Season creep

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Cherry blossoms in Japan have been emerging earlier in recent years due to climate change TakiZakura2012Apr29(SakuraLooksWaterfall-MiharuFukushimaJapan).jpg
Cherry blossoms in Japan have been emerging earlier in recent years due to climate change
Changes in pollen season in the United States, 1995 to 2013. Changes in Pollen Season (14113640520).png
Changes in pollen season in the United States, 1995 to 2013.

In phenology, season creep refers to observed changes in the timing of the seasons, [1] [2] such as earlier indications of spring [3] widely observed in temperate areas across the Northern Hemisphere. [4] [5] Phenological records analyzed by climate scientists have shown significant temporal trends in the observed time of seasonal events, [6] [7] from the end of the 20th century and continuing into the 21st century. [5] [8] In Europe, season creep has been associated with the arrival of spring moving up by approximately one week in a recent 30-year period. [9] [10] Other studies have put the rate of season creep measured by plant phenology in the range of 2–3 days per decade advancement in spring, and 0.3–1.6 days per decade delay in autumn, over the past 30–80 years. [11]

Contents

Observable changes in nature related to season creep include birds laying their eggs earlier and buds appearing on some trees in late winter. [12] In addition to advanced budding, flowering trees have been blooming earlier, for example the culturally-important cherry blossoms in Japan, [13] [14] and Washington, D.C. [15] [16] [17] Northern hardwood forests have been trending toward leafing out sooner, and retaining their green canopies longer. [18] The agricultural growing season has also expanded by 10–20 days over the last few decades. [19]

The effects of season creep have been noted by non-scientists as well, including gardeners who have advanced their spring planting times, [20] and experimented with plantings of less hardy warmer climate varieties of non-native plants. [21] While summer growing seasons are expanding, winters are getting warmer and shorter, resulting in reduced winter ice cover on bodies of water, [22] earlier ice-out, [23] earlier melt water flows, [24] and earlier spring lake level peaks. [25] Some spring events, or "phenophases", have become intermittent or unobservable; for example, bodies of water that once froze regularly most winters now freeze less frequently, [8] [26] [27] and formerly migratory birds are now seen year-round in some areas. [28]

Relationship to global warming

The American Robin has ceased to migrate in some areas American Robin (23225302456).jpg
The American Robin has ceased to migrate in some areas

The full impact of global warming is forecast to happen in the future, but climate scientists have cited season creep as an easily observable effect of climate change [29] that has already occurred and continues to occur. [5] [12] [19] [30] A large systematic phenological examination of data on 542 plant species in 21 European countries from 1971–2000 showed that 78% of all leafing, flowering, and fruiting records advanced while only 3% were significantly delayed, and these observations were consistent with measurements of observed warming. [10] [31] Similar changes in the phenology of plants and animals are occurring across marine, freshwater, and terrestrial groups studied, and these changes are also consistent with the expected impact of global warming. [32]

While phenology fairly consistently points to an earlier spring across temperate regions of North America, a recent comprehensive study of the subarctic showed greater variability in the timing of green-up, with some areas advancing, and some having no discernible trend over a recent 44-year period. [33] Another 40 year phenological study in China found greater warming over that period in the more northerly sites studied, with sites experiencing cooling mostly in the south, indicating that the temperature variation with latitude is decreasing there. [34] This study also confirmed that season creep was correlated with warming, but the effect is non-linear—phenophases advanced less with greater warming, and retarded more with greater cooling. [34]

Shorter winters and longer growing seasons may appear to be a benefit to society from global warming, but the effects of advanced phenophases may also have serious consequences for human populations. Modeling of snowmelt predicted that warming of 3 to 5 °C in the Western United States could cause snowmelt-driven runoff to occur as much as two months earlier, with profound effects on hydroelectricity, land use, agriculture, and water management. [35] Since 1980, earlier snowmelt and associated warming has also been associated with an increase in length and severity of the wildfire season there. [36]

Season creep may also have adverse effects on plant species as well. Earlier flowering could occur before pollinators such as honey bees become active, which would have negative consequences for pollination and reproduction. [17] Shorter and warmer winters may affect other environmental adaptations including cold hardening of trees, which could result in frost damage during more severe winters. [17]

Etymology

Season creep was included in the 9th edition of the Collins English Dictionary published in London June 4, 2007. [37] [38] The term was popularized in the media after the report titled "Season Creep: How Global Warming Is Already Affecting The World Around Us" was published by the American environmental organization Clear the Air on March 21, 2006. [39] In the "Season Creep" report, Jonathan Banks, Policy Director for Clear the Air, introduced the term as follows:

While to some, an early arrival of spring may sound good, an imbalance in the ecosystem can wreak havoc. Natural processes like flowers blooming, birds nesting, insects emerging, and ice melting are triggered in large part by temperature. As temperatures increase globally, the delicately balanced system begins to fall into ecological disarray. We call this season creep. [39]

