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# Archived Accumulated Growing Degree Average and Anomaly Products (1981-2010 climate normal)

Preferred citation (DataCite format):

  USA National Phenology Network (2022).
  Archived Accumulated Growing Degree Average and Anomaly Products (1981-2010 climate normal).
  University of Arizona Research Data Repository.
  Dataset. https://doi.org/10.25422/azu.data.19027415


Corresponding Author:
  Alyssa H Rosemartin, USA National Phenology Network/SNRE, ahouse@email.arizona.edu


License:
  CC BY 4.0


DOI:
  https://doi.org/10.25422/azu.data.19027415



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## Summary

Heat accumulation is commonly used as a way of predicting the timing of
phenological transitions in plants and animals. The USA National Phenology
Network (USA-NPN) hosts a suite of accumulated growing degree day products to
serve a number of audiences. In 2022, the USA NPN updated all long-term
average and anomaly products in this suite to use the more recent climate
normal period (1991-2020).

This record contains the archived layers that use the prior normal
(1981-2010). The data consists of geotiff rasters with daily accumulated
growing degree day values. The "average" files show the daily GDD value
averaged across 1981-2010. The "anomaly" files show for each day 2016-2021,
the difference between that day's accumulation and the long term average.
These products begin accumulation on January 1 and use either a 32F or 50F
base temperature.

The products using updated normals can be accessed here: [Accumulated Growing
Degree Days, Continental United States, 1981 - Current
Year](https://arizona.figshare.com/articles/dataset/Accumulated_Growing_Degree_Days_Continental_United_States_1981_-_Current_Year/14270531)



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## Files and Folders

The agdd.zip contains two subfolders: 
1) avg_agdd, which is the long term average daily growing degree value, using base 32 Fahrenheit and 
2) agdd_anomaly which has the daily anomalies for 2016-01-01 through 2021-12-31, using base 50 Fahrenheit.

The agdd_50f.zip contains two subfolders: 
1) avg_agdd_50f, which is the long term average daily growing degree value, using base 50 Fahrenheit and 
2) agdd_anomaly_50f which has the daily anomalies for 2016-01-01 through 2021-12-31, using base 50 Fahrenheit.



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## Materials & Methods

Please see the USA National Phenology Network gridded products documentation report for full details on the development of this data product:

Crimmins, T.M., Marsh, R.L., Switzer, J.R., Crimmins, M.A., Gerst, K.L., Rosemartin, A.H., 
and Weltzin, J.F., 2017, USA National Phenology Network gridded products documentation:
U.S. Geological Survey Open-File Report 2017–1003, 27 p., https://doi.org/10.3133/ofr20171003. 



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## Contributor Roles

The roles are defined by the CRediT taxonomy http://credit.niso.org/

  - Michael Crimmins, University of Arizona, Conceptualization, Data Curation, Methodology, Visualization
  - Theresa Crimmins, University of Arizona, Conceptualization, Data Curation, Methodology, Visualization
  - Katharine Gerst, University of Arizona, Conceptualization, Data Curation, Methodology, Visualization
  - Lee Marsh, University of Arizona, Conceptualization, Data Curation, Methodology, Visualization
  - Alyssa Rosemartin, University of Arizona, Conceptualization, Data Curation, Methodology, Visualization
  - Jeff Switzer, University of Arizona, Conceptualization, Data Curation, Methodology, Visualization
  - Jake Weltzin, US Geological Survey, Conceptualization, Data Curation, Methodology, Visualization



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## Additional Notes

Links:
  - https://doi.org/10.25422/azu.data.14270531