Way-Out Marina. The name of the landing from which Mead
Allison called at 11:00 AM told me our afternoon meeting did not stand a
chance. I was sitting in the offices of the Marine Sciences Program at Texas
A&M University-Galveston when I received word that Allison's sampling
mission in Galveston Bay stalled because his boat experienced engine trouble.
Way-Out Marina housed the only phone within hours and he only reached it
by hailing a passing fisherman. Allison did not return to Galveston until
nightfall.
It is no easy task to schedule a meeting with Allison,
a new Assistant Professor of Oceanography on the Galveston campus. He teaches
undergraduates for about one third of the work week and spent much of his
first two semesters preparing and stabilizing this teaching program. Due
to the emphasis on undergraduate teaching, he feels this first-year experience
in Galveston must differ considerably from that of his counterparts in College
Station.
But like most College Station faculty Allison came to Texas
A&M to run a research program, and he gestures proudly at the once-bare
room now occupied by instruments and graduate students. His active cruise
schedule takes him far beyond the Louisiana-Texas shelf to the eastern seaboard,
Brazil, and Bangladesh.
The challenge of joining the graduate faculty in Galveston,
Allison says, means wearing many hats without spreading himself too thin.
Numerous benefits include the opportunities to incorporate undergraduates
into his research programs (sometimes with pay), to help build Galveston's
research program, and to have significant influence while still an assistant
professor.
Williamsburg to Galveston-keeping with history
Allison's bright red hair and beard hint at his Scottish
ancestry, but he is a tenth-generation Virginian and grew up in Williamsburg
as the youngest of three children. He had two years experience at Woods
Hole Oceanographic Institution collaborating with the United States Geological
Survey (USGS) before coming to Texas A&M. He seems serious and pragmatic
in discussing his work, but the reserved side of Allison barely hides the
jovial and spontaneous aspects of his personality. His exotic cruise destinations
imply an adventurous streak that surfaces occasionally at home.
While new faculty regularly choose to live on the suburban
mainland, Allison and his wife, Victoria, bought an aging southern home
on Galveston's Mardi Gras parade route. The broad, divided street in the
Silk Stocking Historic District stretches between Monument Circle at one
end and the Gulf of Mexico at the other, lined with grandly refurbished
houses complete with wide, two-storied porches.
The Allison's own house remains the only one on the street
not yet restored, and it "needs a lot of love," he says with a
grin. He and Victoria spend their weekends renovating the home, with minimal
assistance from their cats. After successfully rebuilding the main bathroom,
they now plan to tear away the entire front wall which prior residents built
to enclose the Victorian porch. Allison hopes to return the porch to its
original state in time for the next Mardi Gras parade.
New meaning for "social" science
Allison's research life began with what he calls "hard-rock
geology." The specific events and circumstances that led him to oceanography
at East Carolina University escape memory, but the influence of activist
oceanographers such as Stan Riggs, Bill Cleary, Orrin Pilkey, and others
shows in Allison's work. He sees North Carolina as the state where coastal
advocacy by scientists emerged, recalling that Riggs, Cleary, and Pilkey
"led the way in the idea of scientists becoming involved in coastal
policythey drove through the toughest set of development laws in the country
at a time when they didn't exist anywhere else."
Allison advocates a practicable approach to coastal development.
"I think you have to maintain objectivity and be realistic," he
says. "There is development in the coastal zone and tremendous pressure.
Everybody wants to live here on the shoreline, or they want to play here
if they don't live here. It's unrealistic to say we are going to halt development,
and so the best you can do is try to guide things in a more wise fashion.
If you set yourself up as anti-development then the politicians and the
local people stop listening to you. I don't want to go that far."
