The Earth's climate is changing largely due to human activities. Average temperatures have significantly increased compared to pre-industrial levels and the World Meteorological Organization declared 2015-2019 as the warmest five-year period on record.
Climate change has an impact on the life cycle of plants and animals, but this impact is not easy to discover because also the seasonal weather affects plant and animal life. Despite that, collections of phenological data, i.e. long-term records of the date in which a plant/animal reached a certain development stage, are becoming increasing relevant in the study of climate change.
In this repository you will find code for the analysis of the plant phenology data related to Germany and available in the database of the Pan-European Phenology Project. An interactive map of the German phenological stations is in output/images/phenology_stations_map.html.
The analysis focuses on the data available for winter barley. Linear regression models suggest that the growing season of winter barley has shortened in recent years and the barley harvest is beginning earlier according to the calendar. Although the overall trend is recognisable, more refined analyses are difficult in this case because:
- the data do not contain information on the plant varieties and whether they are consistent over time within and across stations;
- there is no weather information (average temperature, sunlight, etc.) that can help to isolate the seasonal weather from the climate trend.