Home/BlogThis is the first of what will likely be a series of posts regarding urban heat island (UHI) effects in daily record high temperatures. My previous UHI work has been using the GHCN monthly average station data of “Tavg” (the average of the daily maximum [Tmax] and minimum [Tmin] temperatures). So, I’m moving from Tavg to Tmax (since record high temperatures are of so much interest), and daily rather than monthly values (although I will also sometimes include monthly results to provide context).
This post is mostly a teaser. Toward the end I will describe a new dimension to our UHI work I’m just starting.
The 2024 Poster Child for U.S. Warming: Palm Springs, CA
I was guided by a Google search on U.S. record high temperatures for 2024, and it seems Palm Springs, California was the place to start.
With a name like “Palm Springs” this place sounds like a wonderful spot to lounge under palm trees and enjoy the cool, refreshing spring water that surrounds you. Instead, the location is largely a desert, with the original downtown spring spitting out 26 gallons a minute of hot water. The “palms” do exist… they are “desert palms”, naturally growing in clusters where groundwater from mountain snowmelt seeps up through fissures connected to the San Andreas fault.
Like all U.S. metropolitan areas, the population growth at Palm Springs in the last 100+ years has been rapid. Even in the last 50 years the population has nearly doubled. Natural desert surfaces have been replaced with pavement and rooftops, which reach higher temperatures than the original desert soil, and the “impervious” nature of artificial surfaces (little air content) means the heat is conducted downward, leading to long-term storage of excess heat energy and, on average, higher temperatures. More on “impervious” surfaces later….
The Palm Springs Airport Weather Observation Site
The following Google Earth image shows the current location of the official ASOS (Automated Surface Observing System) site at the Palm Springs Airport, which recorded an all-time record high temperature of 124 deg. F on July 5 of this year.
What is somewhat amusing is that ASOS meteorological instrument siting guidance favors natural surfaces for placement, but since most of these weather stations are at airports (and since they primarily support aviation weather needs, not climate monitoring needs), the “natural” location is usually right next to runways, aircraft, and paved roads.
The next Google Earth image is zoomed out to show the greater Palm Springs area, with the ASOS site in the center (click on the image to zoom, then click to zoom more).
Record July Temperatures and Urbanization
It only makes sense that people want to know the temperature where they live, and most of the U.S. population resides in urban or suburban locations. Yet, the temperatures they experience are, probably without exception, higher than before people moved there and started building roads, buildings, and airports.
But what is misleading for those following the global warming narrative is that record high temperatures reported at these locations almost always mention climate change as a cause, yet they have no way of knowing how much urbanization has contributed to those record high temperatures. (Remember, even without global warming, high temperature records will continue to be broken as urbanization increases).
As mentioned above, on July 5, 2024 Palm Springs broke its all-time high temperature record, reaching 124 deg. F. There are 26 other daily GHCN stations within 40 miles of Palm Springs, all with varying levels of urbanization, but even more importantly, at very different elevations. If we plot the high temperatures reported for July 5 at those stations as a function of station elevation, we see that Palm Springs is an “outlier”, 5 degrees warmer than would be expected based upon its elevation-corrected expected temperature (the dashed regression line):
Now, keep in mind that many (if not most) of those 26 surrounding stations have their own levels of urbanization, making them hotter than they would be in the absence of pavement and roofs. So, that 5 deg. F excess is likely an underestimate of how much urban warming contributed to the Palm Springs record high temperature. Palm Springs was incorporated in 1938, and most population growth there has been since World War II.
If you are curious how the previous plot looks for the average of all July temperatures, here it is:
For the month of July, Palm Springs averaged 3 deg. F warmer than the surrounding stations (after adjusting for elevation effects, and keeping in mind that most of the *other* stations likely have their own levels of urbanization).
Clearly, Palm Springs has had spurious warming influence from the airport and surrounding urbanization which did not exist 100 years ago. But how much?
Impervious Surface Data as a Surrogate for Urbanization
This blog post is a prelude to a new project we’ve started where we will compare daily (as well and monthly) temperatures to a relatively new USGS dataset of yearly impervious surface coverage from 1985 to 2023, based upon Landsat data. I had previously experimented with a “Built Up” dataset based upon Landsat data, but it turns out that was just buildings. The “impervious surface” dataset is what I believe will have the greatest direct physical connection to what causes most UHI warming: roads, parking lots, roofs, etc. I think this will produce more accurate results (despite being only ~40 years in length) than my population density work (which is, we hope, close to being accepted for publication).
Exactly what I’ve been saying for years. And since urbanization follows population growth, there is certainly a strong correlation between population growth and global warming, probably more than any perceived greenhouse gas driver.
