Growing degree days (GDD) is the measure of how much warmth is available for plant and insect growth during a growing season. GDD information helps horticulturists and farmers predict plant growth and stock development. The GDD value changes in response to climate variations, such as El Niño. Long-term changes in GDD are a measure of changing climate conditions.
Further information can be found in:
Tait, A, Macara, G, & Paul, V. (2014) Preparation of climate datasets for the 2015 Environmental Synthesis Report: Temperature, Rainfall, Wind, Sunshine and Soil Moisture. Prepared for Ministry for the Environment. Available at https://data.mfe.govt.nz/x/Fwn9AL on the Ministry for the Environment dataservice (https://data.mfe.govt.nz/).
This dataset relates to the "Growing degree days" measure on the Environmental Indicators, Te taiao Aotearoa website.