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CCNet DIGEST, 28 January 1999
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(1) NATURE'S ROLE IN THE RISE AND FALL OF HUMANITY
    ABC NEWS

(2) SUN MAY PLAN UNRECOGNISED ROLE IN GLOBAL WARMING
    Andrew Yee <ayee@nova.astro.utoronto.ca>

(3) ASTRONOMER LOOKS AT DEEP BIOSPHERE AND FINDS IT TEEMING WITH LIFE,
    AND CONTROVERSY
    Andrew Yee <ayee@nova.astro.utoronto.ca>

(4) SHOULD SCIENTISTS BECOME PLAYERS IN PUBLIC POLICY DEBATE?
    AAAS

(5) THE FUTURE ISE AIMS OF NASA
    D.S. Goldin et la., NASA HEADQUARTERS

(6) ACCRETION IN THE EARLY KUIPER BELT
    S.J. Kenyon*), J.X. Luu, HARVARD SMITHSONIAN CTR ASTROPHYS

=====================
(1) NATURE'S ROLE IN THE RISE AND FALL OF HUMANITY

From ABC NEWS
http://abcnews.go.com/sections/science/DailyNews/paleoclimate990127.html

By Kenneth Chang
ABCNEWS.com

HOW CLIMATE SHAPED HISTORY

If it weren’t for a prolonged cool spell about 12,500 years ago,
perhaps we’d still be hanging out as hunter-gatherers and never
bothered with civilization.

At that time, a major source of food for people living in the Middle
East was vast fields of einkorn, wheat, barley and rye.

These plants, particularly sensitive to cool temperatures, suffered
when the warmth since the last Ice Age was interrupted by a
1,000-year-long cool and dry period called the Younger Dryas.

Necessity is the Mother of Farming

The beginnings of farming appear to coincide with the Younger Dryas.
According to Ofer Bar-Yosef, an anthropologist at Harvard University’s
Peabody Museum, that’s no coincidence. Instead of relying on what was
growing naturally, he says, people started clearing land and planting
seeds to insure they would have enough food.

“It caused people to initiate cultivation,” he says. Bar-Yosef’s
findings also narrow the location of the first farmers to the western
half of the “Fertile Crescent” — an arcing swath of the Middle East,
from the Persian Gulf north to Turkey and then back down through Syria,
Lebanon and Israel toward Egypt.

According to Bar-Yosef, the wild varieties of grains thrived in the
western region and were transplanted elsewhere later. As people settled
down and developed agriculture, towns and eventually civilization
arose.

That’s not the only time that climate may have shaped the course of
humanity. Bar-Yosef and other researchers presented findings about
climate and civilization last Saturday at the American Assocation for
the Advancement of Science meeting in Anaheim, Calif.

“We are probably more affected more by weather and climate than we
think we are,” says Paul Mayewski, director of the Climate Change
Research Center at the University of New Hampshire and another of the
speakers at the Anaheim session.

Not Always Like Today

Until a few years ago, most scientists believed the climate of the past
11,000 years — a period known as the Holocene that followed the Younger
Dryas — has been stable and uninteresting, and thus of little influence
on the fortunes of civilization.

However, climate records reconstructed from ice and sediment cores
around the world paint a less benign weather history. While the
temperature and rainfall swings haven’t been as wild as some periods in
Earth’s history, they do appear enough to topple nations.

Excavations of Tell Leilan, a town in what is now northeast
Syria, tell such a story. In 2280 B.C., a civilization called the
Akkadians absorbed Tell Leilan. A century later, the town had emptied
out and remained unpopulated for three centuries. The entire Akkadian
civilization collapsed and disappeared.

“There is a depopulation, desertion of northern Mesopotamian region,”
says Harvey Weiss, professor of prehistorical archaeology at Yale
University, who led excavations at Tell Leilan, “and Tell Leilan’s
abandonment is simply typical of that process.”

Long Drought

Climate records show rainfall dried up in the Middle East around 2200
B.C., which would have deprived farmers of needed winter rains.

In cores dug up in the Gulf of Oman to the south, sediments deposited
during this time show very different minerals, indicating different
wind patterns. Other archaeological sites show that cities to the
south, surrounded by irrigated fields, swelled in population at the
same time..

When the climate connection to the Akkadian collapse was first
presented a few years ago, some wondered whether farmers had
inadvertantly caused their own ruin by overfarming. Data from other
researchers gleaned from lake sediments around the world indicate the
2200 B.C. climate shift was a global event.

“This has now put a lot more details together for it,” Weiss says.

