12th October 1999

Fifth Scientific Flight

The favourable extension of the polar vortex, whose northern edge was forecasted above the Cape Horn archipel and southern Tierra del Fuego, made possible to plan a flight exploiting the maximum available range of the aircraft deeply within the vortex. The direction chosen was 176 deg to the waypoint with coordinates 70.0 S, 65.5 W, the southernmost latitude reached during the whole campaign. The main goal of the flight was to study the recovery of the reactive chlorine into the reservoir species.
Take-off at 7.08 local time was followed by a fast climb to 17.5 km, from where the southbound leg was established ascending in two steps to 18 an 18.5 km. At the end of a 20 minutes dive down to 15 km and back, the turning point was reached and the aircraft headed back to Ushuaia. It was not possible to reach the agreed 19 km altitude because the temperatures dropped to about -85 degrees which caused changes in the operation of the engines. When the external temperature later increased, the aircraft ascended in steps to 20.2 km. The envisaged 20.5 km was only reached during the last 60 km when sufficient fuel had been used up. The descent was made according to the flight plan and the landing took place at 12.35 local time.
Almost all the experiments collected useful data during this deep south flight into the polar vortex.

8th October 1999

Fourth scientific flight

The fourth scientific flight was devoted to the study of the physical and chemical conditions within and without a filament migrating from the polar vortex trough the region between Tierra del Fuego and the Antarctic peninsula at an altitude between 14 and 18 Km.
The flight started at 03.32 LT heading towards a point at 62.0° S, 59.0° W, above the Southern Shetlands, and flying at an altitude of 14.3 Km. After a dive to 12 Km and a slow climb to 18.5 Km direction South, the aircraft reached 64.3° S, 59.0 W, above the southern end of the Trinity peninsula, and then turned right towards point 53.0° S, 62.5 W. Before the turning point and shortly after the pilot reported a noticeable air turbulence, ending after a quick climb to 18.7 Km; he observed also a distinct haziness, visible as a thin cloud under the aircraft after the exit from the turbulence. At the same time and for about 8 minutes, there was a sharp drop in temperature from -55° C down to about -65°C. Wile the results are only preliminary, several instruments on board detected small, short duration, signals pointing to the existence of a localized "thin cloud" in correspondence with the part of the aircraft trajectory above the Antarctic peninsula mountains.
During the subsequent slow descent in tree steps down to 18 Km, several instruments measured simultaneously a peculiar behavior in the concentration of various atmospheric constituents and tracers, to be attributed to the traversal of the filament.
At 53.0° S 62.5° W the aircraft performed a left round about turn to direction 50° descending slowly to 14.2 Km, at which height it turned on right directing towards Ushuaia landing at 09.09 LT.

2nd October 1999

3rd scientific flight:

The third scientific flight was devoted to the study of the microphysics and chemistry inside gravity waves generated in the upper atmosphere by the interaction of surface orographic discontinuities and strong winds at low altitudes (lee waves). The area between the Antarctic Peninsula and Tierra del Fuego was monitored for more than a week with local circulation models able to forecast the formation of lee waves. The forecast provided by the models made possible the planning of a flight synchronised with the peak of a particularly strong event and indicated an optimum trajectory for the study of the perturbations induced by these lee waves.
The flight started at night (2:04 local time), heading directly towards the point at 68°S, 68.5 °W, located between the mountains of Liotard (2395 m) and Hope (2865 m) in the Antarctic Peninsula. Here the aircraft turned towards the north-east, flying at 19 km for about 600 km parallel to the Peninsula and perpendicular to the expected lee waves. The aircraft crossed very cold air where the temperature reached -91° C - conditions under which polar stratospheric clouds (PSC) are expected to form. The pilot reported an increase of air turbulence. The lee waves and their effects were simultaneously observed with instruments that analyse the microphysics of aerosols, with in-situ instruments that measure the main atmospheric constituents and tracers, and with spectrometers that retrieve the most significant species for atmospheric chemistry.
At the end of this leginside the area of PSC formation, the aircraft returned to Ushuaia where it landed at 7:40 local time.

