The Nenana Ice Classic 2002


 How to Lose Money Gambling on Global Warming


The Nenana Ice Classic [1] results are in and if you bet on global warming this year you lost. Last year, in the October 26, 2001 issue of Science [2], a much acclaimed article by Raphael Sagarin and Fiorenza Micheli, asserted that "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" [3]. At the time of its publication the paper was widely heralded as yet another indicator of global warming [3, 4, 5, 6].  Dr. Sagarin's advice for the 2002 Ice Classic was: "I wouldn't enter a date that's too late in the year" [3]. 

John Daly wrote an excellent review [7] of the paper, documenting many problems with fundamental assumptions and analytical treatment of the data. One of the more egregious inconsistencies, identified by Daly, was the omissions on the 2001 results from both the analysis and the graph in Fig. 2A. This omission of 2001 data was made in spite of the fact that Fig. 1 of the paper contained a picture of the raising of the Nenana tripod on the Tanana River during March of 2001. If there is any credibility to the claim that the time of ice breakup at Nenana is a valid proxy of prevailing climatic conditions, the 2001 results were significant because they occurred later than the average historical breakup date. 

With the glaring omission of the politically incorrect 2001 Nenana results in mind,  Climate Skeptics waited for the 2002 Nenana results with some interest. During the vigil, we learned that 2001 was the "Second warmest year globally since records began " [8] and that the winter of 2001-2002 was the warmest on record [9] for most of the United States, including Alaska. It was a time when it was much easier being Green then being a Skeptic. While the CRU and NOAA continued to predict global meltdown, a funny thing was happening on the Tanana River. The ice at Nenana was setting near record thicknesses [1] and the local newspapers were reporting [10, 11] how cold and miserable the weather was. The Nenana web site provided a table of ice thickness from 1989 through 2002. Based on the historical record and the then current ice thickness, by the end of March I projected that ice breakup would occur well past the average breakup date which was March 5 or Julian day 125.  I used two models, one based on the average ice thickness and the second based on the last measured thickness before breakup. Ice measurements are usually discontinued a week or two before breakup for safety reasons. 

The earliest breakup date of April 20 (Julian 110) came and went with the ice holding at 47 inches thick. On April 29 the ice had thinned to 42 inches and measurements were discontinued because the ice was too rotten. At that point I was projecting a breakup date of May 8 (Julian 128), as show in the following graph, where the green dot is the actual time of breakup and the intercept of the red and black lines was the projected breakup date:   


 During the first week of May, Fairbanks which is up river from Nenana, experienced heavy rains [12], which accelerating the rotting of the ice and on May 7, 2002 (Julian 127) at 9:27PM Alaska Standard Time ice breakup occurred [13, 14]. The following graph is the 86 year history of the Nenama Ice Classic. Dates are plotted in Julian days to compensate for Leap Years which would advance breakup by one day if the Gregorian metric were used (compare 1940 to 1998 for example).

The most newsworthy item about this year's result was that all six winners were from Alaska [14]. Obviously the out-of-state gamblers took Dr. Sagarin's advice while the native Alaskan's exhibited better judgment. How does the "warmest winter on record" compare with other years, when viewed through the results of the Nenana Ice Classic? If we make the major assumption that earlier ice breakups are indicative of warming and later breakups of cooling, then the winter of 2001-2002 was cooler then average for the last 86 years. Here is what the actual data look like:



Gregorian Date

Time (AST)



2002 Breakup May 07, 2002




2001 Breakup May 08, 2001




Earliest Breakup Apr 20, 1998




2nd Earliest Breakup Apr 20, 1940




2nd Latest Breakup May 16, 1945




Latest Breakup May 21, 1964




Average Breakup May 05



Median Breakup May 05




 So what is the significance of the Nenana Ice Classic Proxy? As is the case with most Phenology Proxies, the real answer is probably: not very much. Just as tree rings measure cellulous formation during the growing season and leaf emergence measures prevailing spring temperature and precipitation conditions, the Nenana Ice Classic is measuring the time of ice breakup on the Tanana River at Nenana Alaska, during a 32 day period from late April to late May; nothing more and nothing less. Many events will affect ice breakup, including ice thickness, air temperature, water temperature, water levels and flow rates.  To conjecture that a log of the Nenana Ice Classic will prove or disprove the existence of global warming, or global cooling for that matter, is  idle speculation with absolutely no basis in fact. This is not to imply that Phenology is without value. Provided the data are accurate, evaluated objectively and their limitations are clearly understood, they can be of great scientific value. The problem with Phenology is that it is now being used advance a political agenda rather than a scientific one.  Of course, if the Global Warmers were to publish the full data as illustrated above, they would be due an apology, but on their past record is seems doubtful that one will be needed. 


Miceal O'Ronain

 (edited by jeb)

1.         "Nenana Ice Classic"

2.         " Climate Change in Nontraditional Data Sets", R. Sagarin and F. Micheli, Science 294, 811 (2001)

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

4.         "Alaskan gambling contest gives climate scientists accurate data"

5.         " Nenana ice lottery lends unique insight Researchers use contest records to study changing climate"

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

7.         " The Nenana Ice Classic: Betting on Warming"

8.         "2001: Second warmest year globally since records began"

9.         "Record Warm Winter In Much Of Midwest And Northeast"

10.       "What happened to spring?"

11.       "April continues to be the cruellest month",1413,113%257E7246%257E582105,00.html

12.       "Nenana Ice Classic ticket holders can see open water"

13.       "Six winners share Nenana Ice Classic's $304,000 jackpot"  

14.       "Watch Ice Melt, Win Big"