The evidence is clear cut that when soil moisture is low late spring into summer, the atmosphere tends to be drier, often supporting stronger than normal pressure and therefore warmer temperatures. The opposite occurs when soils are wet.
Each and every spring, I closely monitor rainfall distribution through particularly March, April and May but also cannot ignore the previous winter’s rainfall pattern when it comes to producing a summer forecast.
As for other parameters, in particular El Nino, I believe this phenomenon plays a bigger role here in the UK never mind Europe than many scientists believe.
In 2012, we came off a dry back end to winter and beginning of spring. This falsely led me into believing a dry, warm summer was on the way. I couldn’t have been more wrong as 2012 was one of our wettest. Why? El Nino! I looked too closely at the dry spring pattern but failed to see the El Nino coming on. It appears that when ONCOMING El Nino’s occur during the spring months, this leads to a wetter summer.
However, El Nino can also aid in drier, warmer UK summers and following a warm, dry summer in 2013, an ALREADY established El Nino which perhaps weakened then re-intensified into early summer 2014, led to another prolonged period of impressive warm, dry weather.
There is of course more than just soil moisture and the ENSO but indeed the MJO and of course SST anomalies. Over the next few weeks, I will share thoughts on where we’re at and where I believe our summer is going this year… Will been issuing my summer forecast on May 1st.
I wish to share this interesting piece by Stuart Markham which explains another look at moisture content, relating to moisture content. This time, not in soil but tree bark…
Scientists expect HEATWAVE SUMMER for the UK!!!
By Stuart Markham of chorleyweather.com
Climate scientists are claiming that this summer will perhaps be one of the hottest and sunniest the UK has seen for some time, with temperatures regularly in their late twenties and thirties, for a sustained period through Summer. This claim along with other teleconnections such as a QBO flip and a developing El Nino just add further depth to their claims.
Climate scientists have for some time now, been measuring moisture in tree bark during the spring months to gain an advantage in weather prediction. In 2007, 2008, 2009 tree bark across the UK showed significantly high moisture levels and consequently those summers where indeed very wet, with major flooding in some areas. Furthermore in 2013 the moisture levels were significantly drier and not surprisingly that summer was largely drier, particularly through June and July.
This project which the scientists have named ‘Barking’ has been kept under wraps for quite some time. They first started the project in 1995, firstly as a way of researching global warming but it soon became clear there was a significant correlation between the bark moisture and summer weather. Professor Rolf Pailo explains ‘We initially started out using tree bark to measure global warming, as of course trees are significantly affected by more co2 in the atmosphere’.
He adds ‘after 5 years we started to see a correlation between moisture levels and the resulting summer weather, more moisture in the bark correlates to wetter summer months and drier bark correlates with drier summers’. He also states that ‘we have kept these results under wraps for over 20 years as we felt this time period would add further weight to our findings and will also help get our project peer reviewed’.
Professor Pailo has released this years results so far and the findings are rather stark. Moisture levels so far this year have been incredibly dry, in fact the driest they have recorded since the records began. Professor Pailo thinks these findings are incredibly significant and predicts not only a drought period through summer but he also states that the highest recorded UK temperatures will be attained quite easily this year given that global temperatures are already running well above average, figures below show global temperatures already 0.5c above 1981-2010 climatology.