Another major climate swing was the Little Ice Age, which froze Europe
in the 1400s and killed off Viking settlements in Greenland. And
perhaps also the one occurring today.

Temperatures, nudged up by emissions of greenhouse gases, have risen
sharply since the beginning of the century, but the wind patterns are
largely unchanged, creating an unnatural combination of
conditions.
   
“You put those two together,” Mayewski says, “you have potentially
greater instability in climate. It could turn out it is more important
that humans have changed the stability of climate than just the
temperature.” Those potential instabilities — droughts, heat waves,
fiercer storms — could change the course of history yet to come.
          
Copyright 1999, ABC NEWS

==================
(2) SUN MAY PLAN UNRECOGNISED ROLE IN GLOBAL WARMING

From Andrew Yee <ayee@nova.astro.utoronto.ca>

University of California-Los Angeles

Contact: Stuart Wolpert, stuartw@college.ucla.edu, (310) 206-0511

January 26, 1999

Sun May Plan Unrecognized Role in Global Warming, UCLA Astronomer
Suggests

UCLA astronomy professor Roger Ulrich raises this question: Is the sun
affecting global warming? Ulrich believes the sun could play a larger
role than most scientists think. Ulrich, whose research focuses on the
sun, noted that the sun's surface can be divided into three types of
regions: relatively small regions that appear as sunspots and where an
intense magnetic field is as much as 8,000 times stronger than the
Earth's magnetic field; a larger region where the magnetic field is as
much as 200 times stronger than the Earth's; and a huge region that
covers some 80 percent of the sun, where he estimates the magnetic
field is about 10 times stronger than the Earth's. Ulrich's research
focuses on this last region, with the relatively weak magnetic field,
which he believes may play a larger role in the Earth's climate than
has been realized.

Every 11 years the sun undergoes a cycle where the strength of its
magnetic fields rises and falls. Sunspots, many of them larger than the
Earth itself, appear on the surface where the magnetic field is most
intense for the first three to four years of the cycle, then recede
during the remainder of the cycle. At low points in the cycle, the sun
only occasionally will have a spot on its surface; at peak times, the
sun may have dozens visible at once, Ulrich said.

Speaking at the annual meeting of the American Association for the
Advancement of Science in Anaheim on Jan. 23, Ulrich proposed that the
80 percent of the sun with a relatively weak magnetic field may follow
a much longer cycle that is a delayed response to the 11-year solar
cycle. He further suggested that the weak field's longer cycle may help
to explain the "little ice age" that occurred on Earth from
approximately 1650-1710, and may affect the Earth's climate.

During the "little ice age," sunspots virtually disappeared from the
solar surface for six decades, Ulrich said. The sun's surface had only
one sunspot every decade during this time, and none for about 20 years.
If sunspots were to go away, the sun would put out less energy, which
could make it colder, Ulrich said -- and it was colder during these six
decades when sunspots were not present.

At the AAAS meeting, Ulrich presented new evidence, collected over 11
years, from Mount Wilson's Solar 150-foot Tower Telescope. He is the
first scientist to make measurements of the sun's weak magnetic field
over an extended period. This research is the first step to measure the
strength of the magnetic field over 80 percent of the sun's surface.

As Ulrich continues the research, he seeks to learn what would happen
to the sun if the weak field went away and to estimate the effect. He
suspects that the field may have gone away during the 60-year period
starting in 1650, and said it is possible that it will happen again.

Scientists have not known much about what happens on this 80 percent of
the sun's surface; no one had measured what occurs at this region
before.

Ulrich's observations indicate that as the sunspots go away, the rest
of the magnetic field starts to go away as well; but before the
magnetic field can dissipate over the 80 percent region, a new sunspot
cycle begins. For 80 percent of the sun, therefore, the magnetic field
does not go away completely when sunspots are at a minimum, it just
drops slightly.

"The weak magnetic field tries to decay at sunspot minimum, but does
not have time before the sunspots return and refresh it," Ulrich said.
"The weak fields may be responding to the strong fields. During the
little ice age, the weak field may have gone away, affecting the
Earth's climate."

While scientists had dismissed the sun as a factor in global warming,
Ulrich said there may be a longer-term trend that has not been factored
in coming from this 80 percent region of the sun. Ulrich thinks it is
"reasonably likely" that the weak field plays a larger role than has
been assumed.

During this century, the number of sunspots has increased, Ulrich noted.

Ulrich's research is supported by NASA, the Office of Naval Research
and the National Science Foundation. His colleagues are Judit Pap, UCLA
research astronomer; and graduate student Daryl Parker.

