global warming

Will global warming weaken the North American Monsoon?

Arizona gets most of its rain from thunderstorms during the summer, a period called the North American monsoon (see Arizona Monsoon for background and the anatomy of thunderstorms). By government decree, the monsoon season lasts from June 15 through September 30. In actuality, rains usually start in early July following the rain-dance ceremony of the Tohono O’odham people. In 2017, there were unusually heavy rains in July and below normal rain in August and September.

Researchers from Princeton University, using a new precipitation model, claim that global warming will decrease the rain of the monsoon. From the abstract of their paper published in Nature:

Future changes in the North American monsoon, a circulation system that brings abundant summer rains to vast areas of the North American Southwest, could have significant consequences for regional water resources. How this monsoon will change with increasing greenhouse gases, however, remains unclear, not least because coarse horizontal resolution and systematic sea-surface temperature biases limit the reliability of its numerical model simulations. Here we investigate the monsoon response to increased atmospheric carbon dioxide (CO2) concentrations using a 50-km-resolution global climate model which features a realistic representation of the monsoon climatology and its synoptic-scale variability. It is found that the monsoon response to CO2 doubling is sensitive to sea-surface temperature biases. When minimizing these biases, the model projects a robust reduction in monsoonal precipitation over the southwestern United States, contrasting with previous multi-model assessments.

Let’s see how this model premise has worked so far:

The graph below, from NOAA data, shows that year-to-year precipitation varies quit a bit. The overall trend is for increasing precipitation with global warming, not a decrease.


A plot of annual precipitation reflects the high temperatures and drought conditions of the first half of the 20th Century, but there is no apparent trend for more recent warming.

This new model, as all climate models, assumes that carbon dioxide is the major forcing of global temperature, an assumption for which there is no physical evidence.

See:

A Simple Question for Climate Alarmists

An examination of the relationship between temperature and carbon dioxide

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Why Hurricanes Can’t Be Blamed On Global Warming

The leftish press and Hollywood climate experts have been claiming that the recent rash of dangerous hurricanes is due to global warming. Dr. Roy Spencer, U.S. Science Team leader for the Advanced Microwave Scanning Radiometer flying on NASA’s Aqua satellite, takes exception to these claims in a short blog post and in a new E-bookavailable from Amazon for $2.99. The E-book is about 11,000 words long and contains 17 illustrations. I recommend you read it.

In the book, Spencer explains the origin of hurricanes and gives a history of U.S. hurricanes from colonial times to present time, including comments on hurricanes Harvey and Irma.

Spencer notes that geological studies of sediments in coastal lakes in Texas and Florida show that “catastrophic hurricane strikes were more frequent 1,000 to 2,000 years ago than in the most recent 1,000 years.” Hurricanes making landfall in Florida show a downward trend in both number and intensity (that trend includes hurricane Irma). Spencer says that hurricanes in tropical Atlantic, Caribbean, and Gulf of Mexico are not limited by sea surface temperatures.

He also notes that “ two major hurricane strikes endured by the Massachusetts Bay Colony, in 1635 and in 1675, have yet to be rivaled in more modern times.”

“…Most Atlantic hurricanes can be traced back to African easterly waves [of low wind shear].  These waves draw their energy from the temperature contrast between the hot air over the Sahara Desert and the cooler air over the Sahel, and as they leave the west coast of Africa they ‘kick start’ the organization of rain shower activity over the tropical eastern Atlantic Ocean.”

You will have to read the E-book to delve more deeply into the mechanics of hurricanes. Here is an excerpt:

If you were to go up inside the eye at the altitude where jets fly, you would find the air temperature there is 10 or 20 deg. F warmer than normal for that altitude. This warmth is caused by air being forced to sink in response to rising air in the showers and thunderstorms surrounding the eye. This ‘subsidence warming’ is a universal feature of all precipitation systems, but only in hurricanes is it highly concentrated into one relatively small area. All of the warm rising air in billowing rain clouds must be exactly matched by sinking air elsewhere, and in the case of hurricanes, that sinking air is most concentrated and intense in the eye of the storm.  For more common rain systems, the warming is much weaker as it is spread over huge areas hundreds or even thousands of miles in diameter. Only a few miles away from the eye is the heavily raining eyewall of the hurricane; this is where the strongest surface winds occur.

