Future Scenarios Tool User Case 4
How might the date of first fall freeze change in the future and what are the implications for vinifera grape production in Michigan?
Vinifera (grapes) benefit from an extended freeze-free fall season. A later date of first fall freeze in the vinifera-growing regions of Michigan will enhance production.
To see how the date of first fall freeze may change in the future at Maple City, first select from the input page of the Future Scenarios Tool “Agriculture”, “Temperature”, “Growing Season Statistics”, and “Median Date of First Fall Freeze”. (See Screenshot 1 below)
Screenshot 1
Click on “View Result”. This display for the 1981-2000 reference climate indicates considerable year-to-year variability in the date of first fall freeze at Maple City with a median date of September 28. (Screenshot 2)
Screenshot 2
When choosing the “Mid vs. Late Century” display, uncertainty surrounding the projected changes can be seen from the spread of the bars in the histogram (Screenshot 3). Some of the scenarios suggest fairly large changes in the median date of first fall freeze (up to 20 days later than at present for the mid-century scenarios and close to 35 days later than present for the late-century scenarios). On the other hand some scenarios suggest little or no change in the date of first fall freeze. However, the majority of the scenarios suggest a later freeze date and hence improved conditions for vinifera grapes.
Screenshot 3