==================
(3) ASTRONOMER LOOKS AT DEEP BIOSPHERE AND FINDS IT TEEMING WITH LIFE,
    AND CONTROVERSY

From Andrew Yee <ayee@nova.astro.utoronto.ca>

News Service
Cornell University

Contact: David Brand
Office: (607) 255-3651
E-Mail: deb27@cornell.edu

Cornell astronomer looks at our deep hot biosphere and finds it teeming
with life , and controversy

ITHACA, N.Y. -- The ideas come crowding in: Deep within the Earth's
crust is a vast ecosystem of primitive bacteria nurtured by a reservoir
of hydrocarbons of unimaginable size, much of it untapped. Even more:
The microbes predate all of the planet's other life forms, existing
even before photosynthesis became the preferred life-giving form.

In a new book, The Deep Hot Biosphere (Copernicus/Springer-Verlag,
$27), Cornell Professor emeritus of astronomy Thomas Gold argues that
subterranean bugs are us -- or at least they started the whole
evolutionary process, and that there's no looming energy shortage
because oil reserves are far greater than predicted.

In the hands of anyone other than Gold, the reaction to all this might
be a skeptical raised eyebrow. But Gold, as ever the Cornellian gadfly,
makes his argument with erudition and conviction. Founder and director
of Cornell's Center for Radiophysics and Space Research for two
decades, Gold is hardly a stranger to sticking his neck out. He has
been proven right in such diverse realms as a theory of hearing, the
interpretation of pulsars and a theory of the Earth's axis of rotation.

But Gold's most controversial idea, as physicist Freeman Dyson notes in
the book's forward, is that of the nonbiological origin of natural gas
and oil, which he first proposed more than 20 years ago. These
hydrocarbons, Gold postulated, come from deep reservoirs and are
composed of the material from which the Earth condensed. The idea that
hydrocarbons coalesced from organic material is, he says, quite wrong.
The biological molecules found in oil, he avers, show only that the oil
is contaminated by microbes, not that it was produced by them.

Some researchers, and in particular petroleum geologists, have taken
issue with Gold's proposal. They are likely to be even more put out by
his new book, which says that these microbes populate the Earth's
interior down to a depth of several miles and that everything we see
living on the planet's surface is only a small part of the biosphere.
The greater part, and the ancient part, is very deep and very hot.

Indeed, Gold shows irritation at a scientific community that "has
typically sought only surface life in the heavens." Scientists, he
writes, "have been hindered by a sort of 'surface chauvinism.'"

The heavens?

Absolutely, says Gold. "Spectroscopic evidence is very strong for many
planetary bodies. The prime example is Titan [a moon of Saturn], which
has clouds of ethane and methane. They interchange with the surface, so
there must be lakes or oceans of liquid ethane or methane. Once you
know that, it's clear they came outside from the body within."

Thus, he writes, life on many other planetary bodies seems probable,
even though their surfaces are either too hot or too cold to support
life. "Subsurface life, however, is another matter. Mars, the
satellites of the major planets, many asteroids and even our own moon
should be regarded as real prospects for harboring extraterrestrial
life of this kind," he writes.

On Earth, says Gold, there is clear evidence that subsurface microbial
life still exists; for example, in the discovery of primitive microbes
in hot ocean vents. "We pulled up bugs from five kilometers down in the
granite in Sweden. They were perfectly alive and probably the earliest
life form on the planet," he says. The primitive microbes, he notes,
are thermophiles and hyperthermophiles, heat-loving archaebacteria.

Photosynthesis, his book argues, "developed in offshoots of
subterranean life that had progressed toward the surface and then
evolved a way to use photons to supply even more chemical energy." When
surface conditions such as temperature and liquid water became
favorable to life, surface life was able to blossom.

In the eons since, the deep world of microbes has had to rely on
chemical energy, the oxidation of hydrocarbons, ranging from methane to
petroleum, as the organisms emerge upwards from deep reservoirs below.
"Every oil-bearing region in the world must have large amounts of
microbiology," he says.

Writes Gold: "In my view, hydrocarbons are not biology reworked by
geology (as the traditional view would hold) but rather geology
reworked by biology. In other words, hydrocarbons are primordial, but
as they upwell into Earth's outer crust microbial life invades."

Reviewing the book, Publishers Weekly noted that "if Gold is right, the
planet's oil reserves are far larger than policy-makers expect ...
moreover, astronomers hoping for extraterrestrial contacts might want
to stop seeking life on other planets and inquire about life in them."