Spencer also has a chapter on “The Effect of Sea Level Rise on Hurricane Storm Surge” in which he shows that sea level rise has been mostly if not entirely natural, with no convincing evidence that it has accelerated from human-caused global warming.

Separate from Spencer’s data, Dr. Chris Landsea of NOAA Hurricane Research Division presents at table of Atlantic hurricanes beginning from 1851. You will see that there is no sign of influence by global warming. Landsea has this caveat about the data: “The Atlantic hurricane database (or HURDAT) extends back to 1851. However, because tropical storms and hurricanes spend much of their lifetime over the open ocean – some never hitting land – many systems were “missed” during the late 19th and early 20th Centuries (Vecchi and Knutson 2008). Starting in 1944, systematic aircraft reconnaissance was commenced for monitoring both tropical cyclones and disturbances that had the potential to develop into tropical storms and hurricanes. This did provide much improved monitoring, but still about half of the Atlantic basin was not covered (Sheets 1990). Beginning in 1966, daily satellite imagery became available at the National Hurricane Center, and thus statistics from this time forward are most complete (McAdie et al. 2009).” See data

Back in 1999, Landsea et al. published a paper which found “that multidecadal variability is more characteristic of the region. Various environmental factors including Caribbean sea level pressures and 200mb zonal winds, the stratospheric Quasi-Biennial Oscillation, the El Niño-Southern Oscillation, African West Sahel rainfall and Atlantic sea surface temperatures … show significant, concurrent relationships to the frequency, intensity and duration of Atlantic hurricanes.” (Source)

Dr. Neil Frank, former Director National Hurricane Center:

“Over the past several weeks numerous articles suggest Harvey and Irma were the result of global warming. The concept is a warmer earth will generate stronger and wetter hurricanes. A number of people have said Irma was the most intense hurricane in the history of the Atlantic while Harvey was the wettest and both were good examples of what we can expect in the future because of global warming. What does a fact check reveal about these two hurricanes?”

Frank shows that neither of the above contentions is true, read more.

See also:

Houston’s long history of flooding

Evidence that CO2 emissions do not intensify the greenhouse effect

An examination of the relationship between temperature and carbon dioxide

A Simple Question for Climate Alarmists

Trump, the National Climate Assessment report, and fake news

The New York Times recently obtained a draft of the up-coming National Climate Assessment report. NYT is worried that the Trump administration will suppress the report. However, according to scientists who worked on the report, it has been available online since last January. (See Daily Caller story) You can download the 545-page 3rd draft report here, but don’t bother.

Besides the “fake news” story in the New York Times, we have a “fake news” story from the Associated Press printed by the Arizona Daily Star. Within that story is this sentence: Contradicting Trump’s claims that climate change is a “hoax,” the draft report representing the consensus of 13 federal agencies concludes that the evidence global warming is being driven by human activities is “unambiguous.”

Definition of unambiguous: “Admitting of no doubt or misunderstanding; having only one meaning or interpretation and leading to only one conclusion.”

Because of that statement and this one: “In climate research and modeling, we should recognize that we are dealing with a coupled non-linear chaotic system, and therefore that the prediction of a specific future climate state is not possible.” — Final chapter, Draft TAR 2000 (Third Assessment Report), IPCC, I downloaded the report to see just how unambiguous the evidence is. Here is what I found.

1) All their evidence consists of computer modeling. There is no physical evidence. That’s just like the previous National Climate Assessment report. They are, in essence, claiming that evidence of warming is evidence of the cause of warming.

2) On page 139, they discuss how they attribute causes:

Detection and attribution of climate change involves assessing the causes of observed changes in the climate system through systematic comparison of climate models and observations using various statistical methods. An attributable change refers to a change in which the relative contribution of causal factors has been evaluated along with an assignment of statistical confidence.

3) Beginning on page 144, they discuss “major uncertainties.” Oops, not so “unambiguous.”

