The contrails are back. An odd thing to notice because it's so every day an occurrence it's the aerial equivalent of white notice.

Not seen, paradoxically, until they're not there, which has been the case for the past six days or so with the continent wide embargo placed on all air traffic.

There's been none of the periodic sonic shudders that rumble over my part of West London as the planes begin their approach into Heathrow. Nor have I been able to drift into that idle habit of mine when I'm stood at the bus stop counting the planes queuing up to land.

I wonder what positive things will come out of this six day plane free pause. After all, every reaction has an equal and opposite reaction, so we know what we've missed - simply getting home for many - but there has to be something positive out of this. Perhaps, as a friend said to me last night, it might encourage Kenyan farmers to stop growing roses and being dependant the whims of an entirely foreign market and instead grow crops that actually benefit them.

If, of course, life was only that easy and not bashed around by other realities - poverty, economics. Still, I wonder what positives will spin out of this six day pause.