Related World Wide Web sites:

The following sites provide additional information on this news
release. Some might not be part of the Cornell University community,
and Cornell has no control over their content or availability.

Thomas Gold's overview of his new book, The Deep Hot Biosphere:
http://www.people.cornell.edu/pages/tg21/

==================
(4) SHOULD SCIENTISTS BECOME PLAYERS IN PUBLIC POLICY DEBATE?

From the AAAS

ANAHEIM, Calif. - As the 20th century draws to a close, scientists are
under increasing pressure - and some say, obligation - to use their
research data and their status to influence public policy. That
decision to mix politics with science, says Mary Jo Nye, is fraught
with peril.

The Horning Professor of Humanities at Oregon State University, Nye
delivered the annual George Sarton Memorial Lecture Sunday at the
annual meeting of the American Association for the Advancement of
Science (AAAS) in Anaheim, Calif.

In her talk, Nye said that scientists who choose to take public stands
on issues risk attack from members of the public who question their
objectivity and neutrality, and from fellow scientists who may dispute
their interpretation of data, or feel that science and politics should
not mix. When scientists argue publicly over data, or accuse each
other of partiality, public confidence in science can be undermined.

However, Nye added, if scientists do not become involved in public
policy debates, the result can be a decision-making process involving
complex, critical issues that aren't fully understood.

"Scientists have come to feel a social and political responsibility to
bring scientific and technical data to the public in order to influence
decisions on complicated matters of national and global significance -
not only questions of war and peace...but on specific strategies for
armament and disarmament, for nuclear energy and nuclear waste, for
endangered species and natural habitats, and for global temperature
change," Nye said.

Nye is a professor of the history of science at Oregon State
University, which is the alma mater of the late Linus Pauling, the only
individual to win two unshared Nobel Prizes. Pauling was one major 20th
century scientist who discovered the rewards, and hazards, of taking a
public stand on a controversial issue and of arguing with fellow
scientists in public, Nye said.

Pauling's efforts to halt the testing of atomic weapons garnered him
the 1962 Nobel Peace Prize, but also earned the wrath of fellow
scientists and the alienation of some academic and government leaders.

The chasm separating science and politics first began to close during
World War I, when chemists became involved in their respective
governments' efforts to create chemical weapons. Several scientists on
both sides of the Atlantic Ocean became involved, either in protesting
the war or signing manifestos defending their country's actions.

A small group of scientists led by Albert Einstein advocated that
scientists band together and not become involved in war-related
research or governmental advocacy, Nye said.

"When the war ended, though, most of these scientists went back to
doing what they were doing before the war, which usually was
unrelated," Nye pointed out.

A second major phase that brought scientists into the public arena
occurred in the 1920s and 1930s, when the stock market had crashed and
Fascism was on the rise. A handful of scientists led by Paul Langevin
and Jean Perrin took on highly visible roles in socialist,
anti-fascist, and pacifist organizations - all committed toward
improving the lives of the working class.

"Politically, it was very much a 'campaign for science,'" Nye said,
"which stressed the need for broader scientific education, increased
funding for scientific research and better coordination of fundamental
and applied research. The assumption was that socialism was better for
science than was capitalism or fascism."

At the same time, a group of left-wing scientists in Britain began
writing newspaper and magazine articles, and organizing fellow
scientists to discuss their responsibilities to improve education and
industry as well as science. Then during World War II, the Manhattan
Project and other war-related research took the question of scientific
involvement to a new level, Nye said. Questions arose as to whether
scientists should study atomic energy for military use - and whether
new research findings should be kept secret or shared. Once the atomic
bomb was developed and used, would the United States share the
technology, and with which countries?

"Much of the debate focused on an Atomic Energy Commission, which
surely would be set up after the war," Nye said. "The big question
was: would it be run by civilians, in which it likely would be open?
Or by the military, which would keep the research secret.

"This fear of atomic weapons, and the pervasive atmosphere of
distrust, was the very origin of the Cold War," she added.

The arguments continued after the war, spurred on by fear of an
escalating arms race. Like Pauling, British physicist P.M.S. Blackett
played a visible, and highly controversial role. A respected
scientist, Blackett had earlier argued - behind closed doors - that
Britain should not enter the arms race and that the U.S. and Britain
should trust the Soviet Union. He lost on both accounts.

"So Blackett took his argument to the public," Nye said. "He published
a book analyzing military strategy and claimed that the bombing of
Hiroshima and Nagasaki had changed the way military leaders would wage
war, prompting them to use strategic bombing instead of 'conventional
warfare.'

