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The Long Summer
New science museum in the nations capital
New maps from the U.S. Geological Survey
The Long Summer: How Climate Changed
Climate and humanity are dancing. The global weather system is leading our
developing species across the parquet, serving as both band and dancer. In response
to each mercurial change in tempo, its human partner must innovate new moves
or migrate to a new part of the dance floor. Evidence of the dance is left behind
in climatic proxies such as tree rings, pollen grains and deep cores of glacial
ice, as well as artifacts like grain baskets, cave paintings and Clovis spear
In The Long Summer: How Climate Changed Civilization, Brain Fagan describes this climatic dance and the immense role it plays in shaping the development of human civilization. Fagan says that when the weather shifts, people react, and history is writ. A professor emeritus of anthropology at the University of California, Santa Barbara, Fagan synthesizes the work of dozens of scientists in piecing together a climatic waltz through time.
Fagans story begins at the conclusion of the last ice age: the beginning of the titular long summer in which civilization arose. Fagan describes the tundra landscape of Europe as breathing. When weather is warmer, animals and humans flood in. When the climate turns colder, they are exhaled to the south.
This warming contributed to the extinction of a majority of the planets megafauna and a transition to more sedentary societies. By no means was this an instantaneous process: The pyramids of Giza were being constructed while mammoths were still living in Siberia.
Synthesizing work by Steve Hostetler, Wallace Broecker and Jim Teller, Fagan argues that Mesopotamian humans became agriculturists in response to the draining of glacial Lake Agassiz in North America. Warming climate caused the lakes ice dam to breach, emptying the enormous reservoir. Without the moderating influence of this northerly body of freshwater, climatic shifts caused an Atlantic conveyor shutdown, provoking the Younger Dryas cooling event. In Mesopotamia, this meant that traditional food supplies began to vanish. People turned to agriculture as a means of surviving this transition, but by the time the Atlantic began circulating again, farming had become a habit too engrained to break.
Similarly profound, Fagan presents an account based on William Ryan and Walter Pitmans theory of the flooding of freshwater Euxine Lake (the ancestral Black Sea) by the salty Mediterranean in 5,600 B.C. Over two years, the waters rose as much as 15 centimeters per day, an event credited with causing a mass exodus from the region, thereby populating much of Europe and the Near East, as well as being the source of the biblical flood story (see Geotimes, February 2004).
Fagan postulates climatic determinants for many trends in human society. Drawing on studies by Harvey Weiss, Joy McCorriston, Frank Hole and Samuel Kramer, he makes the argument that irrigation caused the development of urban communities. One chapter describes the influence of El Niño events on the course of history. Another chapter describes how the competition for European dominance between Celts and Romans was largely decided by the position of the transition between Mediterranean and temperate habitats. As that line shifted, so did the fortunes of empires. There is also a fascinating exposition on the unlikely development of cattle herding culture in the Sahara. And, with David Hodells Caribbean gypsum-calcite ratios to back him up, Fagan pins the collapse of Mayan civilization on cyclical droughts.
In describing the various lines of research, Fagan does well at providing portraits of the motives and personalities of some of the scientists involved. One of the most notable examples is the archaeologist Alfred Rust, who bicycled from Syria to Germany after his funding ran out.
Fagan has visited many of the archaeological sites that tell the human side of this tightly interwoven dance for two. However, his travelogues are often the weakest part of the book, as the anecdotes sometimes smack of melodrama. He opens the book on a dark and stormy night, for instance, where he is self-rendered as a stalwart adventurer caught in an ocean tempest. He redeems himself in another chapter with a tender and reverent description of the cave paintings at Niaux in France.
The book ends with a caution: Fagan argues that historys larger trend is that we buffer ourselves against the short-term vicissitudes of meteorology only to make ourselves susceptible to longer-term climate variation. The whole course of civilization may be seen as a process of trading up on the scale of vulnerability, Fagan writes. In addition to the unlucky civilizations profiled in The Long Summer, this has implications for all of modern society.
Written for a broad audience, the book contains more whiz bang than the average climatologic journal article. It is a reasonably easy read, with enough scientific details to whet the geologic appetite.
New science museum in the nations capital
|The Marian Koshland Science Museum is open every day but Tuesday from 10 a.m. to 5 p.m. It is located at 6th and E Streets, NW, in downtown Washington, D.C. Admission is $5 for adults and $3 for seniors and students.|
In Washington, D.C., a city chock-full of world-class exhibitions, yet another
museum entered the scene this spring. The new, state-of-the-art Marian Koshland
Science Museum, sponsored and run by the National Academy of Sciences (NAS),
offers the high-level scientific information contained in NAS reports to the
public through captivating interactive exhibits.
NAS produces several hundred highly technical scientific reports each year, ranging in topic from global warming and environmental considerations to medicine, genetics and engineering. Many of the scientists who are involved in the reports are also involved in the museum. The museums creators combed exhibits around the world to find the most innovative displays and incorporated many of those aspects into this new museum.
Parents really like it, kids really like it and together they like it even more, says Daniel Koshland, a biochemist who founded the museum in honor of his late wife, Marian, who was a renowned molecular biologist and immunologist. NAS designed the museum, he says, to appeal to the average family visiting the nations capital.
Just blocks away from the Smithsonian museums, visitors to the Koshland Museum will learn about some of the fascinating facets of science that are in the public eye, including the causes and effects of global warming, and how scientists use DNA sequencing to solve crimes or prevent epidemic diseases. The aim, Koshland says, is to show how science affects peoples lives every day.
The first exhibit is a broad, introductory multimedia presentation called the Wonders of Science. It is the museums only permanent exhibit; in two years, the other exhibits will travel on tour. Interactive kiosks and a short video introduce visitors to some of the groundbreaking research that is unraveling the many mysteries of the universe.
