CHAPTER 14

Urban Heat Islands, Carbon Dioxide and Global Warming

e frequently hear dire predictions about ongoing damage to our planet due to buildup of carbon dioxide resulting in global warming – allegedly due to man’s adverse influence to the environment. However, effects of “urban heat islands” on our local climate, which are demonstrably linked to mankind’s activities, represent less publicized environmental concerns.

Reviewing the available information relating to these topics, the former predictions seem to be incorrect, as this chapter will explain. However, we view the problems relating to urban heat islands with appropriate seriousness. An airport is one example of an urban heat island; a city is another example. In both examples, asphalt, buildings and concrete have predominantly replaced the natural trees and vegetation.

Urban Heat Islands

In this section, persuasive evidence suggests that the city (urban) heat island effect is a real and an ongoing cause for concern.

The term “urban heat island” (UHI) generally refers to conditions at mega-cities, like Washington, D.C., Atlanta and Phoenix. These mega-cities have displaced much of their vegetation with asphalt, buildings and concrete. Thus, a majority of their solar energy and carbon dioxide absorbing plant-life has been replaced with materials that store incoming solar radiation and then re-emit the energy as heat – mostly during nighttime – with greatest influence on MINTMP as compared to MAXTMP or AVETMP. UHI effects are reportedly also seen for cities with populations of only ten thousand.

Because airports, often located at the heart of the large cities, commonly collect weather data, any UHI effect will be reflected in their weather data. (Note: An airport weather station is identified by “AP” beside the city name in the tables of Chapters 1 through 8.)

The following examples illustrate the magnitude of the urban heat island effect, which can represent increases ranging from 0.2ºF to 2ºF per decade, or more, depending on population.

Washington, D.C. and Loudoun County, VA

Professor Michael Brewer, of George Washington University, Virginia Campus*, describes how urbanization causes a trend toward warmer temperatures and decreased summer breezes for Loudoun County. As early as 1946, downtown Washington temperatures were 5ºF to 6ºF warmer than nearby Arlington, Virginia. Records at the Dulles International Airport show that since 1963, temperatures in Loudoun County have increased by 1.5ºF. Records of average annual temperatures during several ten-year time spans were reported as:

• 53.3ºF during the 1960s,

• 53.8ºF during the 1970s,

• 54.3ºF during the 1980s,

• 54.8ºF during the eight years of record for the 1990s.

Atlanta, Georgia

Professor Brewer also cited a report by the Atlanta Constitution, namely: “the Atlanta metro area loses 50 acres of tree cover per day to make room for shopping malls, roads, and houses. Since 1973, the city has lost 341,000 acres of tree cover.” “The downtown is, on average, 6ºF to 12ºF warmer than in 1973. The suburbs show a 3ºF to 6ºF temperature increase. In addition, the summer winds tend to be weaker now than in previous years leading to additional discomfort.”

NASA’s Marshall Space Flight Center recorded as much as a 12ºF temperature difference at times between city and country. During the day, they reported that air and ground temperatures over the city were 80ºF, and 120ºF, respectively. At night, air and ground temperatures were 55ºF and 75ºF, respectively.

Phoenix, Arizona

Chain Reaction* (published by Arizona State University) reports in an interview with Professor Robert Balling, Jr., ASU Director of the Office of Climatology, that: “The average temperature in Phoenix has climbed five degrees since the 1960s. That’s due largely to the changes in surface structure that growth has brought.”

Professor Balling explains that Phoenix was once a small, farming community that irrigated heavily, but is now the eighth largest city in the United States.

He goes on to say: “Thirty or forty years ago, Phoenix’s summer nighttime temperatures often dropped into the 70s. People didn’t need air conditioners to get to sleep. But, today, night temperatures rarely drop below the mid 80s.”

To the question about whether Phoenicians are leading the global warming rush, Balling, who is a nationally recognized expert on such issues, insists “No.”

• He believes that the global warming scare is wrong. Based on review of average temperatures taken outside the big cities by Balling’s research team, the data: “… suggests that the Earth’s temperature has remained pretty much the same in recent years.” His research findings show that higher temperatures in fast-growing cities like Phoenix are caused by the heat island effect.

