Wednesday, 27 June 2012

Summary of the last weeks

First of all, apologies for not updating this blog sooner. The last weeks have been filled with almost non-stop flying. When the instruments did not need flight preparations, calibrations or other maintenance, the scientists used every available minute to prepare quick-look-data, so the next flights could be planned based on the days observations.
To give an overview of what has been done so far, the past days are summarized individually below.


On Thursday the 14th of June, the weather finally allowed for a start of the transfer flights. On this day, the airship was moved to Wels (AT) from Friedrichshafen (DE). The cabin layout used for the 14th and all other transfer flight days is the photochemistry centered CL8.


On Friday, the Zeppelin flew from Wels (AT) to Gorizia (IT/SI). To be able to make this big distance around the Alps, it was agreed upon that no scientific operator would be on board for this flight.
Of course, this situation worried the scientists a bit, but all instruments ran without problems throughout the flight.



On Saturday, there was a technical problem with the Airship. It was thought that this would prevent any flight for that day, but the Zeppelin employees worked on the problem swiftly and had the broken part replaced by noon. The Zeppelin was then flying across the adriatic sea and arrived at the local airport in Ozzano (IT) at 6 pm. This airport is serving as the base of operations for all flights during the 2012 Po-Valley phase of the PEGASOS field campaign. The scientists were welcomed by the bolognese institute ISAC-CNR for a kick-off-meeting. In this meeting, the available ground-based measurement sites and the instrumentation available on the Zeppelin were presented to an interested scientific audience. Also, procedures and lines of communications for the coordination of the measurements were established.



Sunday was reserved for maintenance on the instruments and on the airship.



On Monday, still having the photochemistry package on board, we decided to do height profiles at St. Pietro Capofiume (SPC), where a supersite (english description here) of ISAC-CNR is located. To characterize the chemical composition of the atmosphere during breaking up of the nocturnal boundary layer, the flight started at 4:50 am and ended at 11:30 am. By ending the flight at this time, we also preserved the instruments from damage by the extreme temperatures of 36°C in the shade (reached in the early afternoon) and much higher in the light.
In the evening, the slightly cooler temperatures were used to change the cabin layout to the nucleation-centered CL9.
CNR supersite in St. Pietro Capofiume


In the days before Tuesday, the researchers at the SPC supersite observed new particle formation events almost every day. So for the 19th, the Zeppelin flew to SPC with the freshly installed CL9 package to explore the vertical extent of nucleation. The results of this day are still under discussion, also at the ground site there was no very clear nucleation observed.
On this day, the Zeppelin was accompanied by the mobile laboratory MOSQUITA of the swiss PSI institute. The evening was again used for a cabin layout change to the secondary organic aerosol package CL5
MOSQUITA mobile laboratory



On Wednesday, the CL5 package flew to SPC for height profiling. Interestingly, a clearly different evolution of aerosol composition in time has been observed for the different altitudes, until the differences disappeared at around 1 pm.

Nitrate concentration evolving over time, datapoints coloured by altitude.



On Thursday, still operating CL5, the Zeppelin did transects between the northwest an the southeast, going as deep into the valleys of the Apennines as buoyancy and thermal activity allowed. For this day, the chemical weather forecast predicted a plume of polluted air being transported from the east of the Po-valley to the west, through relatively clean air brought in over the Apennines. Judging from quick-look data, this plume was existent and has been cut into with the Zeppelin several times.



On Friday, the Zeppelin flew with the CL5 cabin layout towards the adriatic sea via SPC and back again. To our surprise, we did not see a big difference between land and sea with most instruments. The NOx instrument did see an increase in NO2 at the coastline, which can probably be attributed to the highways there. The Zeppelin started at 6 am and returned at 10:30 am. In the afternoon, there was a press conference to inform the local media about the project.


After nine days of almost non-stop action, scientists and Zeppelin crew retreated to a well earned day off on saturday.


On Sunday, the airship left Ozzano at 9 am, flying past SPC and to the adriatic sea once more. From there, a few transects to the east-nordeast were flown, exploring the variability of atmospheric compositon and aging of airmasses. The airship returned at around 3 pm, most instruments on the verge of shutting down due to too high temperatures. In the evening, the cabin layout was changed to the photochemistry package CL8.



On Monday, the photchemistry package was used to investigate the atmospheric composition at Bologna and its downwind region on that day. The flights included going up in the valleys of the Apennines again.



There were thunderstorms with rain predicted for Tuesday afternoon. Weather like this decreases the condensational sink, thereby increasing the likelihood for new particle formation events. With that in mind, the cabin layout was changed to the nucleation package CL9 in the morning.


Today, the nucleation package left for the SPC supersite in the early morning. There, the Zeppelin flew circles in different heights. Ground based measurements at SPC seem to indicate a nucleation event, so we are all excited to find out about the results of the Zeppelin-based measurements at different altitudes.

Tuesday, 12 June 2012

Transfer to Italy - update

After two weeks in Friedrichshafen, the Zeppelin and the scientists are now eager to get moving to Po valley in Italy. There, we will have the longest part of our 2012 campaign.
Unfortunately, weather with heavy rain prohibits flights at the moment. As there is a high pressure area expected to be inbound, we are hoping for a start on wednesday afternoon/thursday morning from Friedrichshafen.

Depending on exact weather conditions, the flight will lead to Wels (AT), or Graz (AT) directly.
The goal is then to make it to Gorizia (IT/SI) or even Ozzano (IT) directly on Friday.

Make sure to check out the Zeppelin location on our tracker if you are planning to see the airship fly!