Earlywood and latewood: new insight on the tree growth-climate response in the U.S. Southwest with emphasis on the summer monsoon.

Earlywood and latewood tree-ring chronologies offer promise for reconstructing season- specific, and in some cases, dual-season climate variability. This was our motivation for developing a new network of 50 intra-annual chronologies for the southwestern U.S., where annual precipitation is split between the westerly influenced winter and summer monsoon climate regimes. This presentation reflects on our chronology development protocol, which was aimed at maximizing the monsoon signal available in individual latewood records through careful consideration of field sampling, specimen analysis, and time-series standardization. We describe some strengths and limitations of the new network through interpretation of its embedded seasonal climate signal and attempt to reconcile the tree-growth response to the region's dynamically independent precipitation regimes. These results are focused on the U.S. Southwest, but may be relevant for other regions where reconstructing season- specific climate from intra-annual tree-ring chronologies is a goal.