Thursday 28^th February

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Weather Outlook:

Flight plan for tomorrow: Down day – no flight. A bus tour of Andøya is planned instead.

Blog

The unpredictability of the Arctic weather is the reason that we are here, but it is also one of the greatest challenges to our operations here. The pilots weren’t too happy at the end of the 9am briefing this morning, when they saw that the flight plan that they had filed with air traffic control had again changed somewhat overnight. The changes were due to a change in the forecasts for today, which were noticed this morning, and the flight plan adjusted accordingly. Idar and Jon Egill had to call air traffic control at Bodø, Gardemøen (Oslo), Reykjavik and Sondestrom (Greenland) to get the changes approved at such short notice, but happily they were obliging and take-off was set for midday local time.

Gudmund had managed to secure clearance for the foreign visitors such as myself to be escorted through the military airbase to our research aircraft. We had to leave before the rocket range closed the road to Andenes in preparation for a rocket launch at 11am, which meant that we missed seeing the rocket launch, but hopefully they will launch some more rockets while we’re here. It was interesting to take a close look at the DLR aircraft. It is very different to the FAAM aircraft. It’s much smaller, and very cramped inside, with 2 LIDARs and other instruments and only room for the scientists that operate them. We got to see them prepare the aircraft and tow it outside, before it powered up its engines and disappeared along the longest runway in Norway, before coming back past us airborne and off on their mission. For some photos of the plane, and the spectacular scenery behind it, see the link on the Fieldwork page.

The problem with the dropsonde data, if anyone is following that story, was sorted last night in a combined effort between us meteorologists, dropsonde technician Reinhold and the creator of the program that we’re using to process the raw dropsonde data and send it onto the GTS. Unfortunately for Reinhold, who releases the dropsondes from the aircraft and transmits the data, the only fix that we could come up with was to open each dropsonde data file and remove several lines of data where there was missing data (lat, long) after launch before opening this amended data file into Aspen to send it to Met Norway. The problem is caused by the DLR not having its aircraft data system linked to the dropsonde system, so when the program which processes the dropsonde data looks for the latitude and longitude of the aircraft at the time the sonde was released it can’t find it, and enters zero. The above description is mainly a note for myself, I realise that no-one else is interested in these details!

We are having a down day tomorrow, as there’s not much interesting weather for us to fly and observe, and Gudmund has organized a bus tour of Andøya and a neighbouring island that is connected to Andøya by a bridge. For it to be a proper rest day for the air crew tomorrow, they can’t do any work including flight planning and so we are flight planning Saturday’s flight today. It is going to be a flight across the Finnmark coast to capture some gravity waves (hopefully with the LIDAR if there isn’t too much cloud) and then up over Svalbard to map the tropopause fold associated with a PV anomaly. The aircraft is likely to land in Spitsbergen where the temperature is -21°C (!!!) and spend the night there. This makes sense because Sunday’s flight is likely to also be in the Spitsbergen area, so we save fuel and aircraft hours by staying there overnight instead of flying back and forth. As I’m writing this (at 6pm) the 12Z run of the 4km UM for a small area including Spitsbergen has just come in and Idar is very excited by the appearance of a polar low on Saturday. Whether it will remain in the forecast and materialize in real life remains to be seen – like I said earlier, the weather here is hard to predict!

We were enjoying out Bakala (dried salted cod with vegetables and potatoes in a tomato sauce) with flatbrød (flatbread) when Andreas Dörnbrack from DLR came in to tell us some bad news: one of the LIDARs is broken and instead of having a down day tomorrow, some of the crew will have to work to try and fix it. This means that we might run into problems with our plans for flights on Saturday/Sunday, as the crew have to have a rest day soon. More on this tomorrow…

Weather Round-up

There is a tropopause fold associated with an upper-level PV anomaly moving over the front south of Spitsbergen and distorts the front as it moves. The PV anomaly will be over Spitsbergen on Saturday and moves west of Spitsbergen on Sunday.

The cold-air outbreak is evident on the surface charts from 00Z on Saturday, and becomes stronger and the flow more northerly into Monday. The polar lows predicted to be east and west of Spitsbergen on Monday have disappeared from the forecast. There is now a larger low pressure system, forming at the southern end of a front stretching from the west of Spitsbergen south towards Norway, which moves away from the coast of Norway by 12z on Tues 4^th March.

SAP Evaluation

The ETKF SAPs put the maximum in sensitivity to the north of Norway again, just west of Svalbard for all optimization times. Again, this is probably due to the high baroclinicity in this region.

There is predicted to be a low pressure system just SW of Iceland tomorrow at targeting time. The SV SAPs pick out the leading edge of the low pressure system at 12hrs optimization time, as well as the northern edge of the system at later optimization times. There is strong upper level flow into the verification region from these sensitive regions.