The transient climate response (TCR) is defined as the global mean surface temperature change at the time of CO2 doubling in a 1%/year CO2 transient increase experiment. The TCR of the climate system to greenhouse gas increases remains uncertain, with ranges of 0.9° to 2.0°C (1.6° to 3.6°F) and 0.9° to 2.5°C (1.6° to 4.5°F) in two recent assessments. The climate system response to aerosol forcing (direct and indirect effects combined) remains highly uncertain, because although more of the relevant processes are being in included in models, confidence in these representations remains low. Therefore, there is considerable uncertainty in quantifying the attributable warming contributions of greenhouse gases and aerosols separately. There is uncertainty in the possible levels of internal climate variability, but current estimates likely  range of +/- 0.1°C, or 0.2°F, over 60 years) would have to be too low by more than a factor or two or three for the observed trend to be explainable by internal variability.

Does that sound like the evidence is unambiguous?

“There is something fascinating about science. One gets such wholesale returns of conjecture out of such a trifling investment of fact.” – Mark Twain, Life on the Mississippi

UPDATE: The material above refers to the third draft of the report. The fifth draft has just become available. One analyst noticed “that the latest draft climate report, published in June, had seemingly left out a rather embarrassing table from the Executive Summary, one that had previously been written into the Third Draft, published last December.” What has been omitted is the fact “that the hottest temperatures, (averaged over the US), were not only much, much higher in the 1930s. They were also higher during the 1920s. Indeed there have been many other years with higher temperatures than most of the recent ones.” (Source)

I would not call it a hoax as does President Trump; I’d call it a scam. The National Climate Assessment itself is fake news; a political, rather than a scientific document.

“It is difficult to get a man to understand something, when his salary depends on his not understanding it.” – Upton Sinclair.

Additional reading:

Alan Carlin, a former senior EPA analyst, says computer models fail because: The bottom-up GCM was a bad approach from the start and should never have been paid for by the taxpayers. All that we have are computer models that were designed and then tuned to lead to the IPCC’s desired answers and have had a difficult time even doing that.

So not only are the results claiming that global temperatures are largely determined by atmospheric CO2 wrong, but the basic methodology is useless. Climate is a coupled, non-linear chaotic system, and the IPCC agrees that this is the case. It cannot be usefully modeled by using necessarily limited models which assume the opposite. Read more

Dr. Tim Ball: Uncovered: decades-old government report showing climate data was bad, unfit for purpose. In 1999, the National Academy of Sciences, the research arm of the National Research Council, released a study expressing concern about the accuracy of the data used in the debate over climate change. They said there are,

“Deficiencies in the accuracy, quality and continuity of the records,” that “place serious limitations on the confidence that can be placed in the research results.”

See also:

A Simple Question for Climate Alarmists – where is the physical evidence

Evidence that CO2 emissions do not intensify the greenhouse effect

My comments on the previous National Climate Assessment:

https://wryheat.wordpress.com/2014/11/15/national-climate-assessment-lacks-physical-evidence/

 

Pima County Az tilting at climate change

In the novel “The Ingenious Nobleman Mister Quixote of La Mancha” by Miguel de Cervantes, first published in 1605, the protagonist, Don Quixote, imagines that windmills are giants to be destroyed. Don Quixote attacks the windmills with his lance, an action called “tilting,” all to no avail. From this story comes the idiom “tilting at windmills” which means confrontations where adversaries are incorrectly perceived, or courses of action are based on misinterpreted or misapplied heroic, romantic, or idealistic justifications. We can add the motivation of political correctness to the Pima County, Arizona, plan to reduce carbon dioxide emissions.

Since President Trump has withdrawn the U.S. from the Paris Climate Accord, Pima County Supervisors have approved their own version of the Paris Accord and pledge to reduce the County’s carbon dioxide emissions.

In a previous article, “Impact of Paris climate accord and why Trump was right to dump it” I show that if all countries fully comply with their promises under the Paris Accord, it would make a difference of only 0.17°C by the year 2100.

According to an article in the Arizona Daily Star, Pima County government will attempt to cut its greenhouse-gas emissions by 42 percent from current levels by 2025, mainly by using more solar energy. The county government will attempt to get 40 percent of its electricity from very unreliable solar generation. The county will also buy 20 new electric-powered sedans for its vehicle fleet a year, at $30,000 to $40,000 apiece.