See also

Other uses

The term "season creep" has been applied in other contexts as well:

Related Research Articles

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<span class="mw-page-title-main">Global cooling</span> Discredited 1970s hypothesis of imminent cooling of the Earth

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<span class="mw-page-title-main">Meadow</span> Open habitat vegetated primarily by non-woody plants

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<span class="mw-page-title-main">Arctic sea ice decline</span> Sea ice loss observed in recent decades in the Arctic Ocean

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<span class="mw-page-title-main">Climate change in Antarctica</span> Impacts of climate change on Antarctica

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The Plant Phenology Ontology (PPO) is a collection of OBO Foundry ontologies that facilitate integration of heterogeneous data about seed plant phenology from various sources. These data sources include observations networks, such as the National Ecological Observatory Network (NEON), the National Phenology Network (NPN), and the Pan-European Phenology Database (PEP725), remote sensing, herbarium specimens, and citizen science observations. The initial focus during ontology development was to capture phenological data about one plant or a population of plants as observed by a person, and this enabled integration of data across disparate observation network sources. Because phenological scorings vary in their methods and reporting, this allows these data to be aggregated and compared. Changes in plant phenology can be linked to different climate factors depending on the species, such precipitation or growing degree days. Aggregated data about the timing of plant life cycle stages at different places and times can provide information about spatiotemporal patterns within and among species, and potentially offer insight into how plants may change or shift their life cycles in response to climate change. These shifts can have implications for agriculture and various biodiversity research avenues, such as shifts in pollinator and host life cycles.

<span class="mw-page-title-main">Climate change and birds</span>

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Traditional Phenological Knowledge can be seen as a "subset of Indigenous Knowledge". Traditional Phenological Knowledge (TPK) is the knowledge based on traditional observations made by Indigenous Peoples that predict seasonal changes of nature and their immediate environment. This can be useful for the management of naturally occurring phenomenon, as well as "adaptive management" such as fire management. TPK is not a novel practice and has been practised for hundreds of years. TPK encompasses history, observations and Traditional Knowledge(TK) or Indigenous Knowledge (IK). Indigenous Knowledge is flexible and always evolves. It considers the past, present and future of environmental and biological generations.