*** Yes, I’m sure there will be a strong correlation between population density and impervious surfaces. But what about when population levels off, and prosperity/wealth increases? More Dollar Generals/Wal Marts/parking lots, etc? That effect is what I’m interested in investigating, because our population density calculations suggest little UHI effect since the 1960s. We shall see. –Roy
Unfortunately, wealth or the value of the once proud US dollar are inversely correlated either the number of Dollar Tree and Dollar General stores that pop up or exist in an area now. Back in he prosperous years the number of Macys, Nordstroms and Sears stores were correlated with wealth.
It seems both satellite and land-based temperature measurements tend to skew high as they age.
“impervious surface”
also implies improve drainage.
…improved drainage…
Roy,
The two graphs above can also be used as evidence of the Lapse Rate Feedback, which refers to how the vertical temperature profile changes as the Earth’s surface warms.
Rgrds.
*** “Lapse rate feedback” is the change in top-of-atmosphere IR radiative flux only due to a change in lapse rate during global warming. Evidence that a lapse rate exists (whether weak or strong) does not prove whether lapse rate feedback is either positive or negative. –Roy
“‘Lapse rate feedback’ is the change in top-of-atmosphere IR radiative flux only due to a change in lapse rate during global warming.”
Roy, I know you’re the expert here, but it is my understanding that the Lapse Rate Feedback is the result of an upper troposphere that warms more than the surface in a warming climate. This results in greater TOA radiation to space than the equilibrium case where the surface and TOA are warming at the same rate, i.e. an unchanging lapse rate.
“Evidence that a lapse rate exists (whether weak or strong) does not prove whether lapse rate feedback is either positive or negative.”
As I explain above, a steepening lapse rate results in negative feedback.
Rgrds
“greater TOA radiation to space than the equilibrium case”
So the radiation (both ways) is the same then.
What is “the radiation (both ways)“?
To space and the surface.
And?
What goes down must also go up (and vice versa).
Hi there, a friend of mine shared this URL on Facebook and I in turn shared it and was subsequently flagged and restricted from further posting on my account because they said this is misinformation and spam.
Does it make much sense to check for Tmax? The UHI has a specific profile, strongly affecting Tmin (especially in summer), but barely Tmax, as far as I know.
Anyway, I’d have a little request for you. Could you possible check for the relation between cloudiness (be it in oktas or METAR format) and surface temperature? I have done it, I know what you will find and it is jaw dropping..
Good point about Tmax, that is early undergraduate meteorology, at the times of daily maximum temperatures the air is almost always moving and mixing in such a way that “small” local heating influences have little impact at the thermometer.
The only way to negate this conclusion is for the wind to be very light, which almost always happens only at night.
Take a look at Alice Springs:
https://youtu.be/vEYKkKaQlWI?si=oZ2ss5Q-vk7o_KGW
I commend their effort, but if they did some additional research they would have found that Alice Springs moved their station in 1950’s. As such, if you want the data in V.4, you need to filter 1902 – 1950, and voila, Alice Springs appears. You could then filter the balance for the data on the new location. I think there was a 10 year overlap on data if memory serves me, and I don’t know the exact years of the change.
BillyBob
Never trust CO2isLife – regardless what he talks about.
GHCN daily, GHCN V4’s origin, shows this about ALICE SPRINGS in its station list:
ASN00015540 -23.7100 133.8683 580.0 ALICE SPRINGS POST OFFICE
ASN00015590 -23.7951 133.8890 546.0 ALICE SPRINGS AIRPORT
ASN00015634 -23.6833 133.8500 591.0 ALICE SPRINGS CONNELLANS
The inventory file shows this:
ASN00015540 1878 1953
ASN00015590 1750 2024
ASN00015634 1940 1941
The third station is of no interest. ASN00015590’s start in 1750 lasted for no longer than a year and first continued in 1942.
Combining the two remaining stations into an anomaly time series gives:
https://drive.google.com/file/d/1JrKJ3VtEk7G72OqRlRT5poZo3a5JJdDz/view
*
You get a big laugh when hearing people saying:
” What? Airport? UHI! UHI!! UHI!!! ”
and see that about 5 flights per day start / land there…
https://www.alicespringsairport.com.au/traveller/flights/departures
*
It won’t take much time till BigFeetSmallBrain comes along and tells us that ‘NOAA has only 1500 stations worldwide’, oh Noes :–)
“But what is misleading for those following the global warming narrative is that record high temperatures reported at these locations almost always mention climate change as a cause, yet they have no way of knowing how much urbanization has contributed to those record high temperatures. (Remember, even without global warming, high temperature records will continue to be broken as urbanization increases).”
I remain puzzled as to why you are embarking on this exercise.
Question 1
Why is it so important that people are told the magnitude of the UHI component of any record temperature?
Surely the fact that a record maximum temperature has been recorded is the important fact to them. Whether UHI contributed 0.01, 0.1 or 1.0 degrees is somewhat irrelevant. They feel the heat – end of story.