These electric vehicles are much more expensive than gasolene-powered versions of the same model. According to a new paper published in the journal Issues in Science and Technology entitled Electric Vehicles: Climate Saviors, Or Not?, driving an electric vehicle rather than a conventional petroleum-powered vehicle effectively does nothing to reduce global-scale CO2 emissions. The net carbon dioxide emissions depend greatly on how the electricity for recharge is generated.

The Star story also notes that the county government’s share of regional greenhouse gas emissions is minuscule. It generated less than 0.1 percent of all emissions produced in eastern Pima County in 2014.

In my opinion, Pima County’s action with regard to reducing carbon dioxide emissions is simply a quixotic exercise in political correctness that will have absolutely no effect on global temperature nor on Tucson temperature. The action also diverts taxpayer money from projects that would actually benefit county citizens, such as repairing roads.

“In climate research and modeling, we should recognize that we are dealing with a coupled non-linear chaotic system, and therefore that the prediction of a specific future climate state is not possible.” — Final chapter, Third Assessment Report, IPCC.

See also:

A Simple Question for Climate Alarmists which asks: “What physical evidence supports the contention that carbon dioxide emissions from burning fossil fuels are the principal cause of global warming since 1970?” Expert climate scientists can’t cite any such evidence.

Evidence that CO2 emissions do not intensify the greenhouse effect

US Summers Are Getting Much Cooler

Reblogged from Tony Hellers RealClimate Science:

https://realclimatescience.com/2017/07/us-summers-are-getting-much-cooler-2/

Every single metric shows that summer maximum temperatures are cooling in the US, and that heatwaves are becoming shorter, less intense and covering a smaller area.

Climate scientists say the exact opposite of the data, because they are consultants being paid to push the global warming scam.

A Simple Question for Climate Alarmists

What physical evidence supports the contention that carbon dioxide emissions from burning fossil fuels are the principal cause of global warming since 1970?

(Remember back in the 1970s, climate scientists and media were predicting a return to an “ice age.”)

I have posed that question to five “climate scientist” professors at the University of Arizona who claim that our carbon dioxide emissions are the principal cause of dangerous global warming. Yet, when asked the question, none could cite any supporting physical evidence.

Some of the professors would claim that computer models, when corrected for natural variation, required carbon dioxide emissions to correlate with observed warming of the late 20th Century. But computer modeling is not physical evidence; it is mere speculation. And correlation does not prove causation. One could easily substitute any increasing time series of data to produce similar results. In fact, an Australian group did a tongue-in-cheek exercise of comparing the historic price rise of a first class U.S. postage stamp with temperature. Results are shown on the graph below. The rise in the price of a stamp shows a remarkable correlation with the rise of global temperature.

In seeking an answer to the initial question, I also read the many reports from the UN Intergovernmental Panel on Climate Change. The reports provide no physical evidence, only various scenarios generated by computers. The outputs from computer models diverge widely from observational evidence because the models attribute too much warming influence to carbon dioxide emissions and too little to natural variation. (See Why Climate Models Run Hot by Rud Istvan.)

It appears that there is no physical evidence showing that carbon dioxide emissions have a significant effect on global temperature. There is, however, physical evidence showing that our carbon dioxide emissions are not having any significant effect, see my article Evidence that CO2 emissions do not intensify the greenhouse effect for details. That article examines four predictions made by climate alarmists of what we should see as atmospheric carbon dioxide content rises. In each case, what really happened was the opposite of what was predicted.

The benighted, eco-faddish, Tucson City council wants to reduce the City’s carbon footprint by installing 100 percent renewable energy for all city government operations so Tucson will not get as hot as Phoenix. (Source) If they do that, they really will be in the dark. In another article, Impact of Paris climate accord and why Trump was right to dump it, I present research which shows that even if all countries fulfilled their pledges to reduce carbon dioxide emissions made in the Paris Climate Accord, it would make a difference of only 0.17°C by the year 2100.

Can anyone provide an answer to the initial question?

Note: evidence of warming is not evidence of the cause of warming.

