Frost Risk

As part of my research I will be looking at frost risk in relation to the establishment of Sitka spruce plantations in Ireland. I will be doing this by taking certain weather stations throughout Ireland who have gathered temperature data for their region since the 1960’s. It has been shown that Ireland’s temperature is rising and that the number of frost days are decreasing.

It is my hope that with this data I can establish the occurrence of frost days in each region by looking at temperatures below 0°C and calculating the frost risk in each region. This will allow for better planning with regards to tree plantation locations throughout Ireland and perhaps the introduction of new species.

I have found during my research that frost risk has been decreasing in Ireland from 1967 to 2017. The research looked at changes over 20 year periods with 10 year overlaps. What this means is that in many places there is an increased opportunity to introduce new tree species that are less tolerant to frost due to the decreasing risk of frost damage. Coastal regions have shown very low frost risk while mid-land regions have shown the highest frost risk. The current trends show that the risk of frost damage is decreasing in Ireland meaning more and more sites will be suitable for Sitka spruce establishment, particularly areas which were previously not suitable such as Bord na Móna cutaway bogs in the midlands.

The data gathered and results that were found were then used to help create forest climactic zones along with precipitation and mean annual temperature data for the previous 20 years. Below are images of the number of frost days for the periods 1967-87, 1977-97, 1987-07 and 1997-17. The results found that 1967-87 saw the highest number of frost days on average with the lowest recorded in the period 1997-17 and the maps reveals how frost risk has been declining since 1967 to present. You can also find a slideshow with graphs displaying the average number of frost days at each station over the periods examined on the Media page.