Question 2
Are you trying obtain a better estimate of the UHI effect –
something better than previous estimates (e.g. Oki)? Again, by how much do you expect to improve previous estimates (.01, .1 or 1.0 degrees) ?
Question 3
Are you trying to cast doubt on the trends in the global surface temperature record in order to revise down the contribution of climate change? Good luck with that. You will have to reconcile any such results with observed trends over the oceans (no UHI effect there), observed changes in the proxy records of snow (look up Mt Fuji),ice (retreating glaciers and sea ice), flora and fauna etc.
Question 4
Maybe you are trying to link to the trends in the satellite data? But I am not sure what this achieves given the very different quantities involved.
One of the dumbest posts in years, on every “point”. Prof P fails to grasp that the problem is the incorrect interpretations of “climate change”, and causes thereof, that are thoughtlessly thrown around by pseudo-academia, bureaucrats and the idiotic media. It should be obvious why UHI has to be rigorously addressed. This clown is a “professor” of cultism only.
Thanks GW.
I am sorry you are so triggered.
“It should be obvious why UHI has to be rigorously addressed.”
It has been addressed for decades. It is nothing new.
Tell me, what do you think it is that needs addressing?
I think you need to clarify your rather silly and poorly written questions. On the surface you seem to say “screw the science, it is the narrative — stew-pid” (forbidden word when spelled correctly).
In case it is lost on the good “professor”, Dr Spencer is doing science here, and he is specifically trying shed light on much of the fallacy involved in the narrative.
For my part, it is the hype involved in the narrative that puts the “hoax” in climate change. There is a strong enough suggestion in the data that increasing CO2 is having an effect on the earth. There is no need to lie about it or push the hype. The question of the follow-on effect on climate is still an open question ranging from mild to possibly extreme effects. There is no amount of currently available data or computer simulation that can provide a valid prediction within that range of uncertainty.
Prof P, you say that the urban heat island has been know about for a long time. That is technically true. But the details are still not know, despite the excellent work or Dr Christy & Dr Spencer.
Can you point to a set of formula that predicts the UHI of Oxford city? It’s a small city in England, don’t know if you heard of it?
Is it over-simplistic to point out that the warming rate over the global oceans isn’t all that different to the warming rate over global land? We also know about thermal lag of oceans, right?
We can hardly attribute this ocean warming to UHI, can we?
TheFinalNail,yes there is a lag but not exactly know as the ocean has a range of temperatures and it is being mixed all the time. Be suspicious of any definitive claim as the ocean hadn’t been fully mapped yet.
Wind speed is a vital variable for how much a Tmax value is altered by UHI. To me any claim for UHI corruption of a record high temperature must come with a figure for wind speed, which must be exceptionally low for the claim to stand.
Tmax values are effectively averages over quite large areas due to turbulent mixing of air … except when there is very little wind.
There is also the fact that horizontal radiation from surfaces (such as roads and runways) cannot heat the horizontal surface that the thermometer sits above.
ark…”Lapse rate feedback is the change in top-of-atmosphere IR radiative flux only due to a change in lapse rate during global warming.
***
The word feedback is being thrown around in the alarmist climate change arena liberally without meaning and out of context. Any meaning implied is just that, an inference.
A feedback in physics has several contexts but the basic context is that it is part of a system where ‘something’ is fed back to ‘somewhere’ in order to affect change in the system. I defy anyone to apply that to ‘lapse rate feedback’ either as part of a system or something fed back in the system.
Ergo, it’s one thing to coin a phrase and quite another to explain it. I have read Gavin Schmidt of NASA GISS fumbling to explain feedback, but he did not even come close to the definition of feedback in physics. Rather, his definition was vague and conjured.
Schmidt used vague terminology like I used above where ‘something’ is fed back, but he went as far as to claim that something caused amplification. There is no system in physics where feedback alone can cause amplification since it is only part of an amplified system. A standalone amplifier is required which cam amplify with or without feedback.
A lapse rate as applied to the atmosphere is simply an orderly decline in the kinetic energy of air molecules with altitude. As such it is simply an observation of air temperatures declining with altitude.
The definition above does not specify a system where a factor is fed back from an output to an input in order to affect the rate of
temperature change. In fact, the definition does not even specify what is changing and how it is changing, it merely ‘suggests’ a change in lapse rate is due to a mysterious ‘global warming’.
The alleged cause, global warming, has never been adequately explained, let alone proved. It is presumed to be caused by the injection of CO2 into the atmosphere by humans but the method of warming has never been explained. So, how can a feedback be claimed for a process of unknown origin?
A refined analogy offered as an intuitive way to conceptualize the lapse rate feedback.
Imagine the atmosphere is like a pipe carrying heat away from Earth’s surface (our heat source) up to the cooler, upper atmosphere where the heat can eventually radiate to space.