References

  1. Gabay, Jonathan (2006). "23. So What's New?". Gabay's Copywriters' Compendium (Second Edition: The Definitive Professional Writers Guide ed.). Oxford: Butterworth-Heinemann. pp.  701. ISBN   978-0-7506-8320-3. Season creep n. Earlier spring weather and other gradual seasonal shifts caused by global climate change.
  2. 1 2 Maxwell, Kerry (18 September 2006). "Macmillan English Dictionary Word Of The Week Archive - "Christmas creep"". New Words. Macmillan Publishers. Archived from the original on 20 March 2007. Retrieved 26 December 2007. ...season creep, earlier spring weather and seasonal shifts caused by global climate change
  3. Maxwell, Kerry (December 2007). "A review of 2007 in twelve words". MED Magazine. Macmillan English Dictionaries. Retrieved 23 December 2007. It's a classic case of the newly identified phenomenon of season creep, where Winters are warmer and Spring arrives earlier.
  4. Schwartz, M. D.; Ahas, R.; Aasa, A. (2006). "Onset of spring starting earlier across the Northern Hemisphere". Global Change Biology. 12 (2): 343–351. Bibcode:2006GCBio..12..343S. doi:10.1111/j.1365-2486.2005.01097.x. S2CID   86329402. SI first leaf dates, measuring change in the start of 'early spring' (roughly the time of shrub budburst and lawn first greening), are getting earlier in nearly all parts of the Northern Hemisphere. The average rate of change over the 1955–2002 period is approximately -1.2 days per decade.
  5. 1 2 3 Cleland, E.E.; Chiariello, N.R.; Loarie, S.R.; Mooney, H.A.; Field, C.B. (2006). "Diverse responses of phenology to global changes in a grassland ecosystem". Proceedings of the National Academy of Sciences. 103 (37): 13740–4. Bibcode:2006PNAS..10313740C. doi: 10.1073/pnas.0600815103 . PMC   1560087 . PMID   16954189. Shifting plant phenology (i.e., timing of flowering and other developmental events) in recent decades establishes that species and ecosystems are already responding to global environmental change. Earlier flowering and an extended period of active plant growth across much of the northern hemisphere have been interpreted as responses to warming.
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  12. 1 2 "Man bags at ten paces? Just look it up". Scotsman.com News. 4 June 2007. Retrieved 23 December 2007. While the full impact of global warming is still to be experienced, many scientists are warning that it is responsible for earlier springs leading to longer summers.
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  17. 1 2 3 Chung, Uran; Mack, Liz; Yun, Jin I.; Kim, Soo-Hyung (2011). Harvey, Jeffrey A (ed.). "Predicting the Timing of Cherry Blossoms in Washington, DC and Mid-Atlantic States in Response to Climate Change". PLoS ONE . 6 (11): e27439. Bibcode:2011PLoSO...627439C. doi: 10.1371/journal.pone.0027439 . PMC   3210174 . PMID   22087317. The expected changes in phenology will have a substantial effect on the reproduction, distribution and productivity of trees as the coincidence of ecosystem processes, such as flowering and the emergence of pollinators, is disrupted. Some plants may also become less resistant to environmental challenges. For example, shorter and warmer winters can reduce the cold hardening of trees, leaving them vulnerable to frost injury.
  18. Richardson, A.D.; Bailey, A.S.; Denny, E.G.; Martin, C.W.; O'Keefe, J. (2006). "Phenology of a northern hardwood forest canopy". Global Change Biology. 12 (7): 1174–1188. Bibcode:2006GCBio..12.1174R. CiteSeerX   10.1.1.495.6146 . doi:10.1111/j.1365-2486.2006.01164.x. S2CID   10717334. ...significant trends (P≤0.05) towards an earlier spring (e.g. sugar maple, rate of change=0.18 days earlier/yr), consistent with other studies documenting measurable climate change effects on the onset of spring in both North America and Europe. Our results also suggest that green canopy duration has increased by about 10 days (e.g. sugar maple, rate of change=0.21 days longer/yr) over the period of study.
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  25. "Early risers". New Scientist. 167 (2241): 21. 3 June 2000. Retrieved 27 December 2007. North America's Great Lakes are reaching their spring high-water levels a month earlier than they did when records began in 1860. Levels normally rise in the spring as snow melts, but regional temperatures have been rising for the past 90 years, and winter ice cover has been shrinking.
  26. Wake, Cameron (4 December 2006). "Climate Change in the Northeast: Past, Present, and Future" (PDF). Climate Change in the Hudson Valley, NY. Retrieved 27 December 2007. A particularly interesting lake ice record comes from Lake Champlain where they record the ice in date.... Of more significance is the fact that the ice has not frozen in the area of observation in 16 of the past 30 years.
  27. "Why Less Winter Ice is the Pitts for State". The Detroit Free Press . 3 April 2006. Retrieved 23 December 2007. Grand Traverse Bay ... froze at least seven winters out of every 10; the rate slipped in the 1980s. In the 1990s, the bay froze only three times. So far this decade, once. Observers see that as one more sign of what some call "season creep," or evidence of global warming.
  28. "Report warns of global warming increase". Portsmouth Herald. Retrieved 27 December 2007. ...Jan Pendlebury, executive director of the New Hampshire chapter of the National Environmental Trust, said... 'Global warming is forcing changes to the quintessential indicator that spring has arrived: return of the robin. Recent years have documentation that rather than flying south with other feathered friends, many populations of robins are becoming year-round residents, not only in the southern tier of the state, but as far north as Jackson.'[ permanent dead link ]
  29. Shifting Distribution of Northern Hemisphere Summer Temperature Anomalies, 1951-2011 on YouTube NASA published on May 17, 2013
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  38. "'Season creep', 'BBQ stopper' appear in dictionary pages". ABC News Online . 4 June 2007. Retrieved 23 December 2007. "Hoodies", "season creep" and "barbecue stopper" are among hundreds of new words and phrases included in an updated version of an English dictionary.
  39. 1 2 "Season creep". Word Spy. Retrieved 23 December 2007. Earliest Citation:… Jonathan Banks, 'Season Creep: How Global Warming Is Already Affecting The World Around Us,' National Environment Trust, March 21, 2006
  40. "What Has Longer Season Brought To Baseball Besides Snow Warnings?". Seattle Post-Intelligencer (Seattle, WA). 23 October 1997. Archived from the original on 16 May 2011. Retrieved 26 December 2007. Call it season creep. First came the shift to 162 games, a change that made it, among other things, impossible to compare Roger Maris' 61 home runs to Babe Ruth's 60.
  41. "Virginian-Pilot Archives". The Virginian-Pilot . Pilot Media. 29 May 2007. Retrieved 26 December 2007. 'Season creep' has expanded the time an intercollegiate athlete must devote to his or her specialty. No sport should be year-round or nearly so.
  42. Sellnow, Greg (7 April 2007). "Greg Sellnow column: I'm just sayin'". Post-Bulletin, Rochester, Minn. Retrieved 26 December 2007. And it is money, of course, that is responsible for campaign season creep. If you don't raise money early -- gobs and gobs of it -- you'll find yourself on the fundraising super highway with roller marks over your body, where your opponent's war chest plowed over you.
  43. Siewers, Alf (25 November 1987). "He's well-suited to enjoying life of Santa". Chicago Sun-Times . Retrieved 26 December 2007. And so does the culture, with a commercializing of himself that Santa deplores even as he has watched the holiday season creep back to Labor Day.