Plant phenological fingerprints

Given the sensitivity of plant phenology to small changes in temperature and the fact that this relationship is universally understood by politicians and the general public it has been widely used in recent years as an indicator of anthropogenically driven climate warming. The timing of plant life-cycle events particularly in spring, in a range of different environments and locations across the world has clearly demonstrated an advance attributable to global warming. Here, a review of trends in direct observations of the response of plant phenology to warming is presented together with a comparison with other methods of landscape level phenological observations such as remote sensing. In addition, the need for meaningful correlations between satellite data and in situ phenological observations is highlighted.