As an example, he contrasts the fact that Phoenix’s average temperature has risen by five degrees Fahrenheit while the temperature at Carefree, Arizona (a much more rural neighboring town) has remained unchanged. He notes that the average temperature within the entire state of Arizona has remained unchanged. He attributes this to the fact that such areas are still relatively building-free.

• The big-city heat island effect also affects rainfall patterns, because: (1) moisture is often “boiled off” from the hotter air before it can turn into rain, (2) “hot city air is also tougher and more active than cooler air,” and (3) “it is just easier for winds to go around that hot air, instead of trying to fight through it.” This is the reason why, he explains, most storms “split apart and slide to one side or another when they reach the hot central Phoenix air.” Consequently, “during summer thunderstorms, areas on the edge of Phoenix-Glendale in the west and Mesa to the east get most of the really heavy winds and rain.”

July Five-Year ISMCS Climate Comparison

To conclude this discussion about the urban heat island effect, the table below compares ISMCS long-term climate data averages for periods ending in 1990 and 1995. The comparative data show close agreement – most likely reflecting the relatively small time interval over which the data are accumulated.

	FIVE-YEAR JULY MEAN CLIMATE CHANGES

PERIOD	TIME
ENDING	INTERVAL	CITY	DEWPNT	MAXTMP	MINTMP	PRECIP

	1962 - 1990	Dulles AP	65	87	64	3.5
1990	1945 - 1990	Atlanta AP	68	88	70	5.1
	1948 - 1990	Phoenix AP	57	105	80	0.8

	1962 - 1995	Dulles AP	65	87	65	3.6
1995	1945 - 1995	Atlanta AP	68	89	70	5.3
	1948 - 1995	Phoenix AP	56	105	80	0.8

Carbon Dioxide and Global Warming

This section is a compendium of information and opinions concerning the hotly debated issues of carbon dioxide and global warming and is intended to present the viewpoint that available evidence is still insufficient to arrive at a consensus.

Because summarization of this complex information, selected by a layman, may suffer from losses of detail, eloquence and persuasion, the reader is urged to refer directly to the original writings. Much discussion in this section is derived from the following published reports, especially from the first of these (OISM):

• The Oregon Institute of Science and Medicine (OISM) *.

• The Science and Environmental Policy Project†; this Fairfax, Virginia, facility is headed by S. Fred Singer, Ph.D., astrophysicist, whose recent book‡ argues that climate science does not support the current pessimism about global warming.

• The late Professor Julian L. Simon, author of Global Warming in the Long View§ (1998), expressed his disagreement with much of the present global warming advocacy.

There is little dispute that carbon dioxide concentration in the Earth’s atmosphere has increased during the past 100 years – from about 293 ppm (parts per million) in 1900, to about 308 ppm in 1940, and to about 365 ppm at the present time.

But this current increase follows a 300-year warming trend during which time the surface and atmospheric temperatures have increased following an exceptionally cold period about 300 years ago known as the Little Ice Age.

Accordingly, the recently observed increases of carbon dioxide can be explained as due to the natural release from the oceans caused by the rising temperatures.

It is estimated that total world carbon dioxide is distributed as follows:

▪ 1.8% in the atmosphere

▪ 2.4% in the ocean surface

▪ 5.2% in vegetation, soils, and detritus, and

▪ 90.6% in the intermediate and deep oceans.

Because of uncertainties relating to the size of these reservoirs, together with uncertainties involving rates of exchange between them, there is also uncertainty in the source of the current rise in carbon dioxide.

Regardless of the source of the current carbon dioxide level, two major questions remain: (1) are elevated levels any cause for concern? and, (2) do elevated levels of carbon dioxide have anything to do with global warming? Many scientists believe that the answer to both questions is “No.”

Beneficial Effects of Carbon Dioxide

As is well known, carbon dioxide, together with sunlight, is essential for plant growth. By absorbing carbon dioxide, as well as solar rays, plants balance the ecosystem by simultaneously reducing local carbon dioxide and heat levels, and by yielding food or building materials as well as oxygen. Plant growth rates increase in proportion to increase in the level of atmospheric carbon dioxide. Moreover, increased levels of carbon dioxide tend to reduce loss of moisture through plant leaves so that plants can grow under drier conditions. Higher growth of plant life translates into higher growth of animal life.