Allison's own projects reflect this view. He thrives conducting
research that simultaneously consists of pure science and has real-world
applications for people dealing with coastal issues every day. This inclination
grows partly out of necessity but includes a healthy dose of intellectual
curiosity. "If you can't tie [research] to societal problems-"
Allison says, "the handwriting is on the wall about funding agencies-you're
not going to get much money. There are still some big basic research programs,
but all the exciting new stuff is coming out in things that are basic science
that you can directly apply to society."
Allison believes in a threefold strategy: conduct basic
research on sediment dispersal in the world's river and coastal systems,
actively influence policy, and train students to successfully populate industry
and government.
What do Bangladeshi farmers, musty London map rooms,
and Padre Island, Texas, have in common?
Each is a component of Mead Allison's research into the
movement of sediments. As one major focus, he hopes to describe river and
delta systems holistically, quantifying how much sediment "is parceled
out in the flood plain, remains in the channel, or makes it to the ocean
interface." Going further, Allison asks what part of the sediment load
entering the ocean "becomes part of subareal accretion, what goes out
on the shelf and is accreted, what goes downdrift and [becomes] shoreline
deposits, what goes into active submarine canyons, and what goes off-shelf?"
To find the answers Allison studies the world's largest
river systems. Gazing at a colorful map of Bangladesh he describes how the
entire country sits on a delta formed by the Ganges and Brahmaputra rivers.
Unless the monsoon fails, 40-50% of land in Bangladesh floods each year.
Sediments brought by the floods so enrich the farmers' fields that the country
stays largely self-sufficient in food even while struggling with abject
poverty.
Despite the obvious importance of this and other river
systems, much about their behavior remains unknown. Scientists once thought
the Mississippi River represents all large rivers and deltas. Now they know
each delta's character depends on complex geologic and climatic relationships,
even including the age of the mountains where its rivers are born.
Working in underdeveloped countries Allison sometimes has
to employ creative research techniques. In Bangladesh, he found that poor
farmers' recollections of sediment deposition on their fields during annual
floods closely corroborates empirical data from sediment cores. Their collective
memories help fill the gaps in sampled data.
Bangladesh's rivers meander wildly across the landscape,
and centuries-old changes also interest Allison. In 1780, the Brahmaputra
River shifted suddenly from its bed on the east side of a central Pleistocene
highland to the west side. The flood plain the river created in the east
is now subsiding and "sinking out of sight," Allison says. The
land compacts so quickly that annual floods again fill the vast plain completely.
Allison actually applied for funding to survey the plain in a boat using
marine seismic techniques. Observations of river sediment dispersed on the
old flood plain could shed light on the current process of deposition in
the west.
Few people today view the legacy of British colonialism
in India as positive, but it carries an unexpected benefit for Allison's
research. Surveyors in the British navy drafted precise maps of the Indian
(present-day Bangladeshi) coasts beginning in the early 1800s. Allison visited
the British archives in London and found that by painstakingly converting
projections and measurements, he can incorporate the maps into modern Geographic
Information Systems and trace changes in the delta from 1792 to the present.
Using the maps, he identified a previously unknown pattern
of delta formation. Over time, the Ganges-Brahmaputra river system created
a large underwater delta over which elongated lobes of coarse sediment from
the Himalayas accumulated. Comparing 19th-century charts with current ones
reveals that the river system deposits sediment lobes from west to east.
Old lobes no longer receiving sediment erode, subside, and eventually disappear.
This unexpected finding illuminates stages of delta formation and erosion
by large rivers worldwide, both in our own time and in the geologic record.
Simultaneously, Allison's work helps the government of Bangladesh take another
step toward understanding their delta and successfully developing their
country.
"There is no such thing as an average flood,"
Allison says. Each one differs, and populations that live near rivers must
learn to live with the variability. In Bangladesh, farmers welcome heavy
floods that fertilize their fields. Their families and communities move
with the flood waters, harvesting several crops per year by planting next
to recently receded waters. In contrast, rushing Mississippi torrents in
1993 forced less-adapted Americans from their homes and eradicated entire
towns.
