CLIMATE RECONSTRUCTION FOR NORTHEAST OHIO DROUGHT USING QUERCUS ALBA L. TREE-RINGS

The hot and dry June and July of 2012 emphasizes the need to understand drought in the Midwest where most of North America’s corn and soybeans are grown. Old growth white oaks (Quercus alba L.) in Northeast Ohio have proven to be sensitive records for climate variability, specifically variations in summer precipitation and temperature. The goal of this study was to reconstruct drought using these moisture sensitive tree-rings. Living old growth and beams from historical structures are combined to create a tree ring chronology of 683 ring-width series that spans AD 1550 to 2012. This chronology is compared with monthly meteorological records from 1888 to the present that shows a strong positive correlation with June and July precipitation and negative relationship with June temperature, making it particularly sensitive to summer drought. One of the narrowest rings in the series is 1894, the driest summer (growing season) on record when June and July precipitation totaled only 81 mm, compared to a yearly average of about 195 mm and had a Palmer Drought Severity Index (PDSI) between -2 and -3. This established drought sensitive terrestrial record can then be used to reconstruct moisture variability through the Little Ice Age – contemporary warming transition as well as through the dramatic changes in land use associated with settlement during the early decades of the 19^th century. This new comprehensive tree-ring series provides a longer-term context for Ohio drought back to the 16^th century and can be incorporated into larger-scale drought reconstructions that seek to map the spatial character and evolution of drought across North America.