Mark Hunt weather corner; 118 - 2024; A reflection as turf managers
I think it is a good time to reflect on 2024 and the year we endured from a weather perspective as turf managers.
As a basis for this discussion, I collated data from a Davis weather station located in Wheathampstead, Hertsfordshire.
First up is their monthly rainfall compared to the local 30-year average;
Now, I have discussed rainfall and rainfall patterns quite a bit this year, but I won’t apologise for doing so again, because it has been such an unpredictable one from this perspective. I mean, just look at the variability between monthly rainfall and the the Met Office 1991-2020 yearly average! There have been 4 months when we had over double the 30-year average and one (September) when it was quadruple! The excessive variability in our climate from a rainfall perspective is plain to see.
Is this a trend though, can we say that? I don’t think so because for it to be a clearly-defined trend, we would have to have a consistent pattern of weather responsible for it, and there’s the rub. For example, September’s monumental figure was the result of a cut-off low pressure system that wandered over from central Europe, gained potential from the Bay of Biscay and then slowly moved across the south of England (and Midlands) depositing three times the monthly average rainfall in just 2 -3 days. Predicting the formation and ‘behaviour’ of these cut-off low pressure systems is a meteorological challenge and one where I think we are playing catch up.
Here are some more interesting stats from the same weather station…..
If we look at the maximum rain rate recorded during the month in column 2, we can see that we have some pretty ‘fruity’ rain rates in July, September, October and December. Part of the reason for this, I believe, is due to low pressure systems tracking across warmer-than-average seas and gathering energy and the potential to deposit more rainfall in the process. From a practical perspective, if you conduct infiltration rates, these are the current levels your surfaces (and infrastructure) need to cope with.
Moving along, we received nearly 95% more moisture from rainfall than had been lost from the soil and plant by evapotranspiration (E.T). It is normally 40%, so this particular turf manager has had to deal with significantly wetter surfaces in 2024.
Growth-wise, as denoted by G.P (Growth Potential), the start to the year was dire with January to April contributing only 15% of the total yearly growth, but 36% of the yearly rainfall. Recovery from the ravages of the 23/24 autumn/winter was hard to come by, as was some dry days.
Of course, growth peaked in July and August, but a very wet July meant that higher-height-of-cut areas just kept growing rather than slowing down as they experienced lower soil moisture levels. That summer growth flush continued into September and October with only November showing a cool down. More cutting means more wear and tear on machinery, more man hours and more fuel used.
Finally, I added up all the daily Smith Kerns Probability totals to see which month had the most significant disease pressure (I could have averaged the month as well, but I found the cumulative figure more interesting). So the highest disease pressure month using this somewhat unorthodox measurement? September, with big peaks in activity of Microdochium nivale and Clarireedia homeocarpa (Dollar Spot) at the beginning and end of the month.*
So, turf managers, that was 2024. Sit back and give yourselves and your team a pat on the back for coping with it. It was, without doubt, a tough one!
www.weatherstations.co.uk
Send your questions for Mark to: editor@pitchcare.com
*There was no Smith Kerns data for December because the air temperatures were below the model parameters, but there was significant disease pressure over the christmas week!