In a recent study, scientists from the University of Edinburgh and Biomathematics & Statistics Scotland used the data gathered by the Marsham family, and weather data gathered from the Central England temperature (CET) record, and evaluated the effect of temperature on fourteen species. The study found that while all species will leaf and flower sooner after experiencing a warmer spring, a warm autumn will affect some early season leafing trees, such as birch, as compared to the later season leafing trees, like oak. This effect may be due to certain species' chilling requirements and it is predicted that if seasonal temperatures continue to increase, oak may come into leafing earlier than birch over time.
|river birch (Betula nigra) by T. Davis Sydnor, The Ohio State University, Bugwood.org|
The unfortunate reality is that most data becomes lost or forgotten after the project ends. Citizen science programs can be very useful in that new people can be continually added to the project and the data collecting can live on through new membership. Citizen science programs similar to the work that the Marsham family did for so long exist in Project Budburst, Nature's Notebook, the National Phenology Network and many other projects.
For more on the study: Family log of spring's arrival helps predict climate-driven change
For more about Robert Marsham: Robert Marsham and Robert Marsham: The father of springtime records
For more information and a list of Citizen Science Programs: Scientific American - Citizen Science