Yet another large river, the Amazon, remains mostly free
from human interference, and Allison studies it as an example of a different
type of deltaic system. The Amazon River is so energetic that fine-grained
sediments do not settle out of the water column until they flow offshore
and drift along the coastlines of northern Brazil, the Guianas, and Venezuela.
Instead of forming a surface delta like the Missisippi or sediment lobes
like the Ganges-Brahmaputra, the Amazon forms an underwater delta that grows
outward along the continental shelf.
Rivers and deltas are not the only places where sediments
migrate. Beaches in the United States have little trouble attracting tourists,
but the sand that makes them so comfortable proves harder to keep. In Wrightsville
Beach, North Carolina, beach sand disappears so quickly that the city has
to replenish it every two years with sand from an estuary located slightly
inland. Investigating the cause, Allison and his colleagues from the USGS
and Duke University surveyed a swath of nearby coast and created a digital
map of the area. Their startling results may not bode well for Wrightsville
or its patrons.
Scientists once thought that sand eroded from beaches like
Wrightsville during storms remains fairly close, settling in shallow water
where it is washed back onshore during fair weather. But Allison's digital
map shows unsightly underwater gullies leading away from the beach. He speculates
that the gullies might act as drains through which sediment washes far offshore
into deep water during storms, out of reach of beach-shoreface recycling,
and permanently lost to the beach. Remnants of oyster shells, which originate
in Wrightsville's inland estuary but not in the ocean, have been found at
the ends of the gullies in deep waters. They were probably washed there
from the replenished beach.
The more digital maps Allison makes of different regions,
the more cross-shelf gullies he finds. Cross-shelf transport of sediment
now forms another theme in his research, and he looks forward to including
the Texas coast in his investigations. Allison recently negotiated an agreement
between Texas A&M University and his colleagues at the USGS to combine
resources and expertise in coastal projects. With this new partnership he
hopes to start examining some peculiar features of the Texas coast.
Everyone knows Texas loves to be different, and its south
coastal islands are no exception. While barrier islands worldwide erode
under the stress of coastal development and rising sea level, some Texas
islands are actually growing. Thanks in part to conservation measures implemented
decades ago, the islands remain fairly isolated from human activity. Now
Allison thinks the transportation of sediment there might be quite different
from the other regions he studies. In the future he wants to map offshore
areas around the islands to find out what accounts for their tenacity. Perhaps
cross-shelf features that seem so prevalent in the east are absent on the
south Texas coast. On the other hand, rivers draining into the gulf might
carry enough sediment to restore and expand the islands.
Coasting onward
Allison's students, both undergraduate and graduate, display
great enthusiasm for coastal science. Their intense interest stems partly
from the publicity engendered by the outspoken coastal scientists in North
Carolina and elsewhere. "The job of professors here," Allison
says, "is to take advantage of that and bring students up to speed
on what coastal science really is--present the broader picture of what coastal
science is really about. If they are the employees running the Corps of
Engineers in 20 years we are going to be a much more informed society."
Allison points to oceanography research at Texas A&M's
Galveston campus noting that many projects fit under the banner of coastal
studies. This foundation, he says, forms a solid base on which to add organized
coastal research to A&M's strong programs in open-water oceanography.
The proposed Center for Shelf and Coastal Oceanography (CSCO), currently
in the planning stages, will provide the opportunity to combine the strengths
of the College Station and Galveston campuses while responding to the needs
of students and society.
On a more personal level, being a part of emerging research
programs in Galveston and helping to plan CSCO lets Allison adopt a leadership
role while still an assistant professor. His willingness to try new approaches
and techniques in research shows that he likes to break new ground, and
plenty of challenges lie ahead to satisfy his adventurous side.
Two new faculty positions in coastal studies will open
in Galveston soon, and Allison predicts that soon the number of researchers
will reach a critical mass and "coastal studies in Galveston will really
start surging forward." |
Compare
the 1840 and the 1984 Bay of Bengal