Does an Early Spring Indicate an Early Summer? Relationships Between Intraseasonal Growing Degree Day Thresholds

National Oceanic and Atmospheric Administration's Regional Integrated Sciences and Assessments (RISA) program [NA17OAR4310288]; Climate Assessment for the Southwest program at the University of Arizona; National Science FoundationNational Science Foundation (NSF) [DBI-0735191, DBI-1265383]