Posts tagged technology
CU study: We’re not so different than the Ancients
Feb 12th
rules of development, says CU-Boulder researcher
Recently derived equations that describe development patterns in modern urban areas appear to work equally well to describe ancient cities settled thousands of years ago, according to a new study led by a researcher at the University of Colorado Boulder.
“This study suggests that there is a level at which every human society is actually very similar,” said Scott Ortman, assistant professor of anthropology at CU-Boulder and lead author of the study published in the journal PLOS ONE. “This awareness helps break down the barriers between the past and present and allows us to view contemporary cities as lying on a continuum of all human settlements in time and place.”
Over the last several years, Ortman’s colleagues at the Santa Fe Institute (SFI), including Professor Luis Bettencourt, a co-author of the study, have developed mathematical models that describe how modern cities change as their populations grow. For example, scientists know that as a population increases, its settlement area becomes denser, while infrastructure needs per capita decrease and economic production per capita rises.
Ortman noticed that the variables used in these equations, such as cost of moving around, the size of the settled area, the population, and the benefits of people interacting, did not depend on any particular modern technology.
“I realized that if these models are adequate for explaining what’s going on in contemporary cities, they should apply to any settlements in any society,” he said. “So if these models are on the right track, they should apply to ancient societies too.”
To test his idea, Ortman used data that had been collected in the 1960s about 1,500 settlements in central Mexico that spanned from 1,150 years B.C. through the Aztec period, which ended about 500 years ago. The data included the number of dwellings the archaeologists were able to identify, the total settled area and the density of pottery fragments scattered on the surface. Taken together, these artifacts give an indication of the total population numbers and settlement density of the ancient sites.
“We started analyzing the data in the ways we were thinking about with modern cities, and it showed that the models worked,” Ortman said.
The discovery that ancient and modern settlements may develop in similar and predictable ways has implications both for archaeologists and people studying today’s urban areas. For example, it’s common for archaeologists to assume that population density is constant, no matter how large the settlement area, when estimating the population of ancient cities. The new equations could offer a way for archaeologists to get a more accurate head count, by incorporating the idea that population density tends to grow as total area increases.
In the future, the equations may also guide archaeologists in getting an idea of what they’re likely to find within a given settlement based on its size, such as the miles of roads and pathways. The equations could also guide expectations about the number of different activities that took place in a settlement and the division of labor.
“There should be a relationship between the population of settlements and the productivity of labor,” Ortman said. “So, for example, we would expect larger social networks to be able to produce more public monuments per capita than smaller settlements.”
The findings of the new study may also be useful to studies of modern societies. Because ancient settlements were typically less complex than today’s cities, they offer a simple “model system” for testing the equations devised to explain modern cities.
“The archaeological record actually provides surprisingly clear tests of these models, and in some cases it’s actually much harder to collect comparable data from contemporary cities,” Ortman said.
Other co-authors of the study include Andrew Cabaniss of Santa Fe Institute and the University of North Carolina Chapel Hill and Jennie Sturm of the University of New Mexico.
The study is available at http://dx.plos.org/10.1371/journal.pone.0087902.
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CU: Gas-fired plants help clean the air
Jan 10th
Power plants that use natural gas and a new technology to squeeze more energy from the fuel release far less of the greenhouse gas carbon dioxide than coal-fired power plants do, according to a new analysis accepted for publication Jan. 8 in Earth’s Future, a journal of the American Geophysical Union. The so-called “combined cycle” natural gas power plants also release significantly less nitrogen oxides and sulfur dioxide, which can worsen air quality.
“Since more and more of our electricity is coming from these cleaner power plants, emissions from the power sector are lower by 20, 30 even 40 percent for some gases since 1997,” said lead author Joost de Gouw, an atmospheric scientist with NOAA’s Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado Boulder. NOAA is the National Oceanic and Atmospheric Administration.
De Gouw, who works at NOAA’s Earth System Research Laboratory (ESRL), and his NOAA and CIRES colleagues analyzed data from systems that continuously monitor emissions at power plant stacks around the country. Previous aircraft-based studies have shown these stack measurements are accurate for carbon dioxide (CO2) and for nitrogen oxides and sulfur dioxide. Nitrogen oxides and sulfur dioxide can react in the atmosphere to form tiny particles and ozone, which can cause respiratory disease.
To compare pollutant emissions from different types of power plants, the scientists calculated emissions per unit of energy produced, for all data available between 1997 and 2012. During that period of time, on average:
- Coal-based power plants emitted 915 grams (32 ounces) of CO2 per kilowatt hour of energy produced;
- Natural gas power plants emitted 549 grams (19 ounces) CO2 per kilowatt hour; and
- Combined cycle natural gas plants emitted 436 grams (15 ounces) CO2 per kilowatt hour.
In combined cycle natural gas plants, operators use two heat engines in tandem to convert a higher fraction of heat into electrical energy. For context, U.S. households consumed 11,280 kilowatt hours of energy, on average, in 2011, according to the U.S. Energy Information Agency. This amounts to 11.4 metric tons per year of CO2 per household, if all of that electricity were generated by a coal power plant, or 5.4 metric tons if it all came from a natural gas power plant with combined cycle technology.
The researchers reported that between 1997 and 2012, the fraction of electric energy in the United States produced from coal gradually decreased from 83 percent to 59, and the fraction of energy from combined cycle natural gas plants rose from none to 34 percent.
That shift in the energy industry meant that power plants, overall, sent 23 percent less CO2 into the atmosphere last year than they would have, had coal been providing about the same fraction of electric power as in 1997, de Gouw said. The switch led to even greater reductions in the power sector’s emissions of nitrogen oxides and sulfur dioxide, which dropped by 40 percent and 44 percent, respectively.
The new findings are consistent with recent reports from the Energy Information Agency that substituting natural gas for coal in power generation helped lower power-related carbon dioxide emissions in 2012.
The authors noted that the new analysis is limited to pollutants emitted during energy production and measured at stacks. The paper did not address levels of greenhouse gases and other pollutants that leak into the atmosphere during fuel extraction, for example. To investigate the total atmospheric consequences of shifting energy use, scientists need to continue collecting data from all aspects of energy exploration, production and use, the authors concluded.
Authors of the new paper, “Reduced Emissions of CO2, NOx and SO2 from U.S. Power Plants Due to the Switch from Coal to Natural Gas with Combined Cycle Technology,” are de Gouw (CIRES), David Parrish (NOAA ESRL), Greg Frost (CIRES) and Michael Trainer (NOAA).
CIRES is a joint institute of NOAA and CU-Boulder.
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Obituary: George Washington Hunt “Buzz” 1938-2013
Dec 24th
Mr. Hunt did lots of personal research in religions and sciences, and through the years became very involved with uncovering details of corruption and possible conspiracies in the banking industry. He was devoted to bring this knowledge to people in effort to enlighten as many ears as he could. He created an informational website called www.TheBigBadBank.com where he hosted many videos and stories about his sociological findings in his focused interests in conservation, economic and technology industries.
George was a very charitable and friendly person and always helped those in need and made many friends through doing so.
ed note: We at Boulder Channel 1 were graced with his presence through helping him with creating his website and producing his videos which he will continue to distribute after his passing through his website and social media outlets. May his soul rest in peace.