Orgu

Hello everybody! I found this forum early this winter and have followed it with great interest. Very enlightening posts, even for a professional meteorologist! Now, I want to bring some contribution on my own, and it is about whether SSW is leading the troposphere or the other way around. It seems to be to cut both ways. Last winter, I did some statistics for the temperature in Oslo before and after a SSW, and found the temperature to be lower than normal the first weeks, a notch towards normal 20-30 days after the SSW, and then a new dip 30-40 days after. This winter I did some statistics, including the period before the SSW, and dividing it in La Nina and El Nino winters, inspired by an artice I read recently, which was about the frequency of SSW, which was found to be equally frequent in El Nino as La Nina (less frequent in neutral). The results were surprising in more than one way. The temperature in La Nina winters were 50 days before SSW 2 degrees above normal (fits with the findings of a colder stratosphere in La Nina winters and as this winter have been), and in El Nino 2 degrees below normal. During the winter a SSW occured, and in La Nina the temperature sank- towards normal after the SSW, reaching normal in the end. In El Nino the temperature increased (!) during the winter, also after the SSW and also reached normal temperatures 30-40 days after SSW. Several articles describe tropospheric blockings as a precursor to SSW, with warming propagating upwards. There seems to be much discussion in this forum focusing on the downward propagation. I don't know the details, but I guess this has to do with wave 1 and wave 2 activity, where one of them is more connected to upward and the other downward, and also to the EP-flux through 60 degrees, where southward flux is connected to downward, and northward to upward. This winter therefore seems to have had more southward flux, associated with downward warming, but recently the charts has shown northward flux, associated with the blocking-tendency we have seen in several prognosis, which have been supported by the warming stratosphere. In El Nino winters the dynamics are totally different. My view on how to handle the stratosphere is that it goes hand in hand with the troposphere, but it should be handled carefully how they interact, and I still dont master the details. I would gladly present my excel-graphs but dont know how..