23rd September 1999



Second scientific flight



In the first scientific flight more than 80% of the measurements made by the instruments operating on the aircraft were successfully acquired. Preliminary results show clearly a small variation of the atmospheric composition as a function of latitude at the altitude of 14 km and a sharp discontinuity at the altitude of 18 km in correspondence with the crossing of the vortex border. The data analysis and the comparison with the auxiliary measurements acquired by the ground stations is in progress.
Forecasts of atmospheric models have indicated a westerly drift of the vortex border in a location that is still close to South America. Therefore, a second scientific flight has been quickly organised for a second exploration of the vortex with a different flight profile. The flight started at 11.00 local time on the 23rd September. After a fast climb up to an altitude of 17.4 km, the aircraft headed South in the direction 163° and followed a flight profile along an isoentropic surface up to the latitude of about 66°S. Here the aircraft, while continuing in the same direction up to a latitude of about 68° S , performed a dive at the vertical speed of 10 m/sec down to 15 km altitude, then climbed at the speed of 5 m/sec up to 19 km altitude. In this region the aircraft was flying over the Antarctic peninsula very close to some of the ground stations that perform auxiliary measurements. The aircraft turned back towards Ushuaia and performed the return flight with a further climb up to the altitude of 20 km. The landing in Ushuaia occurred at 19.41 local time.
This flight provided a further sampling of the polar vortex at altitudes slightly higher than those of the first flight, as well as daytime observations of photochemistry activation inside the vortex.
The presence in the early part of the campaign of favourable conditions for measurements inside the vortex was on one hand a fortunate coincidence but on the other hand has required a major operational effort with a total of six flights (two transfer, one demonstration, one test and two scientific flights) in eleven days from the 13th to the 23rd of September.

21st September 1999

First scientific flight

The preparation campaign of APE GAIA at middle latitudes, which was performed last March from the airport of Forlì, had its last flight on the 21st of March, in correspondence with the spring equinox of the boreal hemisphere. By chance the first scientific flight of the APE-GAIA campaign in Ushuaia was made on the 21st September, in correspondence with the Spring equinox in the austral hemisphere.
The flight started at 06:15 local time. After a fast climb the aircraft headed directly South (190°) parallel to the thermal gradient at the edge of the polar vortex, going from the latitude of 55° S at Ushuaia to the latitude of 67° S inside the polar vortex. In this leg of the flight the altitude profile was such that the aircraft followed an isoentropic surface which is optimal for the interpretation of the measurements. The latitude of 67°S was reached at 15.5 km altitude. At this point the aircraft turned to the West and made a dive down to 10 km altitude with a vertical speed of 10 m/sec. Then another turn was made pointing straight North and a climb was started with a vertical speed of 5 m/sec up to the altitude of 18 km. At the altitude of 18 km the aircraft headed towards Ushuaia and started the return leg. The landing at Ushuaia occurred at 11.57 local time.
The flight provided information on the chemical composition as a function of altitude at two locations (inside and outside the vortex) as well as detailed observations along the boundaries of the vortex at altitudes between 12 and 14 km.
Further progresses has been made in the construction of the hangar, and the building is now at a sufficient operational level for the activities of the campaign.

19 September 1999

First flight with the scientific payload

The integration on the aircraft of all the scientific instruments has been completed and the aircraft performed a short flight to check the simultaneous operation of all the instruments onboard..
The flight started at 7:00 local time so that the first observations were performed at dawn and the landing was made in daylight. After a rapid climb the aircraft flew for 15 minutes at an altitude of 14 km then climbed further and flew at an altitude of 19 km for 25 minutes. The flight was made in the direction East-West and lasted about two hours from take-off to landing.
First results confirm the correct operation of eleven of the twelve instruments and a first scientific flight is being planned for the 21st of September. Atmospheric models forecast that the polar vortex will be close to the Tierra del Fuego on that date . The objective of the flight is to obtain measurements throughout the thermal gradient which defines the boundary of the vortex, and to travel as deep as possible inside the vortex.

16 September 1999

International Day for the Protection of the Ozone Layer.

Today, 16th September, is the International Day for the Protection of the Ozone Layer. This international day is promoted by the UNEP (United Nations Environmental Programme), which this year selected the town of Ushuaia for the official celebration. Ushuaia being the most south city in the world and the most exposed to the Antarctic ozone hole. As part of this celebration a presentation of the project APE-GAIA has been made.
Mr Ricardo Martin, "Segretario de Desarrollo y Planeamiento", on behalf of the Government of Tierra del Fuego, has welcomed the project. Dr. Bruno Carli, of the Istituto Ricerca sulle Onde Elettromagnetiche "Nello Carrara" of the Italian CNR and Scientific Responsible of the project, described the project, its history and its objectives. Finally Ing. Valery Novikov, Chief Designer of the Myasischev Design Bureau, which built the aircraft Geophysica, brought the greetings of the Russian engineers and technicians.
During the presentation, theGeophysica aircraft was parked next to the conference meeting room. At the end of the presentation made a short demonstration flight with elegant displays over the airport and the town of Ushuaia.
Numerous civil, military and religious authorities as well as representatives of United Nations organisations (UNEP, UNDP), attended the presentation..

