Mesoscale Transport of Atmospheric Trace Gases Across the Alps : The TRANSALP 1991 Campaign
The third TRANSALP campaign that took place on September-October 1991, consisted of 2 experiments: the first investigated the air flow across the Alps in North-South direction, over an extended area ranging from the Lake of Uzern to Lake Maggiore for a distance of about 100 km; the second was carried under purely thermic wind conditions over a complex terrain around the northern slops of the Lake of Luzern. For the first release surface meterological measurements for a total of approximately 50 sites are presented. Furthermore, data from 3 Acoustic Doppler Sounders (Sodars), tethered balloons and pilot balloons providing information on the vertical structure of the atmosphere, as well as vertical profiles of dry-wet bulb temperatures, potential temperature, relative humidity were also obtained. Tracer measurements were performed in about 60 stations at ground level for the first release and were continued for a period up to 52 hours. Concentration values were also measured from aircraft sampling, by which a description was obtained of the vertical tracer distribution during the day following the release. Considering the results of the 1991 TRANSALP experiment as presented in this report, there is clear evidence that the tracer was channelled in the North- South direction throughout Reuss valley, then lifted over the Gotthard Pass and channelled again in Leventina valley by the nocturnal drainage flow to the Lake Maggiore area. The information presented in this report is intended to stimulate modellers to reproduce this transport path, thereby achieving more general knowledge of the transport mechanisms across the Alps.
Bibliographic Reference: EUR 16046 EN (1994) 67pp., FS
Availability: Available from the Public Relations and Publications Unit, JRC Ispra, I-21020 Ispra (IT)
Record Number: 199411660 / Last updated on: 1995-03-21
Original language: en
Available languages: en