Big freezes are now predictable, says Met Office!

A new study published today (Friday 14 September) in Environmental Research Letters, compares the latest seasonal forecast system to the one previously used [1]. The conclusion is that the latest models can better warn the UK of extreme winter weather conditions.

The winter of 2009–2010 was known as “The Big Freeze” here in the UK and was part of the severe winter weather in Europe. It was the coldest winter since 1978-79, with a mean temperature of 1.5 °C.

winter

Picture of the UK taken on the 7th January 2010.

The new model takes into account sudden stratospheric warmings (SSWs), which are known to be responsible for cold surface conditions. SSWs happen when the polar vortex of westerly (eastward) winds in the winter hemisphere suddenly slows down or even reverses direction, accompanied by a rise of stratospheric temperature by several tens of kelvins.

References

[1] D R Fereday, A Maidens, A Arribas, A A Scaife and J R Knight. Seasonal forecasts of northern hemisphere winter 2009/10. (2012) Environ. Res. Lett. 7 034031

Links

IOP News

UK universities have student places left

Apparently about a quarter the UK Russell Group Universities still have undergraduate student places, as the new tuition fees regime comes in.

…it is likely fewer people will go to university this year.

Higher Education Minister David Willetts

UCAS say that there are more than 26,000 university courses with empty places, compared with 20,000 at this time last year.

Links

BBC News

Pictures of atomic bonds from IBM in Zurich

A team at IBM in Zurich have used a variant of a technique called atomic force microscopy to produce single-molecule images [1]. These are so detailed that the type of atomic bonds can be seen.

Here are some of those pictures. They belong to IBM and can be found on the BBC website.

pic1

The bonds at centre are shorter than those at the edges, as they involve more electrons.

pic2

The same team imaged olympicene.

References

[1] Gross et al. Bond-Order Discrimination by Atomic Force Microscopy. Science 14 September 2012:
Vol. 337 no. 6100 pp. 1326-1329

Witten on supermanifolds and integration on them

Edward Witten placed some notes on the arXiv on 11th September entitled “Notes On Supermanifolds and Integration” [1]. In the notes he outlines the the theory of supermanifolds and integration on them. His motivation is to present what is needed for the RNS formalism in string theory.

Witten

Edward Witten

As ever Witten has produced very readable and concise notes without over complicating things. I recommend that anyone interested in how to integrate objects on supermanifolds start here.

References

[1] Edward Witten. Notes On Supermanifolds and Integration. arXiv:1209.2199 [hep-th]