Dormancy to Budburst: Extreme Lows

During the winter, winegrapes enter the dormancy stage of their seasonal lifecycle. As the air temperature cools throughout the winter months, the risk of injury from extreme cold increases. A useful metric to account for the risk of cold injury is the minimum daily temperatures that the plants may experience. 

The projected minimum temperature anomalies (meaning difference from historical values) between December to March are displayed below. Following that, we also show the mean minimum daily temperature anomalies for March and then for April, all for the Okanagan Valley of British Columbia, Canada.

The maps below have three tabs, each shows the same information but allows you to visualize it in a slightly different way. 

    • One the first tab (Interactive) you can zoom in and out. Importantly you can see the warming scenarios by clicking on the small square showing three layers in the upper right corner of the map; for best viewing we recommend checking only one box at a time of the three options (Historical, Moderate warming, High warming). This box also lets you change the underlying map (basic topographic or  imagery, which gives satellite views).
    • The middle tab (Compare Warming Scenarios) shows the historical, moderate warming and high warming scenarios side-by-side for easy comparison.
    • The right tab (Anomalies) shows how much of a change occurs from the recent (historical) past versus the moderate (MW) and high (HW) warming scenarios. 
More information about these maps can be found below, here. 

Minimum Temperatures: December to March

Mean Minimum Daily Temperatures: March

Mean Minimum Daily Temperatures: April

More Information

Anomalies:
Anomalies are a metric which highlight the change in a variable (minimum temperature, for example) from the recent historical average (1970 – 1989). Positive values indicate a projected increase from the past. For example, a value of -2 would mean temperatures will be two degrees cooler than the historical average, while a value of 2 would be two degrees warmer than the historical average. 

Warming Scenarios:
Two warming scenarios are represented in the data. The Moderate Warming (MW) and High Warming (HW) scenarios are represented by averaging the data for the periods of years between 2040 – 2059 and 2070 – 2089, respectively. These warming scenarios represent two instances in the spectrum of potential climate realizations.
These warming scenarios represent projected future climate based on a high emissions scenario at two timepoints in the future. For more information on the climate scenarios see, About.

Average Anomalies (Warming Scenario – Historical):

    • Minimum Temperature:
      • December to March: historical average temperature is -6.5 °C, with warming temperatures rise:
          • Moderate Warming: 4.9 °C
          • High Warming: 7.1 °C
    • Mean Minimum Daily Temperature:
      • March: historical average temperature is -1.0 °C, with warming temperatures rise:
          • Moderate Warming: 5.0 °C
          • High Warming: 7.7 °C
      • April: historical average temperature is 2.2 °C, with warming temperatures rise:
          • Moderate Warming: 4.6 °C
          • High Warming: 7.4 °C