Wednesday 8th July
I have today included a picture of a baby puffin taken on Skomer Island, which is called a puffling.
Tuesday began the new day with variable cloud that meant the rise in temperature was restricted during the first half off the morning, nevertheless, by 13.22 the heatwave threshold had been reached with a maximum of 29.9C at 16.51, which was 7.0C above my long-term average. The UV level at its peak was again Very High. The heat was slow to drain away overnight, however a low of 14.1C was logged at 05.36 early Wednesday, just after sunrise in Marlborough at 05.00, being 2.1C above average.
There was no thin cloud to minimise the strong sunshine at the start of Wednesday that resulted in a temperature of 22.9C by 08.00, which made it the warmest start to a new day at that time since 26th June. As the area of high pressure slowly changes the breeze today will be variable and light starting off with a northerly aspect before backing to have a more westerly component. The barometric pressure has begun to rise again with a reading of 1020.7mb at 08.00.
The past few days have seen minima above average but not so high as during the previous heatwave. The forecast is for this situation to continue for another week at least with at the moment, no possibility of tropical nights ahead, when the temperature does not drop below 20C.
The Azores ridge of high pressure is slowly edging northwards that will see its centre move to be between Scotland and Iceland by Saturday, which by then will see the air steam have a more easterly component, which will result in maxima drop a few degrees below the peak on Friday, but still in heatwave territory.
Yesterday I added paragraphs about the ‘cold blob’ in the North Atlantic. This was raising concerns amongst climate scientists and how it might affect the Atlantic Meridional Overturning Circulation (AMOC). Some more research adds detail to the recent concerns.
The AMOC is one of the two main engines of global circulation, which is why it is so important, as it brings warm Caribbean water towards the north. It emits that heat to the atmosphere and keeps us relatively warm here in Europe, before that water sinks and heads southwards.
I understand there are indications that the current system appears to have slowed down or changed – hence the cold blob.
Because the cold blob is so big it also affects the air above it. The jet stream, which we know has a major influence on our weather being a fast flowing current of air flowing from west to east, hits the cold blob and is forced to go around it. The result, I understand, is heat dumps and cold snaps, where it hits the bottom and then creates a wave in the jet stream that passes over Europe.
Much more research is needed to discover if the AMOC is slowing or changing but in the shorter term it is suggested that the cold blob could lead to more heatwaves in the UK, however, in the longer term there is the potential for the climate in northern Europe to get much colder due to the blob.