Base Case (Constant Pipe Diameter): In a stable climate scenario, the pipe has a fixed diameter, which means it allows a certain amount of heat to flow from the warm surface to the cooler upper atmosphere, keeping the surface temperature balanced over time.
Positive Feedback: If we decrease the pipe’s diameter but keep feeding heat into the surface at the same rate, the pipe now restricts the flow of heat. Less heat reaches the upper atmosphere, so more heat accumulates near the surface. This creates a positive feedback effect: as the surface warms, the reduced ability to transport heat upward allows even more warming to build up at the surface, amplifying the warming effect.
Negative Feedback: On the other hand, if we increase the pipe’s diameter (analogous to a steep lapse rate, where heat is more effectively transferred upward) it becomes easier for heat to flow from the surface to the upper atmosphere and the temperature of the upper atmosphere increases; a warmer upper atmosphere will radiate energy to space at a much greater rate.
In the atmosphere, the “pipe diameter” changes as the lapse rate adjusts with warming or cooling at different altitudes.
Ah, yes, the old thought experiment in lieu of an actual scientific explanation based on observation.
Allow me to present an actual, testable example of positive amplification-related feedback, then let us compare the actuality with the thought experiment.
An electronic amplifier, transistor, takes a smaller signal as an input and an amplified signal as an output. Consider the transistor for now as a black box that can take a small signal and output an amplified signal.
It is vital to understand that amplification is not about getting something for nothing. The input signal, as a voltage or a current, comes from a device like a microphone that can output a voltage/current based on a diaphragm activated by voice air pressure creating a voltage/current as the diaphragm pushes a coil of wire into and out of a magnetic field.
The microphone signal is far too low in power to hear with the human ear so we must amplify it to a higher power level. The transistor cannot supply that increased power, it must be supplied by an external source like a power supply. All the transistor does is impedance match the small input signal to the higher power output signal where a higher current is available. If we can modulate that higher current using the smaller input current, we can replicate the lower power input signal in the output of the transistor and the replication is called amplification.
Thus far, we have not mentioned feedback, either positive or negative. Also, note that the signals we have been amplifying are alternating current/voltage signals. In this case, a feedback signal is a small signal fed back from the amplified output signal to the unamplified input signal. Depending on the phase of the feedback signal, it wither adds to or subtracts from the input signal.
It is important to understand that the feedbacks referenced in alarmist climate jargon are vague and inferred rather than being easily explained scientifically. For example, the albedo effect is claimed as a feedback but it doesn’t really fit the true, scientific meaning of a feedback. Nothing is fed back, albedo is a simple case of the reflection of solar energy by the surface. That is not technically a feedback system.
If the feedback signal adds to the input signal in a transistor amplifier, then during each cycle of amplification, the input signal becomes larger and so does the output signal. It is plain that soon, the output signal will increase exponentially into a condition called runaway, as the output signal rises toward infinity. Of course, it’s amplitude is controlled by the ability of the power supply to deliver current. In that role PF has no real use.
PF is featured in oscillators but the feedback is not done on a one to one relationship. A portion of the output is sent back to an oscillator mechanism in the input circuit to make up for losses in the mechanism and does not affect amplification per se.
The equivalent for runaway in climate lingo is the tipping point theory. However, the positive feedback inferred has no explanation in the atmosphere. For it to operate, there has to be an external source of heat, and to understand that we need to understand heat and how to increase it.
Heat is the kinetic energy associated with atomic motion. In other words, energy is required to increase that motion and since we have no idea what that energy is, we have called it heat. Alarmists think we can increase that heat by CO2 in the atmosphere absorbing surface infrared energy emission and back-radiating the IR to the surface to produce heat.
Not possible. The 2nd law forbids a transfer of energy from a colder part of the atmosphere to a warmer surface. Also, there are significant losses in the process and to create heat, those losses must be overcome. Alarmists think the losses are supplied by the Sun but that is ingenuous. There is a time factor involved and the Sun would have to deliver heat instantaneously to make up for the lost energy.
Your pipe thought experiment misses the actuality in the atmosphere. The original concept was a lapse rate feedback which was unexplained. Looking at the actuality, air heated by the surface rises naturally in an ever-decreasing air pressure created by an ever-decreasing gravitational field. There is no way to control that process, as with a transistor, so there is no point bringing in a concept of feedback.
The closest feedback to such a process is servo-type feedback but there is no amplification there. It is strictly mechanical in the sense that a sensor on an output relays information back to a controller and the controller does something to control the output.
Example. An electric motor has a tachometer attached to the shaft. The tach measures the shaft RPM and feed a voltage back to a motor controller where a positive voltage indicates the RPM is over a set point RPM and a negative voltage means its under. A zero voltage means the RPM is correct. The controller reacts to the feedback voltage by increasing motor current, which increases the RPM, or cuts the current to decrease it.