14 September 1999

Landing at Ushuaia

On 14 September, at 1.16 p.m. local time, the Russian M-55 Geophysica aircraft landed at the airport of Ushuaia. This flight completed the transfer operations which took the aircraft from Moscow to the extreme tip of South America in eleven days with six flights.
All the flights took place according to plan, with no delay thanks to both the favourable weather conditions and the logistic help provided by the visited countries. The long time required for the transfer operations is due to the peculiar operational features of this aircraft. Only one pilot is on-board of the aircraft and wears a space suit. Safety considerations prevent flights longer than six hours and different pilots must operate the aircraft in case of flights close together. Furthermore, on take-off and landing a team of Russian technicians must service the aircraft so that for each leg more than one team must move with commercial flights in order to service at both airports. The shipment of equipment, the travel of personnel along the transfer trajectory and the management of customs and airport paper work worked out perfectly despite the multi-nationality of the project with its many languages, rules and habits.
During the last week the work for the construction of the new hangar at the airport of Ushuaia progressed significantly, and it was possible to park the aircraft in the hangar, although the construction of the doors is still being completed. Some of the instruments which must operate from the aircraft during the campaign are already onboard the aircraft and others must be mounted in Ushuaia. The lack of a closed area around the aircraft will make difficult for the maintenance of the instruments that are onboard and will cause a delay of a few days in the installation of the other instruments.

September 9, 1999

Crossing of the Atlantic Ocean

Today the Russian M-55 Geophysica aircraft which will be used for the APE-GAIA measurement campaign has landed in Recife (in the North of Brazil).
The landing of a former military Russian aircraft in South America and the crossing of the Atlantic ocean by a stratospheric aircraft are both unique events. The flight is part of the transfer flights that will take the aircraft from its usual home base in Moscow  (Russia) to the operational base of the campaign in Ushuaia (Argentina). It is interesting to note that the starting and the arrival bases are located respectively at 55° N and 55° S. The trip started on the 3rd of September with the first flight from Moscow to Seville (Spain). In Seville, where the aircraft was greeted by the Mayor of the town and by the military authorities of the airport, a first set of instruments was installed on the aircraft. TV news and newspapers highlighted the event. Yesterday, on  8th of  September,  the second flight took the aircraft from Seville to Sal  Island in Cabo Verde. Today was the third flight which landed in Recife.
The aircraft, after a stop in Porto Alegre (in the South of Brasil), is expected to arrive in Ushuaia on the 14th of September. Work is in progress in Ushuaia for setting up the logistics of the campaign operation. The first groups of scientists have already arrived in this little town that claims to be at the end of the world. Many more are expected to arrive in the next few days.
Problems have occurred due to the air-disaster last week at the national airport of Buenos Aires. The subsequent closing of the airport has prevented the shipment of some equipment of the project. Slowly transportation is getting back to normal, but delays are still experienced.
There is a concern for the status of the hangar that will house the 40 meters wide aircraft and protect it from the strong local winds. Construction is still in progress but the engineers aer confident that by the time the aircraft arrives the hangar will be operational. 

26th October 1999

It has been well established that chlorine, put into the atmosphere by the use of chloroflurocarbons (CFCs), causes a large springtime ozone depletion in the southern hemisphere polar `vortex' (the Antarctic Ozone Hole) and a similar, but smaller, depletion in the Arctic. However, many uncertainties remain, especially concerning how this polar depletion contributes to observed ozone decreases at middle latitudes.

International agreements have now phased out the production of these ozone-depleting substances. This is expected to reduce atmospheric chlorine levels over the next 50 years or so, and to lead to a reduction in the size of the springtime Antarctic Ozone Hole on the same timescale. However, climate changes due to the increase in greenhouse gases, which will warm the lower atmosphere and cool the upper atmosphere, may delay this recovery. A more detailed knowledge of the chemistry and dynamics of the Antarctic polar vortex is necessary for accurate predictions of future ozone levels in a colder upper atmosphere.

