1) There appears to be a negative correlation between the tree ring growth and the average temperature for each year. As the temperature declines the average tree ring growth becomes much more substantial and vice versa when the temperature increases. Examples of this correlation can be seen at several yearly intervals such as:

High Tree ring Growth, Low Temperature

1956 (Tree ring growth: 4.004) (Average temperature: -4.92)

1963 (Tree ring growth: 4.946) (Average temperature: -5.80)

1964 (Tree ring growth: 5.196) (Average temperature: -4.29)

1965 (Tree ring growth: 5.676) (Average temperature: -4.85)

1966 (Tree ring growth: 5.282) (Average temperature: -5.29)

High Temperature, Low Tree ring Growth

1977 (Average temperature: -0.86)(Tree ring growth: 1.234)

1981 (Average temperature: -0.87)(Tree ring growth: 0.728)

1987 (Average temperature: -0.83)(Tree ring growth: 2.18)

1988 (Average temperature: -0.66)(Tree ring growth: 1.582)

2) Based on the information gathered and graphed from question #1, tree growth during a warm year would be minimal. During a cold year a more normalized tree ring growth would occur and during a very cold year, tree ring growth would be the most substantial.

3) For the most part, between the years 1950-1994 there is a positive correlation between the amount of annual precipitation and tree ring growth. More annual precipitation (in.) creates a greater tree ring growth, which is confirmed by the essential role that water plays in the process of photosynthesis and tree growth.  Examples of this correlation can be seen at several yearly intervals such as:

High Average Annual Precipitation, High Tree ring Growth

1963 (Average Annual Precipitation: 35.65)(Tree ring growth: 4.946)

1967 (Average Annual Precipitation: 43.56)(Tree ring growth: 4.116)

1971 (Average Annual Precipitation: 36.17)(Tree ring growth: 3.7)

Low Average Annual Precipitation, Low Tree ring Growth

1958 (Average Annual Precipitation: 15.44)(Tree ring growth: 1.218)

1974 (Average Annual Precipitation: 16.87)(Tree ring growth: 1.29)

1976 (Average Annual Precipitation: 17.55)(Tree ring growth: 1.59)



The years with the best growth were 1962-1968, with the greatest tree ring growth in 1965. During these years there were relatively high levels of annual precipitation and lower than average temperatures. The years with the lowest growth were 1977-1982, with the lowest tree ring growth in 1981; during these years, there were favorable levels of precipitation, however the highest temperatures of the measured time period.

5) The recent trends that can be easily observed from the graphs are:

–          Average annual precipitation is experiencing less dry seasons and more consistent years of heavy annual precipitation.

–          Average temperature is becoming consistently much higher.

–          Average tree ring growth is becoming consistently much lower; not near the minimal values but tree ring growth no longer experiences periods of excessive growth and values only range between 1.5-3.5mm of annual growth.

6) Based on these trends, one would expect to see higher levels of precipitation, higher average temperature and lower tree ring growth for the year 2010. If conditions are not altered then it can be expected that these conditions will only be more hyperbolic by the year 2050.

7) This experimental data provides the classic bases for the evidence of global warming. The Alaskan region is experiencing more humid average temperatures as a result of global warming which is resulting reduced snowfall and heavier precipitation each year. This is consequently causing a reduction in average tree ring growth per annum because the optimal conditions are no longer available. This residual warming can be attributed to green house gas accumulation and increased sun exposure.

author avatar
William Anderson (Schoolworkhelper Editorial Team)
William completed his Bachelor of Science and Master of Arts in 2013. He current serves as a lecturer, tutor and freelance writer. In his spare time, he enjoys reading, walking his dog and parasailing. Article last reviewed: 2022 | St. Rosemary Institution © 2010-2024 | Creative Commons 4.0

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