There is no way to make that work with the concept of lapse rate feedback. If you think you can explain it, drop the thought experiment and present a realistic analogy based on what lapse rate means.
.
https://www.drroyspencer.com/2024/11/urban-legends-of-climate-change-palm-springs-california/#comment-1694251
Q.E.D.
The link above contains a reply to Roy’s comment. Expanding on that reply…
The water vapor feedback and lapse rate feedback are interdependent.
As the Earth’s surface warms, more water evaporates, increasing the amount of water vapor in the atmosphere.
The presence of additional water vapor affects the lapse rate. In a humid atmosphere, the lapse rate is lower because water vapor releases latent heat as it condenses higher in the atmosphere. This latent heat release warms the air at those altitudes, slowing the rate of temperature decrease with height which traps more heat near the surface. This effect means that as water vapor increases, the lapse rate feedback generally shifts toward positive feedback, amplifying warming at the surface.
This linkage is particularly pronounced in the tropics, where humid air dominates and latent heat release from water vapor condensation significantly influences the lapse rate. In polar regions, where the air is much drier, the lapse rate feedback and water vapor feedback are less strongly linked, resulting in regional differences in climate response.
This interdependence makes them critical components of the overall climate feedback system and highlights why they are both central to climate sensitivity.
*** In climate models, water vapor feedback and lapse rate feedback are negatively correlated. The greater the (positive) water vapor feedback, the greater the (negative) lapse rate feedback. That’s for GLOBAL averages. I wouldn’t assume the same is necessarily true for desert climates. -Roy
test
roy and ark…perhaps Roy would be good enough to go into this in more detail in an article. I am not about to allow ego to prevail and question an expert like Roy on what is meant by lapse rate and/or feedback. What I am questioning is the meaning of lapse rate and feedback in climate science as opposed to physics.
Intuitively, lapse rate makes sense to me for a theoretical static atmosphere. I get it that temperatures decrease with altitude and I accept that the decline is relatively linear in the troposphere. I get it that temps begin to warm slightly in the stratosphere due to oxygen absorbing solar UV and warming.
The thing that bothers me is the claim by some climate scientists that the lapse rate is produced by rising heated air masses from the surface. Without gravity, there would be no atmosphere never mind a lapse rate, all the gases having drifted off to space.
It is also painfully obvious to me that air pressure declines with declining gravity, the strength of which is measured from earth’s centre. Therefore, air pressure is lower at sea level and declines linearly the further we are from that centre. That’s why air pressure at the top of Everest, at nearly 30,000 feet (8800 metres) is 1/3rd the pressure at sea level.
*** There is very little change in the force of gravity from the surface to high altitude in the atmosphere… pressure primarily changes due to the weight of the overlying atmosphere compressing the atmosphere below — Roy
Every so often I see an admission that the lapse rate is derived from gravity. I also see several definitions such as environmental lapse rate, adiabatic lapse rate and so on. That suggests the lapse rate is defined in different ways to accommodate rising, heated air parcels.
*** You need to read up on atmospheric thermodynamics.. your reasoning is muddled here. Air pressure (like pressure at depth in the ocean) is due to the weight (mass) of the overlying atmosphere. The troposphere’s temperature profile “wants” to have an extremely steep lapse rate, due to surface heating by the sun combined with radiative destabilization by the greenhouse effect. But convective overturning kicks in, making the troposphere have the observed lapse rate. The temperature profile is NOT due to a change in pressure: example, the stratosphere, which has nearly constant temperature across 2 orders of magnitude change in pressure– Roy
Therefore, to claim a lapse rate feedback one must necessarily explain what is meant by feedback. I get it that climate scientists have likely created their own definition for feedback and I don’t care about that. I do care when that same feedback is claimed to produce warming because that contradicts the definition of such a feedback in physics which is defined clearly as …
G = A/(1 + AB)
The A means amplification (gain) and in the denominator AB means multiplying that gain factor by a fraction of A (the feedback signal B) which is feedback to the input of the amplifier.
It is clear that B cannot produce amplification, it can only modify it by sign and by magnitude.
The type of feedback being implied cannot amplify. It is akin to servo feedback where the sign, not the amplitude, of the feedback sign signals to a controller to increase current to a motor or decrease it, so as to control the motor speed.
On the other hand, no positive feedback can work without an amplifier. If you have a purely passive network in electronics, using resistor and non-amplifying devices, positive feedback is not possible.
Before we even begin talking about lapse rate feedback we must first define lapse rate then define the feedback mechanism. Ark has done neither, he has simply consulted an authority figure and regurgitated what they said.
Roy,
Yes, the water vapor and lapse rate feedbacks are inversely correlated. Also, in modern Earth System Models the two feedbacks are, generally, emergent properties which is to say they are not directly hard-coded into the simulations.
