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Thursday, December 1, 1988 / University Daily Kansan
Science
Global warming: Is it a trend that's here to stay or is it just a fluke of nature?
The greenhouse effect refers to global warming. As sunlight reaches the Earth's atmosphere, some light is reflected by clouds and ice, but most is absorbed by the Earth, creating heat, or infrared energy. Although the heat is usually re-radiated into space, sometimes it strikes molecules of carbon dioxide and other gases, and the heat is reflected back to Earth. The more carbon dioxide and other greenhouse gases in the atmosphere, the more the Earth's temperature increases. The greenhouse effect occurs naturally to an extent, but it is intensified by activities of man.
By Cindy Harger Kansan staff writer
Soaring temperatures and harsh drought conditions this summer have left scientists pondering the future of the Earth.
Many think that it was merely a periodic heat wave, but others fear it could have been a preview of global warming due to the greenhouse effect.
As sunlight reaches the Earth's atmosphere, some light is reflected by clouds and ice, but most is absorbed by the Earth, creating heat, or infrared heat. The heat usually is re-radiated into space. However, sometimes it strikes molecules of carbon dioxide and other gases, and the heat is reflected back to Earth. The more carbon dioxide and the more greenhouse gases in the atmosphere, the more the Earth's temperature increases.
Greenhouse gases, those gases that add to global warming, are produced by industry, transportation, deforestation and farming. The greenhouse effect occurs naturally to an extent, but it is intensified by these activities.
"Most scientists believe that human intervention in the greenhouse effect is real," said Glen Maret, professor of meteorology. "Some believe that droughts this summer directly wge related to the greenhouse effect."
But Marotz said that wasn't necessarily so. In the 1930s, the United States experienced a drought that lasted much longer and was much worse, and that drought didn't necessarily signal global warming.
"The atmosphere is always going to do this," he said. "Most people would say there is not good evidence at this point to say that this summer's heat wave and drought was due to the greenhouse effect."
James Hansen, director of the NASA Goddard Institute for Space Studies in New York City, thinks there is enough evidence to link summer temperatures to global warming.
warning.
On June 23, Hansen told the U.S. Senate Committee on Energy and Natural Resources that the summer heat was only a preview of the greenhouse effect. He said that the Earth was warmer in 1988 than at any other time in the history of instrumental research.
"In my opinion, the greenhouse effect has been detected, and it is changing our climate now." Hansen told the Senate committee. "Altogether, the evidence that the Earth is warming by an amount which is too large to be a chance fluctuation and the similarity of the warming to that expected from the greenhouse effect represents a very strong case."
Marotz said that most worries stemmed from observations showing that carbon dioxide was steadily increasing in the atmosphere. Carbon dioxide increases the
greenhouse effect and the Earth's temperature along with it.
Carbon dioxide is produced mainly during the burning of fossil fuels such as coal, oil and gas. Deforestation in the tropics, such as recent forest burning in the Amazon jungle in Brazil, also contributes to the amount of carbon dioxide in the atmosphere.
"The temperature has risen 1 degree Celsius, which is almost 2 degrees Fahrenheit, over the last 100 years." Marotz said. "Projections suggest the atmosphere may heat up another 2 degrees Celsius, or even 4 or 5. That is really significant."
That increase would equal the rise in temperature since the end of the last ice age.
"If the predicted change occurs, then there would be some real changes in the way the atmosphere operates," Marotz said.
Some scientists predict that if greenhouse gases keep accumulating at the present rate, drastic changes would occur by the middle of the next century. The temperature increase would cause weather-pattern changes, which could bring drought to previously fertile areas and flooding in deserts.
Ocean levels would rise because the heated water would expand and glaciers would melt, and some islands and lower coastal areas would be swamped.
Hansen said at this summer's Senate committee hearing that his predictions showed greater-than-average warming in the midwest in the late 1800s and 1900s.
we conclude that there is evidence that the greenhouse effect increases the likelihood of heat wave drought situations in the southeast and midwest United States, especially where a specific drought on the greenhouse effect," he said.
However, some scientists say Hansen's conclusion is jumping the gun. Joe Eagleman, professor of meteorology, physics and astronomy, said that more information scientists could say that the warming trend had started
"People who have gotten excited about the greenhouse effect are only looking at measurements showing CO2 (carbon dioxide) levels increasing." Eagleton said. "If an increase in CO2 levels is going to cause warming, you need to measure what the change is, but you also need to correct for temperature cycles and the heat-island
He said that with the heat-island effect temperatures in cities were higher than in the country because of pollution and surface materials such as concrete. Temperature measurements taken in a city could reflect the city's growth and aren't necessarily representative of global warming trends.
Eagleman said there also were changes in other measurements that would counter-balance that warming effect. Levels of cloud-cover measurements and fine-particle air have increased. Those factors would cause cooling.
factors whose cause cooling.
Even though he hadn't concluded that recent heat waves were caused by the greenhouse effect, Marotz said that he wasn't denying that the greenhouse effect was valid. However, there was little man would do to decrease the effects.
Rill Skeat/KANSAN
"We're caught in a bind," he said. "The answer is to stop burning fuels, and we can't do that."
"We can change from fossil fuel to a solar economy, but you have to buy solar heaters, which would have to be made by burning fossil fuels."
Maroet said we would have to make changes that weren't economically feasible.
"I don't think there's hope about doing anything unless the world as a whole makes a change," he said. "But Third World people can't afford to buy solar heaters."
Most scientists say that the greenhouse effect could be minimized by conserving energy, by using less coal and exploring other energy possibilities such as nuclear, geothermal and solar energy.
