By Jim Steele
Published in Pacifica Tribune May 14, 2019
What’s Natural
Our Urban “Climate Crisis”
Based on a globally averaged statistic, some scientists and several politicians claim we are facing a climate crisis. Although it’s wise to think globally, organisms are never affected by global averages. Never! Organisms only respond to local conditions. Always! Given that weather stations around the globe only record local conditions, it is important to understand over one third of the earth’s weather stations report a cooling trend (i.e. Fig 4 below ) Cooling trends have various local and regional causes, but clearly, areas with cooling trends are not facing a “warming climate crisis”. Unfortunately, by averaging cooling and warming trends, the local factors affecting varied trends have been obscured.
It is well known as human populations grow, landscapes lose increasing amounts of natural vegetation, experience a loss of soil moisture and are increasingly covered by heat absorbing pavement and structures. All those factors raise temperatures so that a city’s downtown area can be 10°F higher than nearby rural areas. Despite urban areas representing less than 3% of the USA’s land surface, 82% of our weather stations are located in urbanized areas. This prompts critical thinkers to ask, “have warmer urbanized landscapes biased the globally averaged temperature?” (Arctic warming also biases the global average, but that dynamic must await a future article.)
Satellite data reveal that in forested areas the maximum surface temperatures are 36°F cooler than in grassy areas, and grassy areas’ maximum surface temperatures can be 36°F cooler than the unvegetated surfaces of deserts and cities. To appreciate the warming effects of altered landscapes, walk barefoot across a cool grassy lawn on a warm sunny day and then step onto a burning asphalt roadway.
In natural areas like Yosemite National Park, maximum air temperatures are cooler now than during the 1930s. In less densely populated and more heavily forested California, maximum air temperatures across the northern two thirds of the state have not exceeded temperatures of the 1930s. In contrast, recently urbanized communities in China report rapid warming of 3°F to 9°F in just 10 years, associated with the loss of vegetation.
Although altered urban landscapes undeniably raise local temperatures, some climate researchers suggest warmer urban temperatures do not bias the globally averaged warming trend. They argue warming trends in rural areas are similar to urbanized areas. So, they theorize a warmer global temperature is simply the result of a stronger greenhouse effect. However, such studies failed to analyze how changes in vegetation and wetness can similarly raise temperatures in both rural and urban areas. For example, researchers reported overgrazing had raised grassland temperatures 7°F higher compared to grassland that had not been grazed. Heat from asphalt will increase temperatures at rural weather stations just as readily as urban stations.
To truly determine the effects of climate change on natural habitats requires observing trends from tree ring data obtained from mostly pristine landscapes. Instrumental data are overwhelmingly measured in disturbed urbanized areas. Thus, the difference between instrumental and tree ring temperature trends can illustrate to what degree landscapes changes have biased natural temperature trends. And those trends are strikingly different!
The latest reconstructions of summer temperature trends from the best tree ring data suggest the warmest 30-year period happened between 1927 and 1956. After 1956, tree rings recorded a period of cooling that lowered global temperatures by over 1°F. In contrast, although tree rings and instrumental temperatures agreed up to 1950, the instrumental temperature trend, as presented in NASA graphs, suggests a temperature plateau from 1950 to 1970 and little or no cooling. So, are these contrasting trends the result of an increased urban warming effect offsetting natural cooling?
After decades of cooling, tree ring data recorded a global warming trend but with temperatures just now reaching a warmth that approaches the 1930s and 40s. In contrast, instrumental data suggests global temperatures have risen by more than 1°F above the 1940s. Some suggest tree rings have suddenly become insensitive to recent warmth? But the different warming trends are again better explained by a growing loss of vegetation and increasing areas covered by asphalt affecting temperatures measured by thermometers compared with temperatures determined from tree ring data in natural habitats.
Humans are increasingly inhabiting urban environments with 66% of humans projected to inhabit urban areas by 2030. High population densities typically reduce cooling vegetation, reduce wetlands and soil moisture, and increase landscape areas covered by heat retaining pavements. Thus, we should expect trends biased from urbanized landscapes to continue to rise. But there is a real solution to this “urban climate crisis.” It requires increasing vegetation, creating more parks and greenbelts, restoring wetlands and streams, and reducing heat absorbing pavements and roofs. Reducing CO2 concentrations will not reduce stifling urban temperatures.
Jim Steele is the retired director of San Francisco State University’s Sierra Nevada Field Campus and authored Landscapes and Cycles: An Environmentalist’s Journey to Climate Skepticism.
Contact: naturalclimatechange@earthlink.net
A popular children’s story of my youth was “Mr. Flibbertyjib,” about a fussbudget who lived in a city and got annoyed about car horns, garbage trucks, etc. until he couldn’t sleep. He longed to move out to the country for peace and quiet.
