In a state of “pre-emergencia”
On Friday, a state of Pre-emergencia was called in Santiago as a result of exceedingly high levels of ozone, little wind and no rain. It has not rained since Easter Day (more or less)…. and at this time of the year there is little prevailing wind from the south west, so the air just sits in or slowly circulates in “the bowl” that is Santiago. While we enjoy sunning ourselves and the air warms to a very pleasant 22-26C every day (and they call this autumn?!!), the emissions from industry and vehicles are gradually being converted to poisonous air that we all breathe.
So Santiaguinos are desperately hoping it will rain this week. Hoping for rain? Doesn’t sound like Autumn to me!
The Government here has some seriously neat tactics to deal with the problem. The state of pre-emergency restricts vehicles with registration plates ending with specific numbers from driving in the city during the day. This includes trucks. In addition, you must have a “green tag” indicating your car has a catalytic convertor (2001 onwards). You can get fined almost £200 for driving your car on the wrong day! Today 3-5 and 7-8 can’t drive. I don’t think there are any registrations ending with zeros.
Now that really is zero-tolerance!
May 23rd, 2006 at 10:16 pm
Hummmmm…. that would be SMOG, not OZONE levels that are high Doug - ie pollutants have exceeded the “Good/Clear/Bad/Critical/are you breathing yet??? levels
May 24th, 2006 at 12:43 am
Ermmm… I don’t remember much from my CSYS Geography course or my masters in Geography, but I’m remarkably certain (or arrogantly stubborn) of my knowledge of the chemical composition of photo-chemical smog…..
Basic smog is just a mixture of smoke and sulphur dioxide- the classic “pea souper” in London caused by excessive coal burning is one example.
But photo-chemical smog is produced by a reaction of solar radiation with nitrous oxides (NOx’s), some organic compounds or higher altitude ozone. In santiago we have the worst of everything. Photo-chemical smog (NOxs produced by cars), but also temperature inversion, which results in low-level ozone levels increasing. And worse still, particulate levels are very high in santiago due to high and inefficient diesel engine emissions.
I’m very relieved that the rain has brought down the particulates… i’m breathing again!
May 31st, 2006 at 7:43 pm
You’re forgetting that the rain brings forth water, that mixes with dirt, which goes all muddy, that when it dries goes all dusty, and then buses, trucks, cars and taxis (independent of diesel engines) throw all the particles back in the air, and then the rain comes… and the rain brings forth water, that mixes….