To a non-expert such as myself the emergent nature of these two interrelated feedbacks serves as a quality check on the simulations. It shows that the built-in fundamental equations describing atmospheric physics, thermodynamics, radiative transfer, and fluid dynamics, are faithful representations of the system.
Granted, certain processes which influence these feedbacks such as cloud formation and small-scale turbulence parameterized, the feedbacks themselves still emerge from how these parameterized processes interact with the overall system.
Rgrds
test again
roy and ark…perhaps Roy would be good enough to go into this in more detail in an article. I am not about to allow ego to prevail and question an expert like Roy on what is meant by lapse rate and/or feedback. What I am questioning is the meaning of lapse rate and feedback in climate science as opposed to physics.
Intuitively, lapse rate makes sense to me for a theoretical static atmosphere. I get it that temperatures decrease with altitude and I accept that the decline is relatively linear in the troposphere. I get it that temps begin to warm slightly in the stratosphere due to oxygen absorbing solar UV and warming.
The thing that bothers me is the claim by some climate scientists that the lapse rate is produced by rising heated air masses from the surface. Without gravity, there would be no atmosphere never mind a lapse rate, all the gases having drifted off to space.
It is also painfully obvious to me that air pressure declines with declining gravity, the strength of which is measured from earth’s centre. Therefore, air pressure is lower at sea level and declines linearly the further we are from that centre. That’s why air pressure at the top of Everest, at nearly 30,000 feet (8800 metres) is 1/3rd the pressure at sea level.
Every so often I see an admission that the lapse rate is derived from gravity. I also see several definitions such as environmental lapse rate, adiabatic lapse rate and so on. That suggests the lapse rate is defined in different ways to accommodate rising, heated air parcels.
Therefore, to claim a lapse rate feedback one must necessarily explain what is meant by feedback. I get it that climate scientists have likely created their own definition for feedback and I don’t care about that. I do care when that same feedback is claimed to produce warming because that contradicts the definition of such a feedback in physics which is defined clearly as …
G = A/(1 + AB)
The A means amplification (gain) and in the denominator AB means multiplying that gain factor by a fraction of A (the feedback signal B) which is feedback to the input of the amplifier.
It is clear that B cannot produce amplification, it can only modify it by sign and by magnitude.
The type of feedback being implied cannot amplify. It is akin to servo feedback where the sign, not the amplitude, of the feedback sign signals to a controller to increase current to a motor or decrease it, so as to control the motor speed.
On the other hand, no positive feedback can work without an amplifier. If you have a purely passive network in electronics, using resistor and non-amplifying devices, positive feedback is not possible.
Before we even begin talking about lapse rate feedback we must first define lapse rate then define the feedback mechanism. Ark has done neither, he has simply consulted an authority figure and regurgitated what they said.
“That suggests the lapse rate is defined in different ways to accommodate rising, heated air parcels…we must first define lapse rate”
Gordon, you are just not capable of learning basic meteorology since adiabatic means the parcel in the 9.8C/km dT/dz earthen lapse rate derivation is NOT heated. The parcel temperature is defined always that of the surroundings along with its pressure being defined the same as its surroundings.
A lapse rate is defined as a rate of decrease of something which even Gordon ought to understand but can’t.
Argentina withdraws delegates from climate summit as Milei heads for Mar-a-Lago.
https://www.cnn.com/2024/11/13/americas/cop29-argentina-withdraws-milei-intl-latam/index.html
Roy…above you made offered this reply…
“You need to read up on atmospheric thermodynamics.. your reasoning is muddled here. Air pressure (like pressure at depth in the ocean) is due to the weight (mass) of the overlying atmosphere. The tropospheres temperature profile wants to have an extremely steep lapse rate, due to surface heating by the sun combined with radiative destabilization by the greenhouse effect. But convective overturning kicks in, making the troposphere have the observed lapse rate. The temperature profile is NOT due to a change in pressure: example, the stratosphere, which has nearly constant temperature across 2 orders of magnitude change in pressure Roy”
***
I want to focus first on your comment that …”The temperature profile is NOT due to a change in pressure: example, the stratosphere, which has nearly constant temperature across 2 orders of magnitude change in pressure…”
Your claim that pressure has nothing to do with the temperature profile contradicts the Ideal Gas Law. Temperature and pressure are both due to the number of atoms/molecules in a certain volume of gas and as one is adjusted the other follows.
Pressure in a container is the sum of forces exerted on the walls of the container by all gas atoms/molecules. Temperature is an average of the velocities of each molecule. Heat is an unknown phenomenon we call energy, which causes the atoms/molecules to increase their velocity and increase the force with which they strike the container walls, hence the pressure.
It is obvious that pressure and temperature are correlated and interdependent on heat.
Consider the IGL…
PV = nRT
This is a long established law for a gas in physics and is a culmination of individual gas laws by scientists like Boyle, Gay Lussac, Dalton, Avogadro, etc.
