Sources of δ18O Concentration Variability in Greenland Ice Cores: Temperature, North Atlantic Oscillation and Solar Activity

This work concerns possible connection between variations of δ¹⁸O in Greenland ice, temperature, precipitation amount, NAO indices and relative sunspot numbers. The relationships between 10-year averaged values of this data were derived making use of regression analysis methods. It was discovered that February temperature yields the main contribution in variability of δ¹⁸O. The multiple correlation coefficient between weighted night temperature of the most important months and δ¹⁸O equals 0.95±0.01. Besides the local source of δ¹⁸O changes, defined by the amount of precipitation and temperature, an additional source correlated with the level of solar activity has been revealed. The relative contribution of this source in the δ¹⁸O variance is about 0.1. It has been shown that the multiple correlation coefficient between δ¹⁸O and NAO indices is equal to 0.85. Therefore the NAO yields more than 2/3 of the variances of climatic change in Greenland. An independent contribution of solar activity in climatic changes is about 1/3.