Effect of Carbon Dioxide on Atmospheric and Surface Temperatures

Consider the following observations:

• Variations in the Earth’s temperature are thought to be due to fluctuations in solar activity. Surface temperatures in the northern hemisphere correlate exceptionally well with variations in solar activity.

• Average annual temperatures for the United States compiled by the National Climatic Data Center are now near average for the past 103 years. During this period, 1996 and 1997 are shown to have been the 42^nd and 60^th coolest years.

• In the lower troposphere (approximately 2½ miles from the Earth’s surface), carbon dioxide-induced temperature changes are expected to be similar to the surface. But, global tropospheric temperatures measured by weather balloons between 1958 and 1996 show that these temperatures are near their forty-year mean, and have been trending downward since 1979. The trend line for the period 1979 to 1996 is -0.11ºF per decade.

• Microwave sounding units also measured troposphere temperature and showed close agreement to the weather balloon data. The microwave sounding unit trend line for 1979 to 1996 is -0.08ºF per decade.

• Thus, troposphere temperatures have trended downward by about -0.09ºF per decade for the last 19 years. Global surface temperatures during this time were reported to have increased by 0.18ºF per decade. Unlike the troposphere measurements, surface measurements are influenced by the urban heat island effect.

• Looking at the last ten years, surface temperatures for the United States (in contrast to the global scene) have trended downward by -0.14ºF per decade. The corresponding weather balloon and satellite troposphere trends are

-0.73ºF and -0.54ºF per decade, respectively.

• Even though “greenhouse gases” (carbon dioxide and water) decrease the escape of terrestrial thermal infrared radiation, there is much debate about the physical distribution processes, such as horizontal movement (advection), circulation of air due to density differences (convection), and diffusion of air into the atmosphere and ocean. Without this greenhouse effect, the Earth reportedly would be about 57ºF cooler.

During the last 19 years, when atmospheric levels of carbon dioxide and water have been the highest, the troposphere temperatures have fallen. This represents a direct experimental contradiction to computer models on which forecasts of global warming are based.

A NASA climate scientist (a computer modeler supporting the United Nations Intergovernmental Panel on Climate Change) now states (contradicting one of his previous reports): “The forcings that drive long-term climate change are not known with an accuracy sufficient to define future climate changes.”

• A NASA Goddard Institute of Space Studies correlation between global surface temperature change and carbon dioxide concentration, which was widely publicized, purportedly demonstrated that atmospheric carbon dioxide [CO₂] levels adversely influence global warming. But, these surface temperature measurements reflected the well-known urban heat island effect.

Moreover, the NASA global temperature change measurements do not agree with counterpart surface temperature measurements from regions with comprehensive and high quality temperature records – nor with troposphere balloon or satellite measurements.

• Additionally, S. Fred Singer commented, “… precise Antarctic ice-core data [show] that while warmings and CO₂ increases are indeed correlated, the CO₂ increases lag the warmings by about 1,000 years. So much for the cause-effect relationship so dear to the hearts of global-warming promoters.” Professor Simon noted: “If CO₂ causes warming, it is puzzling that warming occurred before 1940 but not since then, since the greatest carbon dioxide buildup occurred after 1940.”

• Previous estimates of high sea level rise (due to glacial and polar ice melting) are now reduced from several feet to at most a few inches during this coming century. Historically, the average rate of sea level rise has been about seven inches per century for several centuries. However, there is no clear understanding about the reasons for this rise. Dr. Singer dismisses the assumption that the rise is due to either climate or human influences.

• An article in the Electronic Telegraph* (Issue 1899, August, 2000) is titled “Falling sea level upsets theory of global warming.” This new study, completed by climatologists at Tuvalu’s Meteorological Service, found that sea levels fell by nearly 2½ inches. Similar sea level falls were also recorded at Nauru and the Solomon Islands. (Tuvalu, located in the Coral Sea, was formerly part of the Gilbert and Ellice Islands.)

Forecasts of the 1990s fearfully estimated that the sea was rising by up to 1½ inches per year, and that the coral atoll of nine islands would vanish within several decades due to their low height above sea level.

