ENVINET Activities Catalog

ENVINET Activities Catalog





Displaying: 1 - 6 of 6


2. SCIAMACHY validation with FTIR


3. Water vapour balloon soundings


4. Stratospheric ozone loss determination (Match)

By launching several hundred ozonesondes and by ozone lidar measurements at many Arctic and sub-Arctic stations, one of them Ny-Ålesund, the stratospheric chemical ozone loss will be determined. The launches of all stations will be coordinated by analysis of trajectory calculations based on analysis and forecast wind fields. The aim is to get as many ozone sounding pairs as possible, each of them linked by trajectories in space and time. A statistical description of the ozone differencies given by the first and the second measurement of individual sonde pairs will yield the chemical ozone loss with spatial and time resolution. Four similar campaigns took place in the Arctic and in the mid-latitudes covering the time period of Januar to March in each of the last four winters. In the first three winters high ozone depletion rates (20 - 50 ppbv per day) were determined in some height levels within the polar vortex. In the height level of the ozone maximum an integrated ozone loss (during the winter) in the order of 60 % have been found. These are record ozone losses for the Arctic polar region. In the last winter the ozone depletion rates had been much lower due to moderate temperatures in the stratosphere.

Atmospheric processes Ozone MATCH Climate variability Stratosphere Climate Spatial trends Climate change Ozonesonde Arctic Atmosphere Temporal trends


6. Stratospheric observations with LIDAR technique (NDSC)

The stratospheric multi wavelength LIDAR instrument, which is part of the NDSC contribution of the Koldewey-Station, consists of two lasers, a XeCl-Excimer laser for UV-wavelengths and a Nd:YAG-laser for near IR- and visible wavelengths, two telescopes (of 60 cm and 150 cm diameter) and a detection system with eight channels. Ozone profiles are obtained by the DIAL method using the wavelengths at 308 and 353 nm. Aerosol data is recorded at three wavelengths (353 nm, 532 nm, 1064 nm) with depolarization measurements at 532 nm. In addition the vibrational N2-Raman scattered light at 608 nm is recorded. As lidar measurements require clear skies and a low background light level, the observations are concentrated on the winter months from November through March. The most prominent feature is the regular observation of Polar Stratospheric Clouds (PSCs). PSCs are known to be a necessary prerequisite for the strong polar ozone loss, which is observed in the Arctic (and above Spitsbergen). The PSC data set accumulated during the last years allows the characterization of the various types of PSCs and how they form and develop. The 353 and 532 nm channels are also used for temperature retrievals in the altitude range above the aerosol layer up to 50 km.

Aerosols Atmospheric processes Ozone Polar Stratospheric Clouds UV radiation Geophysics Climate variability stratosphere Climate Climate change Aerosol Arctic PSCs Atmosphere LIDAR UV