It can also e written as P = pRT where small p is density and equals n/V. If we consider the atmosphere as a constant volume with a relatively constant number of molecules, then n/V is essentially a constant. Since R is the gas constant, combining constants we can write…
P = (nR/V).T
That clearly demonstrates that P and T in any gas are directly proportional provided the volume is constant and the number of molecules is constant.
I am talking here about a static atmosphere with no convection.
The fact that pressure and temperature decrease in step with altitude is proof of the above.
***
Your comparison of ocean water molecules to atmospheric gas molecules does not follow. In an ocean, the water molecules are all joined with weak hydrogen bonds and are essentially stacked on top of each other vertically. That does produce a tremendous mass, which gravity converts to a tremendous downward pressure (weight in this case).
In the atmosphere, there is no such downward force due to joined air molecules for the simple reasonthat they are not related in that manner. Each molecule is free to move upwards, downwards, or sideways. The only main pressure felt is by the surface only and that pressure is claimed to be 15 PSI at sea level.
Why does the pressure drop to 1/3rd that value by 30,000 feet altitude? Surely it cannot e claimed that rising heat via convection produces that drop in pressure. Also, why does the temperature drop proportionately?
Furthermore, why is the lapse rate the same at the North Pole in winter and at the Equator?
I seriously doubt that figure of 15 lbs/in^2 for the simple reason that a human with a head surface area of 1 square foot (144 square inches) would experience a downward force of 144 in^2 * 15 lbs/in^2 = 2160 pounds of force. Why is no one questioning that silliness?
The pundits at NASA claim we can endure such a force since the body is pushing back with an equal and opposite force. Perhaps one of them could try supporting a ton of weight and report back to us.
“human with a head surface area of 1 square foot would experience a downward force of 144 in^2 * 15 lbs/in^2 = 2160 pounds of force.”
I feel bad for Gordon’s mother, who had to deliver that giant-headed alien baby!
And he seems happy with liquid putting lots of weight on heads. But surely we would have heard more about scuba diver head implosions.
No doubt its another cover-up.
Sorry, Roy, there is just no overcoming Gordon’s determination to remain ignorant.
“Your claim that pressure has nothing to do with the temperature profile contradicts the Ideal Gas Law.”
That was not Dr. Spencer’s claim in your 1:44 am clip, Gordon. Try again, you obviously missed his point.
b4…I could have swore Roy said…’The temperature profile is NOT due to a change in pressure: example, the stratosphere, which has nearly constant temperature across 2 orders of magnitude change in pressure’.
I may be talking through my hat but the stratosphere condition is due to a very slight warming due to the absorp-tion by O2 in the stratosphere of UV, creating O3, or ozone. If not for that warming, I presume the stratosphere portion of lapse rate would continue linearly.
We have to remember that the very low pressures and temps in the stratosphere are not accurately measurable. How well would a mercury thermometer respond to temps at a tiny fraction of surface temps and barometers to a tiny fraction of surface pressures?
nate…no point feel sorry for my head when yours is so big you can get your foot in your mouth regularly.
“And he seems happy with liquid putting lots of weight on heads. But surely we would have heard more about scuba diver head implosions”.
***
Scuba divers are limited as to how deep they can go because that’s exactly what happens to a divers head if he goes too deep. Those poor souls in the mini sub diving to the Titanic found that out the hard way.
However, you could fire the same submersible into space and nothing would happen to it.
And what’s the point of sucking up to Roy when your role here as an alarmist is to undermine his good work?
“Scuba divers are limited as to how deep they can go because thats exactly what happens to a divers head if he goes too deep. ”
Evidence? No. You just make stuff up.
At 10 m under water, a diver experiences double atmospheric pressure. Obviously that is not a problem because that can go much deeper.
Why because the pressure inside their head equalizes to that outside.
And your notion that air does not have weight is obviously wrong, since evacuated containers weigh less.
A nice demo is to boil a tiny bot of water in a beer can, then turn it upside down in a bowl of cold water. The steam condenses, producing a partial vacuum, and the can gets crushed by the weight of the outside air.
Gordon,
“It can also be written as P = pRT where small p is density and equals n/V. If we consider the atmosphere as a constant volume with a relatively constant number of molecules”
Let me ask you the following:
At the altitude of commercial jet flights, > 30,000 feet, is there less atmosphere, ie lower air density?
I think we know the answer, since they choose to fly at that height to reduce drag and save fuel. And because humans need an oxygen mask at that altitude.
How bout at the altitude of low Earth satellites, > 100 km? Is there much air to create drag on their motion at that height?
I think we know the answer is that there is very very low density of atmosphere at that altitude, since such satellites are able to stay in orbit for long periods without thrust.
So we know that with increasing altitude, the density of the atmosphere decreases, significantly. The atmosphere thins.
So when you use the ideal gas law to try to find the pressure vs altitude, you need to account for this.
