Meta-analysis of warming experiments

The Synthesis of Timings Observed in iNcrease Experiments (STONE) database includes data from over 37 warming experiments focused explicitly on assessing phenological change with temperature increases. To find these studies we searched the Web of Science (ISI) for Topic=(warm* OR temperature*) AND Topic=(plant* AND phenolog*) AND Topic=(experiment* OR manip*) in November 2009 and examined all 401 records, updating results through December 2010. To obtain the most accurate data we contacted authors, requesting access to their data (receiving 16.7% of data directly) then extracted phenological event dates and magnitude of warming data from the papers if authors could not share data. Studies conducted in distinctly different areas or habitats presented in one paper were each treated as individual sites. We compared all data once extracted and removed data that appeared to be duplicated (e.g., a publication would use data from 1994-1996 and another 1996-1999, if the data were identical we included the 1996 data only once), but we did not combine studies that appeared to be conducted at the same field site unless they specifically stated they were from the identical experiment. We generally extracted data for all treatments reported (e.g., several studies had additional snow or precipitation treatments) but found we had only sufficient data on temperature treatments for comparisons and analyses. We extracted all phenological data across all events (leafing, flowering and fruiting)