Betting on climate change: Alaskan gambling contest yields treasure trove of scientific data

October 25, 2001

A celebrated betting pool in Alaska is providing researchers with a remarkably accurate record of global climate change, according to a new study in the journal Science. And the results show that spring is coming earlier and earlier.

Every spring, the Alaskan village of Nenana (population 500) hosts the Nenana Ice Classic - a popular event that awards cash prizes to those lucky enough to guess when the annual ice breakup will occur on the nearby Tanana River. Winners must predict the exact minute that a specially constructed wooden tripod will crash through the icy surface.

Hundreds of thousands of people pay $2 a ticket to enter the contest. This year`s jackpot of $308,000 was divided among 18 winners who accurately predicted that the tripod would fall through the ice on Tuesday, May 8, at exactly 1 p.m.

For many Alaskans, the Ice Classic signifies the long-awaited arrival of spring. But for Stanford scientist Raphael Sagarin, the event is more than symbolic.

"What began as a wintertime diversion for railroad engineers has given us an unusual 84-year data set on the timing of river ice breakup," says Sagarin, a postdoctoral fellow at Stanford`s Hopkins Marine Station in Pacific Grove, Calif.

Writing in the Oct. 26 issue of Science, Sagarin and Fiorenza Micheli, assistant professor of biological sciences, explain how the Ice Classic and other historical records can serve as valuable tools for researchers studying global warming.

"Because scientists weren`t thinking about climate change 80 or 90 years ago, it`s really important that people kept these data," notes Sagarin, who has a keen interest in phenology - a branch of science that looks at the annual timing of natural events, such as bird migrations.

"Phenology used to be dismissed as a hobby of eccentric British naturalists, some of whom have family records dating back to the 1750s of when the first leaf appeared on a particular tree in spring," Sagarin says.

Ingenious contraption

The Nenana Ice Classic was created in 1917 by engineers building a railroad bridge across the Tanana River, about 50 miles southwest of Fairbanks. When the river froze, the engineers had to stop work. According to Ice Classic historians, idle speculation about when the ice would break up is what led to the wagering.

To determine the contest winner, the engineers came up with an ingenious contraption still in use today. It consists of a tall tripod made of wooden logs painted with black-and-white stripes. A wire is attached from the top of the tripod to a clock on shore. When melting ice causes the tripod to move 100 feet, the clock stops automatically. The tripod and clock are monitored 24 hours a day by sharp-eyed villagers working in shifts.

"Contest records of the exact minute of ice breakup date back to 1917 and can be considered quite accurate, as the high stakes lead to constant vigilance at the time of breakup," write Sagarin and Micheli.

"The Nenana contest may be especially valuable because it is based on a more consistent definition of ice breakup than many records," they add.

The authors point out that river ice breakup is caused by a combination of thermal effects - when the ice "rots" or melts slowly - and dynamic effects - mechanical forces from upstream drift ice.

"Warmer climate would be expected to advance the time of breakup through both thermal effects and dynamic effects, due to thinning ice and increased snowmelt runoff into rivers," explain Sagarin and Micheli.

Early spring

The authors analyzed the entire Ice Classic record and discovered that, on average, the Tanana River breakup occurs 5.5 days sooner than it did back in 1917. The earliest breakup on record took place on April 20, 1998; the latest on May 20, 1964.

"These results show that springtime is coming earlier," notes Sagarin. "This trend also matches up pretty well with historic temperature data from Nenana and Fairbanks."

He says that other phenological records from around the world documenting the springtime appearance of birds and new plant growth also reveal that spring is coming sooner - an indication that climate change is a reality that is affecting natural systems on Earth.

"This is nontraditional scientific knowledge, but simple observations are very important. For example, river ice breakup has direct economic consequences, because people who live along the Tanana rely on waterborne commerce," Sagarin says.

"Phenology was pooh-poohed until recently, but now it`s recognized as important data, because climate change is a relatively recent phenomenon that has caught scientists by surprise," he adds.

Sagarin says he might use his linear regression analysis to predict when the breakup will occur next spring.

His advice for those contemplating purchasing a ticket for the 2002 Ice Classic: "I wouldn`t enter a date that`s too late in the year."
-By Mark Shwartz-

News Service website:

Stanford Report (university newspaper):

COMMENT: Raphael Sagarin, Department of Biological Sciences, Hopkins Marine Station (831) 655-6251;

EDITORS: Photographs of the Nenana Ice Classic can be downloaded at (slug: "Alaska Bet"). The study, {"Climate Change in Nontraditional Data Sets," appears in the Oct. 26 issue of Science magazine. Advance copies are available from Lisa Onaga at

Relevant Web URLs:

Stanford University

Related Climate Change Articles from Brightsurf:

Are climate scientists being too cautious when linking extreme weather to climate change?
Climate science has focused on avoiding false alarms when linking extreme events to climate change.

Mysterious climate change
New research findings underline the crucial role that sea ice throughout the Southern Ocean played for atmospheric CO2 in times of rapid climate change in the past.

Mapping the path of climate change
Predicting a major transition, such as climate change, is extremely difficult, but the probabilistic framework developed by the authors is the first step in identifying the path between a shift in two environmental states.

Small change for climate change: Time to increase research funding to save the world
A new study shows that there is a huge disproportion in the level of funding for social science research into the greatest challenge in combating global warming -- how to get individuals and societies to overcome ingrained human habits to make the changes necessary to mitigate climate change.

Sub-national 'climate clubs' could offer key to combating climate change
'Climate clubs' offering membership for sub-national states, in addition to just countries, could speed up progress towards a globally harmonized climate change policy, which in turn offers a way to achieve stronger climate policies in all countries.

Review of Chinese atmospheric science research over the past 70 years: Climate and climate change
Over the past 70 years since the foundation of the People's Republic of China, Chinese scientists have made great contributions to various fields in the research of atmospheric sciences, which attracted worldwide attention.

A CERN for climate change
In a Perspective article appearing in this week's Proceedings of the National Academy of Sciences, Tim Palmer (Oxford University), and Bjorn Stevens (Max Planck Society), critically reflect on the present state of Earth system modelling.

Fairy-wrens change breeding habits to cope with climate change
Warmer temperatures linked to climate change are having a big impact on the breeding habits of one of Australia's most recognisable bird species, according to researchers at The Australian National University (ANU).

Believing in climate change doesn't mean you are preparing for climate change, study finds
Notre Dame researchers found that although coastal homeowners may perceive a worsening of climate change-related hazards, these attitudes are largely unrelated to a homeowner's expectations of actual home damage.

Older forests resist change -- climate change, that is
Older forests in eastern North America are less vulnerable to climate change than younger forests, particularly for carbon storage, timber production, and biodiversity, new research finds.

Read More: Climate Change News and Climate Change Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to