When he got his wish, the silence drove him crazy until the occasional cricket or tree frog made him jump a foot. Mr. Flibbertyjib slept worse than before. He couldn’t wait to get back to the city. When he did, he felt grateful for familiar surroundings and slept like a baby.
The moral of the story is that people are always discontented, until they learn to be grateful. Joni Mitchell’s song, “Don’t it always seem to go that you don’t know what you’ve got til it’s gone?” is a similar theme.
I believe that much of today’s climate panic is Flibbertyjibism. It’s city people with a distorted view of the way things are supposed to be, without knowing how good they’ve got it. The urban heat island effect is too subtle for them. They’re jaded from crass entertainments, and crave melodrama — facts be damned. Next to nobody would notice a change in the weather, or climate, if it weren’t for the relentless propaganda.
I was a farmer for 34 years, and remain acutely attuned to weather, but city folk don’t believe a word I say.
That reminds me of a joke.
So… Alaska? Svalbard? I notice you don’t include the arctic in this.
and the USA is a small part of the world…
Why does the MSM never pick up on this kind of news? Lies of ommission are as bad as lies of commission.
Trying to distinguish a general trend from data with Urban Heat Island biases in some of the sites has apparently led to general “corrections” of the data, rather than examining the individual stations.
That sort of thing is probably why the satellite measurements have diverged from land station databases like GISSTEMP or HADCRUT.
I live the majority of my entire existence in a temperature well above the global average. I could easily tolerate a change of a few degrees above this, and I would definitely be uncomfortable at a few degrees below this.
I’m good at about 75 F. air temp. I deal well with upper 70’s, 80’s, and tolerate 90 (F.)
Many people in the developed world live in climate controlled environments most of their lives, and have no relationship to the anything other than artificially maintained temperatures. Also, in these climate-controlled enclosures, many people live most of their lives in higher CO2 environments than the official measure.
Many people, thus, have no clue what they have been led to believe that they should be alarmed about. They are already living out of those idealized bounds, … every … single … day.
“Although it’s wise to think globally, organisms are never affected by global averages. Never! Organisms only respond to local conditions. Always! ”
Yes, yes yes!
And I’ve been saying as much for decades.
Climate, just like weather, is a local affect of many LOCAL parameters and variables.
All this talk of Global Climate is just BS . An notion from the faulty idea that if you average some parameters within chaotic system you can find a trend, that’s just not possible as the chaos is the signal that sets the trend. Go ask the butterflies.
Hmm, what should I wear today? I better check the global average temperature.
Another great post.
“Despite urban areas representing less than 3% of the USA’s land surface, 82% of our weather stations are located in urbanized areas.” A bookmark in my brain for that one.
Jim, I do have a question about one statistic. Satellite data reveal maximum surface temperatures in forest areas are 36F cooler than in grassy areas.
Is that typo? I understand why they would be cooler but this is a very big difference.
Could you expand on that? Would other variables be involved?
Facts, logic and good old common sense are things foreign to the liberals, and the Left. All they can see, apparently, is the tip of their own noses. Common sense tells us that the cities, with all that concrete and brick work is GOING to retain more heat than the country side, but chicken little’s think it means the end of the world. Maybe they just need to drive OUTSIDE the city and see for themselves, that the world is doing just fine! WITHOUT their fear mongering! Just sayin…
Jim
It has been a few years since I started following this topic. Early on, I did a search for historical temperature records. I ran across a California map that was apparently part of a PhD dissertation. What it basically showed was that there was a correlation between the average temperatures and population growth of counties. Notably, there was a cooling in the NE corner of the state. Alas, like so many things on the internet, it apparently has disappeared. Recent attempts to find it have failed.
Not too long ago Tony Heller posted a historical graph of temperatures in a locality. It did seem like variablility decreased with time. Could changes in variability be a proxy for the impact of the heat island effect?
Opening your eyes, nose, and feeling the breeze will tell you more about the weather than any weather channel. Doing it daily will tell you more about the climate than any laboratory experiment or computer program which only work with tiny samples of our weather, much of which is suspect data.
Jim, is there a decimal missing in this statement: “surface temperatures are 36°F cooler than in grassy areas, and grassy areas’ maximum surface temperatures can be 36°F cooler than the unvegetated surfaces of deserts and cities. “?
BTW, doesn’t this 82% of stations in urban/developed areas contradict Mosher’s recent article? https://wattsupwiththat.com/2019/05/07/willis-favorite-airport/
All that wall space in major urban areas is an opportunity to grow things like lettuce and tomatoes. This would bring so many benefits: cooling urban daytime highs, reduce pollution, provide local food sources that are fresher and cheaper, aesthetics, reduced land use change from agriculture, and get urban dwellers outside more. Too bad environmental science has been hijacked by the mentals.
Quite apart from loss of vegetation and the presence of heat-absorbing structures, the amount of waste heat produced in cities must be a major factor here: by vehicles, by heating buildings in cold weather, and by air conditioning in hot weather. Anything actually burned in situ will also produce a local increase in carbon dioxide, although the local effect of this would be debatable.