One other complication, Fake warming: A new peer-reviewed study finds that nearly all reported warming in the 20th century is a result of historic adjustments made to the original data. The study concludes: “The conclusive findings of this research are that the three GAST data sets [ Global Average Surface Temperature (GAST) data, produced by NOAA, NASA, and HADLEY] are not a valid representation of reality. In fact, the magnitude of their historical data adjustments, that removed their cyclical temperature patterns, are totally inconsistent with published and credible U.S. and other temperature data. Thus, it is impossible to conclude from the three published GAST data sets that recent years have been the warmest ever –despite current claims of record setting warming.” Read the study

Bottom line: Reducing carbon dioxide emissions will have little, if any, effect on global temperature. Such efforts are therefore a waste of money and other resources.

See also:

An examination of the relationship between temperature and carbon dioxide

Carbon dioxide is necessary for life on Earth

What keeps Earth warm – the greenhouse effect or something else?

Satellite data show that CO2 has almost no effect on global warming

Geology is responsible for some phenomena blamed on global warming

The past is getting cooler – an example of fake warming

 

 

Impact of Paris Climate Accord and why Trump was right to dump it

The much touted Paris Climate Accord aims at worldwide reduction of carbon dioxide emissions in order to keep global temperatures from rising more than 2°C above pre-industrial levels. This goal is purely arbitrary and based not upon any physical evidence, but upon the unproven assumption that carbon dioxide emissions play a significant role in global warming. What the Paris Accord really does is to transfer trillions of dollars from industrialized countries, mainly the US, to the sticky-fingered United Nations and to developing nations. It has a very minimal effect on global warming.

Several studies estimate the actual effects of the Accord. The most recent is from Bjorn Lomborg, published in the peer-reviewed journal, Global Policy (read full paper). Here is the paper abstract:

This article investigates the temperature reduction impact of major climate policy proposals implemented by 2030, using the standard MAGICC climate model [developed at the National Center for Atmospheric Research, Boulder, US, and University of Adelaide, Australia].

Even optimistically assuming that promised emission cuts are maintained throughout the century, the impacts are generally small.

The impact of the US Clean Power Plan (USCPP) is a reduction in temperature rise by 0.013°C by 2100.

The full US promise for the COP21 climate conference in Paris, its so-called Intended Nationally Determined Contribution (INDC) will reduce temperature rise by 0.031°C.

The EU 20-20 policy has an impact of 0.026°C, the EU INDC 0.053°C, and China INDC 0.048°C.

All climate policies by the US, China, the EU and the rest of the world, implemented from the early 2000s to 2030 and sustained through the century will likely reduce global temperature rise about 0.17°C in 2100.

The estimated cost of this scam:

REPORT: $12.7 Trillion Needed To Meet Paris Climate Accord’s Goal

by Michael Bastasch, Daily Caller

A whopping $7.4 trillion will be spent globally on new green energy facilities in the coming decades, but another $5.3 trillion is needed to meet the goals of the Paris climate accord, according to a new report.

Bloomberg New Energy Finance (BNEF) is out with a new long-term energy outlook report, this time projecting a total of $12.7 trillion to keep projected global warming below 2 degrees Celsius by the end of the century — a goal of the Paris accord. Read more

“The current focus on CO2 emissions reductions risks having a massively expensive global solution that is more damaging to societies than the problem of climate change.” – Dr. Judith Curry

But the Accord will harm poor people in developing countries:

While the plan’s costs may range as high as $1 trillion annually, none of it would have any meaningful impact on the roughly three billion people in the developing world who currently have no real access to energy.

Much of the developing world still burns dung as their chief means of cooking and heating. Realistically, the most effective means of saving their lives and improving living conditions would be to provide the steady electricity generation needed for water and sewage treatment as well as lighting and cooking.

The Paris Accord, in contrast, essentially ends any chance to help them. While natural gas and coal power plants could provide reliable, affordable electricity for these populations, the Accord aims to steadily reduce fossil fuel usage. Read more

Estimates of the Accord’s effectiveness in reducing global warming as stated above are based on analysis of surface temperatures. However, “For the past 38 years, satellites have continually tracked global temperatures. And what they’ve recorded in that time is a temperature increase averaging 0.136 degrees Celsius per decade. That means on its current trajectory the Earth could see a potential surface temperature increase of 1.36 degrees Celsius over the entire 21st century.

