Forrest M. Mims III
Last year I attended a science conference
in Fairbanks, Alaska, where I heard much about the problem
of thawing tundra. I distinctly recall a drive along
a formerly flat road that had dips caused by thawed
That road was on my mind recently when
I looked at some remarkable photographs of shrinking
glaciers at World
View of Global Warming. This site shows how some
glaciers that once filled entire mountain valleys have
nearly disappeared. Photographs on this site show how
tundra has been thawing in Alaska and Sweden.
I also looked at a satellite image
of the largest glacier in North America, Alaska's Bering
NASA's Earth Observatory web site (Fig. 1). According
to the Earth Observatory site, "Warmer temperatures
and changes in precipitation over the past century have
thinned the Bering Glacier by several hundred meters.
Since 1900 the terminus has retreated as much as 12
Then today Ralph Coppola's "Wanderings"
column arrived with this item: "John
L. Daly's site lists sets of historical temperature
graphs from many stations around the globe." This
seemed like an interesting site to visit, which I did.
While numerous global warming web sites
make their point with photographs of disappearing glaciers,
Daly makes his with a staggering array of graphs
and data about the world's climate. The most significant
aspect of his site are its many plots of temperature
from many rural weather stations around the world. These
sites are important, for they are much less susceptible
to local and urban warming effects than the majority
of weather stations.
I looked for temperature records for
sites near the Bering Glacier, which is located in the
southeast corner of Alaska near the coast. Fortunately,
temperature has been recorded at two sites on either
side of the glacier, Cordova and Yakutat (Fig. 2). Figure
3 shows the data for both sites since 1909. The Earth
Observatory site reports that the Bering Glacier has
thinned because of warmer temperatures, but the plots
in Figure 2 don't seem to show an obvious warming trend.
It's well known that dust and carbon
particles can greatly reduce the albedo (reflectance)
of snow and ice, thereby increasing the absorption of
sunlight. NASA's James Hansen has shown that soot
alone may be causing significant melting of global ice
and snow. Besides soot produced from human activity,
including the burning of fossil fuels and large scale
burning for agricultural purposes around the world,
there is also soot from massive forest fires in Alaska,
Canada and Russia. The possible role of soot in melting
glaciers might someday be viewed as a major discovery,
particularly if it explains the melting of glaciers,
such as Bering Glacier, in the absence of any warming
trends. Deposition of dust from huge wind storms in
Africa and China may also play a role.
Meanwhile, John Daly's web site claims
that there are comparatively few indications of significant
warming or cooling trends in most of the numerous time
series it shows from around the world. This seems even
to apply to a remarkable temperature series from Central
England that extends from 1720 to 1998 (see Fig. 4).
While there has been a warming at this site in recent
decades, Daly points out that the measurements are subject
to urban heat island effects, for they are collected
from a heavily urbanized region.
An especially interesting chart shows
the temperature measured since 1869 at Valentia on the
southwest tip of Ireland (see Fig. 5). Daly believes
this site is significant because it has been well maintained,
and because, "...it is the first point of contact
in Europe for the Gulf Stream." Figure 5 also plots
the temperature at the Shannon Airport. He attributes
the gradual increase in the Shannon temperature to urban
development, a factor that is not significant at the
There is much more of this at Daly's
web site, including a troubling discussion of how questionable
data from some temperature sites in strange locations
are used in global climate models. He even shows a photograph
of one such site directly adjacent to a parking lot.
What's going on here? Countless web
sites cover various sides of the global warming issue,
but few seem to cover all the sides. Are time series
plots of average temperature as meaningful as those
that show minimum and maximum temperatures? Why doesn't
Daly's site include a photo album of melting glaciers?
Do any of the glacier sites show temperature records
or present James Hansen's findings about soot?
Perhaps it's time for serious citizen
scientists to examine global warming issues. One objective
might be to develop a comprehensive web site that covers
all sides of the warming issue, including the controversies.
As for the science, the web is filled with data about
every side of the issue, so it will not be necessary
to begin a data collection program.
The Bering Glacier paradox is a good
starting point. Figure 2 provides the temperature record,
and a PDF
report by Wendell Tangborn provides plenty of background
information about the glacier and its surges. Another
good project could be a study of why tundra is thawing.
If soot explains the melting of glaciers where no warming
is evident, what accounts for the thawing of frozen
soil in Alaska and Sweden? Plots showing the annual
temperature at Fairbanks, Alaska, since 1930 are
available at John
Daly's web site, and they seem to offer an important
clue. Fairbanks has grown considerably since I spent
four years in Alaska as a child. Growth inevitably brings
local warming, and the temperature plots seem to show
Citizen scientists who conduct serious
global warming studies are encouraged to submit their
findings for publication as feature articles in The
Citizen Scientist. General comments, tips and ideas
can be sent as e-mails to "Backscatter."