Reducing the warming rate
Report outlines states' role in battling greenhouse effect
By Cindy Harger
Kansas staff writer
States, including Kansas, have an important role in minimizing the greenhouse effect, an environmental group said in a report released earlier this month.
Renew America, a Washington, D.C., based organization released the report, called "Reducing the Rate of Global Warming." The States Role" on Aug. 12, the report said, national states, in addition to the federal government, can take steps to reduce the greenhouse effect.
"States can initiate action and provide models of effective programs, but a strong federal presence is required to ensure that all states implement effective policies," the report stated.
"What is needed is a fundamental transformation of our energy system," said Tina Hobson, executive director of Renew America. "The keys to reducing our use of fossil fuels are to make major, across-the-board improvements in energy efficiency and move toward an energy system based on solar and other
report stated.
The term "greenhouse effect" refers to the warming of the earth from a blanket of gases, mostly carbon dioxide, that have accumulated in the atmosphere. The gases trap the sun's heat, causing the earth to heat up.
According to the report, the United States is the single largest contributor to the atmospheric build-up of carbon dioxide. With only 5 percent of the world's population, the United States is responsible for about 20 percent of the global greenhouse effect.
renewable energy resources."
The report gives a state-by-state breakdown of carbon dioxide emissions from burning coal, oil and natural gas. Carbon dioxide accounts for about 50 percent of the gases that contribute to the greenhouse effect
According to the report, Kansas ranked 23rd in the amount of carbon emissions from fossil fuels in 1986. It ranked 18.2 million metric tons of carbon.
That compares to Texas, which was No. 1 in the rankings with 154.87 million metric tons of carbon emissions, and Vermont, which had the least, with 1.31 metric tons.
the report stated that electric power plants in Kansas contributed about 33 percent of the state's carbon emissions. Kansas ranked 24th in the country in that category. Transportation emissions in Kansas contributed 27 percent of emissions, ranking Kansas at 32nd in the country.
The report also suggested policies and programs for states that could help reduce the build-up of gases. According to the report, states should promote energy efficiency and renewal of infrastructure security and transportation. States also should promote reforestation, the report said.
Contributors to The Greenhouse Effect
The following gases are the major contributors to The Greenhouse Earth. Carbon Dioxide, Methane, CFCs, and Nitrous Oxide are all long-lived and mix well in the atmosphere, so their concentrations can be measured more accurately. However, the "other" category is much harder to measure because of its short life and varying concentrations from one area to another.
Theory suggests sun cycling
Source: Journal of Geophysical Research
By Cindy Harger
Kesson staff writer
The sun's rays still in the sky. Although it's still in the sky, some scientists think that the sun's fire may be burning low.
If the sun is indeed dwindling, the greenhouse effect actually could benefit the earth, said Edward Zeller, professor of physics and astronomy and director of the Radiation Physics Laboratory in the Space Technology Center at the University of Kansas.
the greenhouse effect is global warming caused by above-average concentrations of gases in the atmosphere. The gases, which are added to by industry, deforestation, transportation, and energy, trap heat from the sun, causing the earth to heat up.
"We may be polluting ourselves out of serious trouble," he said.
A gradual cool-down
And so will the sun. Zeller said that even if the core was not burning, the Earth still could be receivable from the outer surfaces of the sun.
Zeller explained the theory of the waning sun by comparing the sun to a saddle. Shortly after it runs out, the water will still generate some heat.
Zeller has based his theory on studies he has done in Antarctica. The layers of ice in Antarctica contain natural records of sun activity that date back thousands of years. By measuring changes in nutrinos from one layer of ice to another, Zeller has been able to guess what is happening in the sun's core. Nutrinos are particles that are released from the sun's core as nuclear fusion occurs.
"I'm saying the furnace is still hot, but the fire is very low or out all together." Zeller said.
"We've been measuring these for several years and have found them to be very low." Zeller said "We've found about one-third to one-fifth of the nutrinos expected."
He also said that charted temperature averages show a decrease in global temperatures, not an increase as the greener net would suggest. Average local temperatures also are dropping.
The apparent decrease in the sun's activity could be part of a natural cycle, Zeller said. It may indicate a trend toward another age tag. In that respect the greenhouse would postpone temperature drops.
"We know that over the past 2 million years, the earth has gone through wild temperature gyrations," he said. "The normal condition is not what we have now, but much colder."
Deforestation
Zeller said that the earth has had
The possibility exists that the sun is cycling on and off," Zeller said. "It's a concept many of my colleagues wouldn't agree with, but it may be true. We think of the moon as constantly moving, but really how constant is it?"
Raymond Arritt, assistant professor of physics and astronomy, said that in the early half of the 20th Century, it was unusually warm and that is what people think of as normal temperatures.
about six glacial periods that last from 80,000 to 100,000 years. However, the warmer periods usually last only 10,000 to 15,000 years.
"It's interesting that back during the 70s, there was a fear of going into an ice age," Arritt said. "Zeller's theory is based on what seems to be an established trend of two (the earth's) cooling and the greenhouse effect) would balance out."
Trees and plants along with humans and animals naturally recycle carbon dioxide and oxygen. This balanced $ \mathrm{CO}_{2} $ -oxygen cycle maintains the air and climate that is needed to sustain life.
The rapid destruction of tropical forests is endangering the balance of this cycle.
inside the air sacs, oxygen and CO<sub>2</sub> are separated from the air. The oxygen in the blood is carried in a membrane and enters red blood cells. In tiny blood vessels, there are no air sacs.
The CO<sub>2</sub> is expelled from our bodies when we exhale.