After the video, visitors enter a compact but airy room filled to the brim with current facts about global warming and possible future effects. A giant orange globe beckons with the promise of illustrating the greenhouse effect firsthand: Each side of the globe simulates the extra warmth in an amplified greenhouse-heated world versus a naturally heated world. Global warming is a global problem, the exhibit says, but will be felt locally. On another display, by pressing buttons to raise sea levels and global temperatures, visitors can see what will happen to their own neighborhood; much of the Chesapeake Bay area, for example, would be underwater with a minor sea-level rise, according to the exhibit.
This topic the causes and effects of global warming is controversial, Koshland recognizes. But we take the position of illustrating the best science, he says. We dont do policy matters and we dont make science, he says, but the displays do show visitors what policies could cost them, as a way of relating big global issues on a very personal level.
One particularly sticky topic is future climate change, which is illustrated in this museum through a sliding plasma video screen of a world map over a wall-sized graph. The exhibit shows where and by how much temperatures and carbon dioxide levels are predicted to rise, according to climatic models from the National Center for Atmospheric Research and the Geophysical Fluid Dynamics Laboratory. Visitors can also examine what leads to the uncertainty in climate models, and at a nearby kiosk, begin to learn how they personally can impact the future. An emissions calculator offers choices of what activities each person could do to lower carbon-dioxide levels and then shows the results of the choices; for example, if Americans increased household vehicle efficiency by only 10 miles per gallon, carbon dioxide emissions would drop almost 5.5 percent annually.
State-of-the-art sliding plasma video screens at the Marian Koshland Museum illustrate changes in temperature and carbon dioxide levels around the world over the past 100 years. Another sliding plasma screen shows how temperatures and carbon dioxide levels are predicted to change over the next 100 years. Courtesy of the Marian Koshland Science Museum.
Visitors also have the chance to be part of a live research project about what personal tradeoffs they would be willing to make for the global good: Would each household be willing to pay $34 more per month to save the wetlands? How about $60 more per month to reduce emissions by 60 percent? Each visitor enters their response and it is recorded by Pennsylvania State University researchers. The researchers will then study individual responses to understand how to improve public policy in light of the tradeoffs people are or are not willing to make.
Not to be outdone, the past climate change exhibit is also fascinating. Interactive videos, posters and another sliding plasma screen show climate change from prehistoric times to this past century, and explain how climate proxies are used to determine what happened.
While Geotimes readers may be most interested in the climate change exhibit, also not to be missed is the fascinating, highly interactive DNA exhibit. Visitors use the same DNA methods the FBI uses to catch and convict a criminal, measure their DNA against Einstein and a chimpanzee, and discover how DNA is helping protect the public through genetic engineering of diseases and crops. This is high-level science that weve reduced to communicate in ways that are really fun, Koshland says.
The best pairing of people at the museum is parents with adolescents, says Bruce Alberts, president of NAS. The parents read the information, he says, while the kids push the buttons and get a lot out of the interactive portions of the exhibits. I just cant imagine a better way for parents to introduce their children to science.
MF-2396. Courtesy of the Marian Koshland Science Museum and Vicinity, Mohave County, Northwestern Arizona, by G.H. Billingsley and S.E. Graham. Prepared in cooperation with the National Park Service and Bureau of Land Management. 2003. Scale 1:31,680. One color sheet 39 x 45 inches with 27-page text. Available for $20.00 from USGS Information Services or free online.
MF-2410. ARIZONA. Geologic Map of the Upper Hurricane Wash and Vicinity, Mohave County, Northwestern Arizona, by G.H. Billingsley and H.C. Dyer. Prepared in cooperation with the National Park Service and Bureau of Land Management. 2003. Scale 1:31,680. One color sheet 38 x 44 inches with 23-page text. Available for $20.00 from USGS Information Services or free online.
MF-2418. ARIZONA. Geologic Map of Upper Clayhole Valley and Vicinity, Mohave County, Northwestern Arizona, by G.H. Billingsley and S.S. Priest. 2003. Scale 1:31,680. One color sheet 39 x 43 inches with 28-page text. Available for $20.00 from USGS Information Services or free online.
MF-2419. NEW MEXICO. Geologic Map of the Puye Quadrangle, Los Alamos, Rio Arriba, Sandoval, and Santa Fe Counties, New Mexico, by D.P. Dethier. 2003. Scale 1:24,000. One color sheet 40 x 30 inches. Available free online.
MF-2426. IDAHO and MONTANA. Geologic Map of the Bonners Ferry 30 x 60 Quadrangle, Idaho and Montana, by F.K. Miller and R.F. Burmester. 2003. Scale 1:100,000. One color sheet 33 x 52 inches with 31-page text. Available for $20.00 from USGS Information Services or free online.
I-2793. MARS. Topographic Map of the Margaritifer Chaos Region of Mars MTM 500k-10/337E OMKT, by U.S. Geological Survey. Prepared for NASA. 2003. Scale 1:502,000. One color sheet 28 x 40 inches. Available for $7.00 from USGS Information Services or free online.
I-2812. CENTRAL U.S. Earthquakes in the Central United States 1699-2002, by R.L. Wheeler, E.M. Omdahl, R.L. Dart, G.D. Wilkerson, and R.H. Bradford. Prepared in cooperation with the Central United States Earthquake Consortium and the Association of CUSEC State Geologists. 2003. Scale 1:250,000. One color sheet 57 x 43 inches. Available for $7.00 from USGS Information Services.
To order USGS maps: Contact USGS Information Services, P.O. Box 25286, Denver, Colo. 80225. Phone: 888-ASK-USGS (888/275-8747).
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