Noting the current warming trajectory, it appears that by simply doing nothing, the world could accomplish the main goal of the Accord.” (IBID.)

See also:

Evidence that CO2 emissions do not intensify the greenhouse effect

Failure of climate models shows that carbon dioxide does not drive global temperature

An examination of the relationship between temperature and carbon dioxide

 

An examination of the relationship between temperature and carbon dioxide

Natural variation trumps CO2

Many climate scientists claim that our carbon dioxide emissions are the principal driver of global warming. I have asked several University of Arizona professors, who make such a claim, to provide supporting physical evidence. So far, none have been able to justify the claim with physical evidence.

In this article, we will examine the Earth’s temperature and the carbon dioxide (CO2) content of the atmosphere at several time scales to see if there is any relationship. I stipulate that the greenhouse effect does exist. I maintain, however, that the ability of CO2 emissions to cause global warming is tiny and overwhelmed by natural forces. The main effect of our “greenhouse” is to slow cooling.

There is an axiom in science which says: “correlation does not prove causation.” Correlation, however, is very suggestive of a relationship. Conversely, lack of correlation proves that there is no cause-and-effect relationship.

Phanerozoic time – the past 500 million years:

 

Estimates of global temperature and atmospheric CO2 content based on geological and isotope evidence show little correlation between the two. Earth experienced a major ice age in the Ordovician Period when atmospheric CO2 was 4,000ppm, 10 times higher than now. Temperatures during the Cretaceous Period were rising and steamy, but atmospheric CO2 was declining.

Notice also, that for most of the time, Earth’s temperature was much warmer than now and life flourished. There were some major extinction periods, all associated with ice ages.

Sources:

Berner, R.A. and Kothavala, Z, 2001, GEOCARB III: A Revised Model of Atmospheric CO2 over Phanerozoic Time, American Journal of Science, Vol. 301, February, 2001, P. 182–204

Scotese, C.R., http://www.geocraft.com/WVFossils/Carboniferous_climate.html

Our current ice age – the past 420,000 years:

During the latter part of our current ice age, glacial-interglacial cycles occurred with a periodicity of about 100,000 years which correlates with the changes in Earth’s orbit around the sun as it changes from nearly circular to elliptical with an eccentricity of about 9%. Here we see an apparent correlation between temperature and CO2. The data are from ice cores collected at the Vostok station in Antarctica. The scientists working on the Vostok core noticed that temperature changes PRECEDED changes in CO2 concentration by about 800 years. Again, we see that CO2 doesn’t have much influence on temperature, but temperature has great influence on CO2concentration because temperature controls CO2 solubility in the ocean.

Sources:

Petit, J.R., et al., 1999. Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica. Nature 399: 429-436.

Mudelsee, M, 2001. The phase relations among atmospheric CO2 content, temperature and global ice volume over the past 420 ka, Quaternary Science Reviews 20:583-589.

Siegenthaler, U. Et al., 2005. Stable carbon cycle-climate relationship during the late Pleistocene. Science 310: 1313-1317.

The Holocene – the past 10,000 years:

The Holocene represents the current interglacial period. For most of the past 10,000 years, temperature was higher than now. CO2 was fairly steady below 300ppm (vs over 400ppm now). There were cycles of warm and cool periods at a periodicity of 1200 to 1500 years. This periodicity correlates with the interplay of the several solar cycles. The sun itself goes through cycles of solar intensity and magnetic flux. When the cycles are in a strong phase, the amount of cosmic rays entering the atmosphere is reduced, there are fewer clouds to block the sun, so it is warmer. When solar cycles wane, as is beginning to happen now, more cosmic rays enter the atmosphere and produce more clouds which block the sun, so it becomes cooler. The number of sunspots (hence magnetic flux) varies on an average cycle of 11 years. There are also 87-year (Gliessberg) and 210-year (DeVriess-Suess) cycles in the amplitude of the 11-year sunspot cycle which combine to form an approximately 1,500-year cycle of warming and cooling.

