It was only a matter of time: yesterday morning CENAPRED (Mexico's National Centre for the Prevention of Disasters) raised the alert level on Popo from yellow phase 2 to 3. This is the third highest warning on the seven step scale.

The Mexican newspaper, La Jornada reported almost a week of 'high amplitude tremors, with persistent emission of ash and gas that reached over 3.5m above the crater.' Incandescent fragments rising up to a kilometre high issue from Popo at present, where our team stood 5,000m up back in February. I ponder this as I type to you from the safety of the terracotta 'womb' of our beloved Museum.

Popo during quieter times in February. Dave, Chiara and Hugo survey their impending climb.

Who best to contact than Chiara, who knows more than most about the psychology of this restless giant? Following the recent activity of volcanic tremors and earthquakes she explained that, 'In the last couple of weeks, the dome has been destroyed. The caldera [a cauldron like feature, formed by the land collapsing after an eruption] is full to the brim and the fear is that lava may begin to flow outside the rim.'

There are currently no plans to evacuate but she said, ' The area within which you cannot go has been extended. At least until we know which of the two scenarios will now happen.'  By this, Chiara refers to Popo returning to a normal level of activity or continuing this temptestuous episode.

A letter to Popo. If you're going to erupt, don't do it without me. 

'It's very hard to tell what will happen at the moment. Popo is a very dangerous volcano.' It's here that despite being on the telephone in another part of the Museum, I sense that smile crossing her lips. The one I remember from our fieldwork in Mexico in February. ' I sent an article about this to Dave last week,' she continues, 'I told him what we need to do right now. Is to go back ...'

Watch this space to see how things develop!