Nye said Blackett believed such bombing was effective at destroying
cities, but ineffective at winning wars. He provided in-depth
arguments outlining the bombs' "explosive power," or TNT equivalent,
and other technical data.

"Regardless of whether you agreed with his reasoning, Blackett did one
thing that stood out - he brought technical arguments into the public
forum and prompted scientists to publicly debate research data," Nye
said.

And now, she said, there is no going back.

"The 20th century has seen scientists who have taken their expertise
and reputations into public forum inevitably risk censure both from
within and without the scientific community," Nye said. "And there may
be risks to the public's confidence in science when scientists bring
into public discussion technical matters on which experts themselves
cannot agree, and on which non-experts feel free to express an opinion.

"But in the long run," she added, "some notable scientists have thought
the perils are worth the risks."

===================
(5) THE FUTURE ISE AIMS OF NASA

D.S. Goldin, S.L. Venneri, A.K. Noor: Beyond incremental change.
COMPUTER, 1998, Vol.31, No.10, p.31ff

NASA HEADQUARTERS, TECHNOL. LEADERSHIP COUNCIL, WASHINGTON,DC

In the next 25 years NASA has ambitious goals: It wants to accurately
predict climate and resources over decades, not just daps. It wants to
detect Earth-sized planets 600 trillion miles away with a telescope
powerful enough to determine signs of life. It wants to use the
International Space Station as a platform for an astronaut to visit
Mars. This is the big vision, and to many it may sound more like
science fiction. To help achieve these goals, in 1997 NASA and the
University of Virginia's Center for Advanced Computational Technology
began planning and developing the Intelligent Synthesis Environment.
The ISE aims to link scientists, design teams, manufacturers,
suppliers, and consultants in the creation and operation of an
aerospace system and in synthesizing its missions. The ultimate goal is
to significantly increase creativity and knowledge and eventually
dissolve rigid cultural boundaries among diverse engineering and
science teams. Copyright 1999, Institute for Scientific Information Inc.

====================
(6) ACCRETION IN THE EARLY KUIPER BELT

S.J. Kenyon*), J.X. Luu: Accretion in the early Kuiper Belt. I.
Coagulation and velocity evolution. ASTRONOMICAL JOURNAL, 1998,
Vol.115, No.5, pp.2136-2160

*) HARVARD SMITHSONIAN CTR ASTROPHYS,60 GARDEN ST,CAMBRIDGE,MA,02138

We describe planetesimal accretion calculations in the Kuiper Belt. Our
evolution code simulates planetesimal growth in a single annulus and
includes velocity evolution but not fragmentation. Test results match
analytic solutions and duplicate previous simulations at 1 AU. In the
Kuiper Belt, simulations without velocity evolution produce a single
runaway body with a radius r(i) greater than or similar to 1000 km on a
timescale tau(r) proportional to M(0)(-1)e(0)(x), where M-0 is the
initial mass in the annulus, e(0) is the initial eccentricity of the
planetesimals, and x approximate to 1-2. Runaway growth occurs in 100
Myr for M-0 approximate to 10M(E) and e(0) approximate to 10(-3) in a 6
AU annulus centered at 35 AU. This mass is close to the amount of dusty
material expected in a minimum-mass solar nebula extrapolated into the
Kuiper Belt. Simulations with velocity evolution produce runaway
growth on a wide range of timescales. Dynamical friction and viscous
stirring increase particle velocities in models with large (8 km
radius) initial bodies. This velocity increase delays runaway growth by
a factor of 2 compared with models without velocity evolution. In
contrast, collisional damping dominates over dynamical friction and
viscous stirring in models with small (80-800 m) initial bodies.
Collisional damping decreases the timescale to runaway growth by
factors of 4-10 relative to constant-velocity calculations. Simulations
with minimum-mass solar nebulae, M-0 similar to 10M(E), and small
eccentricities, e approximate to 10(-3), reach runaway growth on
timescales of 20-40 Myr with 80 m initial bodies, 50-100 Myr with 800 m
bodies, and 75-250 Myr for 8 km initial bodies. These growth times vary
linearly with the mass of the annulus, tau(r), proportional to M-0(-1),
but are less sensitive to the initial eccentricity than
constant-velocity models. In both sets of models, the timescales to
produce 1000+ km objects are comparable to estimated formation
timescales for Neptune. Thus, Pluto-sized objects can form in the outer
solar system in parallel with the condensation of the outermost large
planets. Copyright 1999, Institute for Scientific Information Inc.

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