Temperatures, Not Hotels, Likely Alter
Niagara Falls' Mist
University at Buffalo
When the Niagara Parks Commission posed that question back
in 2004, the concern was that high-rise hotels on the Canadian
side of Niagara Falls were contributing to the creation of
more mist, obscuring the very view that millions of tourists
flock there every year to see.
The suspicion was that new high-rise buildings were altering
airflow patterns, contributing to a higher, thicker mist plume.
Consultants conducted wind tunnel experiments that seemed
to confirm that mist levels were enhanced by the tall buildings
around the falls, a report that circulated in the Canadian
news media.
Now University at Buffalo geologists have determined that
the high-rise hotels are probably not to blame.
"According to our findings, it is unlikely that the
buildings at the falls enhance the mist," said Marcus
Bursik, Ph.D., professor in the Department of Geology in the
UB College of Arts and Sciences, who led the study with several
students who were investigating the plume for their graduate-degree
projects. "Rather, our data show that it's air and
water temperature that control the amount of mist.
"It turns out that the bigger the temperature difference
between the air and the water, the higher and more substantial
is the mist plume and the thicker is the mist at the Falls,"
he continued.
Bursik, a volcanologist who has studied atmospheric plumes
at volcanoes, noted that plumes, regardless of their origin,
have common features.
He was motivated to study the Niagara Falls plume back in
2002.
"I started wondering why the plume rose to different
heights on different days," said Bursik, who often
can see the plume from his building on the University at Buffalo's
North (Amherst) Campus about 20 miles away.
According to the data the UB researchers gathered, the plume
is highest during times of the year when the water temperature
is higher than the air temperature, which typically occurs
during fall and winter.
Bursik explained that in late autumn, even when the air temperature
can fall to about 40 or 30 degrees Fahrenheit, the water still
remains quite warm, as high as 60 degrees Fahrenheit, conditions
that are ideal for a large, high plume.
During the winter, he continued, the temperature of the water
remains at 32 degrees Fahrenheit because it is constantly
flowing, but the air temperature will plunge by twenty or
thirty degrees or more.
"Those temperature differences create more mist flow
and a higher plume," said Bursik.
The perception that there have been more misty days in recent
years may just be related to temperature trends, he noted.
Using a portable weather station adapted for a backpack,
a UB student measured windspeed at the falls to establish
airflow and windflow patterns.
Calculations also were made using ambient atmospheric temperature
and river-water temperature to make a prediction for the height
of the mist plume.
Actual plume height then was measured on different days using
the Skylon Tower as a reference point.
"The predicted and measured plume heights matched
well, consistent with the notion that the plume is just higher
and thicker when the temperature difference is bigger,"
said Bursik.
The researchers will present their findings at UB's annual
Environment and Society Institute Colloquium on April 21.
Findings also were presented during the 36th Binghamton Geomorphology
Symposium held at UB last October.
The research was supported by seed funding from UB.
The University at Buffalo is a premier research-intensive
public university, the largest and most comprehensive campus
in the State University of New York.
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