A new observation platform has been developed with the transformation of the Russian stratospheric aircraft M55-Geophysica (formerly a military reconnaissance plane) into a flying laboratory with twelve complementary scientific instruments that can probe simultaneously the atmosphere. The project started under the auspices of the Italian Programme for Research in Antarctica (PNRA-Programma Nazionale di Ricerche in Antartide), which established in 1995 a collaboration with Myasishchev Design Bureau, the company which built the aircraft for the Russian Defence Ministry in 1988, for the modification of the aircraft and its exploitation in atmospheric research in the Antarctic area. PNRA is a programme of the Italian Ministry of University and Scientific and Technological Research. Since then the project has gained the interest and the contribution of other national and European Research Agencies such as ASI (Agenzia Spaziale Italiana), CNR (Consiglio Nazionale delle Ricerche), BMBF (Bundesministerium für Bildung, Wissenschaft, Forschung and Technologie), NERC (U.K. Natural Environment Research Council), Royal Society (U.K.), Observatory of Neuchatel (Switzerland), ESF (European Science Foundation), EU (European Union), which concurred in the development of new dedicated instrumentation and in the execution of intermediate campaigns.

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The Antarctic campaign of this new observation platform, named APE-GAIA (Airborne Polar Experiment - Geophysica Aircraft In Antarctica), was performed from the 15th of September to the 15th of October from the airport of Ushuaia in Argentina and will be completed in Seville (Spain) on the 28th of October. APE-GAIA was performed with the scientific direction of Dott. Bruno Carli of CNR and the technical direction of Ing. Giuseppe De Rossi of ENEA (Ente Nazionale nuove tecnologie per l’Energia e l’Ambiente).

The M55- Geophysica is an all-weather single seated stratospheric aircraft capable of operating even in severe environmental conditions (e.g. temperatures down to – 90 °C, cross winds at take-off and landing that are strong for such high-altitude aircraft) which reaches for about five hours up to an altitude of 21 km. These characteristics together with the possibility of housing a scientific payload of up to 1,500 kg in a volume of more than 10 m3 with 3 kWatt of power make the M-55 Geophysica an ideal platform for research in the upper troposphere and lower stratosphere.

Significant engineering work was necessary for the modification of the aircraft so that power, navigation data, mechanical interfaces, windows and inlets could be provided to all the instruments. Furthermore, each instrument was built and qualified to operate in the unpressurised aircraft at low temperatures with possible severe accelerations and vibrations.

The payload includes spectrometers for the analysis of the atmospheric chemical composition with remote sensing measurements from the ultraviolet to the far infrared, lidars for detection of the aerosols and in-situ instruments for the measurement of both the main atmospheric constituents for monitoring of depletion processes and tracer species for the identification of dynamical processes.

From Ushuaia the aircraft made five scientific flights. The flights were planned using daily forecasts of winds and temperatures in the atmosphere from 12 - 20 km for the selection of the flight objectives. With these forecasts the scientists predicted the most interesting phenomena within range of the Geophysica and planned the optimum time and path of the flight. In this way the aircraft flew trough the boundaries of the ozone hole several times during the month of operations, was able to sample filaments of air being stripped from the polar vortex and small regions of cold temperature caused at high altitudes by strong winds blowing at low altitudes over mountains on the Antarctic peninsula.

The polar vortex is the area of spiral movement of high altitude air masses that occurs over the polar region in the cold season as a consequence of the collapse of cold air and the gathering of new air from middle latitudes (where the Earth’s rotation has a stronger effect).

Several ground stations both in Latin America and in Antarctica have participated at the campaign with co-ordinated measurements performed during each scientific flight. These localised remote observations provide together with the coarse global picture of satellite measurements the background information for the correct collocation of the detailed measurements obtained with the aircraft instrumentation.

About 70 scientists, engineers and technicians have been operating in Ushuaia during the campaign, and almost as many at other locations have been involved in related activities of modelling, data analysis, auxiliary measurements and logistic organisation from a total of eleven countries (Italy, Russia, Germany, United Kingdom, Switzerland, Finland, Spain, Argentina, United States, Brazil, Chile).

The flights for the transfer of the aircraft from Moscow at 55° N to Ushuaia at 55° S and back have been used in the return leg to perform further scientific measurements that will provide a continuous detailed monitoring over a very wide latitude range.

The operational objectives of the Antarctic campaign have been fully met with accurate forecast of the phenomena, timely operation of both the aircraft and the instruments, and high quality of the acquired data.

Some first scientific results were available in real time during the campaign. These show the occurrence of large ice particles at 20 km altitude in the cold regions generated by orographic waves above the Antarctic mountains. Results from flights performed at the lower altitude of 14 km indicate a greater mixing of the polar vortex at this altitude compared to 18 km, which will allow greater transport of polar air to mid-latitudes.

The majority of the data will require, however, a more elaborate analysis process, and does not allow yet conclusive statements. A complete assessment of the acquired information will involve comparisons between the instruments and testing of consistency of the models with the observations. It is expected that the campaign will provide useful information on the processes controlling ozone in the atmosphere and will improve our estimate of Antarctic ozone recovery time after the phasing out of CFCs .