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Fifteen Hundred Years of Precipitation in the Ukraine
Solomina, O., Davi, N., D'Arrigo, R. and Jacoby, G.  2005.  Tree-ring reconstruction of Crimean drought and lake chronology correction.  Geophysical Research Letters 32: L19704, doi:10.1029/2005GL023335.

What was done
The authors present the first tree-ring reconstruction of spring (April-July) precipitation for the Crimean peninsula, located on the northern coast of the Black Sea in the Ukraine, for the period 1620-2002.  They then utilize this tree-ring chronology to correctly date and correlate with an earlier precipitation reconstruction derived from a sediment core taken in 1931 from nearby Saki Lake, thus ending up with a proxy precipitation record for this region that stretches all the way back to AD 500.

What was learned
According to the authors, no trend in precipitation was evident in an instrumental record obtained at a location adjacent to the tree-sampling site over the period 1896-1988.  Also, reconstructed precipitation values from the tree-ring series revealed year to year and decadal variation, but remained "near-average with relatively few extreme values" from about the middle 1700s to the early 1800s and again since about 1920.  The most notable anomaly of the 1500-year reconstruction was an "extremely wet" period that occurred between AD 1050 and 1250, which Solomina et al. describe as broadly coinciding with the Medieval Warm Epoch, when humidity was higher than during the instrumental era.

What it means
The results of this analysis demonstrate there was nothing unusual nor unique about spring precipitation on the Crimean peninsula over the last few decades of the 20th century, during which time climate alarmists claim the planet experienced unprecedented climate change due to CO2-induced global warming.  Instead, spring precipitation has chugged along for at least the past eight decades near its long-term mean, with little deviation or variability beyond that experienced at earlier times in the record.  And even if spring precipitation begins to rise in the future, say to levels akin to those experienced during the Medieval Warm Period, such a development would not provide proof of CO2-induced global warming, for if such precipitation levels have occurred before, at much lower-than-current CO2 concentrations, they can surely occur again ... naturally.

Davis, C.H., Li, Y., McConnell, J.R., Frey, M.M. and Hanna, E.  2005.  Snowfall-driven growth in East Antarctic Ice Sheet mitigates recent sea-level rise.  Sciencexpress/

Rignot, E. and Thomas, R.H.  2002.  Mass balance of polar ice sheets.  Science 297: 1502-1506.

Reviewed 7 December 2005