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[[Robert Marsham]] is the founding father of modern phenological recording. Marsham was a wealthy landowner who kept systematic records of "Indications of spring" on his estate at [[Stratton Strawless]], [[نورفولك]], from 1736. These were in the form of dates of the first occurrence of events such as flowering, bud burst, emergence or flight of an insect. Consistent records of the same events or "phenophases" were maintained by generations of the same family over unprecedentedly long periods of time, eventually ending with the death of Mary Marsham in 1958, so that trends can be observed and related to long-term climate records. The data show significant variation in dates which broadly correspond with warm and cold years. Between 1850 and 1950 a long-term trend of gradual climate warming is observable, and during this same period the Marsham record of oak leafing dates tended to become earlier.<ref name="Sparks & Carey">{{Cite journal| last1 = Sparks | first1 = T.H. | last2 = Carey | first2 = P.D. | year = 1995 | title = The responses of species to climate over two centuries: an analysis of the Marsham phenological record, 1736-1947 | url = | journal = Journal of Ecology | volume = 83 | issue = 2| pages = 321–329 | doi = 10.2307/2261570 }}</ref>
 
After 1960 the rate of warming accelerated, and this is mirrored by increasing earliness of oak leafing, recorded in the data collected by Jean Combes in Surrey. Over the past 250 years, the first leafing date of oak appears to have advanced by about 8 days, corresponding to overall warming on the order of 1.5&nbsp;°C in the same period.
 
Towards the end of the 19th century the recording of the appearance and development of plants and animals became a national pastime, and between 1891 and 1948 a programme of phenological recording was organised across the British Isles by the [[Royal Meteorological Society]] (RMS). Up to 600 observers submitted returns in some years, with numbers averaging a few hundred. During this period 11 main plant phenophases were consistently recorded over the 58 years from 1891–1948, and a further 14 phenophases were recorded for the 20 years between 1929 and 1948. The returns were summarised each year in the Quarterly Journal of the RMS as ''[[The Phenological Reports]]''. The 58-year data have been summarised by Jeffree (1960),<ref name=Jeffree1960>{{Cite journal| last1 = Jeffree | first1 = E.P. | year = 1960 | title = Some long-term means from the Phenological reports (1891–1948) of the Royal Meteorological Society | url = | journal = Quarterly Journal of the Royal Meteorological Society | volume = 86 | issue = 367| pages = 95–103 | doi = 10.1002/qj.49708636710 |bibcode = 1960QJRMS..86...95J }}</ref> and show that flowering dates could be as many as 21 days early and as many as 34 days late, with extreme earliness greatest in summer flowering species, and extreme lateness in spring flowering species. In all 25 species, the timings of all phenological events are significantly related to temperature,<ref name=Sparks2000>{{Cite journal| last1 = Sparks | first1 = T.H. | last2 = Jeffree | first2 = E.P. | last3 = Jeffree | first3 = C.E. | author-separator =, | author-name-separator= | year = 2000 | title = An examination of the relationship between flowering times and temperature at the national scale using long-term phenological records from the UK | url = | journal = International Journal of Biometeorology | volume = 44 | issue = 2| pages = 82–87 | doi = 10.1007/s004840000049 | pmid = 10993562 |bibcode = 2000IJBm...44...82S }}</ref><ref>[https://springerlink3.metapress.com/content/trx39rutgulmbmwn/resource-secured/?target=fulltext.pdf&sid=w4lgorijbyuqsz552uo5bbqb&sh=www.springerlink.com SpringerLink - Abstract<!-- Bot generated title -->]</ref> indicating that phenological events are likely to get earlier as climate warms.
: <math>\mathrm{NDVI}={\mathrm{NIR}-\mathrm{red} \over \mathrm{NIR}+\mathrm{red}}</math>
 
[[Imageملف:MODIS NDVI Temporal Profile Conifer.jpg|thumb|400px|NDVI temporal profile for a typical patch of coniferous forest over a period of six years. This temporal profile depicts the growing season every year as well as changes in this profile from year to year due to climatic and other constraints. Data and graph are based on the [[MODIS]] sensor standard public vegetation index product.<ref>[http://tbrs.arizona.edu/cdrom/Index.html Tbrs, Modis Vi Cd-Rom<!-- Bot generated title -->]</ref> Data archived at the [[مختبر أوك ردج الوطني]] DAAC [http://daac.ornl.gov/], courtesy of Dr. Robert Cook.<ref>[http://daac.ornl.gov/articles/DAAC_Annual/From_the_Ground_Up.pdf 49971CU_Txt<!-- Bot generated title -->]</ref> ]]
 
The evolution of the vegetation index through time, depicted by the graph above, exhibits a strong [[ارتباط (إحصاء)]] with the typical green vegetation growth stages (emergence, vigor/growth, maturity, and harvest/senescence). These temporal curves are analyzed to extract useful parameters about the vegetation growing season (start of season, end of season, length of [[موسم زراعة]], etc.). Other growing season [[وسيط (رياضيات)]]s could potentially be extracted, and global maps of any of these growing season parameters could then be constructed and used in all sorts of [[تغير المناخ]] studies.
 
[[تصنيف:ظواهر دورية]]
[[Categoryتصنيف:Chronobiology]]
[[تصنيف:علم البيئة]]
[[تصنيف:علم المناخ]]
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