Biologically‐Relevant Trends in Springtime Temperatures Across the United States
AffiliationUniv Arizona, Dept Environm Sci
Univ Arizona, Sch Nat Resources & Environm
MetadataShow full item record
PublisherAMER GEOPHYSICAL UNION
CitationCrimmins, T. M., & Crimmins, M. A. (2019). Biologically‐relevant trends in spring time temperatures across the United States. Geophysical Research Letters, 46, 12,377–12,387. https://doi.org/10.1029/2019GL085251
JournalGEOPHYSICAL RESEARCH LETTERS
RightsCopyright © 2019. American Geophysical Union. All Rights Reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractLong‐term trends in temperature—a primary driver of phenology—are typically evaluated using monthly or seasonal averages. However, accumulated warmth, rather than average temperature, cues phenological events; further, the amount of heat necessary to trigger activity is species‐specific. We evaluated trends in the timing of three heat accumulation thresholds encompassing spring‐season biological activity in the conterminous United States over a 70‐year period to document changes from a biologically relevant perspective. The Southwest, Northeast, and Northwest regions exhibit the strongest advancements. Rates of change vary among thresholds within many regions, resulting in temporal compression and lengthening within the season. Further, in the Eastern United States, the days between when a single threshold is met in the south and north are decreasing; in the West, the opposite pattern is occurring. These trends generally match long‐term observations of species' phenology, underscoring the value of this approach for documenting biologically relevant changes in temperature.
Note6 month embargo; published online: 6 November 2019
VersionFinal published version
SponsorsNational Science FoundationNational Science Foundation (NSF) [DBI-0735191, DBI-1265383]; 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