• David Cristescu comments in an article “Chill, the planet’s not melting” (The New Australian, No. 133, September, 1999)†:

Does “global warming” exist? How many times have you heard that the polar caps are melting? Or that satellite photos show that they are getting smaller? Or that the caps are thinning, making it a hazardous environment for the heavy animals in the region? And how many times have you heard that this is due to “global warming?”

…

To begin with, the melting point of fresh water is 0˚C [32˚F] (slightly lower for salt water). However, the temperature at the South Pole rarely exceeds minus 20˚C [21˚F]. So any melting of the caps cannot be blamed on temperatures reaching the melting point.

• Another related article (August, 2000) appeared in News-Max.com* with title: “Readers Respond to Ice Cap Melting Story.” This article, responding to a recent New York Times article, reports that:

Robert Peary, USN, discovered the North Pole in 1909. His account of the journey, as well as of prior attempts, reveal that he had to begin the trek from northern Canada in the latter part of winter, before the sun rose above the horizon. Why? Because if he left any later, the polar ice would begin melting and would not support the weight of a man or a dog sled.

A seven-page article by Gerard Jackson “Global warming propaganda and journalistic dishonesty” (No. 160, August – September, 2000)† reports that:

The true test of any hypothesis in the physical sciences is whether it can withstand scientific scrutiny. It is now an indisputable fact that so-called global warming has failed the experimental test, the only test that counts with real scientists and not politicized media monkeys. That ignorant, self-serving politicians should engage in “global warming” grandstanding will surprise no one; that so many “journalists” however, lie to their readers about the effects of carbon dioxide concentrations on the climate and deliberately suppress scientific evidence that refutes “global warming” predictions puzzles many. It is abundantly clear that the public cannot make an informed decision on any subject unless it has been honestly apprised of the facts.

…

Why they have behaved in this manner is a question that I hope to shed some light on in the course of this article.

Growing Number of Scientists Refute Global Warming Pessimism

As reported by Candace Crandall in an opinion piece in the Washington Times (November 20, 1998)*, scientists have since voiced their dissent with the 1992 U.N. Global Climate Treaty by establishing four different petitions and accumulating more than 21,000 signatures.

The last paragraph of the article states: “Unlike Vice President Al Gore’s ‘consensus’ of 2,500 United Nations IPCC scientists, a complete fabrication, this consensus is real. There is strong opposition in the scientific community against a hasty and misguided effort by international bureaucrats to combat a problem that has yet to manifest itself. El Nino-driven odd weather is not global warming.”

Two articles in the January 14, 2001 issue of Electronic Telegraph (Issue 2060) help to dispel the establishment media’s myth of global warming:

• Scientists’ discoveries give lie to doom-monger predictions. Flooding fears were dealt a blow after a 1-year study of West Antarctic ice sheet melting have found no evidence of melting; research now suggests that sea levels will rise by no more than one millimeter per year.

• Global warming claims “based on false data”. For over a decade, faulty temperature measurements (which were used to persuade governments to curb greenhouse gases) have exaggerated the true warming rate by almost 40 percent.

Question: Is Global Warming Good or Bad

Again as reported in an opinion piece in the Washington Times (October 15, 1998)*, S. Fred Singer suggests that, overall, warming is definitely better than cooling. “It is certainly better for agriculture and therefore for basic human existence. All historical evidence shows that during the warm periods of the Middle Ages (around 1100 AD) people were better off than during the hard times of the ‘Little Ice Age’ (1450 – 1850) when crops failed and people starved.” ■

* http://www.gwuva.gwu.edu/academics/leip/heat.html.

* http://chainreaction.asu.edu/weather/island.html. Excerpted by permission from Chain Reaction Magazine Web site, ASU Research Publications.

* © 1998 by OISM. Excerpted by permission from Environmental Effects of Increased Atmospheric Carbon Dioxide, A. B. Robinson, et al., Oregon Institute of Science and Medicine, Cave Junction, OR, 1998.

‡ S. Fred Singer, Hot Talk, Cold Science: Global Warming’s Unfinished Debate, The Independent Institute, Oakland, 1998.

§ http://www.intellectualcapital.com/issues/98/0212/icbusiness.asp.

† http://newaus.com.au/news133polar.html. Excerpted by permission of The New Australian.

† http://www.newaus.com.au/aatmp160gw.html. Excerpted by permission of The New Australian.