Indicator Specification

Plant and fungi phenology

Indicator Specification
  Indicator codes: CLIM 023
Published 20 Nov 2012 Last modified 20 Dec 2016
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Trends in spring phenology

Assessment versions

Published (reviewed and quality assured)
  • No published assessments


Justification for indicator selection

Phenology is the timing of seasonal events such as budburst, flowering, dormancy, migration and hibernation. Some phenological responses are triggered by mean temperature, while others are more responsive to day length or weather extremes. Changes in phenology affect the growing season and thus ecosystem functioning and productivity. Changes in phenology are impacting farming, forestry, gardening and wildlife. The timing of tilling, sowing and harvesting is changing, fruit is ripening earlier due to warmer summer temperatures, and grass in municipal parks and on road verges requires more frequent cutting over a longer period. Changes in flowering have implications for the timing and intensity of the pollen season and related health effects. The pollen season is advancing as many species start to flower earlier, and the concentration of pollen in the air is increasing. The increasing trend in the yearly amount of airborne pollen for many taxa is more pronounced in urban than semi-natural areas across the continent.

Scientific references

Indicator definition

  • Trends in spring phenology


  • days/year

Policy context and targets

Context description

In April 2013 the European Commission presented the EU Adaptation Strategy Package ( This package consists of the EU Strategy on adaptation to climate change /* COM/2013/0216 final */ and a number of supporting documents. One of the objectives of the EU Adaptation Strategy is Better informed decision-making, which should occur through Bridging the knowledge gap and Further developing Climate-ADAPT as the ‘one-stop shop’ for adaptation information in Europe. Further objectives include Promoting action by Member States and Climate-proofing EU action: promoting adaptation in key vulnerable sectors. Many EU Member States have already taken action, such as by adopting national adaptation strategies, and several have also prepared action plans on climate change adaptation.

The European Commission and the European Environment Agency have developed the European Climate Adaptation Platform (Climate-ADAPT, to share knowledge on observed and projected climate change and its impacts on environmental and social systems and on human health; on relevant research; on EU, national and subnational adaptation strategies and plans; and on adaptation case studies.


No targets have been specified.

Related policy documents

  • Climate-ADAPT: Adaptation in EU policy sectors
    Overview of EU sector policies in which mainstreaming of adaptation to climate change is ongoing or explored
  • Climate-ADAPT: Country profiles
    Overview of activities of EEA member countries in preparing, developing and implementing adaptation strategies
  • DG CLIMA: Adaptation to climate change
    Adaptation means anticipating the adverse effects of climate change and taking appropriate action to prevent or minimise the damage they can cause, or taking advantage of opportunities that may arise. It has been shown that well planned, early adaptation action saves money and lives in the future. This web portal provides information on all adaptation activities of the European Commission.
  • EU Adaptation Strategy Package
    In April 2013, the European Commission adopted an EU strategy on adaptation to climate change, which has been welcomed by the EU Member States. The strategy aims to make Europe more climate-resilient. By taking a coherent approach and providing for improved coordination, it enhances the preparedness and capacity of all governance levels to respond to the impacts of climate change.

Key policy question

How is climate change affecting the seasonal cycle of plants and fungi in Europe?



Methodology for indicator calculation

A phenological dataset collected during the COST 725 Action ‘Establishing a European phenological data platform for climatological applications’ was analysed, which contained more than 36000 phenological time series for Europe covering 1971–2000.

Methodology for gap filling

Not applicable

Methodology references


Data specifications

EEA data references

  • No datasets have been specified here.

External data references

Data sources in latest figures



Methodology uncertainty

Not applicable

Data sets uncertainty

Generally, observations for popular groups such as vascular plants, birds, other terrestrial vertebrates and butterflies are much better than for less conspicuous and less popular species. Similarly, due to extensive existing networks, a long tradition and better means of detection and rapid responses of the organisms to changes, knowledge on phenological changes are better observed and recorded than range shifts. Projections of climate change impacts on phenology rely crucially on the understanding of current processes and responses. For most cases, only a few years of data are available and do not cover the entire area of the EU but are restricted to certain well monitored countries with a long tradition in the involvement of citizen scientists. Based on these short time series, the determination of impacts and their interpretation thus has to rely on assumptions, and achieving a qualitative understanding of species’ responses is more robust than their quantification. One of the greatest unknowns is how quickly and closely species will alter their phenology in accordance to a changing climatic regime. Even experimental studies seem to be of little help, since they notoriously tend to underestimate the effects of climate change on changes in phenology.

Further information on uncertainties is provided in Section 1.7 of the EEA report on Climate change, impacts, and vulnerability in Europe 2012 (

Rationale uncertainty

No uncertainty has been specified

Further work

Short term work

Work specified here requires to be completed within 1 year from now.

Long term work

Work specified here will require more than 1 year (from now) to be completed.

General metadata

Responsibility and ownership

EEA Contact Info

Hans-Martin Füssel


European Environment Agency (EEA)


Indicator code
CLIM 023
Version id: 2

Frequency of updates

Updates are scheduled every 4 years


DPSIR: Impact
Typology: Descriptive indicator (Type A - What is happening to the environment and to humans?)


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