect it is not significant on a global basis…
Meanwhile, global tropospheric temps for March have been at or above 20 year record levels every day this month…and continue higher:
http://discover.itsc.uah.edu/amsutemps/
And it looks like we have just about reached are maximum sea ice extent for the winter season:
http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png
And should be headed back down. We did NOT see a positive anomaly this winter in the arctic (and haven’t now since 2004). I thought we might, but as the chart above shows, it didn’t quite make it. It could still turn around and poke into positive territory. More importantly though is the the trend in arctic sea ice on a year-to-year basis remains the same…down. See:
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.anomaly.arctic.png
Jim Cole (11:22:09) :
Fort Collins and Boulder are both right up against the foothills, and the topography and elevation is very similar. I ride my bike around both cities fairly often. Both cities are relatively flat, sloping up slightly to the west.
Tom in Texas (10:56:51) :
Coors is in Golden. Fort Collins is home to New Belgium (Fat Tire) and Budweiser.
38,660,924 hits
The pace is accelerating … Looks like 40,000,000 will roll around next week sometime.
The blog is becoming more and more influential.