If you thought that the Coronavirus lockdown was all good news for climate change, maybe you’ll have to think again. If Covid-19 leads to a long term reduction in greenhouse gas emissions that would be great of course. But an article in Mongabay has looked at the possibility that the reduction in the cooling impact of sulphate aerosol emissions from industry, shipping and the like will accelerate atmospheric warming. This is because these emissions help in the formation of clouds and increase their reflectivity. Could it be that our glorious blue sky spring had something to do with the reduction in these aerosols? This year has also seen accelerated arctic warming. All related? Another conundrum for the scientists to ponder, and yet another excuse for climate deniers to persist with their delusions. There will always be counterintuitive consequences in something so complex as climate change, and in such circumstances the precautionary principle (a.k.a insurance) is the best one to stick with.