I remain dubious of tree-mometers, however thank you Jim Steele good post.
Funny after 40 years and ever increasing hysteria orchestrated by our bureaus, we are still at the start point.
Is it warming?
Or Cooling?
We really cannot say, “It depends” to quote Bob Carter, but to witness the current pseudo-mass hysteria over assumed warming, reinforces my cynicism.
We remain at the “Number of angels on the head of a pin” stage after wasting billions of dollars.
Our claimed signal(the warming) is less than the uncertainties in our records.
Historically the proper answer may be “Duh”.
Urbanization has two obvious consequences, we have the majority of our voting population cut of from the weather and concentrated pockets of waste heat.
But who needs logic?
Emoting ..feels so good?
NYC will be having crisis after crisis now.
https://www.zerohedge.com/news/2019-05-17/new-york-ditches-gas-pipeline-proposal-despite-soaring-electricity-bills
I was dispatched to NYC in 05 to repair their grid when a heatwave fried it. No breeze at all either.
All the grandiose plans for offshore wind will be a disaster, no wind during heateaves and of course the chance or three of annual hurricanes that will destroy them.
Best of luck!
Here in the midwest there are a number of changes that make it difficult for me to assume a constant environment. One, is that much of the “hedge rows” put in after the dust bowl have been removed to allow bigger fields for bigger equipment. This not only removes cooling vegetation but also removes any resistance to the wind at the surface (hopefully this won’t result in another dustbowl). Two, is that many, many rural roads that used to be gravel or even dirt have been paved with asphalt. Other roads have been widened through rural areas to accommodate traffic between urban areas (multilane interstates and highways). This simply has to result in a temperature gradient that increased surface winds would spread over a wider area.
I’m sure warmista’s would say the changes to temperatures are minimal. However, when forecasts of one-hundredth’s or one-thousandth’s are being tossed around, you are talking in the realm of minimal.
Interesting thoughts, and UHI doubtlessly creates an upward bias. The Science on UHI is more demonstrable and settled that the Greenhouse Effect.
With these thoughts in mind, shouldn’t we expect to see a divergence between terrestrial and ocean surface temperatures?
To expand on the concept: A random selection of temps from 30 cities experiencing substantial growth should be compared to randomly selected ocean locations of identical latitude.
I’m sure Dr’s Spencer and Christy could compile this information in short order.
Jim Steele,
Another thoughtful presentation – Thanks!
This post sets out to disinform: “some scientists and several politicians claim we are facing a climate crisis.”
No. The vast majority of scientists and nearly every politician outside the US.
“This prompts critical thinkers to ask, “have warmer urbanized landscapes biased the globally averaged temperature?””
But from the link provided the answer is no:
“The small size, and its negative sign,
supports the key conclusion of prior groups that urban warming does not unduly bias
estimates of recent global temperature change.”
Completely refuting the lie: “Thus, we should expect trends biased from urbanized landscapes to continue to rise.
And so with the cited evidence showing the opposite of the supposition the author bizarrely but predictably concludes therefore: “Reducing CO2 concentrations will not reduce stifling urban temperatures.”
Despite the obvious contradiction and the maligned use of tree ring data, the angry mob wave their pitchforks in furious, credulous agreement. SMFH.
Loydo, Seems like it is you who set out to disinform.
Please read the whole article more carefully and put on your thinking cap.
I acknowledged “some climate researchers suggest warmer urban temperatures do not bias the globally averaged warming trend.” You simply gave an example of what I had written and from a link I gave you. But oddly you suggest there is a lie.
I continued, “They argue warming trends in rural areas are similar to urbanized areas. So, they theorize a warmer global temperature is simply the result of a stronger greenhouse effect. However, such studies failed to analyze how changes in vegetation and wetness can similarly raise temperatures in both rural and urban areas.”
Studies using rural vs urban comparisons do not account for landscape changes that affect temperarturs in both places. The tree ring data reveals the true difference.
Tom Gels Thorpe, May 17, is 100 % right. Hence the difference between
city folk and country folk.
We have just this problem in Australia, the country folk used to have a
political party called “The Country Party”, but some years ago it found that
with the development of mining, the money for re-elections was going to the
city, so they decided to change their name to “The National Party”.
They entered into a somewhat uneasy coalition with the larger city
based Liberal Party (Conservative) but the country folk now complain that
they are neglected as the money being in the city, their “Representatives “”
are far more interested in where the big mining interests are, and what they
want
The result is of course that small parties such as the “”Shooters and Fishers
Party “” are emerging, and at State level do quite well. Today being a
Federal electron day it will be interesting to see what results.
The ex leader of the Nationals Barnaby Joyce is fighting against this City base thinking , so as its almost a certainty that the Labour Party will win, expect a
split between the two Conservative parties.
MJE VK5ELL