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Global Phenological Monitoring - GPM

Global Phenological Monitoring (GPM)

is an initiative of the commission "Phenology" of the International Society of Biometeorology (ISB).

The main objectives of GPM are:

  • To link 'local' phenological networks and to encourage establishment and expansion of phenological networks throughout the world, thus facilitate the comparability of dissimilar programmes and phases (works via the so-called "phenological calendar").
  • The furthering of co-operation between phenologists world-wide. At the same time, information on phenological research and data banks is to be collected and made available for research purposes.
  • To encourage research that correlates phenological trends with climatic trends, especially in the context of global change monitoring and to encourage research agricultural uses (such as crop/integrated pest management and timing of agricultural operations), and human health (pollen warnings).
  • To explore methods of using phenology to stimulate public interest, especially among pupils and students by setting up education programmes (e.g. the Canadian initiative "Plantwatch" or the GLOBE initiative "Budburst".

The occurrence dates of phenological phases are dependent on the environment conditions, e.g. soil type, soil moisture, and insolation. However, temperature has the greatest influence in medium latitudes with winter rest and vegetation activity in summer; this is especially true for the "early" phases, whereas it is not quite so pronounced in the autumnal phases. Nevertheless, one can speak of a dominance of temperature influences in these latitudes. That is why the determination of the temperature is the sole purpose. As the influence of temperature and precipitation may not be separated, irrigation yields clearer results. Consequently the objects observed are irrigated in case of water shortage. In order to obtain the exact date of the beginning of a phase, observations should be made at least 3-4 hours after the sun has passed zenith (midday).

A number of indicator species have been selected (see below) and grouped in two groups: a Standard Program and a Flowering Phase Program. Both programs together form the Maximum Program. The Standard Program consists of fruit species and the Flowering Phase Programm consists of ornamental shrubs and snowdrops.

Selection criteria of indicator species:

  • The timing of phenological events of the plants are clearly sensitive to climate, whereas temperature has the greatest influence.
  • For each climate type (cool, medium and warm), within the medium latitudes, three fruit species should be represented, whereby the cold-resistant and warm-loving species also can grow under the medium climate.
  • The timing of flowering of the plants selected should cover a substantial period of the year (almond blooms first, European chestnut last).
  • The fruit species had to be commonly used (wide-spread; apple, pear cherry).
  • The plants should have a large distribution and/or a broad ecological amplitude.

For more informations see:

     Bruns, E., Chmielewski, F.-M. & van Vliet, A.J.H. (2003): The global phenological
     monitoring concept. in: Schwartz, M. (ed.): Phenology: An Integrative Environmental 
, 93-104.