The density at 10 Km is about 1/3 that of the surface.
Then the pressure at 10 km is about 1/4 that at the surface.
https://www.engineeringtoolbox.com/air-altitude-pressure-d_462.html
ball4…”Gordon, you are just not capable of learning basic meteorology since adiabatic means the parcel in the 9.8C/km dT/dz earthen lapse rate derivation is NOT heated”.
***
An adiabatic process by definition means the process cannot transfer heat into or out of the process. I would like someone to explain how a theoretical column of air claimed to to be adiabatic, cannot transfer heat into and out of the column with ease. They seem to forget that heat can be transferred by air via convection very effectively.
In practice, an adiabatic process refers to a process in a container with insulated walls.
If the parcel is not heated, as you claim, then why are we talking about adiabatic processes? I just read the other day that adiabatic processes related to the lapse rate are theoretical, as they should be.
Anyway, I am not claiming the lapse rate involves heating of the air. I regard it strictly as the relationship at a specific altitude between the pressure and temperature at that altitude, and that they are related by gravitational force, not heat convected from the surface.
There are no adiabatic processes in nature, Gordon, only diabatic processes exist. To derive the ideal 9.8C/km atm. T(z) lapse rate, the parcel(z) is defined to be always the pressure & temperature of the surroundings, Ts and Ps at that z and without condensation. This definition greatly simplifies the calculation & is useful because 9.8C/km is often the actual atm. air lapse rate far from surfaces where no condensation is occurring.
“why are we talking about adiabatic processes?”
Because the significance of the defined dry adiabatic atm. air lapse rate often found at or near 9.8C/km far from surfaces with no condensation is not that it is necessarily the actual lapse rate but rather it demarcates the boundary between statically stable and unstable atmospheres which then allow for convection. Gordon can find why that is so by actually bothering to study & learn from first course meteorology.
b4…coming from someone like you who misunderstand the reality of heat or the 2nd law, your red-herring arguments about adiabatic processes is in the same category.
Roy,
You’re probably aware that the IPCC’s Seventh Assessment Report (AR7) will include a Special Report on Climate Change and Cities. I think the deadline for nominating authors has already passed, but the Expert Review of the First Order Draft will occur during Autumn 2025 if you’re interested.
I mention this in light of your ongoing work on the UHI effects, etc.
rgrds
nate…”Let me ask you the following:”
***
Nate…you are basically agreeing with me that air density decreases with altitude. What we need to ascertain is what that means with regard to heat, hence temperature, which is a relative measure of heat.
The Ideal Gas Law addresses that.
P = pRT
Where p = density = mass/volume = n/V in the IGL.
It’s telling us that with a constant mass in a constant volume pressure is directly proportional to temperature. Since temperature is a measure of heat, it tells us that heat is directly proportional to pressure.
That’s obvious. Heat is fully dependent on the number of atoms/molecules, either in a solid, a liquid or a gas.
The amount of heat in a solid is determined by…
Q = m.C.delta T
M = mass, therefore heat is directly proportional to mass. C is the specific heat which is the relative amount of heat stored by various masses.
I realize the equation above addresses the amount of heat required to raise the temperature of a mass and it means different masses require a different amount of heat to raise their temperatures an equivalent amount. However, the proportional relationship between air as a mass and specific heat stands since air has a specific heat value.
The lower the mass, the lower the amount of air the heat can hold, therefore as mass is reduced with altitude, the amount of heat the air can hold is reduced as well.
Lapse rate theory completely ignores that reality. It infers that the reduction in temperature with altitude is due to a reduction in heat from the surface when it is carried aloft by convection. That same air, which is denser at the surface, thins out into an ever-decreasing air density.
It has to since no air parcels can rise into ever-thinning air and maintain its density. It must thin as well and as it thins, it cools naturally.
Here is a far more eloquent argument by Clive Best on what is wrong with lapse rate theory.
https://clivebest.com/blog/?p=3941
“The conclusion is that you dont need convection to have a lapse rate on a planet. It is a consequence of gravity and a fixed surface temperature. Molecules high up in the atmosphere have lost average kinetic energy (temperature) rising against gravity. Molecules from the surface provide a constant re-supply of energetic molecules from the tail of a fixed temperature Maxwell Boltzmann distribution”.
I need to be clear that I am talking about an entirely static hence theoretical situation. I am fully aware that the Sun heats the surface and that the heat produced rises into the atmosphere affecting the lapse rate. Therefore my static atmosphere is significantly affected by the rising heat from the surface. Also, the Sun heats the atmosphere itself on the way in.
Still, there could be no lapse rate without gravity and the way it causes pressure to decrease with altitude. Pressure and temperature, hence heat, are closely related. You can’t have one without the other in a gas. That’s my main beef with the theory that the lapse rate is due only to rising heat from the surface.