The 20th Century:

 

The first part of the 20th Century experienced warming in the 1920s and 1930s comparable to current temperatures. According to NASA, atmospheric CO2 rose from 295ppm in 1900 to 311ppm in 1940. Major emissions from burning fossil fuels, however, commenced after WWII in the mid 1940s. The period 1940-1970 saw a CO2 rise of 311ppm to 325ppm. That period also showed global cooling to such an extent that climate scientists were predicting a return to glacial conditions. From about 1980 to 2000, CO2 rose from 339ppm to 370ppm and we had warming during that period until the super El Nino of 1997/1998. Some of this data has been “corrected” by NOAA.

Source: NOAA Climate at a glance

The 21st Century so far 

Microwave data from satellites converted to temperature.

Between the El Nino of 1997 and that of 2016, there have been temperature fluctuations but no net warming. Atmospheric CO2 rose from 363ppm to 407ppm today. It seems that there is no correlation between global temperature and CO2.

As I said at the beginning, while the CO2-induced greenhouse effect has some hypothetical warming potential, that warming is tiny and overwhelmed by the forces of natural variation. So far, I have seen no physical evidence to contradict my contention.

Source : http://www.drroyspencer.com/2017/05/uah-global-temperature-update-for-april-2017-0-27-deg-c/

See also: Evidence that CO2 emissions do not intensify the greenhouse effect

More March Madness – AZ Star blames human-caused climate change for March heat

On Sunday, April 30, the Arizona Daily Star published a front-page story by Tony Davis which proclaimed “Greenhouse gases called a factor in March heat.” (Link to online version)

The story begins: “Human-caused climate change was at least partly to blame and probably mostly to blame for Tucson’s record-setting March heat, says a researcher with expertise in this field.”

This story is another example of speculation based on computer modeling and cherry-picked data rather than physical evidence. The Star consulted Dr. Geert Jan van Oldenborgh of the Royal Netherlands Meteorological Institute who analyzed possible factors for explaining Tucson’s March temperatures. “He concluded that long-term temperature trends point almost certainly to human-caused greenhouse-gas emissions as a factor. The unresolved question, he said, is how big of a factor they are.” The article provides no physical evidence to support that conclusion.

Ignoring the high temperatures during the 1900s to 1930s, van Oldenborgh examined the record beginning in 1950 and found “a clear upward trend in the March high temperatures started in the middle 1970s.” (See my article: March 2017 – Hottest Ever in Tucson? for earlier temperature data. That article shows Tucson’s temperatures steadily rising, probably due to the urban heat-island effect, while temperatures in rural Tombstone remained level.)

From the Star: “Looking across Southern and Central Arizona high temperatures for March, van Oldenborgh found they seem to be warming across the region but that Tucson’s temperatures are rising faster than in nearby cities Casa Grande and Willcox.”

“The urban heat-island effect often accounts for differing temperatures between larger and smaller cities. But van Oldenborgh said he tried to account for such differences by focusing his analysis on daytime high temperatures, not nighttime lows that are most commonly affected by the heat island effect.” So he didn’t study the heat island effect.

Oldenborgh looked at computer models. One model set “showed that March high temperatures have risen at a point near Tucson at about 2.5 times the rate the global average temperature has risen since about 1950. The model shows that is the local effect of global warming.” (A new term: local global warming?) The other model set “showed that Tucson has received on average less long-term warming than shown by the first model.”

The article contained much “expert” speculation, but from the material presented, I see no physical evidence justifying the conclusion nor the headlines that could attribute the high March temperatures to carbon dioxide emissions. If it was not just a quirk of natural variation, then maybe Tucson has its own evil cloud of carbon dioxide hovering above the city. Of course, there was lots of hot air expelled by local politicians in March.

In my opinion, this type of story is, to put it politely, junk science, designed to stir up alarm about a subject that has become purely political. It is not really news, but propaganda.

Here is the temperature record from the USHCN weather station at the University of Arizona. The top red line shows March high temperatures. The other lines show a slow rise consistent with the urban heat island effect. Had van Oldenborgh used this more complete record, his “clear upward trend” would have disappeared.

See also:

Evidence that CO2 emissions do not intensify the greenhouse effect

Also look at this story from 2012: MILD WINTER MAKES MARCH MADNESS